Commit | Line | Data |
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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" | |
3993f6b1 | 26 | #include "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" |
5808517f YQ |
61 | #include "agent.h" |
62 | #include "tracepoint.h" | |
87b0bb13 | 63 | #include "buffer.h" |
6ecd4729 | 64 | #include "target-descriptions.h" |
614c279d | 65 | #include "filestuff.h" |
77e371c0 | 66 | #include "objfiles.h" |
7a6a1731 GB |
67 | #include "nat/linux-namespaces.h" |
68 | #include "fileio.h" | |
1db93f14 | 69 | #include "common/scope-exit.h" |
efcbbd14 UW |
70 | |
71 | #ifndef SPUFS_MAGIC | |
72 | #define SPUFS_MAGIC 0x23c9b64e | |
73 | #endif | |
dba24537 | 74 | |
1777feb0 | 75 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
76 | |
77 | Waiting for events in sync mode | |
78 | =============================== | |
79 | ||
4a6ed09b PA |
80 | When waiting for an event in a specific thread, we just use waitpid, |
81 | passing the specific pid, and not passing WNOHANG. | |
82 | ||
83 | When waiting for an event in all threads, waitpid is not quite good: | |
84 | ||
85 | - If the thread group leader exits while other threads in the thread | |
86 | group still exist, waitpid(TGID, ...) hangs. That waitpid won't | |
87 | return an exit status until the other threads in the group are | |
88 | reaped. | |
89 | ||
90 | - When a non-leader thread execs, that thread just vanishes without | |
91 | reporting an exit (so we'd hang if we waited for it explicitly in | |
92 | that case). The exec event is instead reported to the TGID pid. | |
93 | ||
94 | The solution is to always use -1 and WNOHANG, together with | |
95 | sigsuspend. | |
96 | ||
97 | First, we use non-blocking waitpid to check for events. If nothing is | |
98 | found, we use sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, | |
99 | it means something happened to a child process. As soon as we know | |
100 | there's an event, we get back to calling nonblocking waitpid. | |
101 | ||
102 | Note that SIGCHLD should be blocked between waitpid and sigsuspend | |
103 | calls, so that we don't miss a signal. If SIGCHLD arrives in between, | |
104 | when it's blocked, the signal becomes pending and sigsuspend | |
105 | immediately notices it and returns. | |
106 | ||
107 | Waiting for events in async mode (TARGET_WNOHANG) | |
108 | ================================================= | |
8a77dff3 | 109 | |
7feb7d06 PA |
110 | In async mode, GDB should always be ready to handle both user input |
111 | and target events, so neither blocking waitpid nor sigsuspend are | |
112 | viable options. Instead, we should asynchronously notify the GDB main | |
113 | event loop whenever there's an unprocessed event from the target. We | |
114 | detect asynchronous target events by handling SIGCHLD signals. To | |
115 | notify the event loop about target events, the self-pipe trick is used | |
116 | --- a pipe is registered as waitable event source in the event loop, | |
117 | the event loop select/poll's on the read end of this pipe (as well on | |
118 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
119 | byte to this pipe. This is more portable than relying on | |
120 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
121 | emulates them with select/poll+sigprocmask, and that is racy | |
122 | (a.k.a. plain broken). | |
123 | ||
124 | Obviously, if we fail to notify the event loop if there's a target | |
125 | event, it's bad. OTOH, if we notify the event loop when there's no | |
126 | event from the target, linux_nat_wait will detect that there's no real | |
127 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
128 | This is mostly harmless, but it will waste time and is better avoided. | |
129 | ||
130 | The main design point is that every time GDB is outside linux-nat.c, | |
131 | we have a SIGCHLD handler installed that is called when something | |
132 | happens to the target and notifies the GDB event loop. Whenever GDB | |
133 | core decides to handle the event, and calls into linux-nat.c, we | |
134 | process things as in sync mode, except that the we never block in | |
135 | sigsuspend. | |
136 | ||
137 | While processing an event, we may end up momentarily blocked in | |
138 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
139 | return quickly. E.g., in all-stop mode, before reporting to the core | |
140 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
141 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
142 | Note that this is different from blocking indefinitely waiting for the | |
143 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
144 | |
145 | Use of signals | |
146 | ============== | |
147 | ||
148 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
149 | signal is not entirely significant; we just need for a signal to be delivered, | |
150 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
151 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
152 | be queued once; we do not keep track of other sources of SIGSTOP. | |
153 | ||
154 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
155 | use them, because they have special behavior when the signal is generated - | |
156 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
157 | kills the entire thread group. | |
158 | ||
159 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
160 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
161 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
162 | ||
163 | We could use a real-time signal instead. This would solve those problems; we | |
164 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
165 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
166 | generates it, and there are races with trying to find a signal that is not | |
4a6ed09b PA |
167 | blocked. |
168 | ||
169 | Exec events | |
170 | =========== | |
171 | ||
172 | The case of a thread group (process) with 3 or more threads, and a | |
173 | thread other than the leader execs is worth detailing: | |
174 | ||
175 | On an exec, the Linux kernel destroys all threads except the execing | |
176 | one in the thread group, and resets the execing thread's tid to the | |
177 | tgid. No exit notification is sent for the execing thread -- from the | |
178 | ptracer's perspective, it appears as though the execing thread just | |
179 | vanishes. Until we reap all other threads except the leader and the | |
180 | execing thread, the leader will be zombie, and the execing thread will | |
181 | be in `D (disc sleep)' state. As soon as all other threads are | |
182 | reaped, the execing thread changes its tid to the tgid, and the | |
183 | previous (zombie) leader vanishes, giving place to the "new" | |
184 | leader. */ | |
a0ef4274 | 185 | |
dba24537 AC |
186 | #ifndef O_LARGEFILE |
187 | #define O_LARGEFILE 0 | |
188 | #endif | |
0274a8ce | 189 | |
f6ac5f3d PA |
190 | struct linux_nat_target *linux_target; |
191 | ||
433bbbf8 | 192 | /* Does the current host support PTRACE_GETREGSET? */ |
0bdb2f78 | 193 | enum tribool have_ptrace_getregset = TRIBOOL_UNKNOWN; |
433bbbf8 | 194 | |
ccce17b0 | 195 | static unsigned int debug_linux_nat; |
920d2a44 AC |
196 | static void |
197 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
198 | struct cmd_list_element *c, const char *value) | |
199 | { | |
200 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
201 | value); | |
202 | } | |
d6b0e80f | 203 | |
ae087d01 DJ |
204 | struct simple_pid_list |
205 | { | |
206 | int pid; | |
3d799a95 | 207 | int status; |
ae087d01 DJ |
208 | struct simple_pid_list *next; |
209 | }; | |
210 | struct simple_pid_list *stopped_pids; | |
211 | ||
aa01bd36 PA |
212 | /* Whether target_thread_events is in effect. */ |
213 | static int report_thread_events; | |
214 | ||
3dd5b83d PA |
215 | /* Async mode support. */ |
216 | ||
b84876c2 PA |
217 | /* The read/write ends of the pipe registered as waitable file in the |
218 | event loop. */ | |
219 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
220 | ||
198297aa PA |
221 | /* True if we're currently in async mode. */ |
222 | #define linux_is_async_p() (linux_nat_event_pipe[0] != -1) | |
223 | ||
7feb7d06 | 224 | /* Flush the event pipe. */ |
b84876c2 | 225 | |
7feb7d06 PA |
226 | static void |
227 | async_file_flush (void) | |
b84876c2 | 228 | { |
7feb7d06 PA |
229 | int ret; |
230 | char buf; | |
b84876c2 | 231 | |
7feb7d06 | 232 | do |
b84876c2 | 233 | { |
7feb7d06 | 234 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 235 | } |
7feb7d06 | 236 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
237 | } |
238 | ||
7feb7d06 PA |
239 | /* Put something (anything, doesn't matter what, or how much) in event |
240 | pipe, so that the select/poll in the event-loop realizes we have | |
241 | something to process. */ | |
252fbfc8 | 242 | |
b84876c2 | 243 | static void |
7feb7d06 | 244 | async_file_mark (void) |
b84876c2 | 245 | { |
7feb7d06 | 246 | int ret; |
b84876c2 | 247 | |
7feb7d06 PA |
248 | /* It doesn't really matter what the pipe contains, as long we end |
249 | up with something in it. Might as well flush the previous | |
250 | left-overs. */ | |
251 | async_file_flush (); | |
b84876c2 | 252 | |
7feb7d06 | 253 | do |
b84876c2 | 254 | { |
7feb7d06 | 255 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 256 | } |
7feb7d06 | 257 | while (ret == -1 && errno == EINTR); |
b84876c2 | 258 | |
7feb7d06 PA |
259 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
260 | be awakened anyway. */ | |
b84876c2 PA |
261 | } |
262 | ||
7feb7d06 PA |
263 | static int kill_lwp (int lwpid, int signo); |
264 | ||
265 | static int stop_callback (struct lwp_info *lp, void *data); | |
2db9a427 | 266 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
7feb7d06 PA |
267 | |
268 | static void block_child_signals (sigset_t *prev_mask); | |
269 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
270 | |
271 | struct lwp_info; | |
272 | static struct lwp_info *add_lwp (ptid_t ptid); | |
273 | static void purge_lwp_list (int pid); | |
4403d8e9 | 274 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
275 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
276 | ||
8a99810d PA |
277 | static int lwp_status_pending_p (struct lwp_info *lp); |
278 | ||
e7ad2f14 PA |
279 | static void save_stop_reason (struct lwp_info *lp); |
280 | ||
cff068da GB |
281 | \f |
282 | /* LWP accessors. */ | |
283 | ||
284 | /* See nat/linux-nat.h. */ | |
285 | ||
286 | ptid_t | |
287 | ptid_of_lwp (struct lwp_info *lwp) | |
288 | { | |
289 | return lwp->ptid; | |
290 | } | |
291 | ||
292 | /* See nat/linux-nat.h. */ | |
293 | ||
4b134ca1 GB |
294 | void |
295 | lwp_set_arch_private_info (struct lwp_info *lwp, | |
296 | struct arch_lwp_info *info) | |
297 | { | |
298 | lwp->arch_private = info; | |
299 | } | |
300 | ||
301 | /* See nat/linux-nat.h. */ | |
302 | ||
303 | struct arch_lwp_info * | |
304 | lwp_arch_private_info (struct lwp_info *lwp) | |
305 | { | |
306 | return lwp->arch_private; | |
307 | } | |
308 | ||
309 | /* See nat/linux-nat.h. */ | |
310 | ||
cff068da GB |
311 | int |
312 | lwp_is_stopped (struct lwp_info *lwp) | |
313 | { | |
314 | return lwp->stopped; | |
315 | } | |
316 | ||
317 | /* See nat/linux-nat.h. */ | |
318 | ||
319 | enum target_stop_reason | |
320 | lwp_stop_reason (struct lwp_info *lwp) | |
321 | { | |
322 | return lwp->stop_reason; | |
323 | } | |
324 | ||
0e00e962 AA |
325 | /* See nat/linux-nat.h. */ |
326 | ||
327 | int | |
328 | lwp_is_stepping (struct lwp_info *lwp) | |
329 | { | |
330 | return lwp->step; | |
331 | } | |
332 | ||
ae087d01 DJ |
333 | \f |
334 | /* Trivial list manipulation functions to keep track of a list of | |
335 | new stopped processes. */ | |
336 | static void | |
3d799a95 | 337 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 | 338 | { |
8d749320 | 339 | struct simple_pid_list *new_pid = XNEW (struct simple_pid_list); |
e0881a8e | 340 | |
ae087d01 | 341 | new_pid->pid = pid; |
3d799a95 | 342 | new_pid->status = status; |
ae087d01 DJ |
343 | new_pid->next = *listp; |
344 | *listp = new_pid; | |
345 | } | |
346 | ||
347 | static int | |
46a96992 | 348 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
349 | { |
350 | struct simple_pid_list **p; | |
351 | ||
352 | for (p = listp; *p != NULL; p = &(*p)->next) | |
353 | if ((*p)->pid == pid) | |
354 | { | |
355 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 356 | |
46a96992 | 357 | *statusp = (*p)->status; |
ae087d01 DJ |
358 | xfree (*p); |
359 | *p = next; | |
360 | return 1; | |
361 | } | |
362 | return 0; | |
363 | } | |
364 | ||
de0d863e DB |
365 | /* Return the ptrace options that we want to try to enable. */ |
366 | ||
367 | static int | |
368 | linux_nat_ptrace_options (int attached) | |
369 | { | |
370 | int options = 0; | |
371 | ||
372 | if (!attached) | |
373 | options |= PTRACE_O_EXITKILL; | |
374 | ||
375 | options |= (PTRACE_O_TRACESYSGOOD | |
376 | | PTRACE_O_TRACEVFORKDONE | |
377 | | PTRACE_O_TRACEVFORK | |
378 | | PTRACE_O_TRACEFORK | |
379 | | PTRACE_O_TRACEEXEC); | |
380 | ||
381 | return options; | |
382 | } | |
383 | ||
1b919490 VB |
384 | /* Initialize ptrace and procfs warnings and check for supported |
385 | ptrace features given PID. | |
beed38b8 JB |
386 | |
387 | ATTACHED should be nonzero iff we attached to the inferior. */ | |
3993f6b1 DJ |
388 | |
389 | static void | |
1b919490 | 390 | linux_init_ptrace_procfs (pid_t pid, int attached) |
3993f6b1 | 391 | { |
de0d863e DB |
392 | int options = linux_nat_ptrace_options (attached); |
393 | ||
394 | linux_enable_event_reporting (pid, options); | |
96d7229d | 395 | linux_ptrace_init_warnings (); |
1b919490 | 396 | linux_proc_init_warnings (); |
4de4c07c DJ |
397 | } |
398 | ||
f6ac5f3d PA |
399 | linux_nat_target::~linux_nat_target () |
400 | {} | |
401 | ||
402 | void | |
403 | linux_nat_target::post_attach (int pid) | |
4de4c07c | 404 | { |
1b919490 | 405 | linux_init_ptrace_procfs (pid, 1); |
4de4c07c DJ |
406 | } |
407 | ||
f6ac5f3d PA |
408 | void |
409 | linux_nat_target::post_startup_inferior (ptid_t ptid) | |
4de4c07c | 410 | { |
1b919490 | 411 | linux_init_ptrace_procfs (ptid.pid (), 0); |
4de4c07c DJ |
412 | } |
413 | ||
4403d8e9 JK |
414 | /* Return the number of known LWPs in the tgid given by PID. */ |
415 | ||
416 | static int | |
417 | num_lwps (int pid) | |
418 | { | |
419 | int count = 0; | |
420 | struct lwp_info *lp; | |
421 | ||
422 | for (lp = lwp_list; lp; lp = lp->next) | |
e99b03dc | 423 | if (lp->ptid.pid () == pid) |
4403d8e9 JK |
424 | count++; |
425 | ||
426 | return count; | |
427 | } | |
428 | ||
169bb27b | 429 | /* Deleter for lwp_info unique_ptr specialisation. */ |
4403d8e9 | 430 | |
169bb27b | 431 | struct lwp_deleter |
4403d8e9 | 432 | { |
169bb27b AB |
433 | void operator() (struct lwp_info *lwp) const |
434 | { | |
435 | delete_lwp (lwp->ptid); | |
436 | } | |
437 | }; | |
4403d8e9 | 438 | |
169bb27b AB |
439 | /* A unique_ptr specialisation for lwp_info. */ |
440 | ||
441 | typedef std::unique_ptr<struct lwp_info, lwp_deleter> lwp_info_up; | |
4403d8e9 | 442 | |
d83ad864 DB |
443 | /* Target hook for follow_fork. On entry inferior_ptid must be the |
444 | ptid of the followed inferior. At return, inferior_ptid will be | |
445 | unchanged. */ | |
446 | ||
f6ac5f3d PA |
447 | int |
448 | linux_nat_target::follow_fork (int follow_child, int detach_fork) | |
3993f6b1 | 449 | { |
d83ad864 | 450 | if (!follow_child) |
4de4c07c | 451 | { |
6c95b8df | 452 | struct lwp_info *child_lp = NULL; |
d83ad864 | 453 | int has_vforked; |
79639e11 | 454 | ptid_t parent_ptid, child_ptid; |
d83ad864 DB |
455 | int parent_pid, child_pid; |
456 | ||
457 | has_vforked = (inferior_thread ()->pending_follow.kind | |
458 | == TARGET_WAITKIND_VFORKED); | |
79639e11 PA |
459 | parent_ptid = inferior_ptid; |
460 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; | |
e38504b3 TT |
461 | parent_pid = parent_ptid.lwp (); |
462 | child_pid = child_ptid.lwp (); | |
4de4c07c | 463 | |
1777feb0 | 464 | /* We're already attached to the parent, by default. */ |
2989a365 | 465 | child_lp = add_lwp (child_ptid); |
d83ad864 DB |
466 | child_lp->stopped = 1; |
467 | child_lp->last_resume_kind = resume_stop; | |
4de4c07c | 468 | |
ac264b3b MS |
469 | /* Detach new forked process? */ |
470 | if (detach_fork) | |
f75c00e4 | 471 | { |
95347337 AB |
472 | int child_stop_signal = 0; |
473 | bool detach_child = true; | |
4403d8e9 | 474 | |
169bb27b AB |
475 | /* Move CHILD_LP into a unique_ptr and clear the source pointer |
476 | to prevent us doing anything stupid with it. */ | |
477 | lwp_info_up child_lp_ptr (child_lp); | |
478 | child_lp = nullptr; | |
479 | ||
480 | linux_target->low_prepare_to_resume (child_lp_ptr.get ()); | |
c077881a HZ |
481 | |
482 | /* When debugging an inferior in an architecture that supports | |
483 | hardware single stepping on a kernel without commit | |
484 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
485 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
486 | set if the parent process had them set. | |
487 | To work around this, single step the child process | |
488 | once before detaching to clear the flags. */ | |
489 | ||
2fd9d7ca PA |
490 | /* Note that we consult the parent's architecture instead of |
491 | the child's because there's no inferior for the child at | |
492 | this point. */ | |
c077881a | 493 | if (!gdbarch_software_single_step_p (target_thread_architecture |
2fd9d7ca | 494 | (parent_ptid))) |
c077881a | 495 | { |
95347337 AB |
496 | int status; |
497 | ||
c077881a HZ |
498 | linux_disable_event_reporting (child_pid); |
499 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
500 | perror_with_name (_("Couldn't do single step")); | |
501 | if (my_waitpid (child_pid, &status, 0) < 0) | |
502 | perror_with_name (_("Couldn't wait vfork process")); | |
95347337 AB |
503 | else |
504 | { | |
505 | detach_child = WIFSTOPPED (status); | |
506 | child_stop_signal = WSTOPSIG (status); | |
507 | } | |
c077881a HZ |
508 | } |
509 | ||
95347337 | 510 | if (detach_child) |
9caaaa83 | 511 | { |
95347337 | 512 | int signo = child_stop_signal; |
9caaaa83 | 513 | |
9caaaa83 PA |
514 | if (signo != 0 |
515 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
516 | signo = 0; | |
517 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
518 | } | |
ac264b3b MS |
519 | } |
520 | else | |
521 | { | |
2989a365 TT |
522 | scoped_restore save_inferior_ptid |
523 | = make_scoped_restore (&inferior_ptid); | |
524 | inferior_ptid = child_ptid; | |
525 | ||
6c95b8df | 526 | /* Let the thread_db layer learn about this new process. */ |
2277426b | 527 | check_for_thread_db (); |
ac264b3b | 528 | } |
9016a515 DJ |
529 | |
530 | if (has_vforked) | |
531 | { | |
3ced3da4 | 532 | struct lwp_info *parent_lp; |
6c95b8df | 533 | |
79639e11 | 534 | parent_lp = find_lwp_pid (parent_ptid); |
96d7229d | 535 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 536 | |
96d7229d | 537 | if (linux_supports_tracevforkdone ()) |
9016a515 | 538 | { |
6c95b8df PA |
539 | if (debug_linux_nat) |
540 | fprintf_unfiltered (gdb_stdlog, | |
541 | "LCFF: waiting for VFORK_DONE on %d\n", | |
542 | parent_pid); | |
3ced3da4 | 543 | parent_lp->stopped = 1; |
9016a515 | 544 | |
6c95b8df PA |
545 | /* We'll handle the VFORK_DONE event like any other |
546 | event, in target_wait. */ | |
9016a515 DJ |
547 | } |
548 | else | |
549 | { | |
550 | /* We can't insert breakpoints until the child has | |
551 | finished with the shared memory region. We need to | |
552 | wait until that happens. Ideal would be to just | |
553 | call: | |
554 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
555 | - waitpid (parent_pid, &status, __WALL); | |
556 | However, most architectures can't handle a syscall | |
557 | being traced on the way out if it wasn't traced on | |
558 | the way in. | |
559 | ||
560 | We might also think to loop, continuing the child | |
561 | until it exits or gets a SIGTRAP. One problem is | |
562 | that the child might call ptrace with PTRACE_TRACEME. | |
563 | ||
564 | There's no simple and reliable way to figure out when | |
565 | the vforked child will be done with its copy of the | |
566 | shared memory. We could step it out of the syscall, | |
567 | two instructions, let it go, and then single-step the | |
568 | parent once. When we have hardware single-step, this | |
569 | would work; with software single-step it could still | |
570 | be made to work but we'd have to be able to insert | |
571 | single-step breakpoints in the child, and we'd have | |
572 | to insert -just- the single-step breakpoint in the | |
573 | parent. Very awkward. | |
574 | ||
575 | In the end, the best we can do is to make sure it | |
576 | runs for a little while. Hopefully it will be out of | |
577 | range of any breakpoints we reinsert. Usually this | |
578 | is only the single-step breakpoint at vfork's return | |
579 | point. */ | |
580 | ||
6c95b8df PA |
581 | if (debug_linux_nat) |
582 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
583 | "LCFF: no VFORK_DONE " |
584 | "support, sleeping a bit\n"); | |
6c95b8df | 585 | |
9016a515 | 586 | usleep (10000); |
9016a515 | 587 | |
6c95b8df PA |
588 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
589 | and leave it pending. The next linux_nat_resume call | |
590 | will notice a pending event, and bypasses actually | |
591 | resuming the inferior. */ | |
3ced3da4 PA |
592 | parent_lp->status = 0; |
593 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
594 | parent_lp->stopped = 1; | |
6c95b8df PA |
595 | |
596 | /* If we're in async mode, need to tell the event loop | |
597 | there's something here to process. */ | |
d9d41e78 | 598 | if (target_is_async_p ()) |
6c95b8df PA |
599 | async_file_mark (); |
600 | } | |
9016a515 | 601 | } |
4de4c07c | 602 | } |
3993f6b1 | 603 | else |
4de4c07c | 604 | { |
3ced3da4 | 605 | struct lwp_info *child_lp; |
4de4c07c | 606 | |
3ced3da4 PA |
607 | child_lp = add_lwp (inferior_ptid); |
608 | child_lp->stopped = 1; | |
25289eb2 | 609 | child_lp->last_resume_kind = resume_stop; |
6c95b8df | 610 | |
6c95b8df | 611 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 612 | check_for_thread_db (); |
4de4c07c DJ |
613 | } |
614 | ||
615 | return 0; | |
616 | } | |
617 | ||
4de4c07c | 618 | \f |
f6ac5f3d PA |
619 | int |
620 | linux_nat_target::insert_fork_catchpoint (int pid) | |
4de4c07c | 621 | { |
96d7229d | 622 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
623 | } |
624 | ||
f6ac5f3d PA |
625 | int |
626 | linux_nat_target::remove_fork_catchpoint (int pid) | |
eb73ad13 PA |
627 | { |
628 | return 0; | |
629 | } | |
630 | ||
f6ac5f3d PA |
631 | int |
632 | linux_nat_target::insert_vfork_catchpoint (int pid) | |
3993f6b1 | 633 | { |
96d7229d | 634 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
635 | } |
636 | ||
f6ac5f3d PA |
637 | int |
638 | linux_nat_target::remove_vfork_catchpoint (int pid) | |
eb73ad13 PA |
639 | { |
640 | return 0; | |
641 | } | |
642 | ||
f6ac5f3d PA |
643 | int |
644 | linux_nat_target::insert_exec_catchpoint (int pid) | |
3993f6b1 | 645 | { |
96d7229d | 646 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
647 | } |
648 | ||
f6ac5f3d PA |
649 | int |
650 | linux_nat_target::remove_exec_catchpoint (int pid) | |
eb73ad13 PA |
651 | { |
652 | return 0; | |
653 | } | |
654 | ||
f6ac5f3d PA |
655 | int |
656 | linux_nat_target::set_syscall_catchpoint (int pid, bool needed, int any_count, | |
657 | gdb::array_view<const int> syscall_counts) | |
a96d9b2e | 658 | { |
96d7229d | 659 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
660 | return 1; |
661 | ||
a96d9b2e SDJ |
662 | /* On GNU/Linux, we ignore the arguments. It means that we only |
663 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 664 | |
649a140c | 665 | Also, we do not use the `syscall_counts' information because we do not |
a96d9b2e SDJ |
666 | filter system calls here. We let GDB do the logic for us. */ |
667 | return 0; | |
668 | } | |
669 | ||
774113b0 PA |
670 | /* List of known LWPs, keyed by LWP PID. This speeds up the common |
671 | case of mapping a PID returned from the kernel to our corresponding | |
672 | lwp_info data structure. */ | |
673 | static htab_t lwp_lwpid_htab; | |
674 | ||
675 | /* Calculate a hash from a lwp_info's LWP PID. */ | |
676 | ||
677 | static hashval_t | |
678 | lwp_info_hash (const void *ap) | |
679 | { | |
680 | const struct lwp_info *lp = (struct lwp_info *) ap; | |
e38504b3 | 681 | pid_t pid = lp->ptid.lwp (); |
774113b0 PA |
682 | |
683 | return iterative_hash_object (pid, 0); | |
684 | } | |
685 | ||
686 | /* Equality function for the lwp_info hash table. Compares the LWP's | |
687 | PID. */ | |
688 | ||
689 | static int | |
690 | lwp_lwpid_htab_eq (const void *a, const void *b) | |
691 | { | |
692 | const struct lwp_info *entry = (const struct lwp_info *) a; | |
693 | const struct lwp_info *element = (const struct lwp_info *) b; | |
694 | ||
e38504b3 | 695 | return entry->ptid.lwp () == element->ptid.lwp (); |
774113b0 PA |
696 | } |
697 | ||
698 | /* Create the lwp_lwpid_htab hash table. */ | |
699 | ||
700 | static void | |
701 | lwp_lwpid_htab_create (void) | |
702 | { | |
703 | lwp_lwpid_htab = htab_create (100, lwp_info_hash, lwp_lwpid_htab_eq, NULL); | |
704 | } | |
705 | ||
706 | /* Add LP to the hash table. */ | |
707 | ||
708 | static void | |
709 | lwp_lwpid_htab_add_lwp (struct lwp_info *lp) | |
710 | { | |
711 | void **slot; | |
712 | ||
713 | slot = htab_find_slot (lwp_lwpid_htab, lp, INSERT); | |
714 | gdb_assert (slot != NULL && *slot == NULL); | |
715 | *slot = lp; | |
716 | } | |
717 | ||
718 | /* Head of doubly-linked list of known LWPs. Sorted by reverse | |
719 | creation order. This order is assumed in some cases. E.g., | |
720 | reaping status after killing alls lwps of a process: the leader LWP | |
721 | must be reaped last. */ | |
9f0bdab8 | 722 | struct lwp_info *lwp_list; |
774113b0 PA |
723 | |
724 | /* Add LP to sorted-by-reverse-creation-order doubly-linked list. */ | |
725 | ||
726 | static void | |
727 | lwp_list_add (struct lwp_info *lp) | |
728 | { | |
729 | lp->next = lwp_list; | |
730 | if (lwp_list != NULL) | |
731 | lwp_list->prev = lp; | |
732 | lwp_list = lp; | |
733 | } | |
734 | ||
735 | /* Remove LP from sorted-by-reverse-creation-order doubly-linked | |
736 | list. */ | |
737 | ||
738 | static void | |
739 | lwp_list_remove (struct lwp_info *lp) | |
740 | { | |
741 | /* Remove from sorted-by-creation-order list. */ | |
742 | if (lp->next != NULL) | |
743 | lp->next->prev = lp->prev; | |
744 | if (lp->prev != NULL) | |
745 | lp->prev->next = lp->next; | |
746 | if (lp == lwp_list) | |
747 | lwp_list = lp->next; | |
748 | } | |
749 | ||
d6b0e80f AC |
750 | \f |
751 | ||
d6b0e80f AC |
752 | /* Original signal mask. */ |
753 | static sigset_t normal_mask; | |
754 | ||
755 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
756 | _initialize_linux_nat. */ | |
757 | static sigset_t suspend_mask; | |
758 | ||
7feb7d06 PA |
759 | /* Signals to block to make that sigsuspend work. */ |
760 | static sigset_t blocked_mask; | |
761 | ||
762 | /* SIGCHLD action. */ | |
763 | struct sigaction sigchld_action; | |
b84876c2 | 764 | |
7feb7d06 PA |
765 | /* Block child signals (SIGCHLD and linux threads signals), and store |
766 | the previous mask in PREV_MASK. */ | |
84e46146 | 767 | |
7feb7d06 PA |
768 | static void |
769 | block_child_signals (sigset_t *prev_mask) | |
770 | { | |
771 | /* Make sure SIGCHLD is blocked. */ | |
772 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
773 | sigaddset (&blocked_mask, SIGCHLD); | |
774 | ||
775 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
776 | } | |
777 | ||
778 | /* Restore child signals mask, previously returned by | |
779 | block_child_signals. */ | |
780 | ||
781 | static void | |
782 | restore_child_signals_mask (sigset_t *prev_mask) | |
783 | { | |
784 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
785 | } | |
2455069d UW |
786 | |
787 | /* Mask of signals to pass directly to the inferior. */ | |
788 | static sigset_t pass_mask; | |
789 | ||
790 | /* Update signals to pass to the inferior. */ | |
f6ac5f3d | 791 | void |
491adeca | 792 | linux_nat_target::pass_signals (int numsigs, const unsigned char *pass_signals) |
2455069d UW |
793 | { |
794 | int signo; | |
795 | ||
796 | sigemptyset (&pass_mask); | |
797 | ||
798 | for (signo = 1; signo < NSIG; signo++) | |
799 | { | |
2ea28649 | 800 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
801 | if (target_signo < numsigs && pass_signals[target_signo]) |
802 | sigaddset (&pass_mask, signo); | |
803 | } | |
804 | } | |
805 | ||
d6b0e80f AC |
806 | \f |
807 | ||
808 | /* Prototypes for local functions. */ | |
809 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
20ba1ce6 | 810 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
ced2dffb | 811 | static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp); |
710151dd | 812 | |
d6b0e80f | 813 | \f |
d6b0e80f | 814 | |
7b50312a PA |
815 | /* Destroy and free LP. */ |
816 | ||
817 | static void | |
818 | lwp_free (struct lwp_info *lp) | |
819 | { | |
466eecee | 820 | /* Let the arch specific bits release arch_lwp_info. */ |
135340af | 821 | linux_target->low_delete_thread (lp->arch_private); |
466eecee | 822 | |
7b50312a PA |
823 | xfree (lp); |
824 | } | |
825 | ||
774113b0 | 826 | /* Traversal function for purge_lwp_list. */ |
d90e17a7 | 827 | |
774113b0 PA |
828 | static int |
829 | lwp_lwpid_htab_remove_pid (void **slot, void *info) | |
d90e17a7 | 830 | { |
774113b0 PA |
831 | struct lwp_info *lp = (struct lwp_info *) *slot; |
832 | int pid = *(int *) info; | |
d90e17a7 | 833 | |
e99b03dc | 834 | if (lp->ptid.pid () == pid) |
d90e17a7 | 835 | { |
774113b0 PA |
836 | htab_clear_slot (lwp_lwpid_htab, slot); |
837 | lwp_list_remove (lp); | |
838 | lwp_free (lp); | |
839 | } | |
d90e17a7 | 840 | |
774113b0 PA |
841 | return 1; |
842 | } | |
d90e17a7 | 843 | |
774113b0 PA |
844 | /* Remove all LWPs belong to PID from the lwp list. */ |
845 | ||
846 | static void | |
847 | purge_lwp_list (int pid) | |
848 | { | |
849 | htab_traverse_noresize (lwp_lwpid_htab, lwp_lwpid_htab_remove_pid, &pid); | |
d90e17a7 PA |
850 | } |
851 | ||
26cb8b7c PA |
852 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
853 | in the process. Return a pointer to the structure describing the | |
854 | new LWP. | |
855 | ||
856 | This differs from add_lwp in that we don't let the arch specific | |
857 | bits know about this new thread. Current clients of this callback | |
858 | take the opportunity to install watchpoints in the new thread, and | |
859 | we shouldn't do that for the first thread. If we're spawning a | |
860 | child ("run"), the thread executes the shell wrapper first, and we | |
861 | shouldn't touch it until it execs the program we want to debug. | |
862 | For "attach", it'd be okay to call the callback, but it's not | |
863 | necessary, because watchpoints can't yet have been inserted into | |
864 | the inferior. */ | |
d6b0e80f AC |
865 | |
866 | static struct lwp_info * | |
26cb8b7c | 867 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
868 | { |
869 | struct lwp_info *lp; | |
870 | ||
15a9e13e | 871 | gdb_assert (ptid.lwp_p ()); |
d6b0e80f | 872 | |
8d749320 | 873 | lp = XNEW (struct lwp_info); |
d6b0e80f AC |
874 | |
875 | memset (lp, 0, sizeof (struct lwp_info)); | |
876 | ||
25289eb2 | 877 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
878 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
879 | ||
880 | lp->ptid = ptid; | |
dc146f7c | 881 | lp->core = -1; |
d6b0e80f | 882 | |
774113b0 PA |
883 | /* Add to sorted-by-reverse-creation-order list. */ |
884 | lwp_list_add (lp); | |
885 | ||
886 | /* Add to keyed-by-pid htab. */ | |
887 | lwp_lwpid_htab_add_lwp (lp); | |
d6b0e80f | 888 | |
26cb8b7c PA |
889 | return lp; |
890 | } | |
891 | ||
892 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
893 | structure describing the new LWP. The LWP should already be | |
894 | stopped. */ | |
895 | ||
896 | static struct lwp_info * | |
897 | add_lwp (ptid_t ptid) | |
898 | { | |
899 | struct lwp_info *lp; | |
900 | ||
901 | lp = add_initial_lwp (ptid); | |
902 | ||
6e012a6c PA |
903 | /* Let the arch specific bits know about this new thread. Current |
904 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
905 | watchpoints in the new thread. We don't do this for the first |
906 | thread though. See add_initial_lwp. */ | |
135340af | 907 | linux_target->low_new_thread (lp); |
9f0bdab8 | 908 | |
d6b0e80f AC |
909 | return lp; |
910 | } | |
911 | ||
912 | /* Remove the LWP specified by PID from the list. */ | |
913 | ||
914 | static void | |
915 | delete_lwp (ptid_t ptid) | |
916 | { | |
774113b0 PA |
917 | struct lwp_info *lp; |
918 | void **slot; | |
919 | struct lwp_info dummy; | |
d6b0e80f | 920 | |
774113b0 PA |
921 | dummy.ptid = ptid; |
922 | slot = htab_find_slot (lwp_lwpid_htab, &dummy, NO_INSERT); | |
923 | if (slot == NULL) | |
924 | return; | |
d6b0e80f | 925 | |
774113b0 PA |
926 | lp = *(struct lwp_info **) slot; |
927 | gdb_assert (lp != NULL); | |
d6b0e80f | 928 | |
774113b0 | 929 | htab_clear_slot (lwp_lwpid_htab, slot); |
d6b0e80f | 930 | |
774113b0 PA |
931 | /* Remove from sorted-by-creation-order list. */ |
932 | lwp_list_remove (lp); | |
d6b0e80f | 933 | |
774113b0 | 934 | /* Release. */ |
7b50312a | 935 | lwp_free (lp); |
d6b0e80f AC |
936 | } |
937 | ||
938 | /* Return a pointer to the structure describing the LWP corresponding | |
939 | to PID. If no corresponding LWP could be found, return NULL. */ | |
940 | ||
941 | static struct lwp_info * | |
942 | find_lwp_pid (ptid_t ptid) | |
943 | { | |
944 | struct lwp_info *lp; | |
945 | int lwp; | |
774113b0 | 946 | struct lwp_info dummy; |
d6b0e80f | 947 | |
15a9e13e | 948 | if (ptid.lwp_p ()) |
e38504b3 | 949 | lwp = ptid.lwp (); |
d6b0e80f | 950 | else |
e99b03dc | 951 | lwp = ptid.pid (); |
d6b0e80f | 952 | |
fd79271b | 953 | dummy.ptid = ptid_t (0, lwp, 0); |
774113b0 PA |
954 | lp = (struct lwp_info *) htab_find (lwp_lwpid_htab, &dummy); |
955 | return lp; | |
d6b0e80f AC |
956 | } |
957 | ||
6d4ee8c6 | 958 | /* See nat/linux-nat.h. */ |
d6b0e80f AC |
959 | |
960 | struct lwp_info * | |
d90e17a7 | 961 | iterate_over_lwps (ptid_t filter, |
6d4ee8c6 | 962 | iterate_over_lwps_ftype callback, |
d90e17a7 | 963 | void *data) |
d6b0e80f AC |
964 | { |
965 | struct lwp_info *lp, *lpnext; | |
966 | ||
967 | for (lp = lwp_list; lp; lp = lpnext) | |
968 | { | |
969 | lpnext = lp->next; | |
d90e17a7 | 970 | |
26a57c92 | 971 | if (lp->ptid.matches (filter)) |
d90e17a7 | 972 | { |
6d4ee8c6 | 973 | if ((*callback) (lp, data) != 0) |
d90e17a7 PA |
974 | return lp; |
975 | } | |
d6b0e80f AC |
976 | } |
977 | ||
978 | return NULL; | |
979 | } | |
980 | ||
2277426b PA |
981 | /* Update our internal state when changing from one checkpoint to |
982 | another indicated by NEW_PTID. We can only switch single-threaded | |
983 | applications, so we only create one new LWP, and the previous list | |
984 | is discarded. */ | |
f973ed9c DJ |
985 | |
986 | void | |
987 | linux_nat_switch_fork (ptid_t new_ptid) | |
988 | { | |
989 | struct lwp_info *lp; | |
990 | ||
e99b03dc | 991 | purge_lwp_list (inferior_ptid.pid ()); |
2277426b | 992 | |
f973ed9c DJ |
993 | lp = add_lwp (new_ptid); |
994 | lp->stopped = 1; | |
e26af52f | 995 | |
2277426b PA |
996 | /* This changes the thread's ptid while preserving the gdb thread |
997 | num. Also changes the inferior pid, while preserving the | |
998 | inferior num. */ | |
999 | thread_change_ptid (inferior_ptid, new_ptid); | |
1000 | ||
1001 | /* We've just told GDB core that the thread changed target id, but, | |
1002 | in fact, it really is a different thread, with different register | |
1003 | contents. */ | |
1004 | registers_changed (); | |
e26af52f DJ |
1005 | } |
1006 | ||
e26af52f DJ |
1007 | /* Handle the exit of a single thread LP. */ |
1008 | ||
1009 | static void | |
1010 | exit_lwp (struct lwp_info *lp) | |
1011 | { | |
e09875d4 | 1012 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1013 | |
1014 | if (th) | |
e26af52f | 1015 | { |
17faa917 DJ |
1016 | if (print_thread_events) |
1017 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1018 | ||
00431a78 | 1019 | delete_thread (th); |
e26af52f DJ |
1020 | } |
1021 | ||
1022 | delete_lwp (lp->ptid); | |
1023 | } | |
1024 | ||
a0ef4274 DJ |
1025 | /* Wait for the LWP specified by LP, which we have just attached to. |
1026 | Returns a wait status for that LWP, to cache. */ | |
1027 | ||
1028 | static int | |
22827c51 | 1029 | linux_nat_post_attach_wait (ptid_t ptid, int *signalled) |
a0ef4274 | 1030 | { |
e38504b3 | 1031 | pid_t new_pid, pid = ptid.lwp (); |
a0ef4274 DJ |
1032 | int status; |
1033 | ||
644cebc9 | 1034 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1035 | { |
1036 | if (debug_linux_nat) | |
1037 | fprintf_unfiltered (gdb_stdlog, | |
1038 | "LNPAW: Attaching to a stopped process\n"); | |
1039 | ||
1040 | /* The process is definitely stopped. It is in a job control | |
1041 | stop, unless the kernel predates the TASK_STOPPED / | |
1042 | TASK_TRACED distinction, in which case it might be in a | |
1043 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1044 | can kill it, signal it, et cetera. | |
1045 | ||
1046 | First make sure there is a pending SIGSTOP. Since we are | |
1047 | already attached, the process can not transition from stopped | |
1048 | to running without a PTRACE_CONT; so we know this signal will | |
1049 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1050 | probably already in the queue (unless this kernel is old | |
1051 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1052 | is not an RT signal, it can only be queued once. */ | |
1053 | kill_lwp (pid, SIGSTOP); | |
1054 | ||
1055 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1056 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1057 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1058 | } | |
1059 | ||
1060 | /* Make sure the initial process is stopped. The user-level threads | |
1061 | layer might want to poke around in the inferior, and that won't | |
1062 | work if things haven't stabilized yet. */ | |
4a6ed09b | 1063 | new_pid = my_waitpid (pid, &status, __WALL); |
dacc9cb2 PP |
1064 | gdb_assert (pid == new_pid); |
1065 | ||
1066 | if (!WIFSTOPPED (status)) | |
1067 | { | |
1068 | /* The pid we tried to attach has apparently just exited. */ | |
1069 | if (debug_linux_nat) | |
1070 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1071 | pid, status_to_str (status)); | |
1072 | return status; | |
1073 | } | |
a0ef4274 DJ |
1074 | |
1075 | if (WSTOPSIG (status) != SIGSTOP) | |
1076 | { | |
1077 | *signalled = 1; | |
1078 | if (debug_linux_nat) | |
1079 | fprintf_unfiltered (gdb_stdlog, | |
1080 | "LNPAW: Received %s after attaching\n", | |
1081 | status_to_str (status)); | |
1082 | } | |
1083 | ||
1084 | return status; | |
1085 | } | |
1086 | ||
f6ac5f3d PA |
1087 | void |
1088 | linux_nat_target::create_inferior (const char *exec_file, | |
1089 | const std::string &allargs, | |
1090 | char **env, int from_tty) | |
b84876c2 | 1091 | { |
41272101 TT |
1092 | maybe_disable_address_space_randomization restore_personality |
1093 | (disable_randomization); | |
b84876c2 PA |
1094 | |
1095 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1096 | we have to mask the async mode. */ | |
1097 | ||
2455069d | 1098 | /* Make sure we report all signals during startup. */ |
f6ac5f3d | 1099 | pass_signals (0, NULL); |
2455069d | 1100 | |
f6ac5f3d | 1101 | inf_ptrace_target::create_inferior (exec_file, allargs, env, from_tty); |
b84876c2 PA |
1102 | } |
1103 | ||
8784d563 PA |
1104 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not |
1105 | already attached. Returns true if a new LWP is found, false | |
1106 | otherwise. */ | |
1107 | ||
1108 | static int | |
1109 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1110 | { | |
1111 | struct lwp_info *lp; | |
1112 | ||
1113 | /* Ignore LWPs we're already attached to. */ | |
1114 | lp = find_lwp_pid (ptid); | |
1115 | if (lp == NULL) | |
1116 | { | |
e38504b3 | 1117 | int lwpid = ptid.lwp (); |
8784d563 PA |
1118 | |
1119 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) | |
1120 | { | |
1121 | int err = errno; | |
1122 | ||
1123 | /* Be quiet if we simply raced with the thread exiting. | |
1124 | EPERM is returned if the thread's task still exists, and | |
1125 | is marked as exited or zombie, as well as other | |
1126 | conditions, so in that case, confirm the status in | |
1127 | /proc/PID/status. */ | |
1128 | if (err == ESRCH | |
1129 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1130 | { | |
1131 | if (debug_linux_nat) | |
1132 | { | |
1133 | fprintf_unfiltered (gdb_stdlog, | |
1134 | "Cannot attach to lwp %d: " | |
1135 | "thread is gone (%d: %s)\n", | |
1136 | lwpid, err, safe_strerror (err)); | |
1137 | } | |
1138 | } | |
1139 | else | |
1140 | { | |
4d9b86e1 SM |
1141 | std::string reason |
1142 | = linux_ptrace_attach_fail_reason_string (ptid, err); | |
1143 | ||
f71f0b0d | 1144 | warning (_("Cannot attach to lwp %d: %s"), |
4d9b86e1 | 1145 | lwpid, reason.c_str ()); |
8784d563 PA |
1146 | } |
1147 | } | |
1148 | else | |
1149 | { | |
1150 | if (debug_linux_nat) | |
1151 | fprintf_unfiltered (gdb_stdlog, | |
1152 | "PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1153 | target_pid_to_str (ptid)); | |
1154 | ||
1155 | lp = add_lwp (ptid); | |
8784d563 PA |
1156 | |
1157 | /* The next time we wait for this LWP we'll see a SIGSTOP as | |
1158 | PTRACE_ATTACH brings it to a halt. */ | |
1159 | lp->signalled = 1; | |
1160 | ||
1161 | /* We need to wait for a stop before being able to make the | |
1162 | next ptrace call on this LWP. */ | |
1163 | lp->must_set_ptrace_flags = 1; | |
026a9174 PA |
1164 | |
1165 | /* So that wait collects the SIGSTOP. */ | |
1166 | lp->resumed = 1; | |
1167 | ||
1168 | /* Also add the LWP to gdb's thread list, in case a | |
1169 | matching libthread_db is not found (or the process uses | |
1170 | raw clone). */ | |
1171 | add_thread (lp->ptid); | |
1172 | set_running (lp->ptid, 1); | |
1173 | set_executing (lp->ptid, 1); | |
8784d563 PA |
1174 | } |
1175 | ||
1176 | return 1; | |
1177 | } | |
1178 | return 0; | |
1179 | } | |
1180 | ||
f6ac5f3d PA |
1181 | void |
1182 | linux_nat_target::attach (const char *args, int from_tty) | |
d6b0e80f AC |
1183 | { |
1184 | struct lwp_info *lp; | |
d6b0e80f | 1185 | int status; |
af990527 | 1186 | ptid_t ptid; |
d6b0e80f | 1187 | |
2455069d | 1188 | /* Make sure we report all signals during attach. */ |
f6ac5f3d | 1189 | pass_signals (0, NULL); |
2455069d | 1190 | |
492d29ea | 1191 | TRY |
87b0bb13 | 1192 | { |
f6ac5f3d | 1193 | inf_ptrace_target::attach (args, from_tty); |
87b0bb13 | 1194 | } |
492d29ea | 1195 | CATCH (ex, RETURN_MASK_ERROR) |
87b0bb13 JK |
1196 | { |
1197 | pid_t pid = parse_pid_to_attach (args); | |
4d9b86e1 | 1198 | std::string reason = linux_ptrace_attach_fail_reason (pid); |
87b0bb13 | 1199 | |
4d9b86e1 SM |
1200 | if (!reason.empty ()) |
1201 | throw_error (ex.error, "warning: %s\n%s", reason.c_str (), ex.message); | |
7ae1a6a6 | 1202 | else |
a7b2d0fb | 1203 | throw_error (ex.error, "%s", ex.message); |
87b0bb13 | 1204 | } |
492d29ea | 1205 | END_CATCH |
d6b0e80f | 1206 | |
af990527 PA |
1207 | /* The ptrace base target adds the main thread with (pid,0,0) |
1208 | format. Decorate it with lwp info. */ | |
e99b03dc TT |
1209 | ptid = ptid_t (inferior_ptid.pid (), |
1210 | inferior_ptid.pid (), | |
fd79271b | 1211 | 0); |
af990527 PA |
1212 | thread_change_ptid (inferior_ptid, ptid); |
1213 | ||
9f0bdab8 | 1214 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1215 | lp = add_initial_lwp (ptid); |
a0ef4274 | 1216 | |
22827c51 | 1217 | status = linux_nat_post_attach_wait (lp->ptid, &lp->signalled); |
dacc9cb2 PP |
1218 | if (!WIFSTOPPED (status)) |
1219 | { | |
1220 | if (WIFEXITED (status)) | |
1221 | { | |
1222 | int exit_code = WEXITSTATUS (status); | |
1223 | ||
223ffa71 | 1224 | target_terminal::ours (); |
bc1e6c81 | 1225 | target_mourn_inferior (inferior_ptid); |
dacc9cb2 PP |
1226 | if (exit_code == 0) |
1227 | error (_("Unable to attach: program exited normally.")); | |
1228 | else | |
1229 | error (_("Unable to attach: program exited with code %d."), | |
1230 | exit_code); | |
1231 | } | |
1232 | else if (WIFSIGNALED (status)) | |
1233 | { | |
2ea28649 | 1234 | enum gdb_signal signo; |
dacc9cb2 | 1235 | |
223ffa71 | 1236 | target_terminal::ours (); |
bc1e6c81 | 1237 | target_mourn_inferior (inferior_ptid); |
dacc9cb2 | 1238 | |
2ea28649 | 1239 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1240 | error (_("Unable to attach: program terminated with signal " |
1241 | "%s, %s."), | |
2ea28649 PA |
1242 | gdb_signal_to_name (signo), |
1243 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1244 | } |
1245 | ||
1246 | internal_error (__FILE__, __LINE__, | |
1247 | _("unexpected status %d for PID %ld"), | |
e38504b3 | 1248 | status, (long) ptid.lwp ()); |
dacc9cb2 PP |
1249 | } |
1250 | ||
a0ef4274 | 1251 | lp->stopped = 1; |
9f0bdab8 | 1252 | |
a0ef4274 | 1253 | /* Save the wait status to report later. */ |
d6b0e80f | 1254 | lp->resumed = 1; |
a0ef4274 DJ |
1255 | if (debug_linux_nat) |
1256 | fprintf_unfiltered (gdb_stdlog, | |
1257 | "LNA: waitpid %ld, saving status %s\n", | |
e99b03dc | 1258 | (long) lp->ptid.pid (), status_to_str (status)); |
710151dd | 1259 | |
7feb7d06 PA |
1260 | lp->status = status; |
1261 | ||
8784d563 PA |
1262 | /* We must attach to every LWP. If /proc is mounted, use that to |
1263 | find them now. The inferior may be using raw clone instead of | |
1264 | using pthreads. But even if it is using pthreads, thread_db | |
1265 | walks structures in the inferior's address space to find the list | |
1266 | of threads/LWPs, and those structures may well be corrupted. | |
1267 | Note that once thread_db is loaded, we'll still use it to list | |
1268 | threads and associate pthread info with each LWP. */ | |
e99b03dc | 1269 | linux_proc_attach_tgid_threads (lp->ptid.pid (), |
8784d563 PA |
1270 | attach_proc_task_lwp_callback); |
1271 | ||
7feb7d06 | 1272 | if (target_can_async_p ()) |
6a3753b3 | 1273 | target_async (1); |
d6b0e80f AC |
1274 | } |
1275 | ||
ced2dffb PA |
1276 | /* Get pending signal of THREAD as a host signal number, for detaching |
1277 | purposes. This is the signal the thread last stopped for, which we | |
1278 | need to deliver to the thread when detaching, otherwise, it'd be | |
1279 | suppressed/lost. */ | |
1280 | ||
a0ef4274 | 1281 | static int |
ced2dffb | 1282 | get_detach_signal (struct lwp_info *lp) |
a0ef4274 | 1283 | { |
a493e3e2 | 1284 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1285 | |
1286 | /* If we paused threads momentarily, we may have stored pending | |
1287 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1288 | and GDB core hasn't seen any signal for those threads. | |
1289 | Otherwise, the last signal reported to the core is found in the | |
1290 | thread object's stop_signal. | |
1291 | ||
1292 | There's a corner case that isn't handled here at present. Only | |
1293 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1294 | stop_signal make sense as a real signal to pass to the inferior. | |
1295 | Some catchpoint related events, like | |
1296 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1297 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1298 | those traps are debug API (ptrace in our case) related and |
1299 | induced; the inferior wouldn't see them if it wasn't being | |
1300 | traced. Hence, we should never pass them to the inferior, even | |
1301 | when set to pass state. Since this corner case isn't handled by | |
1302 | infrun.c when proceeding with a signal, for consistency, neither | |
1303 | do we handle it here (or elsewhere in the file we check for | |
1304 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1305 | this is really a corner case. */ | |
1306 | ||
1307 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1308 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1309 | else if (lp->status) |
2ea28649 | 1310 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
00431a78 | 1311 | else |
ca2163eb PA |
1312 | { |
1313 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1314 | |
00431a78 | 1315 | if (target_is_non_stop_p () && !tp->executing) |
ca2163eb | 1316 | { |
00431a78 PA |
1317 | if (tp->suspend.waitstatus_pending_p) |
1318 | signo = tp->suspend.waitstatus.value.sig; | |
1319 | else | |
1320 | signo = tp->suspend.stop_signal; | |
1321 | } | |
1322 | else if (!target_is_non_stop_p ()) | |
1323 | { | |
1324 | struct target_waitstatus last; | |
1325 | ptid_t last_ptid; | |
1326 | ||
1327 | get_last_target_status (&last_ptid, &last); | |
e0881a8e | 1328 | |
e38504b3 | 1329 | if (lp->ptid.lwp () == last_ptid.lwp ()) |
00431a78 | 1330 | signo = tp->suspend.stop_signal; |
4c28f408 | 1331 | } |
ca2163eb | 1332 | } |
4c28f408 | 1333 | |
a493e3e2 | 1334 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1335 | { |
1336 | if (debug_linux_nat) | |
1337 | fprintf_unfiltered (gdb_stdlog, | |
1338 | "GPT: lwp %s has no pending signal\n", | |
1339 | target_pid_to_str (lp->ptid)); | |
1340 | } | |
1341 | else if (!signal_pass_state (signo)) | |
1342 | { | |
1343 | if (debug_linux_nat) | |
3e43a32a MS |
1344 | fprintf_unfiltered (gdb_stdlog, |
1345 | "GPT: lwp %s had signal %s, " | |
1346 | "but it is in no pass state\n", | |
ca2163eb | 1347 | target_pid_to_str (lp->ptid), |
2ea28649 | 1348 | gdb_signal_to_string (signo)); |
a0ef4274 | 1349 | } |
a0ef4274 | 1350 | else |
4c28f408 | 1351 | { |
ca2163eb PA |
1352 | if (debug_linux_nat) |
1353 | fprintf_unfiltered (gdb_stdlog, | |
1354 | "GPT: lwp %s has pending signal %s\n", | |
1355 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1356 | gdb_signal_to_string (signo)); |
ced2dffb PA |
1357 | |
1358 | return gdb_signal_to_host (signo); | |
4c28f408 | 1359 | } |
a0ef4274 DJ |
1360 | |
1361 | return 0; | |
1362 | } | |
1363 | ||
ced2dffb PA |
1364 | /* Detach from LP. If SIGNO_P is non-NULL, then it points to the |
1365 | signal number that should be passed to the LWP when detaching. | |
1366 | Otherwise pass any pending signal the LWP may have, if any. */ | |
1367 | ||
1368 | static void | |
1369 | detach_one_lwp (struct lwp_info *lp, int *signo_p) | |
d6b0e80f | 1370 | { |
e38504b3 | 1371 | int lwpid = lp->ptid.lwp (); |
ced2dffb PA |
1372 | int signo; |
1373 | ||
d6b0e80f AC |
1374 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); |
1375 | ||
1376 | if (debug_linux_nat && lp->status) | |
1377 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1378 | strsignal (WSTOPSIG (lp->status)), | |
1379 | target_pid_to_str (lp->ptid)); | |
1380 | ||
a0ef4274 DJ |
1381 | /* If there is a pending SIGSTOP, get rid of it. */ |
1382 | if (lp->signalled) | |
d6b0e80f | 1383 | { |
d6b0e80f AC |
1384 | if (debug_linux_nat) |
1385 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1386 | "DC: Sending SIGCONT to %s\n", |
1387 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1388 | |
ced2dffb | 1389 | kill_lwp (lwpid, SIGCONT); |
d6b0e80f | 1390 | lp->signalled = 0; |
d6b0e80f AC |
1391 | } |
1392 | ||
ced2dffb | 1393 | if (signo_p == NULL) |
d6b0e80f | 1394 | { |
a0ef4274 | 1395 | /* Pass on any pending signal for this LWP. */ |
ced2dffb PA |
1396 | signo = get_detach_signal (lp); |
1397 | } | |
1398 | else | |
1399 | signo = *signo_p; | |
a0ef4274 | 1400 | |
ced2dffb PA |
1401 | /* Preparing to resume may try to write registers, and fail if the |
1402 | lwp is zombie. If that happens, ignore the error. We'll handle | |
1403 | it below, when detach fails with ESRCH. */ | |
1404 | TRY | |
1405 | { | |
135340af | 1406 | linux_target->low_prepare_to_resume (lp); |
ced2dffb PA |
1407 | } |
1408 | CATCH (ex, RETURN_MASK_ERROR) | |
1409 | { | |
1410 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
1411 | throw_exception (ex); | |
1412 | } | |
1413 | END_CATCH | |
d6b0e80f | 1414 | |
ced2dffb PA |
1415 | if (ptrace (PTRACE_DETACH, lwpid, 0, signo) < 0) |
1416 | { | |
1417 | int save_errno = errno; | |
1418 | ||
1419 | /* We know the thread exists, so ESRCH must mean the lwp is | |
1420 | zombie. This can happen if one of the already-detached | |
1421 | threads exits the whole thread group. In that case we're | |
1422 | still attached, and must reap the lwp. */ | |
1423 | if (save_errno == ESRCH) | |
1424 | { | |
1425 | int ret, status; | |
d6b0e80f | 1426 | |
ced2dffb PA |
1427 | ret = my_waitpid (lwpid, &status, __WALL); |
1428 | if (ret == -1) | |
1429 | { | |
1430 | warning (_("Couldn't reap LWP %d while detaching: %s"), | |
1431 | lwpid, strerror (errno)); | |
1432 | } | |
1433 | else if (!WIFEXITED (status) && !WIFSIGNALED (status)) | |
1434 | { | |
1435 | warning (_("Reaping LWP %d while detaching " | |
1436 | "returned unexpected status 0x%x"), | |
1437 | lwpid, status); | |
1438 | } | |
1439 | } | |
1440 | else | |
1441 | { | |
1442 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), | |
1443 | safe_strerror (save_errno)); | |
1444 | } | |
d6b0e80f | 1445 | } |
ced2dffb PA |
1446 | else if (debug_linux_nat) |
1447 | { | |
1448 | fprintf_unfiltered (gdb_stdlog, | |
1449 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1450 | target_pid_to_str (lp->ptid), | |
1451 | strsignal (signo)); | |
1452 | } | |
1453 | ||
1454 | delete_lwp (lp->ptid); | |
1455 | } | |
d6b0e80f | 1456 | |
ced2dffb PA |
1457 | static int |
1458 | detach_callback (struct lwp_info *lp, void *data) | |
1459 | { | |
1460 | /* We don't actually detach from the thread group leader just yet. | |
1461 | If the thread group exits, we must reap the zombie clone lwps | |
1462 | before we're able to reap the leader. */ | |
e38504b3 | 1463 | if (lp->ptid.lwp () != lp->ptid.pid ()) |
ced2dffb | 1464 | detach_one_lwp (lp, NULL); |
d6b0e80f AC |
1465 | return 0; |
1466 | } | |
1467 | ||
f6ac5f3d PA |
1468 | void |
1469 | linux_nat_target::detach (inferior *inf, int from_tty) | |
d6b0e80f | 1470 | { |
d90e17a7 | 1471 | struct lwp_info *main_lwp; |
bc09b0c1 | 1472 | int pid = inf->pid; |
a0ef4274 | 1473 | |
ae5e0686 MK |
1474 | /* Don't unregister from the event loop, as there may be other |
1475 | inferiors running. */ | |
b84876c2 | 1476 | |
4c28f408 PA |
1477 | /* Stop all threads before detaching. ptrace requires that the |
1478 | thread is stopped to sucessfully detach. */ | |
f2907e49 | 1479 | iterate_over_lwps (ptid_t (pid), stop_callback, NULL); |
4c28f408 PA |
1480 | /* ... and wait until all of them have reported back that |
1481 | they're no longer running. */ | |
f2907e49 | 1482 | iterate_over_lwps (ptid_t (pid), stop_wait_callback, NULL); |
4c28f408 | 1483 | |
f2907e49 | 1484 | iterate_over_lwps (ptid_t (pid), detach_callback, NULL); |
d6b0e80f AC |
1485 | |
1486 | /* Only the initial process should be left right now. */ | |
bc09b0c1 | 1487 | gdb_assert (num_lwps (pid) == 1); |
d90e17a7 | 1488 | |
f2907e49 | 1489 | main_lwp = find_lwp_pid (ptid_t (pid)); |
d6b0e80f | 1490 | |
7a7d3353 PA |
1491 | if (forks_exist_p ()) |
1492 | { | |
1493 | /* Multi-fork case. The current inferior_ptid is being detached | |
1494 | from, but there are other viable forks to debug. Detach from | |
1495 | the current fork, and context-switch to the first | |
1496 | available. */ | |
6bd6f3b6 | 1497 | linux_fork_detach (from_tty); |
7a7d3353 PA |
1498 | } |
1499 | else | |
ced2dffb | 1500 | { |
ced2dffb PA |
1501 | target_announce_detach (from_tty); |
1502 | ||
6bd6f3b6 SM |
1503 | /* Pass on any pending signal for the last LWP. */ |
1504 | int signo = get_detach_signal (main_lwp); | |
ced2dffb PA |
1505 | |
1506 | detach_one_lwp (main_lwp, &signo); | |
1507 | ||
f6ac5f3d | 1508 | detach_success (inf); |
ced2dffb | 1509 | } |
d6b0e80f AC |
1510 | } |
1511 | ||
8a99810d PA |
1512 | /* Resume execution of the inferior process. If STEP is nonzero, |
1513 | single-step it. If SIGNAL is nonzero, give it that signal. */ | |
1514 | ||
1515 | static void | |
23f238d3 PA |
1516 | linux_resume_one_lwp_throw (struct lwp_info *lp, int step, |
1517 | enum gdb_signal signo) | |
8a99810d | 1518 | { |
8a99810d | 1519 | lp->step = step; |
9c02b525 PA |
1520 | |
1521 | /* stop_pc doubles as the PC the LWP had when it was last resumed. | |
1522 | We only presently need that if the LWP is stepped though (to | |
1523 | handle the case of stepping a breakpoint instruction). */ | |
1524 | if (step) | |
1525 | { | |
1526 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
1527 | ||
1528 | lp->stop_pc = regcache_read_pc (regcache); | |
1529 | } | |
1530 | else | |
1531 | lp->stop_pc = 0; | |
1532 | ||
135340af | 1533 | linux_target->low_prepare_to_resume (lp); |
f6ac5f3d | 1534 | linux_target->low_resume (lp->ptid, step, signo); |
23f238d3 PA |
1535 | |
1536 | /* Successfully resumed. Clear state that no longer makes sense, | |
1537 | and mark the LWP as running. Must not do this before resuming | |
1538 | otherwise if that fails other code will be confused. E.g., we'd | |
1539 | later try to stop the LWP and hang forever waiting for a stop | |
1540 | status. Note that we must not throw after this is cleared, | |
1541 | otherwise handle_zombie_lwp_error would get confused. */ | |
8a99810d | 1542 | lp->stopped = 0; |
1ad3de98 | 1543 | lp->core = -1; |
23f238d3 | 1544 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; |
8a99810d PA |
1545 | registers_changed_ptid (lp->ptid); |
1546 | } | |
1547 | ||
23f238d3 PA |
1548 | /* Called when we try to resume a stopped LWP and that errors out. If |
1549 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
1550 | or about to become), discard the error, clear any pending status | |
1551 | the LWP may have, and return true (we'll collect the exit status | |
1552 | soon enough). Otherwise, return false. */ | |
1553 | ||
1554 | static int | |
1555 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
1556 | { | |
1557 | /* If we get an error after resuming the LWP successfully, we'd | |
1558 | confuse !T state for the LWP being gone. */ | |
1559 | gdb_assert (lp->stopped); | |
1560 | ||
1561 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
1562 | because even if ptrace failed with ESRCH, the tracee may be "not | |
1563 | yet fully dead", but already refusing ptrace requests. In that | |
1564 | case the tracee has 'R (Running)' state for a little bit | |
1565 | (observed in Linux 3.18). See also the note on ESRCH in the | |
1566 | ptrace(2) man page. Instead, check whether the LWP has any state | |
1567 | other than ptrace-stopped. */ | |
1568 | ||
1569 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
e38504b3 | 1570 | if (linux_proc_pid_is_trace_stopped_nowarn (lp->ptid.lwp ()) == 0) |
23f238d3 PA |
1571 | { |
1572 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
1573 | lp->status = 0; | |
1574 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
1575 | return 1; | |
1576 | } | |
1577 | return 0; | |
1578 | } | |
1579 | ||
1580 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
1581 | disappears while we try to resume it. */ | |
1582 | ||
1583 | static void | |
1584 | linux_resume_one_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) | |
1585 | { | |
1586 | TRY | |
1587 | { | |
1588 | linux_resume_one_lwp_throw (lp, step, signo); | |
1589 | } | |
1590 | CATCH (ex, RETURN_MASK_ERROR) | |
1591 | { | |
1592 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
1593 | throw_exception (ex); | |
1594 | } | |
1595 | END_CATCH | |
1596 | } | |
1597 | ||
d6b0e80f AC |
1598 | /* Resume LP. */ |
1599 | ||
25289eb2 | 1600 | static void |
e5ef252a | 1601 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1602 | { |
25289eb2 | 1603 | if (lp->stopped) |
6c95b8df | 1604 | { |
c9657e70 | 1605 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
25289eb2 PA |
1606 | |
1607 | if (inf->vfork_child != NULL) | |
1608 | { | |
1609 | if (debug_linux_nat) | |
1610 | fprintf_unfiltered (gdb_stdlog, | |
1611 | "RC: Not resuming %s (vfork parent)\n", | |
1612 | target_pid_to_str (lp->ptid)); | |
1613 | } | |
8a99810d | 1614 | else if (!lwp_status_pending_p (lp)) |
25289eb2 PA |
1615 | { |
1616 | if (debug_linux_nat) | |
1617 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1618 | "RC: Resuming sibling %s, %s, %s\n", |
1619 | target_pid_to_str (lp->ptid), | |
1620 | (signo != GDB_SIGNAL_0 | |
1621 | ? strsignal (gdb_signal_to_host (signo)) | |
1622 | : "0"), | |
1623 | step ? "step" : "resume"); | |
25289eb2 | 1624 | |
8a99810d | 1625 | linux_resume_one_lwp (lp, step, signo); |
25289eb2 PA |
1626 | } |
1627 | else | |
1628 | { | |
1629 | if (debug_linux_nat) | |
1630 | fprintf_unfiltered (gdb_stdlog, | |
1631 | "RC: Not resuming sibling %s (has pending)\n", | |
1632 | target_pid_to_str (lp->ptid)); | |
1633 | } | |
6c95b8df | 1634 | } |
25289eb2 | 1635 | else |
d6b0e80f | 1636 | { |
d90e17a7 PA |
1637 | if (debug_linux_nat) |
1638 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1639 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1640 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1641 | } |
25289eb2 | 1642 | } |
d6b0e80f | 1643 | |
8817a6f2 PA |
1644 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1645 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1646 | |
25289eb2 | 1647 | static int |
8817a6f2 | 1648 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1649 | { |
e5ef252a PA |
1650 | enum gdb_signal signo = GDB_SIGNAL_0; |
1651 | ||
8817a6f2 PA |
1652 | if (lp == except) |
1653 | return 0; | |
1654 | ||
e5ef252a PA |
1655 | if (lp->stopped) |
1656 | { | |
1657 | struct thread_info *thread; | |
1658 | ||
1659 | thread = find_thread_ptid (lp->ptid); | |
1660 | if (thread != NULL) | |
1661 | { | |
70509625 | 1662 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1663 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1664 | } | |
1665 | } | |
1666 | ||
1667 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1668 | return 0; |
1669 | } | |
1670 | ||
1671 | static int | |
1672 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1673 | { | |
1674 | lp->resumed = 0; | |
25289eb2 | 1675 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1676 | return 0; |
1677 | } | |
1678 | ||
1679 | static int | |
1680 | resume_set_callback (struct lwp_info *lp, void *data) | |
1681 | { | |
1682 | lp->resumed = 1; | |
25289eb2 | 1683 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1684 | return 0; |
1685 | } | |
1686 | ||
f6ac5f3d PA |
1687 | void |
1688 | linux_nat_target::resume (ptid_t ptid, int step, enum gdb_signal signo) | |
d6b0e80f AC |
1689 | { |
1690 | struct lwp_info *lp; | |
d90e17a7 | 1691 | int resume_many; |
d6b0e80f | 1692 | |
76f50ad1 DJ |
1693 | if (debug_linux_nat) |
1694 | fprintf_unfiltered (gdb_stdlog, | |
1695 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1696 | step ? "step" : "resume", | |
1697 | target_pid_to_str (ptid), | |
a493e3e2 | 1698 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1699 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1700 | target_pid_to_str (inferior_ptid)); |
1701 | ||
d6b0e80f | 1702 | /* A specific PTID means `step only this process id'. */ |
d7e15655 | 1703 | resume_many = (minus_one_ptid == ptid |
0e998d96 | 1704 | || ptid.is_pid ()); |
4c28f408 | 1705 | |
e3e9f5a2 PA |
1706 | /* Mark the lwps we're resuming as resumed. */ |
1707 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1708 | |
d90e17a7 PA |
1709 | /* See if it's the current inferior that should be handled |
1710 | specially. */ | |
1711 | if (resume_many) | |
1712 | lp = find_lwp_pid (inferior_ptid); | |
1713 | else | |
1714 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1715 | gdb_assert (lp != NULL); |
d6b0e80f | 1716 | |
9f0bdab8 | 1717 | /* Remember if we're stepping. */ |
25289eb2 | 1718 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1719 | |
9f0bdab8 DJ |
1720 | /* If we have a pending wait status for this thread, there is no |
1721 | point in resuming the process. But first make sure that | |
1722 | linux_nat_wait won't preemptively handle the event - we | |
1723 | should never take this short-circuit if we are going to | |
1724 | leave LP running, since we have skipped resuming all the | |
1725 | other threads. This bit of code needs to be synchronized | |
1726 | with linux_nat_wait. */ | |
76f50ad1 | 1727 | |
9f0bdab8 DJ |
1728 | if (lp->status && WIFSTOPPED (lp->status)) |
1729 | { | |
2455069d UW |
1730 | if (!lp->step |
1731 | && WSTOPSIG (lp->status) | |
1732 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1733 | { |
9f0bdab8 DJ |
1734 | if (debug_linux_nat) |
1735 | fprintf_unfiltered (gdb_stdlog, | |
1736 | "LLR: Not short circuiting for ignored " | |
1737 | "status 0x%x\n", lp->status); | |
1738 | ||
d6b0e80f AC |
1739 | /* FIXME: What should we do if we are supposed to continue |
1740 | this thread with a signal? */ | |
a493e3e2 | 1741 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1742 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1743 | lp->status = 0; |
1744 | } | |
1745 | } | |
76f50ad1 | 1746 | |
8a99810d | 1747 | if (lwp_status_pending_p (lp)) |
9f0bdab8 DJ |
1748 | { |
1749 | /* FIXME: What should we do if we are supposed to continue | |
1750 | this thread with a signal? */ | |
a493e3e2 | 1751 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1752 | |
9f0bdab8 DJ |
1753 | if (debug_linux_nat) |
1754 | fprintf_unfiltered (gdb_stdlog, | |
1755 | "LLR: Short circuiting for status 0x%x\n", | |
1756 | lp->status); | |
d6b0e80f | 1757 | |
7feb7d06 PA |
1758 | if (target_can_async_p ()) |
1759 | { | |
6a3753b3 | 1760 | target_async (1); |
7feb7d06 PA |
1761 | /* Tell the event loop we have something to process. */ |
1762 | async_file_mark (); | |
1763 | } | |
9f0bdab8 | 1764 | return; |
d6b0e80f AC |
1765 | } |
1766 | ||
d90e17a7 | 1767 | if (resume_many) |
8817a6f2 | 1768 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 | 1769 | |
d6b0e80f AC |
1770 | if (debug_linux_nat) |
1771 | fprintf_unfiltered (gdb_stdlog, | |
1772 | "LLR: %s %s, %s (resume event thread)\n", | |
1773 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2bf6fb9d | 1774 | target_pid_to_str (lp->ptid), |
a493e3e2 | 1775 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1776 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 | 1777 | |
2bf6fb9d PA |
1778 | linux_resume_one_lwp (lp, step, signo); |
1779 | ||
b84876c2 | 1780 | if (target_can_async_p ()) |
6a3753b3 | 1781 | target_async (1); |
d6b0e80f AC |
1782 | } |
1783 | ||
c5f62d5f | 1784 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1785 | |
1786 | static int | |
1787 | kill_lwp (int lwpid, int signo) | |
1788 | { | |
4a6ed09b | 1789 | int ret; |
d6b0e80f | 1790 | |
4a6ed09b PA |
1791 | errno = 0; |
1792 | ret = syscall (__NR_tkill, lwpid, signo); | |
1793 | if (errno == ENOSYS) | |
1794 | { | |
1795 | /* If tkill fails, then we are not using nptl threads, a | |
1796 | configuration we no longer support. */ | |
1797 | perror_with_name (("tkill")); | |
1798 | } | |
1799 | return ret; | |
d6b0e80f AC |
1800 | } |
1801 | ||
ca2163eb PA |
1802 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1803 | event, check if the core is interested in it: if not, ignore the | |
1804 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1805 | syscall entry/exit status, since the ptrace event itself doesn't | |
1806 | indicate it, and report the trap to higher layers. */ | |
1807 | ||
1808 | static int | |
1809 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1810 | { | |
1811 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1812 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
00431a78 PA |
1813 | thread_info *thread = find_thread_ptid (lp->ptid); |
1814 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, thread); | |
ca2163eb PA |
1815 | |
1816 | if (stopping) | |
1817 | { | |
1818 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1819 | makes it so that the LWP reports an immediate syscall return, | |
1820 | followed by the SIGSTOP. Skip seeing that "return" using | |
1821 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1822 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1823 | entry event. If we didn't do this (and returned 0), we'd | |
1824 | leave a syscall entry pending, and our caller, by using | |
1825 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1826 | itself. Later, when the user re-resumes this LWP, we'd see | |
1827 | another syscall entry event and we'd mistake it for a return. | |
1828 | ||
1829 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1830 | (leaving immediately with LWP->signalled set, without issuing | |
1831 | a PTRACE_CONT), it would still be problematic to leave this | |
1832 | syscall enter pending, as later when the thread is resumed, | |
1833 | it would then see the same syscall exit mentioned above, | |
1834 | followed by the delayed SIGSTOP, while the syscall didn't | |
1835 | actually get to execute. It seems it would be even more | |
1836 | confusing to the user. */ | |
1837 | ||
1838 | if (debug_linux_nat) | |
1839 | fprintf_unfiltered (gdb_stdlog, | |
1840 | "LHST: ignoring syscall %d " | |
1841 | "for LWP %ld (stopping threads), " | |
1842 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1843 | syscall_number, | |
e38504b3 | 1844 | lp->ptid.lwp ()); |
ca2163eb PA |
1845 | |
1846 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
e38504b3 | 1847 | ptrace (PTRACE_CONT, lp->ptid.lwp (), 0, 0); |
8817a6f2 | 1848 | lp->stopped = 0; |
ca2163eb PA |
1849 | return 1; |
1850 | } | |
1851 | ||
bfd09d20 JS |
1852 | /* Always update the entry/return state, even if this particular |
1853 | syscall isn't interesting to the core now. In async mode, | |
1854 | the user could install a new catchpoint for this syscall | |
1855 | between syscall enter/return, and we'll need to know to | |
1856 | report a syscall return if that happens. */ | |
1857 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1858 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1859 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1860 | ||
ca2163eb PA |
1861 | if (catch_syscall_enabled ()) |
1862 | { | |
ca2163eb PA |
1863 | if (catching_syscall_number (syscall_number)) |
1864 | { | |
1865 | /* Alright, an event to report. */ | |
1866 | ourstatus->kind = lp->syscall_state; | |
1867 | ourstatus->value.syscall_number = syscall_number; | |
1868 | ||
1869 | if (debug_linux_nat) | |
1870 | fprintf_unfiltered (gdb_stdlog, | |
1871 | "LHST: stopping for %s of syscall %d" | |
1872 | " for LWP %ld\n", | |
3e43a32a MS |
1873 | lp->syscall_state |
1874 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1875 | ? "entry" : "return", |
1876 | syscall_number, | |
e38504b3 | 1877 | lp->ptid.lwp ()); |
ca2163eb PA |
1878 | return 0; |
1879 | } | |
1880 | ||
1881 | if (debug_linux_nat) | |
1882 | fprintf_unfiltered (gdb_stdlog, | |
1883 | "LHST: ignoring %s of syscall %d " | |
1884 | "for LWP %ld\n", | |
1885 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1886 | ? "entry" : "return", | |
1887 | syscall_number, | |
e38504b3 | 1888 | lp->ptid.lwp ()); |
ca2163eb PA |
1889 | } |
1890 | else | |
1891 | { | |
1892 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1893 | before on this LWP, it could happen that the user removes all | |
1894 | syscall catchpoints before we get to process this event. | |
1895 | There are two noteworthy issues here: | |
1896 | ||
1897 | - When stopped at a syscall entry event, resuming with | |
1898 | PT_STEP still resumes executing the syscall and reports a | |
1899 | syscall return. | |
1900 | ||
1901 | - Only PT_SYSCALL catches syscall enters. If we last | |
1902 | single-stepped this thread, then this event can't be a | |
1903 | syscall enter. If we last single-stepped this thread, this | |
1904 | has to be a syscall exit. | |
1905 | ||
1906 | The points above mean that the next resume, be it PT_STEP or | |
1907 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1908 | if (debug_linux_nat) | |
1909 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1910 | "LHST: caught syscall event " |
1911 | "with no syscall catchpoints." | |
ca2163eb PA |
1912 | " %d for LWP %ld, ignoring\n", |
1913 | syscall_number, | |
e38504b3 | 1914 | lp->ptid.lwp ()); |
ca2163eb PA |
1915 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1916 | } | |
1917 | ||
1918 | /* The core isn't interested in this event. For efficiency, avoid | |
1919 | stopping all threads only to have the core resume them all again. | |
1920 | Since we're not stopping threads, if we're still syscall tracing | |
1921 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1922 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1923 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1924 | ||
8a99810d | 1925 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1926 | return 1; |
1927 | } | |
1928 | ||
3d799a95 DJ |
1929 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1930 | event, we need to add the new LWP to our list (and not report the | |
1931 | trap to higher layers). This function returns non-zero if the | |
1932 | event should be ignored and we should wait again. If STOPPING is | |
1933 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1934 | |
1935 | static int | |
4dd63d48 | 1936 | linux_handle_extended_wait (struct lwp_info *lp, int status) |
d6b0e80f | 1937 | { |
e38504b3 | 1938 | int pid = lp->ptid.lwp (); |
3d799a95 | 1939 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
89a5711c | 1940 | int event = linux_ptrace_get_extended_event (status); |
d6b0e80f | 1941 | |
bfd09d20 JS |
1942 | /* All extended events we currently use are mid-syscall. Only |
1943 | PTRACE_EVENT_STOP is delivered more like a signal-stop, but | |
1944 | you have to be using PTRACE_SEIZE to get that. */ | |
1945 | lp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY; | |
1946 | ||
3d799a95 DJ |
1947 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1948 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1949 | { |
3d799a95 DJ |
1950 | unsigned long new_pid; |
1951 | int ret; | |
1952 | ||
1953 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1954 | |
3d799a95 DJ |
1955 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1956 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1957 | { | |
1958 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1959 | hits the SIGSTOP, but we're already attached. */ | |
4a6ed09b | 1960 | ret = my_waitpid (new_pid, &status, __WALL); |
3d799a95 DJ |
1961 | if (ret == -1) |
1962 | perror_with_name (_("waiting for new child")); | |
1963 | else if (ret != new_pid) | |
1964 | internal_error (__FILE__, __LINE__, | |
1965 | _("wait returned unexpected PID %d"), ret); | |
1966 | else if (!WIFSTOPPED (status)) | |
1967 | internal_error (__FILE__, __LINE__, | |
1968 | _("wait returned unexpected status 0x%x"), status); | |
1969 | } | |
1970 | ||
fd79271b | 1971 | ourstatus->value.related_pid = ptid_t (new_pid, new_pid, 0); |
3d799a95 | 1972 | |
26cb8b7c PA |
1973 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
1974 | { | |
1975 | /* The arch-specific native code may need to know about new | |
1976 | forks even if those end up never mapped to an | |
1977 | inferior. */ | |
135340af | 1978 | linux_target->low_new_fork (lp, new_pid); |
26cb8b7c PA |
1979 | } |
1980 | ||
2277426b | 1981 | if (event == PTRACE_EVENT_FORK |
e99b03dc | 1982 | && linux_fork_checkpointing_p (lp->ptid.pid ())) |
2277426b | 1983 | { |
2277426b PA |
1984 | /* Handle checkpointing by linux-fork.c here as a special |
1985 | case. We don't want the follow-fork-mode or 'catch fork' | |
1986 | to interfere with this. */ | |
1987 | ||
1988 | /* This won't actually modify the breakpoint list, but will | |
1989 | physically remove the breakpoints from the child. */ | |
fd79271b | 1990 | detach_breakpoints (ptid_t (new_pid, new_pid, 0)); |
2277426b PA |
1991 | |
1992 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
1993 | if (!find_fork_pid (new_pid)) |
1994 | add_fork (new_pid); | |
2277426b PA |
1995 | |
1996 | /* Report as spurious, so that infrun doesn't want to follow | |
1997 | this fork. We're actually doing an infcall in | |
1998 | linux-fork.c. */ | |
1999 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2000 | |
2001 | /* Report the stop to the core. */ | |
2002 | return 0; | |
2003 | } | |
2004 | ||
3d799a95 DJ |
2005 | if (event == PTRACE_EVENT_FORK) |
2006 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2007 | else if (event == PTRACE_EVENT_VFORK) | |
2008 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
4dd63d48 | 2009 | else if (event == PTRACE_EVENT_CLONE) |
3d799a95 | 2010 | { |
78768c4a JK |
2011 | struct lwp_info *new_lp; |
2012 | ||
3d799a95 | 2013 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2014 | |
3c4d7e12 PA |
2015 | if (debug_linux_nat) |
2016 | fprintf_unfiltered (gdb_stdlog, | |
2017 | "LHEW: Got clone event " | |
2018 | "from LWP %d, new child is LWP %ld\n", | |
2019 | pid, new_pid); | |
2020 | ||
e99b03dc | 2021 | new_lp = add_lwp (ptid_t (lp->ptid.pid (), new_pid, 0)); |
4c28f408 | 2022 | new_lp->stopped = 1; |
4dd63d48 | 2023 | new_lp->resumed = 1; |
d6b0e80f | 2024 | |
2db9a427 PA |
2025 | /* If the thread_db layer is active, let it record the user |
2026 | level thread id and status, and add the thread to GDB's | |
2027 | list. */ | |
2028 | if (!thread_db_notice_clone (lp->ptid, new_lp->ptid)) | |
3d799a95 | 2029 | { |
2db9a427 PA |
2030 | /* The process is not using thread_db. Add the LWP to |
2031 | GDB's list. */ | |
e38504b3 | 2032 | target_post_attach (new_lp->ptid.lwp ()); |
2db9a427 PA |
2033 | add_thread (new_lp->ptid); |
2034 | } | |
4c28f408 | 2035 | |
2ee52aa4 | 2036 | /* Even if we're stopping the thread for some reason |
4dd63d48 PA |
2037 | internal to this module, from the perspective of infrun |
2038 | and the user/frontend, this new thread is running until | |
2039 | it next reports a stop. */ | |
2ee52aa4 | 2040 | set_running (new_lp->ptid, 1); |
4dd63d48 | 2041 | set_executing (new_lp->ptid, 1); |
4c28f408 | 2042 | |
4dd63d48 | 2043 | if (WSTOPSIG (status) != SIGSTOP) |
79395f92 | 2044 | { |
4dd63d48 PA |
2045 | /* This can happen if someone starts sending signals to |
2046 | the new thread before it gets a chance to run, which | |
2047 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2048 | This is an unlikely case, and harder to handle for | |
2049 | fork / vfork than for clone, so we do not try - but | |
2050 | we handle it for clone events here. */ | |
2051 | ||
2052 | new_lp->signalled = 1; | |
2053 | ||
79395f92 PA |
2054 | /* We created NEW_LP so it cannot yet contain STATUS. */ |
2055 | gdb_assert (new_lp->status == 0); | |
2056 | ||
2057 | /* Save the wait status to report later. */ | |
2058 | if (debug_linux_nat) | |
2059 | fprintf_unfiltered (gdb_stdlog, | |
2060 | "LHEW: waitpid of new LWP %ld, " | |
2061 | "saving status %s\n", | |
e38504b3 | 2062 | (long) new_lp->ptid.lwp (), |
79395f92 PA |
2063 | status_to_str (status)); |
2064 | new_lp->status = status; | |
2065 | } | |
aa01bd36 PA |
2066 | else if (report_thread_events) |
2067 | { | |
2068 | new_lp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED; | |
2069 | new_lp->status = status; | |
2070 | } | |
79395f92 | 2071 | |
3d799a95 DJ |
2072 | return 1; |
2073 | } | |
2074 | ||
2075 | return 0; | |
d6b0e80f AC |
2076 | } |
2077 | ||
3d799a95 DJ |
2078 | if (event == PTRACE_EVENT_EXEC) |
2079 | { | |
a75724bc PA |
2080 | if (debug_linux_nat) |
2081 | fprintf_unfiltered (gdb_stdlog, | |
2082 | "LHEW: Got exec event from LWP %ld\n", | |
e38504b3 | 2083 | lp->ptid.lwp ()); |
a75724bc | 2084 | |
3d799a95 DJ |
2085 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2086 | ourstatus->value.execd_pathname | |
f6ac5f3d | 2087 | = xstrdup (linux_proc_pid_to_exec_file (pid)); |
3d799a95 | 2088 | |
8af756ef PA |
2089 | /* The thread that execed must have been resumed, but, when a |
2090 | thread execs, it changes its tid to the tgid, and the old | |
2091 | tgid thread might have not been resumed. */ | |
2092 | lp->resumed = 1; | |
6c95b8df PA |
2093 | return 0; |
2094 | } | |
2095 | ||
2096 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2097 | { | |
2098 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2099 | { |
6c95b8df | 2100 | if (debug_linux_nat) |
3e43a32a MS |
2101 | fprintf_unfiltered (gdb_stdlog, |
2102 | "LHEW: Got expected PTRACE_EVENT_" | |
2103 | "VFORK_DONE from LWP %ld: stopping\n", | |
e38504b3 | 2104 | lp->ptid.lwp ()); |
3d799a95 | 2105 | |
6c95b8df PA |
2106 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2107 | return 0; | |
3d799a95 DJ |
2108 | } |
2109 | ||
6c95b8df | 2110 | if (debug_linux_nat) |
3e43a32a MS |
2111 | fprintf_unfiltered (gdb_stdlog, |
2112 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
20ba1ce6 | 2113 | "from LWP %ld: ignoring\n", |
e38504b3 | 2114 | lp->ptid.lwp ()); |
6c95b8df | 2115 | return 1; |
3d799a95 DJ |
2116 | } |
2117 | ||
2118 | internal_error (__FILE__, __LINE__, | |
2119 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2120 | } |
2121 | ||
9c3a5d93 PA |
2122 | /* Suspend waiting for a signal. We're mostly interested in |
2123 | SIGCHLD/SIGINT. */ | |
2124 | ||
2125 | static void | |
2126 | wait_for_signal () | |
2127 | { | |
2128 | if (debug_linux_nat) | |
2129 | fprintf_unfiltered (gdb_stdlog, "linux-nat: about to sigsuspend\n"); | |
2130 | sigsuspend (&suspend_mask); | |
2131 | ||
2132 | /* If the quit flag is set, it means that the user pressed Ctrl-C | |
2133 | and we're debugging a process that is running on a separate | |
2134 | terminal, so we must forward the Ctrl-C to the inferior. (If the | |
2135 | inferior is sharing GDB's terminal, then the Ctrl-C reaches the | |
2136 | inferior directly.) We must do this here because functions that | |
2137 | need to block waiting for a signal loop forever until there's an | |
2138 | event to report before returning back to the event loop. */ | |
2139 | if (!target_terminal::is_ours ()) | |
2140 | { | |
2141 | if (check_quit_flag ()) | |
2142 | target_pass_ctrlc (); | |
2143 | } | |
2144 | } | |
2145 | ||
d6b0e80f AC |
2146 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has |
2147 | exited. */ | |
2148 | ||
2149 | static int | |
2150 | wait_lwp (struct lwp_info *lp) | |
2151 | { | |
2152 | pid_t pid; | |
432b4d03 | 2153 | int status = 0; |
d6b0e80f | 2154 | int thread_dead = 0; |
432b4d03 | 2155 | sigset_t prev_mask; |
d6b0e80f AC |
2156 | |
2157 | gdb_assert (!lp->stopped); | |
2158 | gdb_assert (lp->status == 0); | |
2159 | ||
432b4d03 JK |
2160 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2161 | block_child_signals (&prev_mask); | |
2162 | ||
2163 | for (;;) | |
d6b0e80f | 2164 | { |
e38504b3 | 2165 | pid = my_waitpid (lp->ptid.lwp (), &status, __WALL | WNOHANG); |
a9f4bb21 PA |
2166 | if (pid == -1 && errno == ECHILD) |
2167 | { | |
2168 | /* The thread has previously exited. We need to delete it | |
4a6ed09b PA |
2169 | now because if this was a non-leader thread execing, we |
2170 | won't get an exit event. See comments on exec events at | |
2171 | the top of the file. */ | |
a9f4bb21 PA |
2172 | thread_dead = 1; |
2173 | if (debug_linux_nat) | |
2174 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2175 | target_pid_to_str (lp->ptid)); | |
2176 | } | |
432b4d03 JK |
2177 | if (pid != 0) |
2178 | break; | |
2179 | ||
2180 | /* Bugs 10970, 12702. | |
2181 | Thread group leader may have exited in which case we'll lock up in | |
2182 | waitpid if there are other threads, even if they are all zombies too. | |
2183 | Basically, we're not supposed to use waitpid this way. | |
4a6ed09b PA |
2184 | tkill(pid,0) cannot be used here as it gets ESRCH for both |
2185 | for zombie and running processes. | |
432b4d03 JK |
2186 | |
2187 | As a workaround, check if we're waiting for the thread group leader and | |
2188 | if it's a zombie, and avoid calling waitpid if it is. | |
2189 | ||
2190 | This is racy, what if the tgl becomes a zombie right after we check? | |
2191 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2192 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2193 | |
e38504b3 TT |
2194 | if (lp->ptid.pid () == lp->ptid.lwp () |
2195 | && linux_proc_pid_is_zombie (lp->ptid.lwp ())) | |
d6b0e80f | 2196 | { |
d6b0e80f AC |
2197 | thread_dead = 1; |
2198 | if (debug_linux_nat) | |
432b4d03 JK |
2199 | fprintf_unfiltered (gdb_stdlog, |
2200 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2201 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2202 | break; |
d6b0e80f | 2203 | } |
432b4d03 JK |
2204 | |
2205 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2206 | get invoked despite our caller had them intentionally blocked by | |
2207 | block_child_signals. This is sensitive only to the loop of | |
2208 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2209 | again before it gets to sigsuspend so we can safely let the handlers | |
2210 | get executed here. */ | |
9c3a5d93 | 2211 | wait_for_signal (); |
432b4d03 JK |
2212 | } |
2213 | ||
2214 | restore_child_signals_mask (&prev_mask); | |
2215 | ||
d6b0e80f AC |
2216 | if (!thread_dead) |
2217 | { | |
e38504b3 | 2218 | gdb_assert (pid == lp->ptid.lwp ()); |
d6b0e80f AC |
2219 | |
2220 | if (debug_linux_nat) | |
2221 | { | |
2222 | fprintf_unfiltered (gdb_stdlog, | |
2223 | "WL: waitpid %s received %s\n", | |
2224 | target_pid_to_str (lp->ptid), | |
2225 | status_to_str (status)); | |
2226 | } | |
d6b0e80f | 2227 | |
a9f4bb21 PA |
2228 | /* Check if the thread has exited. */ |
2229 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2230 | { | |
aa01bd36 | 2231 | if (report_thread_events |
e38504b3 | 2232 | || lp->ptid.pid () == lp->ptid.lwp ()) |
69dde7dc PA |
2233 | { |
2234 | if (debug_linux_nat) | |
aa01bd36 | 2235 | fprintf_unfiltered (gdb_stdlog, "WL: LWP %d exited.\n", |
e99b03dc | 2236 | lp->ptid.pid ()); |
69dde7dc | 2237 | |
aa01bd36 | 2238 | /* If this is the leader exiting, it means the whole |
69dde7dc PA |
2239 | process is gone. Store the status to report to the |
2240 | core. Store it in lp->waitstatus, because lp->status | |
2241 | would be ambiguous (W_EXITCODE(0,0) == 0). */ | |
2242 | store_waitstatus (&lp->waitstatus, status); | |
2243 | return 0; | |
2244 | } | |
2245 | ||
a9f4bb21 PA |
2246 | thread_dead = 1; |
2247 | if (debug_linux_nat) | |
2248 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2249 | target_pid_to_str (lp->ptid)); | |
2250 | } | |
d6b0e80f AC |
2251 | } |
2252 | ||
2253 | if (thread_dead) | |
2254 | { | |
e26af52f | 2255 | exit_lwp (lp); |
d6b0e80f AC |
2256 | return 0; |
2257 | } | |
2258 | ||
2259 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2260 | lp->stopped = 1; |
d6b0e80f | 2261 | |
8784d563 PA |
2262 | if (lp->must_set_ptrace_flags) |
2263 | { | |
e99b03dc | 2264 | struct inferior *inf = find_inferior_pid (lp->ptid.pid ()); |
de0d863e | 2265 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2266 | |
e38504b3 | 2267 | linux_enable_event_reporting (lp->ptid.lwp (), options); |
8784d563 PA |
2268 | lp->must_set_ptrace_flags = 0; |
2269 | } | |
2270 | ||
ca2163eb PA |
2271 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2272 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2273 | { | |
2274 | /* No longer need the sysgood bit. The ptrace event ends up | |
2275 | recorded in lp->waitstatus if we care for it. We can carry | |
2276 | on handling the event like a regular SIGTRAP from here | |
2277 | on. */ | |
2278 | status = W_STOPCODE (SIGTRAP); | |
2279 | if (linux_handle_syscall_trap (lp, 1)) | |
2280 | return wait_lwp (lp); | |
2281 | } | |
bfd09d20 JS |
2282 | else |
2283 | { | |
2284 | /* Almost all other ptrace-stops are known to be outside of system | |
2285 | calls, with further exceptions in linux_handle_extended_wait. */ | |
2286 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
2287 | } | |
ca2163eb | 2288 | |
d6b0e80f | 2289 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
2290 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
2291 | && linux_is_extended_waitstatus (status)) | |
d6b0e80f AC |
2292 | { |
2293 | if (debug_linux_nat) | |
2294 | fprintf_unfiltered (gdb_stdlog, | |
2295 | "WL: Handling extended status 0x%06x\n", | |
2296 | status); | |
4dd63d48 | 2297 | linux_handle_extended_wait (lp, status); |
20ba1ce6 | 2298 | return 0; |
d6b0e80f AC |
2299 | } |
2300 | ||
2301 | return status; | |
2302 | } | |
2303 | ||
2304 | /* Send a SIGSTOP to LP. */ | |
2305 | ||
2306 | static int | |
2307 | stop_callback (struct lwp_info *lp, void *data) | |
2308 | { | |
2309 | if (!lp->stopped && !lp->signalled) | |
2310 | { | |
2311 | int ret; | |
2312 | ||
2313 | if (debug_linux_nat) | |
2314 | { | |
2315 | fprintf_unfiltered (gdb_stdlog, | |
2316 | "SC: kill %s **<SIGSTOP>**\n", | |
2317 | target_pid_to_str (lp->ptid)); | |
2318 | } | |
2319 | errno = 0; | |
e38504b3 | 2320 | ret = kill_lwp (lp->ptid.lwp (), SIGSTOP); |
d6b0e80f AC |
2321 | if (debug_linux_nat) |
2322 | { | |
2323 | fprintf_unfiltered (gdb_stdlog, | |
2324 | "SC: lwp kill %d %s\n", | |
2325 | ret, | |
2326 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2327 | } | |
2328 | ||
2329 | lp->signalled = 1; | |
2330 | gdb_assert (lp->status == 0); | |
2331 | } | |
2332 | ||
2333 | return 0; | |
2334 | } | |
2335 | ||
7b50312a PA |
2336 | /* Request a stop on LWP. */ |
2337 | ||
2338 | void | |
2339 | linux_stop_lwp (struct lwp_info *lwp) | |
2340 | { | |
2341 | stop_callback (lwp, NULL); | |
2342 | } | |
2343 | ||
2db9a427 PA |
2344 | /* See linux-nat.h */ |
2345 | ||
2346 | void | |
2347 | linux_stop_and_wait_all_lwps (void) | |
2348 | { | |
2349 | /* Stop all LWP's ... */ | |
2350 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); | |
2351 | ||
2352 | /* ... and wait until all of them have reported back that | |
2353 | they're no longer running. */ | |
2354 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); | |
2355 | } | |
2356 | ||
2357 | /* See linux-nat.h */ | |
2358 | ||
2359 | void | |
2360 | linux_unstop_all_lwps (void) | |
2361 | { | |
2362 | iterate_over_lwps (minus_one_ptid, | |
2363 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
2364 | } | |
2365 | ||
57380f4e | 2366 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2367 | |
2368 | static int | |
57380f4e DJ |
2369 | linux_nat_has_pending_sigint (int pid) |
2370 | { | |
2371 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2372 | |
2373 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2374 | ||
2375 | if (sigismember (&pending, SIGINT) | |
2376 | && !sigismember (&ignored, SIGINT)) | |
2377 | return 1; | |
2378 | ||
2379 | return 0; | |
2380 | } | |
2381 | ||
2382 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2383 | ||
2384 | static int | |
2385 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2386 | { |
57380f4e DJ |
2387 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2388 | flag to consume the next one. */ | |
2389 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2390 | && WSTOPSIG (lp->status) == SIGINT) | |
2391 | lp->status = 0; | |
2392 | else | |
2393 | lp->ignore_sigint = 1; | |
2394 | ||
2395 | return 0; | |
2396 | } | |
2397 | ||
2398 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2399 | This function is called after we know the LWP has stopped; if the LWP | |
2400 | stopped before the expected SIGINT was delivered, then it will never have | |
2401 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2402 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2403 | |
57380f4e DJ |
2404 | static void |
2405 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2406 | { | |
2407 | if (!lp->ignore_sigint) | |
2408 | return; | |
2409 | ||
e38504b3 | 2410 | if (!linux_nat_has_pending_sigint (lp->ptid.lwp ())) |
57380f4e DJ |
2411 | { |
2412 | if (debug_linux_nat) | |
2413 | fprintf_unfiltered (gdb_stdlog, | |
2414 | "MCIS: Clearing bogus flag for %s\n", | |
2415 | target_pid_to_str (lp->ptid)); | |
2416 | lp->ignore_sigint = 0; | |
2417 | } | |
2418 | } | |
2419 | ||
ebec9a0f PA |
2420 | /* Fetch the possible triggered data watchpoint info and store it in |
2421 | LP. | |
2422 | ||
2423 | On some archs, like x86, that use debug registers to set | |
2424 | watchpoints, it's possible that the way to know which watched | |
2425 | address trapped, is to check the register that is used to select | |
2426 | which address to watch. Problem is, between setting the watchpoint | |
2427 | and reading back which data address trapped, the user may change | |
2428 | the set of watchpoints, and, as a consequence, GDB changes the | |
2429 | debug registers in the inferior. To avoid reading back a stale | |
2430 | stopped-data-address when that happens, we cache in LP the fact | |
2431 | that a watchpoint trapped, and the corresponding data address, as | |
2432 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2433 | registers meanwhile, we have the cached data we can rely on. */ | |
2434 | ||
9c02b525 PA |
2435 | static int |
2436 | check_stopped_by_watchpoint (struct lwp_info *lp) | |
ebec9a0f | 2437 | { |
2989a365 | 2438 | scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); |
ebec9a0f PA |
2439 | inferior_ptid = lp->ptid; |
2440 | ||
f6ac5f3d | 2441 | if (linux_target->low_stopped_by_watchpoint ()) |
ebec9a0f | 2442 | { |
15c66dd6 | 2443 | lp->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; |
f6ac5f3d PA |
2444 | lp->stopped_data_address_p |
2445 | = linux_target->low_stopped_data_address (&lp->stopped_data_address); | |
ebec9a0f PA |
2446 | } |
2447 | ||
15c66dd6 | 2448 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 PA |
2449 | } |
2450 | ||
9c02b525 | 2451 | /* Returns true if the LWP had stopped for a watchpoint. */ |
ebec9a0f | 2452 | |
57810aa7 | 2453 | bool |
f6ac5f3d | 2454 | linux_nat_target::stopped_by_watchpoint () |
ebec9a0f PA |
2455 | { |
2456 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2457 | ||
2458 | gdb_assert (lp != NULL); | |
2459 | ||
15c66dd6 | 2460 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
ebec9a0f PA |
2461 | } |
2462 | ||
57810aa7 | 2463 | bool |
f6ac5f3d | 2464 | linux_nat_target::stopped_data_address (CORE_ADDR *addr_p) |
ebec9a0f PA |
2465 | { |
2466 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2467 | ||
2468 | gdb_assert (lp != NULL); | |
2469 | ||
2470 | *addr_p = lp->stopped_data_address; | |
2471 | ||
2472 | return lp->stopped_data_address_p; | |
2473 | } | |
2474 | ||
26ab7092 JK |
2475 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2476 | ||
135340af PA |
2477 | bool |
2478 | linux_nat_target::low_status_is_event (int status) | |
26ab7092 JK |
2479 | { |
2480 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2481 | } | |
2482 | ||
57380f4e DJ |
2483 | /* Wait until LP is stopped. */ |
2484 | ||
2485 | static int | |
2486 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2487 | { | |
c9657e70 | 2488 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
6c95b8df PA |
2489 | |
2490 | /* If this is a vfork parent, bail out, it is not going to report | |
2491 | any SIGSTOP until the vfork is done with. */ | |
2492 | if (inf->vfork_child != NULL) | |
2493 | return 0; | |
2494 | ||
d6b0e80f AC |
2495 | if (!lp->stopped) |
2496 | { | |
2497 | int status; | |
2498 | ||
2499 | status = wait_lwp (lp); | |
2500 | if (status == 0) | |
2501 | return 0; | |
2502 | ||
57380f4e DJ |
2503 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2504 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2505 | { |
57380f4e | 2506 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2507 | |
2508 | errno = 0; | |
e38504b3 | 2509 | ptrace (PTRACE_CONT, lp->ptid.lwp (), 0, 0); |
8817a6f2 | 2510 | lp->stopped = 0; |
d6b0e80f AC |
2511 | if (debug_linux_nat) |
2512 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2513 | "PTRACE_CONT %s, 0, 0 (%s) " |
2514 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2515 | target_pid_to_str (lp->ptid), |
2516 | errno ? safe_strerror (errno) : "OK"); | |
2517 | ||
57380f4e | 2518 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2519 | } |
2520 | ||
57380f4e DJ |
2521 | maybe_clear_ignore_sigint (lp); |
2522 | ||
d6b0e80f AC |
2523 | if (WSTOPSIG (status) != SIGSTOP) |
2524 | { | |
e5ef252a | 2525 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2526 | |
e5ef252a PA |
2527 | if (debug_linux_nat) |
2528 | fprintf_unfiltered (gdb_stdlog, | |
2529 | "SWC: Pending event %s in %s\n", | |
2530 | status_to_str ((int) status), | |
2531 | target_pid_to_str (lp->ptid)); | |
2532 | ||
2533 | /* Save the sigtrap event. */ | |
2534 | lp->status = status; | |
e5ef252a | 2535 | gdb_assert (lp->signalled); |
e7ad2f14 | 2536 | save_stop_reason (lp); |
d6b0e80f AC |
2537 | } |
2538 | else | |
2539 | { | |
7010835a | 2540 | /* We caught the SIGSTOP that we intended to catch. */ |
e5ef252a PA |
2541 | |
2542 | if (debug_linux_nat) | |
2543 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2544 | "SWC: Expected SIGSTOP caught for %s.\n", |
e5ef252a PA |
2545 | target_pid_to_str (lp->ptid)); |
2546 | ||
d6b0e80f | 2547 | lp->signalled = 0; |
7010835a AB |
2548 | |
2549 | /* If we are waiting for this stop so we can report the thread | |
2550 | stopped then we need to record this status. Otherwise, we can | |
2551 | now discard this stop event. */ | |
2552 | if (lp->last_resume_kind == resume_stop) | |
2553 | { | |
2554 | lp->status = status; | |
2555 | save_stop_reason (lp); | |
2556 | } | |
d6b0e80f AC |
2557 | } |
2558 | } | |
2559 | ||
2560 | return 0; | |
2561 | } | |
2562 | ||
9c02b525 PA |
2563 | /* Return non-zero if LP has a wait status pending. Discard the |
2564 | pending event and resume the LWP if the event that originally | |
2565 | caused the stop became uninteresting. */ | |
d6b0e80f AC |
2566 | |
2567 | static int | |
2568 | status_callback (struct lwp_info *lp, void *data) | |
2569 | { | |
2570 | /* Only report a pending wait status if we pretend that this has | |
2571 | indeed been resumed. */ | |
ca2163eb PA |
2572 | if (!lp->resumed) |
2573 | return 0; | |
2574 | ||
eb54c8bf PA |
2575 | if (!lwp_status_pending_p (lp)) |
2576 | return 0; | |
2577 | ||
15c66dd6 PA |
2578 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
2579 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
9c02b525 PA |
2580 | { |
2581 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
9c02b525 PA |
2582 | CORE_ADDR pc; |
2583 | int discard = 0; | |
2584 | ||
9c02b525 PA |
2585 | pc = regcache_read_pc (regcache); |
2586 | ||
2587 | if (pc != lp->stop_pc) | |
2588 | { | |
2589 | if (debug_linux_nat) | |
2590 | fprintf_unfiltered (gdb_stdlog, | |
2591 | "SC: PC of %s changed. was=%s, now=%s\n", | |
2592 | target_pid_to_str (lp->ptid), | |
2593 | paddress (target_gdbarch (), lp->stop_pc), | |
2594 | paddress (target_gdbarch (), pc)); | |
2595 | discard = 1; | |
2596 | } | |
faf09f01 PA |
2597 | |
2598 | #if !USE_SIGTRAP_SIGINFO | |
a01bda52 | 2599 | else if (!breakpoint_inserted_here_p (regcache->aspace (), pc)) |
9c02b525 PA |
2600 | { |
2601 | if (debug_linux_nat) | |
2602 | fprintf_unfiltered (gdb_stdlog, | |
2603 | "SC: previous breakpoint of %s, at %s gone\n", | |
2604 | target_pid_to_str (lp->ptid), | |
2605 | paddress (target_gdbarch (), lp->stop_pc)); | |
2606 | ||
2607 | discard = 1; | |
2608 | } | |
faf09f01 | 2609 | #endif |
9c02b525 PA |
2610 | |
2611 | if (discard) | |
2612 | { | |
2613 | if (debug_linux_nat) | |
2614 | fprintf_unfiltered (gdb_stdlog, | |
2615 | "SC: pending event of %s cancelled.\n", | |
2616 | target_pid_to_str (lp->ptid)); | |
2617 | ||
2618 | lp->status = 0; | |
2619 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); | |
2620 | return 0; | |
2621 | } | |
9c02b525 PA |
2622 | } |
2623 | ||
eb54c8bf | 2624 | return 1; |
d6b0e80f AC |
2625 | } |
2626 | ||
d6b0e80f AC |
2627 | /* Count the LWP's that have had events. */ |
2628 | ||
2629 | static int | |
2630 | count_events_callback (struct lwp_info *lp, void *data) | |
2631 | { | |
9a3c8263 | 2632 | int *count = (int *) data; |
d6b0e80f AC |
2633 | |
2634 | gdb_assert (count != NULL); | |
2635 | ||
9c02b525 PA |
2636 | /* Select only resumed LWPs that have an event pending. */ |
2637 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2638 | (*count)++; |
2639 | ||
2640 | return 0; | |
2641 | } | |
2642 | ||
2643 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2644 | ||
2645 | static int | |
2646 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2647 | { | |
25289eb2 PA |
2648 | if (lp->last_resume_kind == resume_step |
2649 | && lp->status != 0) | |
d6b0e80f AC |
2650 | return 1; |
2651 | else | |
2652 | return 0; | |
2653 | } | |
2654 | ||
8a99810d PA |
2655 | /* Returns true if LP has a status pending. */ |
2656 | ||
2657 | static int | |
2658 | lwp_status_pending_p (struct lwp_info *lp) | |
2659 | { | |
2660 | /* We check for lp->waitstatus in addition to lp->status, because we | |
2661 | can have pending process exits recorded in lp->status and | |
2662 | W_EXITCODE(0,0) happens to be 0. */ | |
2663 | return lp->status != 0 || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE; | |
2664 | } | |
2665 | ||
b90fc188 | 2666 | /* Select the Nth LWP that has had an event. */ |
d6b0e80f AC |
2667 | |
2668 | static int | |
2669 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2670 | { | |
9a3c8263 | 2671 | int *selector = (int *) data; |
d6b0e80f AC |
2672 | |
2673 | gdb_assert (selector != NULL); | |
2674 | ||
9c02b525 PA |
2675 | /* Select only resumed LWPs that have an event pending. */ |
2676 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2677 | if ((*selector)-- == 0) |
2678 | return 1; | |
2679 | ||
2680 | return 0; | |
2681 | } | |
2682 | ||
e7ad2f14 PA |
2683 | /* Called when the LWP stopped for a signal/trap. If it stopped for a |
2684 | trap check what caused it (breakpoint, watchpoint, trace, etc.), | |
2685 | and save the result in the LWP's stop_reason field. If it stopped | |
2686 | for a breakpoint, decrement the PC if necessary on the lwp's | |
2687 | architecture. */ | |
9c02b525 | 2688 | |
e7ad2f14 PA |
2689 | static void |
2690 | save_stop_reason (struct lwp_info *lp) | |
710151dd | 2691 | { |
e7ad2f14 PA |
2692 | struct regcache *regcache; |
2693 | struct gdbarch *gdbarch; | |
515630c5 | 2694 | CORE_ADDR pc; |
9c02b525 | 2695 | CORE_ADDR sw_bp_pc; |
faf09f01 PA |
2696 | #if USE_SIGTRAP_SIGINFO |
2697 | siginfo_t siginfo; | |
2698 | #endif | |
9c02b525 | 2699 | |
e7ad2f14 PA |
2700 | gdb_assert (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON); |
2701 | gdb_assert (lp->status != 0); | |
2702 | ||
135340af | 2703 | if (!linux_target->low_status_is_event (lp->status)) |
e7ad2f14 PA |
2704 | return; |
2705 | ||
2706 | regcache = get_thread_regcache (lp->ptid); | |
ac7936df | 2707 | gdbarch = regcache->arch (); |
e7ad2f14 | 2708 | |
9c02b525 | 2709 | pc = regcache_read_pc (regcache); |
527a273a | 2710 | sw_bp_pc = pc - gdbarch_decr_pc_after_break (gdbarch); |
515630c5 | 2711 | |
faf09f01 PA |
2712 | #if USE_SIGTRAP_SIGINFO |
2713 | if (linux_nat_get_siginfo (lp->ptid, &siginfo)) | |
2714 | { | |
2715 | if (siginfo.si_signo == SIGTRAP) | |
2716 | { | |
e7ad2f14 PA |
2717 | if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code) |
2718 | && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) | |
faf09f01 | 2719 | { |
e7ad2f14 PA |
2720 | /* The si_code is ambiguous on this arch -- check debug |
2721 | registers. */ | |
2722 | if (!check_stopped_by_watchpoint (lp)) | |
2723 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2724 | } | |
2725 | else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)) | |
2726 | { | |
2727 | /* If we determine the LWP stopped for a SW breakpoint, | |
2728 | trust it. Particularly don't check watchpoint | |
2729 | registers, because at least on s390, we'd find | |
2730 | stopped-by-watchpoint as long as there's a watchpoint | |
2731 | set. */ | |
faf09f01 | 2732 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
faf09f01 | 2733 | } |
e7ad2f14 | 2734 | else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) |
faf09f01 | 2735 | { |
e7ad2f14 PA |
2736 | /* This can indicate either a hardware breakpoint or |
2737 | hardware watchpoint. Check debug registers. */ | |
2738 | if (!check_stopped_by_watchpoint (lp)) | |
2739 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
faf09f01 | 2740 | } |
2bf6fb9d PA |
2741 | else if (siginfo.si_code == TRAP_TRACE) |
2742 | { | |
2743 | if (debug_linux_nat) | |
2744 | fprintf_unfiltered (gdb_stdlog, | |
2745 | "CSBB: %s stopped by trace\n", | |
2746 | target_pid_to_str (lp->ptid)); | |
e7ad2f14 PA |
2747 | |
2748 | /* We may have single stepped an instruction that | |
2749 | triggered a watchpoint. In that case, on some | |
2750 | architectures (such as x86), instead of TRAP_HWBKPT, | |
2751 | si_code indicates TRAP_TRACE, and we need to check | |
2752 | the debug registers separately. */ | |
2753 | check_stopped_by_watchpoint (lp); | |
2bf6fb9d | 2754 | } |
faf09f01 PA |
2755 | } |
2756 | } | |
2757 | #else | |
9c02b525 | 2758 | if ((!lp->step || lp->stop_pc == sw_bp_pc) |
a01bda52 | 2759 | && software_breakpoint_inserted_here_p (regcache->aspace (), |
9c02b525 | 2760 | sw_bp_pc)) |
710151dd | 2761 | { |
9c02b525 PA |
2762 | /* The LWP was either continued, or stepped a software |
2763 | breakpoint instruction. */ | |
e7ad2f14 PA |
2764 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
2765 | } | |
2766 | ||
a01bda52 | 2767 | if (hardware_breakpoint_inserted_here_p (regcache->aspace (), pc)) |
e7ad2f14 PA |
2768 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; |
2769 | ||
2770 | if (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON) | |
2771 | check_stopped_by_watchpoint (lp); | |
2772 | #endif | |
2773 | ||
2774 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT) | |
2775 | { | |
710151dd PA |
2776 | if (debug_linux_nat) |
2777 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2778 | "CSBB: %s stopped by software breakpoint\n", |
710151dd PA |
2779 | target_pid_to_str (lp->ptid)); |
2780 | ||
2781 | /* Back up the PC if necessary. */ | |
9c02b525 PA |
2782 | if (pc != sw_bp_pc) |
2783 | regcache_write_pc (regcache, sw_bp_pc); | |
515630c5 | 2784 | |
e7ad2f14 PA |
2785 | /* Update this so we record the correct stop PC below. */ |
2786 | pc = sw_bp_pc; | |
710151dd | 2787 | } |
e7ad2f14 | 2788 | else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) |
9c02b525 PA |
2789 | { |
2790 | if (debug_linux_nat) | |
2791 | fprintf_unfiltered (gdb_stdlog, | |
e7ad2f14 PA |
2792 | "CSBB: %s stopped by hardware breakpoint\n", |
2793 | target_pid_to_str (lp->ptid)); | |
2794 | } | |
2795 | else if (lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT) | |
2796 | { | |
2797 | if (debug_linux_nat) | |
2798 | fprintf_unfiltered (gdb_stdlog, | |
2799 | "CSBB: %s stopped by hardware watchpoint\n", | |
9c02b525 | 2800 | target_pid_to_str (lp->ptid)); |
9c02b525 | 2801 | } |
d6b0e80f | 2802 | |
e7ad2f14 | 2803 | lp->stop_pc = pc; |
d6b0e80f AC |
2804 | } |
2805 | ||
faf09f01 PA |
2806 | |
2807 | /* Returns true if the LWP had stopped for a software breakpoint. */ | |
2808 | ||
57810aa7 | 2809 | bool |
f6ac5f3d | 2810 | linux_nat_target::stopped_by_sw_breakpoint () |
faf09f01 PA |
2811 | { |
2812 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2813 | ||
2814 | gdb_assert (lp != NULL); | |
2815 | ||
2816 | return lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2817 | } | |
2818 | ||
2819 | /* Implement the supports_stopped_by_sw_breakpoint method. */ | |
2820 | ||
57810aa7 | 2821 | bool |
f6ac5f3d | 2822 | linux_nat_target::supports_stopped_by_sw_breakpoint () |
faf09f01 PA |
2823 | { |
2824 | return USE_SIGTRAP_SIGINFO; | |
2825 | } | |
2826 | ||
2827 | /* Returns true if the LWP had stopped for a hardware | |
2828 | breakpoint/watchpoint. */ | |
2829 | ||
57810aa7 | 2830 | bool |
f6ac5f3d | 2831 | linux_nat_target::stopped_by_hw_breakpoint () |
faf09f01 PA |
2832 | { |
2833 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2834 | ||
2835 | gdb_assert (lp != NULL); | |
2836 | ||
2837 | return lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2838 | } | |
2839 | ||
2840 | /* Implement the supports_stopped_by_hw_breakpoint method. */ | |
2841 | ||
57810aa7 | 2842 | bool |
f6ac5f3d | 2843 | linux_nat_target::supports_stopped_by_hw_breakpoint () |
faf09f01 PA |
2844 | { |
2845 | return USE_SIGTRAP_SIGINFO; | |
2846 | } | |
2847 | ||
d6b0e80f AC |
2848 | /* Select one LWP out of those that have events pending. */ |
2849 | ||
2850 | static void | |
d90e17a7 | 2851 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2852 | { |
2853 | int num_events = 0; | |
2854 | int random_selector; | |
9c02b525 | 2855 | struct lwp_info *event_lp = NULL; |
d6b0e80f | 2856 | |
ac264b3b | 2857 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2858 | (*orig_lp)->status = *status; |
2859 | ||
9c02b525 PA |
2860 | /* In all-stop, give preference to the LWP that is being |
2861 | single-stepped. There will be at most one, and it will be the | |
2862 | LWP that the core is most interested in. If we didn't do this, | |
2863 | then we'd have to handle pending step SIGTRAPs somehow in case | |
2864 | the core later continues the previously-stepped thread, as | |
2865 | otherwise we'd report the pending SIGTRAP then, and the core, not | |
2866 | having stepped the thread, wouldn't understand what the trap was | |
2867 | for, and therefore would report it to the user as a random | |
2868 | signal. */ | |
fbea99ea | 2869 | if (!target_is_non_stop_p ()) |
d6b0e80f | 2870 | { |
9c02b525 PA |
2871 | event_lp = iterate_over_lwps (filter, |
2872 | select_singlestep_lwp_callback, NULL); | |
2873 | if (event_lp != NULL) | |
2874 | { | |
2875 | if (debug_linux_nat) | |
2876 | fprintf_unfiltered (gdb_stdlog, | |
2877 | "SEL: Select single-step %s\n", | |
2878 | target_pid_to_str (event_lp->ptid)); | |
2879 | } | |
d6b0e80f | 2880 | } |
9c02b525 PA |
2881 | |
2882 | if (event_lp == NULL) | |
d6b0e80f | 2883 | { |
9c02b525 | 2884 | /* Pick one at random, out of those which have had events. */ |
d6b0e80f | 2885 | |
9c02b525 | 2886 | /* First see how many events we have. */ |
d90e17a7 | 2887 | iterate_over_lwps (filter, count_events_callback, &num_events); |
8bf3b159 | 2888 | gdb_assert (num_events > 0); |
d6b0e80f | 2889 | |
9c02b525 PA |
2890 | /* Now randomly pick a LWP out of those that have had |
2891 | events. */ | |
d6b0e80f AC |
2892 | random_selector = (int) |
2893 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2894 | ||
2895 | if (debug_linux_nat && num_events > 1) | |
2896 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2897 | "SEL: Found %d events, selecting #%d\n", |
d6b0e80f AC |
2898 | num_events, random_selector); |
2899 | ||
d90e17a7 PA |
2900 | event_lp = iterate_over_lwps (filter, |
2901 | select_event_lwp_callback, | |
d6b0e80f AC |
2902 | &random_selector); |
2903 | } | |
2904 | ||
2905 | if (event_lp != NULL) | |
2906 | { | |
2907 | /* Switch the event LWP. */ | |
2908 | *orig_lp = event_lp; | |
2909 | *status = event_lp->status; | |
2910 | } | |
2911 | ||
2912 | /* Flush the wait status for the event LWP. */ | |
2913 | (*orig_lp)->status = 0; | |
2914 | } | |
2915 | ||
2916 | /* Return non-zero if LP has been resumed. */ | |
2917 | ||
2918 | static int | |
2919 | resumed_callback (struct lwp_info *lp, void *data) | |
2920 | { | |
2921 | return lp->resumed; | |
2922 | } | |
2923 | ||
02f3fc28 | 2924 | /* Check if we should go on and pass this event to common code. |
9c02b525 | 2925 | Return the affected lwp if we are, or NULL otherwise. */ |
12d9289a | 2926 | |
02f3fc28 | 2927 | static struct lwp_info * |
9c02b525 | 2928 | linux_nat_filter_event (int lwpid, int status) |
02f3fc28 PA |
2929 | { |
2930 | struct lwp_info *lp; | |
89a5711c | 2931 | int event = linux_ptrace_get_extended_event (status); |
02f3fc28 | 2932 | |
f2907e49 | 2933 | lp = find_lwp_pid (ptid_t (lwpid)); |
02f3fc28 PA |
2934 | |
2935 | /* Check for stop events reported by a process we didn't already | |
2936 | know about - anything not already in our LWP list. | |
2937 | ||
2938 | If we're expecting to receive stopped processes after | |
2939 | fork, vfork, and clone events, then we'll just add the | |
2940 | new one to our list and go back to waiting for the event | |
2941 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2942 | from waitpid before or after the event is. |
2943 | ||
2944 | But note the case of a non-leader thread exec'ing after the | |
2945 | leader having exited, and gone from our lists. The non-leader | |
2946 | thread changes its tid to the tgid. */ | |
2947 | ||
2948 | if (WIFSTOPPED (status) && lp == NULL | |
89a5711c | 2949 | && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC)) |
0e5bf2a8 PA |
2950 | { |
2951 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2952 | if (debug_linux_nat) | |
2953 | fprintf_unfiltered (gdb_stdlog, | |
2954 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2955 | lwpid); | |
2956 | ||
fd79271b | 2957 | lp = add_lwp (ptid_t (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2958 | lp->stopped = 1; |
2959 | lp->resumed = 1; | |
2960 | add_thread (lp->ptid); | |
2961 | } | |
2962 | ||
02f3fc28 PA |
2963 | if (WIFSTOPPED (status) && !lp) |
2964 | { | |
3b27ef47 PA |
2965 | if (debug_linux_nat) |
2966 | fprintf_unfiltered (gdb_stdlog, | |
2967 | "LHEW: saving LWP %ld status %s in stopped_pids list\n", | |
2968 | (long) lwpid, status_to_str (status)); | |
84636d28 | 2969 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2970 | return NULL; |
2971 | } | |
2972 | ||
2973 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2974 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2975 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2976 | exits. */ |
2977 | if (!WIFSTOPPED (status) && !lp) | |
2978 | return NULL; | |
2979 | ||
8817a6f2 PA |
2980 | /* This LWP is stopped now. (And if dead, this prevents it from |
2981 | ever being continued.) */ | |
2982 | lp->stopped = 1; | |
2983 | ||
8784d563 PA |
2984 | if (WIFSTOPPED (status) && lp->must_set_ptrace_flags) |
2985 | { | |
e99b03dc | 2986 | struct inferior *inf = find_inferior_pid (lp->ptid.pid ()); |
de0d863e | 2987 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2988 | |
e38504b3 | 2989 | linux_enable_event_reporting (lp->ptid.lwp (), options); |
8784d563 PA |
2990 | lp->must_set_ptrace_flags = 0; |
2991 | } | |
2992 | ||
ca2163eb PA |
2993 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2994 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2995 | { | |
2996 | /* No longer need the sysgood bit. The ptrace event ends up | |
2997 | recorded in lp->waitstatus if we care for it. We can carry | |
2998 | on handling the event like a regular SIGTRAP from here | |
2999 | on. */ | |
3000 | status = W_STOPCODE (SIGTRAP); | |
3001 | if (linux_handle_syscall_trap (lp, 0)) | |
3002 | return NULL; | |
3003 | } | |
bfd09d20 JS |
3004 | else |
3005 | { | |
3006 | /* Almost all other ptrace-stops are known to be outside of system | |
3007 | calls, with further exceptions in linux_handle_extended_wait. */ | |
3008 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
3009 | } | |
02f3fc28 | 3010 | |
ca2163eb | 3011 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
3012 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
3013 | && linux_is_extended_waitstatus (status)) | |
02f3fc28 PA |
3014 | { |
3015 | if (debug_linux_nat) | |
3016 | fprintf_unfiltered (gdb_stdlog, | |
3017 | "LLW: Handling extended status 0x%06x\n", | |
3018 | status); | |
4dd63d48 | 3019 | if (linux_handle_extended_wait (lp, status)) |
02f3fc28 PA |
3020 | return NULL; |
3021 | } | |
3022 | ||
3023 | /* Check if the thread has exited. */ | |
9c02b525 PA |
3024 | if (WIFEXITED (status) || WIFSIGNALED (status)) |
3025 | { | |
aa01bd36 | 3026 | if (!report_thread_events |
e99b03dc | 3027 | && num_lwps (lp->ptid.pid ()) > 1) |
02f3fc28 | 3028 | { |
9c02b525 PA |
3029 | if (debug_linux_nat) |
3030 | fprintf_unfiltered (gdb_stdlog, | |
3031 | "LLW: %s exited.\n", | |
3032 | target_pid_to_str (lp->ptid)); | |
3033 | ||
4a6ed09b PA |
3034 | /* If there is at least one more LWP, then the exit signal |
3035 | was not the end of the debugged application and should be | |
3036 | ignored. */ | |
3037 | exit_lwp (lp); | |
3038 | return NULL; | |
02f3fc28 PA |
3039 | } |
3040 | ||
77598427 PA |
3041 | /* Note that even if the leader was ptrace-stopped, it can still |
3042 | exit, if e.g., some other thread brings down the whole | |
3043 | process (calls `exit'). So don't assert that the lwp is | |
3044 | resumed. */ | |
02f3fc28 PA |
3045 | if (debug_linux_nat) |
3046 | fprintf_unfiltered (gdb_stdlog, | |
aa01bd36 | 3047 | "LWP %ld exited (resumed=%d)\n", |
e38504b3 | 3048 | lp->ptid.lwp (), lp->resumed); |
02f3fc28 | 3049 | |
9c02b525 PA |
3050 | /* Dead LWP's aren't expected to reported a pending sigstop. */ |
3051 | lp->signalled = 0; | |
3052 | ||
3053 | /* Store the pending event in the waitstatus, because | |
3054 | W_EXITCODE(0,0) == 0. */ | |
3055 | store_waitstatus (&lp->waitstatus, status); | |
3056 | return lp; | |
02f3fc28 PA |
3057 | } |
3058 | ||
02f3fc28 PA |
3059 | /* Make sure we don't report a SIGSTOP that we sent ourselves in |
3060 | an attempt to stop an LWP. */ | |
3061 | if (lp->signalled | |
3062 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3063 | { | |
02f3fc28 PA |
3064 | lp->signalled = 0; |
3065 | ||
2bf6fb9d | 3066 | if (lp->last_resume_kind == resume_stop) |
25289eb2 | 3067 | { |
2bf6fb9d PA |
3068 | if (debug_linux_nat) |
3069 | fprintf_unfiltered (gdb_stdlog, | |
3070 | "LLW: resume_stop SIGSTOP caught for %s.\n", | |
3071 | target_pid_to_str (lp->ptid)); | |
3072 | } | |
3073 | else | |
3074 | { | |
3075 | /* This is a delayed SIGSTOP. Filter out the event. */ | |
02f3fc28 | 3076 | |
25289eb2 PA |
3077 | if (debug_linux_nat) |
3078 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 3079 | "LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n", |
25289eb2 PA |
3080 | lp->step ? |
3081 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3082 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3083 | |
2bf6fb9d | 3084 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
25289eb2 | 3085 | gdb_assert (lp->resumed); |
25289eb2 PA |
3086 | return NULL; |
3087 | } | |
02f3fc28 PA |
3088 | } |
3089 | ||
57380f4e DJ |
3090 | /* Make sure we don't report a SIGINT that we have already displayed |
3091 | for another thread. */ | |
3092 | if (lp->ignore_sigint | |
3093 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3094 | { | |
3095 | if (debug_linux_nat) | |
3096 | fprintf_unfiltered (gdb_stdlog, | |
3097 | "LLW: Delayed SIGINT caught for %s.\n", | |
3098 | target_pid_to_str (lp->ptid)); | |
3099 | ||
3100 | /* This is a delayed SIGINT. */ | |
3101 | lp->ignore_sigint = 0; | |
3102 | ||
8a99810d | 3103 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3104 | if (debug_linux_nat) |
3105 | fprintf_unfiltered (gdb_stdlog, | |
3106 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3107 | lp->step ? | |
3108 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3109 | target_pid_to_str (lp->ptid)); | |
57380f4e DJ |
3110 | gdb_assert (lp->resumed); |
3111 | ||
3112 | /* Discard the event. */ | |
3113 | return NULL; | |
3114 | } | |
3115 | ||
9c02b525 PA |
3116 | /* Don't report signals that GDB isn't interested in, such as |
3117 | signals that are neither printed nor stopped upon. Stopping all | |
3118 | threads can be a bit time-consuming so if we want decent | |
3119 | performance with heavily multi-threaded programs, especially when | |
3120 | they're using a high frequency timer, we'd better avoid it if we | |
3121 | can. */ | |
3122 | if (WIFSTOPPED (status)) | |
3123 | { | |
3124 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); | |
3125 | ||
fbea99ea | 3126 | if (!target_is_non_stop_p ()) |
9c02b525 PA |
3127 | { |
3128 | /* Only do the below in all-stop, as we currently use SIGSTOP | |
3129 | to implement target_stop (see linux_nat_stop) in | |
3130 | non-stop. */ | |
3131 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) | |
3132 | { | |
3133 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3134 | forwarded to the entire process group, that is, all LWPs | |
3135 | will receive it - unless they're using CLONE_THREAD to | |
3136 | share signals. Since we only want to report it once, we | |
3137 | mark it as ignored for all LWPs except this one. */ | |
e99b03dc | 3138 | iterate_over_lwps (ptid_t (lp->ptid.pid ()), |
9c02b525 PA |
3139 | set_ignore_sigint, NULL); |
3140 | lp->ignore_sigint = 0; | |
3141 | } | |
3142 | else | |
3143 | maybe_clear_ignore_sigint (lp); | |
3144 | } | |
3145 | ||
3146 | /* When using hardware single-step, we need to report every signal. | |
c9587f88 AT |
3147 | Otherwise, signals in pass_mask may be short-circuited |
3148 | except signals that might be caused by a breakpoint. */ | |
9c02b525 | 3149 | if (!lp->step |
c9587f88 AT |
3150 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)) |
3151 | && !linux_wstatus_maybe_breakpoint (status)) | |
9c02b525 PA |
3152 | { |
3153 | linux_resume_one_lwp (lp, lp->step, signo); | |
3154 | if (debug_linux_nat) | |
3155 | fprintf_unfiltered (gdb_stdlog, | |
3156 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3157 | lp->step ? | |
3158 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3159 | target_pid_to_str (lp->ptid), | |
3160 | (signo != GDB_SIGNAL_0 | |
3161 | ? strsignal (gdb_signal_to_host (signo)) | |
3162 | : "0")); | |
3163 | return NULL; | |
3164 | } | |
3165 | } | |
3166 | ||
02f3fc28 PA |
3167 | /* An interesting event. */ |
3168 | gdb_assert (lp); | |
ca2163eb | 3169 | lp->status = status; |
e7ad2f14 | 3170 | save_stop_reason (lp); |
02f3fc28 PA |
3171 | return lp; |
3172 | } | |
3173 | ||
0e5bf2a8 PA |
3174 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3175 | their exits until all other threads in the group have exited. */ | |
3176 | ||
3177 | static void | |
3178 | check_zombie_leaders (void) | |
3179 | { | |
08036331 | 3180 | for (inferior *inf : all_inferiors ()) |
0e5bf2a8 PA |
3181 | { |
3182 | struct lwp_info *leader_lp; | |
3183 | ||
3184 | if (inf->pid == 0) | |
3185 | continue; | |
3186 | ||
f2907e49 | 3187 | leader_lp = find_lwp_pid (ptid_t (inf->pid)); |
0e5bf2a8 PA |
3188 | if (leader_lp != NULL |
3189 | /* Check if there are other threads in the group, as we may | |
3190 | have raced with the inferior simply exiting. */ | |
3191 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3192 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3193 | { |
3194 | if (debug_linux_nat) | |
3195 | fprintf_unfiltered (gdb_stdlog, | |
3196 | "CZL: Thread group leader %d zombie " | |
3197 | "(it exited, or another thread execd).\n", | |
3198 | inf->pid); | |
3199 | ||
3200 | /* A leader zombie can mean one of two things: | |
3201 | ||
3202 | - It exited, and there's an exit status pending | |
3203 | available, or only the leader exited (not the whole | |
3204 | program). In the latter case, we can't waitpid the | |
3205 | leader's exit status until all other threads are gone. | |
3206 | ||
3207 | - There are 3 or more threads in the group, and a thread | |
4a6ed09b PA |
3208 | other than the leader exec'd. See comments on exec |
3209 | events at the top of the file. We could try | |
0e5bf2a8 PA |
3210 | distinguishing the exit and exec cases, by waiting once |
3211 | more, and seeing if something comes out, but it doesn't | |
3212 | sound useful. The previous leader _does_ go away, and | |
3213 | we'll re-add the new one once we see the exec event | |
3214 | (which is just the same as what would happen if the | |
3215 | previous leader did exit voluntarily before some other | |
3216 | thread execs). */ | |
3217 | ||
3218 | if (debug_linux_nat) | |
3219 | fprintf_unfiltered (gdb_stdlog, | |
3220 | "CZL: Thread group leader %d vanished.\n", | |
3221 | inf->pid); | |
3222 | exit_lwp (leader_lp); | |
3223 | } | |
3224 | } | |
3225 | } | |
3226 | ||
aa01bd36 PA |
3227 | /* Convenience function that is called when the kernel reports an exit |
3228 | event. This decides whether to report the event to GDB as a | |
3229 | process exit event, a thread exit event, or to suppress the | |
3230 | event. */ | |
3231 | ||
3232 | static ptid_t | |
3233 | filter_exit_event (struct lwp_info *event_child, | |
3234 | struct target_waitstatus *ourstatus) | |
3235 | { | |
3236 | ptid_t ptid = event_child->ptid; | |
3237 | ||
e99b03dc | 3238 | if (num_lwps (ptid.pid ()) > 1) |
aa01bd36 PA |
3239 | { |
3240 | if (report_thread_events) | |
3241 | ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED; | |
3242 | else | |
3243 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3244 | ||
3245 | exit_lwp (event_child); | |
3246 | } | |
3247 | ||
3248 | return ptid; | |
3249 | } | |
3250 | ||
d6b0e80f | 3251 | static ptid_t |
f6ac5f3d | 3252 | linux_nat_wait_1 (ptid_t ptid, struct target_waitstatus *ourstatus, |
47608cb1 | 3253 | int target_options) |
d6b0e80f | 3254 | { |
fc9b8e47 | 3255 | sigset_t prev_mask; |
4b60df3d | 3256 | enum resume_kind last_resume_kind; |
12d9289a | 3257 | struct lwp_info *lp; |
12d9289a | 3258 | int status; |
d6b0e80f | 3259 | |
01124a23 | 3260 | if (debug_linux_nat) |
b84876c2 PA |
3261 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3262 | ||
f973ed9c DJ |
3263 | /* The first time we get here after starting a new inferior, we may |
3264 | not have added it to the LWP list yet - this is the earliest | |
3265 | moment at which we know its PID. */ | |
0e998d96 | 3266 | if (inferior_ptid.is_pid ()) |
f973ed9c | 3267 | { |
27c9d204 PA |
3268 | /* Upgrade the main thread's ptid. */ |
3269 | thread_change_ptid (inferior_ptid, | |
e99b03dc TT |
3270 | ptid_t (inferior_ptid.pid (), |
3271 | inferior_ptid.pid (), 0)); | |
27c9d204 | 3272 | |
26cb8b7c | 3273 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3274 | lp->resumed = 1; |
3275 | } | |
3276 | ||
12696c10 | 3277 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3278 | block_child_signals (&prev_mask); |
d6b0e80f | 3279 | |
d6b0e80f | 3280 | /* First check if there is a LWP with a wait status pending. */ |
8a99810d PA |
3281 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3282 | if (lp != NULL) | |
d6b0e80f AC |
3283 | { |
3284 | if (debug_linux_nat) | |
d6b0e80f AC |
3285 | fprintf_unfiltered (gdb_stdlog, |
3286 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3287 | status_to_str (lp->status), |
d6b0e80f | 3288 | target_pid_to_str (lp->ptid)); |
d6b0e80f AC |
3289 | } |
3290 | ||
9c02b525 PA |
3291 | /* But if we don't find a pending event, we'll have to wait. Always |
3292 | pull all events out of the kernel. We'll randomly select an | |
3293 | event LWP out of all that have events, to prevent starvation. */ | |
7feb7d06 | 3294 | |
d90e17a7 | 3295 | while (lp == NULL) |
d6b0e80f AC |
3296 | { |
3297 | pid_t lwpid; | |
3298 | ||
0e5bf2a8 PA |
3299 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3300 | quirks: | |
3301 | ||
3302 | - If the thread group leader exits while other threads in the | |
3303 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3304 | waitpid won't return an exit status until the other threads | |
3305 | in the group are reapped. | |
3306 | ||
3307 | - When a non-leader thread execs, that thread just vanishes | |
3308 | without reporting an exit (so we'd hang if we waited for it | |
3309 | explicitly in that case). The exec event is reported to | |
3310 | the TGID pid. */ | |
3311 | ||
3312 | errno = 0; | |
4a6ed09b | 3313 | lwpid = my_waitpid (-1, &status, __WALL | WNOHANG); |
0e5bf2a8 PA |
3314 | |
3315 | if (debug_linux_nat) | |
3316 | fprintf_unfiltered (gdb_stdlog, | |
3317 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3318 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3319 | |
d6b0e80f AC |
3320 | if (lwpid > 0) |
3321 | { | |
d6b0e80f AC |
3322 | if (debug_linux_nat) |
3323 | { | |
3324 | fprintf_unfiltered (gdb_stdlog, | |
3325 | "LLW: waitpid %ld received %s\n", | |
3326 | (long) lwpid, status_to_str (status)); | |
3327 | } | |
3328 | ||
9c02b525 | 3329 | linux_nat_filter_event (lwpid, status); |
0e5bf2a8 PA |
3330 | /* Retry until nothing comes out of waitpid. A single |
3331 | SIGCHLD can indicate more than one child stopped. */ | |
3332 | continue; | |
d6b0e80f AC |
3333 | } |
3334 | ||
20ba1ce6 PA |
3335 | /* Now that we've pulled all events out of the kernel, resume |
3336 | LWPs that don't have an interesting event to report. */ | |
3337 | iterate_over_lwps (minus_one_ptid, | |
3338 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
3339 | ||
3340 | /* ... and find an LWP with a status to report to the core, if | |
3341 | any. */ | |
9c02b525 PA |
3342 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3343 | if (lp != NULL) | |
3344 | break; | |
3345 | ||
0e5bf2a8 PA |
3346 | /* Check for zombie thread group leaders. Those can't be reaped |
3347 | until all other threads in the thread group are. */ | |
3348 | check_zombie_leaders (); | |
d6b0e80f | 3349 | |
0e5bf2a8 PA |
3350 | /* If there are no resumed children left, bail. We'd be stuck |
3351 | forever in the sigsuspend call below otherwise. */ | |
3352 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3353 | { | |
3354 | if (debug_linux_nat) | |
3355 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3356 | |
0e5bf2a8 | 3357 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3358 | |
0e5bf2a8 PA |
3359 | restore_child_signals_mask (&prev_mask); |
3360 | return minus_one_ptid; | |
d6b0e80f | 3361 | } |
28736962 | 3362 | |
0e5bf2a8 PA |
3363 | /* No interesting event to report to the core. */ |
3364 | ||
3365 | if (target_options & TARGET_WNOHANG) | |
3366 | { | |
01124a23 | 3367 | if (debug_linux_nat) |
28736962 PA |
3368 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3369 | ||
0e5bf2a8 | 3370 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3371 | restore_child_signals_mask (&prev_mask); |
3372 | return minus_one_ptid; | |
3373 | } | |
d6b0e80f AC |
3374 | |
3375 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3376 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3377 | |
3378 | /* Block until we get an event reported with SIGCHLD. */ | |
9c3a5d93 | 3379 | wait_for_signal (); |
d6b0e80f AC |
3380 | } |
3381 | ||
d6b0e80f AC |
3382 | gdb_assert (lp); |
3383 | ||
ca2163eb PA |
3384 | status = lp->status; |
3385 | lp->status = 0; | |
3386 | ||
fbea99ea | 3387 | if (!target_is_non_stop_p ()) |
4c28f408 PA |
3388 | { |
3389 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3390 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3391 | |
3392 | /* ... and wait until all of them have reported back that | |
3393 | they're no longer running. */ | |
d90e17a7 | 3394 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
9c02b525 PA |
3395 | } |
3396 | ||
3397 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
3398 | among those that have had events. Giving equal priority to all | |
3399 | LWPs that have had events helps prevent starvation. */ | |
d7e15655 | 3400 | if (ptid == minus_one_ptid || ptid.is_pid ()) |
9c02b525 PA |
3401 | select_event_lwp (ptid, &lp, &status); |
3402 | ||
3403 | gdb_assert (lp != NULL); | |
3404 | ||
3405 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
faf09f01 PA |
3406 | it was a software breakpoint, and we can't reliably support the |
3407 | "stopped by software breakpoint" stop reason. */ | |
3408 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3409 | && !USE_SIGTRAP_SIGINFO) | |
9c02b525 PA |
3410 | { |
3411 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
ac7936df | 3412 | struct gdbarch *gdbarch = regcache->arch (); |
527a273a | 3413 | int decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
4c28f408 | 3414 | |
9c02b525 PA |
3415 | if (decr_pc != 0) |
3416 | { | |
3417 | CORE_ADDR pc; | |
d6b0e80f | 3418 | |
9c02b525 PA |
3419 | pc = regcache_read_pc (regcache); |
3420 | regcache_write_pc (regcache, pc + decr_pc); | |
3421 | } | |
3422 | } | |
e3e9f5a2 | 3423 | |
9c02b525 PA |
3424 | /* We'll need this to determine whether to report a SIGSTOP as |
3425 | GDB_SIGNAL_0. Need to take a copy because resume_clear_callback | |
3426 | clears it. */ | |
3427 | last_resume_kind = lp->last_resume_kind; | |
4b60df3d | 3428 | |
fbea99ea | 3429 | if (!target_is_non_stop_p ()) |
9c02b525 | 3430 | { |
e3e9f5a2 PA |
3431 | /* In all-stop, from the core's perspective, all LWPs are now |
3432 | stopped until a new resume action is sent over. */ | |
3433 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3434 | } | |
3435 | else | |
25289eb2 | 3436 | { |
4b60df3d | 3437 | resume_clear_callback (lp, NULL); |
25289eb2 | 3438 | } |
d6b0e80f | 3439 | |
135340af | 3440 | if (linux_target->low_status_is_event (status)) |
d6b0e80f | 3441 | { |
d6b0e80f AC |
3442 | if (debug_linux_nat) |
3443 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3444 | "LLW: trap ptid is %s.\n", |
3445 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3446 | } |
d6b0e80f AC |
3447 | |
3448 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3449 | { | |
3450 | *ourstatus = lp->waitstatus; | |
3451 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3452 | } | |
3453 | else | |
3454 | store_waitstatus (ourstatus, status); | |
3455 | ||
01124a23 | 3456 | if (debug_linux_nat) |
b84876c2 PA |
3457 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3458 | ||
7feb7d06 | 3459 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3460 | |
4b60df3d | 3461 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3462 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3463 | && WSTOPSIG (status) == SIGSTOP) | |
3464 | { | |
3465 | /* A thread that has been requested to stop by GDB with | |
3466 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3467 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3468 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3469 | } |
3470 | ||
1e225492 JK |
3471 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3472 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3473 | lp->core = -1; | |
3474 | else | |
2e794194 | 3475 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3476 | |
aa01bd36 PA |
3477 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
3478 | return filter_exit_event (lp, ourstatus); | |
3479 | ||
f973ed9c | 3480 | return lp->ptid; |
d6b0e80f AC |
3481 | } |
3482 | ||
e3e9f5a2 PA |
3483 | /* Resume LWPs that are currently stopped without any pending status |
3484 | to report, but are resumed from the core's perspective. */ | |
3485 | ||
3486 | static int | |
3487 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3488 | { | |
9a3c8263 | 3489 | ptid_t *wait_ptid_p = (ptid_t *) data; |
e3e9f5a2 | 3490 | |
4dd63d48 PA |
3491 | if (!lp->stopped) |
3492 | { | |
3493 | if (debug_linux_nat) | |
3494 | fprintf_unfiltered (gdb_stdlog, | |
3495 | "RSRL: NOT resuming LWP %s, not stopped\n", | |
3496 | target_pid_to_str (lp->ptid)); | |
3497 | } | |
3498 | else if (!lp->resumed) | |
3499 | { | |
3500 | if (debug_linux_nat) | |
3501 | fprintf_unfiltered (gdb_stdlog, | |
3502 | "RSRL: NOT resuming LWP %s, not resumed\n", | |
3503 | target_pid_to_str (lp->ptid)); | |
3504 | } | |
3505 | else if (lwp_status_pending_p (lp)) | |
3506 | { | |
3507 | if (debug_linux_nat) | |
3508 | fprintf_unfiltered (gdb_stdlog, | |
3509 | "RSRL: NOT resuming LWP %s, has pending status\n", | |
3510 | target_pid_to_str (lp->ptid)); | |
3511 | } | |
3512 | else | |
e3e9f5a2 | 3513 | { |
336060f3 | 3514 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
ac7936df | 3515 | struct gdbarch *gdbarch = regcache->arch (); |
336060f3 | 3516 | |
23f238d3 | 3517 | TRY |
e3e9f5a2 | 3518 | { |
23f238d3 PA |
3519 | CORE_ADDR pc = regcache_read_pc (regcache); |
3520 | int leave_stopped = 0; | |
e3e9f5a2 | 3521 | |
23f238d3 PA |
3522 | /* Don't bother if there's a breakpoint at PC that we'd hit |
3523 | immediately, and we're not waiting for this LWP. */ | |
26a57c92 | 3524 | if (!lp->ptid.matches (*wait_ptid_p)) |
23f238d3 | 3525 | { |
a01bda52 | 3526 | if (breakpoint_inserted_here_p (regcache->aspace (), pc)) |
23f238d3 PA |
3527 | leave_stopped = 1; |
3528 | } | |
e3e9f5a2 | 3529 | |
23f238d3 PA |
3530 | if (!leave_stopped) |
3531 | { | |
3532 | if (debug_linux_nat) | |
3533 | fprintf_unfiltered (gdb_stdlog, | |
3534 | "RSRL: resuming stopped-resumed LWP %s at " | |
3535 | "%s: step=%d\n", | |
3536 | target_pid_to_str (lp->ptid), | |
3537 | paddress (gdbarch, pc), | |
3538 | lp->step); | |
3539 | ||
3540 | linux_resume_one_lwp_throw (lp, lp->step, GDB_SIGNAL_0); | |
3541 | } | |
3542 | } | |
3543 | CATCH (ex, RETURN_MASK_ERROR) | |
3544 | { | |
3545 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
3546 | throw_exception (ex); | |
3547 | } | |
3548 | END_CATCH | |
e3e9f5a2 PA |
3549 | } |
3550 | ||
3551 | return 0; | |
3552 | } | |
3553 | ||
f6ac5f3d PA |
3554 | ptid_t |
3555 | linux_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus, | |
3556 | int target_options) | |
7feb7d06 PA |
3557 | { |
3558 | ptid_t event_ptid; | |
3559 | ||
3560 | if (debug_linux_nat) | |
09826ec5 | 3561 | { |
09ce46f2 | 3562 | std::string options_string = target_options_to_string (target_options); |
09826ec5 PA |
3563 | fprintf_unfiltered (gdb_stdlog, |
3564 | "linux_nat_wait: [%s], [%s]\n", | |
3565 | target_pid_to_str (ptid), | |
09ce46f2 | 3566 | options_string.c_str ()); |
09826ec5 | 3567 | } |
7feb7d06 PA |
3568 | |
3569 | /* Flush the async file first. */ | |
d9d41e78 | 3570 | if (target_is_async_p ()) |
7feb7d06 PA |
3571 | async_file_flush (); |
3572 | ||
e3e9f5a2 PA |
3573 | /* Resume LWPs that are currently stopped without any pending status |
3574 | to report, but are resumed from the core's perspective. LWPs get | |
3575 | in this state if we find them stopping at a time we're not | |
3576 | interested in reporting the event (target_wait on a | |
3577 | specific_process, for example, see linux_nat_wait_1), and | |
3578 | meanwhile the event became uninteresting. Don't bother resuming | |
3579 | LWPs we're not going to wait for if they'd stop immediately. */ | |
fbea99ea | 3580 | if (target_is_non_stop_p ()) |
e3e9f5a2 PA |
3581 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); |
3582 | ||
f6ac5f3d | 3583 | event_ptid = linux_nat_wait_1 (ptid, ourstatus, target_options); |
7feb7d06 PA |
3584 | |
3585 | /* If we requested any event, and something came out, assume there | |
3586 | may be more. If we requested a specific lwp or process, also | |
3587 | assume there may be more. */ | |
d9d41e78 | 3588 | if (target_is_async_p () |
6953d224 PA |
3589 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3590 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
d7e15655 | 3591 | || ptid != minus_one_ptid)) |
7feb7d06 PA |
3592 | async_file_mark (); |
3593 | ||
7feb7d06 PA |
3594 | return event_ptid; |
3595 | } | |
3596 | ||
1d2736d4 PA |
3597 | /* Kill one LWP. */ |
3598 | ||
3599 | static void | |
3600 | kill_one_lwp (pid_t pid) | |
d6b0e80f | 3601 | { |
ed731959 JK |
3602 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3603 | ||
3604 | errno = 0; | |
1d2736d4 | 3605 | kill_lwp (pid, SIGKILL); |
ed731959 | 3606 | if (debug_linux_nat) |
57745c90 PA |
3607 | { |
3608 | int save_errno = errno; | |
3609 | ||
3610 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 | 3611 | "KC: kill (SIGKILL) %ld, 0, 0 (%s)\n", (long) pid, |
57745c90 PA |
3612 | save_errno ? safe_strerror (save_errno) : "OK"); |
3613 | } | |
ed731959 JK |
3614 | |
3615 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3616 | ||
d6b0e80f | 3617 | errno = 0; |
1d2736d4 | 3618 | ptrace (PTRACE_KILL, pid, 0, 0); |
d6b0e80f | 3619 | if (debug_linux_nat) |
57745c90 PA |
3620 | { |
3621 | int save_errno = errno; | |
3622 | ||
3623 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 | 3624 | "KC: PTRACE_KILL %ld, 0, 0 (%s)\n", (long) pid, |
57745c90 PA |
3625 | save_errno ? safe_strerror (save_errno) : "OK"); |
3626 | } | |
d6b0e80f AC |
3627 | } |
3628 | ||
1d2736d4 PA |
3629 | /* Wait for an LWP to die. */ |
3630 | ||
3631 | static void | |
3632 | kill_wait_one_lwp (pid_t pid) | |
d6b0e80f | 3633 | { |
1d2736d4 | 3634 | pid_t res; |
d6b0e80f AC |
3635 | |
3636 | /* We must make sure that there are no pending events (delayed | |
3637 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3638 | program doesn't interfere with any following debugging session. */ | |
3639 | ||
d6b0e80f AC |
3640 | do |
3641 | { | |
1d2736d4 PA |
3642 | res = my_waitpid (pid, NULL, __WALL); |
3643 | if (res != (pid_t) -1) | |
d6b0e80f | 3644 | { |
e85a822c DJ |
3645 | if (debug_linux_nat) |
3646 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 PA |
3647 | "KWC: wait %ld received unknown.\n", |
3648 | (long) pid); | |
4a6ed09b PA |
3649 | /* The Linux kernel sometimes fails to kill a thread |
3650 | completely after PTRACE_KILL; that goes from the stop | |
3651 | point in do_fork out to the one in get_signal_to_deliver | |
3652 | and waits again. So kill it again. */ | |
1d2736d4 | 3653 | kill_one_lwp (pid); |
d6b0e80f AC |
3654 | } |
3655 | } | |
1d2736d4 PA |
3656 | while (res == pid); |
3657 | ||
3658 | gdb_assert (res == -1 && errno == ECHILD); | |
3659 | } | |
3660 | ||
3661 | /* Callback for iterate_over_lwps. */ | |
d6b0e80f | 3662 | |
1d2736d4 PA |
3663 | static int |
3664 | kill_callback (struct lwp_info *lp, void *data) | |
3665 | { | |
e38504b3 | 3666 | kill_one_lwp (lp->ptid.lwp ()); |
d6b0e80f AC |
3667 | return 0; |
3668 | } | |
3669 | ||
1d2736d4 PA |
3670 | /* Callback for iterate_over_lwps. */ |
3671 | ||
3672 | static int | |
3673 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3674 | { | |
e38504b3 | 3675 | kill_wait_one_lwp (lp->ptid.lwp ()); |
1d2736d4 PA |
3676 | return 0; |
3677 | } | |
3678 | ||
3679 | /* Kill the fork children of any threads of inferior INF that are | |
3680 | stopped at a fork event. */ | |
3681 | ||
3682 | static void | |
3683 | kill_unfollowed_fork_children (struct inferior *inf) | |
3684 | { | |
08036331 PA |
3685 | for (thread_info *thread : inf->non_exited_threads ()) |
3686 | { | |
3687 | struct target_waitstatus *ws = &thread->pending_follow; | |
1d2736d4 | 3688 | |
08036331 PA |
3689 | if (ws->kind == TARGET_WAITKIND_FORKED |
3690 | || ws->kind == TARGET_WAITKIND_VFORKED) | |
3691 | { | |
3692 | ptid_t child_ptid = ws->value.related_pid; | |
3693 | int child_pid = child_ptid.pid (); | |
3694 | int child_lwp = child_ptid.lwp (); | |
3695 | ||
3696 | kill_one_lwp (child_lwp); | |
3697 | kill_wait_one_lwp (child_lwp); | |
3698 | ||
3699 | /* Let the arch-specific native code know this process is | |
3700 | gone. */ | |
3701 | linux_target->low_forget_process (child_pid); | |
3702 | } | |
3703 | } | |
1d2736d4 PA |
3704 | } |
3705 | ||
f6ac5f3d PA |
3706 | void |
3707 | linux_nat_target::kill () | |
d6b0e80f | 3708 | { |
f973ed9c DJ |
3709 | /* If we're stopped while forking and we haven't followed yet, |
3710 | kill the other task. We need to do this first because the | |
3711 | parent will be sleeping if this is a vfork. */ | |
1d2736d4 | 3712 | kill_unfollowed_fork_children (current_inferior ()); |
f973ed9c DJ |
3713 | |
3714 | if (forks_exist_p ()) | |
7feb7d06 | 3715 | linux_fork_killall (); |
f973ed9c DJ |
3716 | else |
3717 | { | |
e99b03dc | 3718 | ptid_t ptid = ptid_t (inferior_ptid.pid ()); |
e0881a8e | 3719 | |
4c28f408 PA |
3720 | /* Stop all threads before killing them, since ptrace requires |
3721 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3722 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3723 | /* ... and wait until all of them have reported back that |
3724 | they're no longer running. */ | |
d90e17a7 | 3725 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3726 | |
f973ed9c | 3727 | /* Kill all LWP's ... */ |
d90e17a7 | 3728 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3729 | |
3730 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3731 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3732 | } |
3733 | ||
bc1e6c81 | 3734 | target_mourn_inferior (inferior_ptid); |
d6b0e80f AC |
3735 | } |
3736 | ||
f6ac5f3d PA |
3737 | void |
3738 | linux_nat_target::mourn_inferior () | |
d6b0e80f | 3739 | { |
e99b03dc | 3740 | int pid = inferior_ptid.pid (); |
26cb8b7c PA |
3741 | |
3742 | purge_lwp_list (pid); | |
d6b0e80f | 3743 | |
f973ed9c | 3744 | if (! forks_exist_p ()) |
d90e17a7 | 3745 | /* Normal case, no other forks available. */ |
f6ac5f3d | 3746 | inf_ptrace_target::mourn_inferior (); |
f973ed9c DJ |
3747 | else |
3748 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3749 | there are other viable forks to debug. Delete the exiting | |
3750 | one and context-switch to the first available. */ | |
3751 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3752 | |
3753 | /* Let the arch-specific native code know this process is gone. */ | |
135340af | 3754 | linux_target->low_forget_process (pid); |
d6b0e80f AC |
3755 | } |
3756 | ||
5b009018 PA |
3757 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3758 | layout of the inferiors' architecture. */ | |
3759 | ||
3760 | static void | |
a5362b9a | 3761 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 | 3762 | { |
135340af PA |
3763 | /* If the low target didn't do anything, then just do a straight |
3764 | memcpy. */ | |
3765 | if (!linux_target->low_siginfo_fixup (siginfo, inf_siginfo, direction)) | |
5b009018 PA |
3766 | { |
3767 | if (direction == 1) | |
a5362b9a | 3768 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3769 | else |
a5362b9a | 3770 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3771 | } |
3772 | } | |
3773 | ||
9b409511 | 3774 | static enum target_xfer_status |
f6ac5f3d | 3775 | linux_xfer_siginfo (enum target_object object, |
4aa995e1 | 3776 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
3777 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3778 | ULONGEST *xfered_len) | |
4aa995e1 | 3779 | { |
4aa995e1 | 3780 | int pid; |
a5362b9a TS |
3781 | siginfo_t siginfo; |
3782 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3783 | |
3784 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3785 | gdb_assert (readbuf || writebuf); | |
3786 | ||
e38504b3 | 3787 | pid = inferior_ptid.lwp (); |
4aa995e1 | 3788 | if (pid == 0) |
e99b03dc | 3789 | pid = inferior_ptid.pid (); |
4aa995e1 PA |
3790 | |
3791 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3792 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3793 | |
3794 | errno = 0; | |
3795 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3796 | if (errno != 0) | |
2ed4b548 | 3797 | return TARGET_XFER_E_IO; |
4aa995e1 | 3798 | |
5b009018 PA |
3799 | /* When GDB is built as a 64-bit application, ptrace writes into |
3800 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3801 | inferior with a 64-bit GDB should look the same as debugging it | |
3802 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3803 | the converted layout, so any read/write will have to be done | |
3804 | post-conversion. */ | |
3805 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3806 | ||
4aa995e1 PA |
3807 | if (offset + len > sizeof (siginfo)) |
3808 | len = sizeof (siginfo) - offset; | |
3809 | ||
3810 | if (readbuf != NULL) | |
5b009018 | 3811 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3812 | else |
3813 | { | |
5b009018 PA |
3814 | memcpy (inf_siginfo + offset, writebuf, len); |
3815 | ||
3816 | /* Convert back to ptrace layout before flushing it out. */ | |
3817 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3818 | ||
4aa995e1 PA |
3819 | errno = 0; |
3820 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3821 | if (errno != 0) | |
2ed4b548 | 3822 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3823 | } |
3824 | ||
9b409511 YQ |
3825 | *xfered_len = len; |
3826 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3827 | } |
3828 | ||
9b409511 | 3829 | static enum target_xfer_status |
f6ac5f3d PA |
3830 | linux_nat_xfer_osdata (enum target_object object, |
3831 | const char *annex, gdb_byte *readbuf, | |
3832 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, | |
3833 | ULONGEST *xfered_len); | |
3834 | ||
3835 | static enum target_xfer_status | |
3836 | linux_proc_xfer_spu (enum target_object object, | |
3837 | const char *annex, gdb_byte *readbuf, | |
3838 | const gdb_byte *writebuf, | |
3839 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len); | |
3840 | ||
3841 | static enum target_xfer_status | |
3842 | linux_proc_xfer_partial (enum target_object object, | |
3843 | const char *annex, gdb_byte *readbuf, | |
3844 | const gdb_byte *writebuf, | |
3845 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len); | |
3846 | ||
3847 | enum target_xfer_status | |
3848 | linux_nat_target::xfer_partial (enum target_object object, | |
3849 | const char *annex, gdb_byte *readbuf, | |
3850 | const gdb_byte *writebuf, | |
3851 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) | |
d6b0e80f | 3852 | { |
9b409511 | 3853 | enum target_xfer_status xfer; |
d6b0e80f | 3854 | |
4aa995e1 | 3855 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
f6ac5f3d | 3856 | return linux_xfer_siginfo (object, annex, readbuf, writebuf, |
9b409511 | 3857 | offset, len, xfered_len); |
4aa995e1 | 3858 | |
c35b1492 PA |
3859 | /* The target is connected but no live inferior is selected. Pass |
3860 | this request down to a lower stratum (e.g., the executable | |
3861 | file). */ | |
d7e15655 | 3862 | if (object == TARGET_OBJECT_MEMORY && inferior_ptid == null_ptid) |
9b409511 | 3863 | return TARGET_XFER_EOF; |
c35b1492 | 3864 | |
f6ac5f3d PA |
3865 | if (object == TARGET_OBJECT_AUXV) |
3866 | return memory_xfer_auxv (this, object, annex, readbuf, writebuf, | |
3867 | offset, len, xfered_len); | |
3868 | ||
3869 | if (object == TARGET_OBJECT_OSDATA) | |
3870 | return linux_nat_xfer_osdata (object, annex, readbuf, writebuf, | |
3871 | offset, len, xfered_len); | |
d6b0e80f | 3872 | |
f6ac5f3d PA |
3873 | if (object == TARGET_OBJECT_SPU) |
3874 | return linux_proc_xfer_spu (object, annex, readbuf, writebuf, | |
3875 | offset, len, xfered_len); | |
3876 | ||
3877 | /* GDB calculates all addresses in the largest possible address | |
3878 | width. | |
3879 | The address width must be masked before its final use - either by | |
3880 | linux_proc_xfer_partial or inf_ptrace_target::xfer_partial. | |
3881 | ||
3882 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
3883 | ||
3884 | if (object == TARGET_OBJECT_MEMORY) | |
3885 | { | |
3886 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); | |
3887 | ||
3888 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
3889 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
3890 | } | |
3891 | ||
3892 | xfer = linux_proc_xfer_partial (object, annex, readbuf, writebuf, | |
3893 | offset, len, xfered_len); | |
3894 | if (xfer != TARGET_XFER_EOF) | |
3895 | return xfer; | |
3896 | ||
3897 | return inf_ptrace_target::xfer_partial (object, annex, readbuf, writebuf, | |
3898 | offset, len, xfered_len); | |
d6b0e80f AC |
3899 | } |
3900 | ||
57810aa7 | 3901 | bool |
f6ac5f3d | 3902 | linux_nat_target::thread_alive (ptid_t ptid) |
28439f5e | 3903 | { |
4a6ed09b PA |
3904 | /* As long as a PTID is in lwp list, consider it alive. */ |
3905 | return find_lwp_pid (ptid) != NULL; | |
28439f5e PA |
3906 | } |
3907 | ||
8a06aea7 PA |
3908 | /* Implement the to_update_thread_list target method for this |
3909 | target. */ | |
3910 | ||
f6ac5f3d PA |
3911 | void |
3912 | linux_nat_target::update_thread_list () | |
8a06aea7 | 3913 | { |
a6904d5a PA |
3914 | struct lwp_info *lwp; |
3915 | ||
4a6ed09b PA |
3916 | /* We add/delete threads from the list as clone/exit events are |
3917 | processed, so just try deleting exited threads still in the | |
3918 | thread list. */ | |
3919 | delete_exited_threads (); | |
a6904d5a PA |
3920 | |
3921 | /* Update the processor core that each lwp/thread was last seen | |
3922 | running on. */ | |
3923 | ALL_LWPS (lwp) | |
1ad3de98 PA |
3924 | { |
3925 | /* Avoid accessing /proc if the thread hasn't run since we last | |
3926 | time we fetched the thread's core. Accessing /proc becomes | |
3927 | noticeably expensive when we have thousands of LWPs. */ | |
3928 | if (lwp->core == -1) | |
3929 | lwp->core = linux_common_core_of_thread (lwp->ptid); | |
3930 | } | |
8a06aea7 PA |
3931 | } |
3932 | ||
f6ac5f3d PA |
3933 | const char * |
3934 | linux_nat_target::pid_to_str (ptid_t ptid) | |
d6b0e80f AC |
3935 | { |
3936 | static char buf[64]; | |
3937 | ||
15a9e13e | 3938 | if (ptid.lwp_p () |
e38504b3 | 3939 | && (ptid.pid () != ptid.lwp () |
e99b03dc | 3940 | || num_lwps (ptid.pid ()) > 1)) |
d6b0e80f | 3941 | { |
e38504b3 | 3942 | snprintf (buf, sizeof (buf), "LWP %ld", ptid.lwp ()); |
d6b0e80f AC |
3943 | return buf; |
3944 | } | |
3945 | ||
3946 | return normal_pid_to_str (ptid); | |
3947 | } | |
3948 | ||
f6ac5f3d PA |
3949 | const char * |
3950 | linux_nat_target::thread_name (struct thread_info *thr) | |
4694da01 | 3951 | { |
79efa585 | 3952 | return linux_proc_tid_get_name (thr->ptid); |
4694da01 TT |
3953 | } |
3954 | ||
dba24537 AC |
3955 | /* Accepts an integer PID; Returns a string representing a file that |
3956 | can be opened to get the symbols for the child process. */ | |
3957 | ||
f6ac5f3d PA |
3958 | char * |
3959 | linux_nat_target::pid_to_exec_file (int pid) | |
dba24537 | 3960 | { |
e0d86d2c | 3961 | return linux_proc_pid_to_exec_file (pid); |
dba24537 AC |
3962 | } |
3963 | ||
a379284a AA |
3964 | /* Implement the to_xfer_partial target method using /proc/<pid>/mem. |
3965 | Because we can use a single read/write call, this can be much more | |
3966 | efficient than banging away at PTRACE_PEEKTEXT. */ | |
10d6c8cd | 3967 | |
9b409511 | 3968 | static enum target_xfer_status |
f6ac5f3d | 3969 | linux_proc_xfer_partial (enum target_object object, |
10d6c8cd DJ |
3970 | const char *annex, gdb_byte *readbuf, |
3971 | const gdb_byte *writebuf, | |
9b409511 | 3972 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 3973 | { |
10d6c8cd DJ |
3974 | LONGEST ret; |
3975 | int fd; | |
dba24537 AC |
3976 | char filename[64]; |
3977 | ||
a379284a | 3978 | if (object != TARGET_OBJECT_MEMORY) |
f486487f | 3979 | return TARGET_XFER_EOF; |
dba24537 AC |
3980 | |
3981 | /* Don't bother for one word. */ | |
3982 | if (len < 3 * sizeof (long)) | |
9b409511 | 3983 | return TARGET_XFER_EOF; |
dba24537 AC |
3984 | |
3985 | /* We could keep this file open and cache it - possibly one per | |
3986 | thread. That requires some juggling, but is even faster. */ | |
b67aeab0 | 3987 | xsnprintf (filename, sizeof filename, "/proc/%ld/mem", |
e38504b3 | 3988 | inferior_ptid.lwp ()); |
a379284a AA |
3989 | fd = gdb_open_cloexec (filename, ((readbuf ? O_RDONLY : O_WRONLY) |
3990 | | O_LARGEFILE), 0); | |
dba24537 | 3991 | if (fd == -1) |
9b409511 | 3992 | return TARGET_XFER_EOF; |
dba24537 | 3993 | |
a379284a AA |
3994 | /* Use pread64/pwrite64 if available, since they save a syscall and can |
3995 | handle 64-bit offsets even on 32-bit platforms (for instance, SPARC | |
3996 | debugging a SPARC64 application). */ | |
dba24537 | 3997 | #ifdef HAVE_PREAD64 |
a379284a AA |
3998 | ret = (readbuf ? pread64 (fd, readbuf, len, offset) |
3999 | : pwrite64 (fd, writebuf, len, offset)); | |
dba24537 | 4000 | #else |
a379284a AA |
4001 | ret = lseek (fd, offset, SEEK_SET); |
4002 | if (ret != -1) | |
4003 | ret = (readbuf ? read (fd, readbuf, len) | |
4004 | : write (fd, writebuf, len)); | |
dba24537 | 4005 | #endif |
dba24537 AC |
4006 | |
4007 | close (fd); | |
9b409511 | 4008 | |
a379284a | 4009 | if (ret == -1 || ret == 0) |
9b409511 YQ |
4010 | return TARGET_XFER_EOF; |
4011 | else | |
4012 | { | |
4013 | *xfered_len = ret; | |
4014 | return TARGET_XFER_OK; | |
4015 | } | |
dba24537 AC |
4016 | } |
4017 | ||
efcbbd14 UW |
4018 | |
4019 | /* Enumerate spufs IDs for process PID. */ | |
4020 | static LONGEST | |
b55e14c7 | 4021 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4022 | { |
f5656ead | 4023 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4024 | LONGEST pos = 0; |
4025 | LONGEST written = 0; | |
4026 | char path[128]; | |
4027 | DIR *dir; | |
4028 | struct dirent *entry; | |
4029 | ||
4030 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4031 | dir = opendir (path); | |
4032 | if (!dir) | |
4033 | return -1; | |
4034 | ||
4035 | rewinddir (dir); | |
4036 | while ((entry = readdir (dir)) != NULL) | |
4037 | { | |
4038 | struct stat st; | |
4039 | struct statfs stfs; | |
4040 | int fd; | |
4041 | ||
4042 | fd = atoi (entry->d_name); | |
4043 | if (!fd) | |
4044 | continue; | |
4045 | ||
4046 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4047 | if (stat (path, &st) != 0) | |
4048 | continue; | |
4049 | if (!S_ISDIR (st.st_mode)) | |
4050 | continue; | |
4051 | ||
4052 | if (statfs (path, &stfs) != 0) | |
4053 | continue; | |
4054 | if (stfs.f_type != SPUFS_MAGIC) | |
4055 | continue; | |
4056 | ||
4057 | if (pos >= offset && pos + 4 <= offset + len) | |
4058 | { | |
4059 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4060 | written += 4; | |
4061 | } | |
4062 | pos += 4; | |
4063 | } | |
4064 | ||
4065 | closedir (dir); | |
4066 | return written; | |
4067 | } | |
4068 | ||
4069 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4070 | object type, using the /proc file system. */ | |
9b409511 YQ |
4071 | |
4072 | static enum target_xfer_status | |
f6ac5f3d | 4073 | linux_proc_xfer_spu (enum target_object object, |
efcbbd14 UW |
4074 | const char *annex, gdb_byte *readbuf, |
4075 | const gdb_byte *writebuf, | |
9b409511 | 4076 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4077 | { |
4078 | char buf[128]; | |
4079 | int fd = 0; | |
4080 | int ret = -1; | |
e38504b3 | 4081 | int pid = inferior_ptid.lwp (); |
efcbbd14 UW |
4082 | |
4083 | if (!annex) | |
4084 | { | |
4085 | if (!readbuf) | |
2ed4b548 | 4086 | return TARGET_XFER_E_IO; |
efcbbd14 | 4087 | else |
9b409511 YQ |
4088 | { |
4089 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4090 | ||
4091 | if (l < 0) | |
4092 | return TARGET_XFER_E_IO; | |
4093 | else if (l == 0) | |
4094 | return TARGET_XFER_EOF; | |
4095 | else | |
4096 | { | |
4097 | *xfered_len = (ULONGEST) l; | |
4098 | return TARGET_XFER_OK; | |
4099 | } | |
4100 | } | |
efcbbd14 UW |
4101 | } |
4102 | ||
4103 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4104 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4105 | if (fd <= 0) |
2ed4b548 | 4106 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4107 | |
4108 | if (offset != 0 | |
4109 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4110 | { | |
4111 | close (fd); | |
9b409511 | 4112 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4113 | } |
4114 | ||
4115 | if (writebuf) | |
4116 | ret = write (fd, writebuf, (size_t) len); | |
4117 | else if (readbuf) | |
4118 | ret = read (fd, readbuf, (size_t) len); | |
4119 | ||
4120 | close (fd); | |
9b409511 YQ |
4121 | |
4122 | if (ret < 0) | |
4123 | return TARGET_XFER_E_IO; | |
4124 | else if (ret == 0) | |
4125 | return TARGET_XFER_EOF; | |
4126 | else | |
4127 | { | |
4128 | *xfered_len = (ULONGEST) ret; | |
4129 | return TARGET_XFER_OK; | |
4130 | } | |
efcbbd14 UW |
4131 | } |
4132 | ||
4133 | ||
dba24537 AC |
4134 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4135 | ||
4136 | static void | |
4137 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4138 | { | |
4139 | int len = strlen (line) - 1; | |
4140 | const char *p; | |
4141 | int signum; | |
4142 | ||
4143 | if (line[len] != '\n') | |
8a3fe4f8 | 4144 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4145 | |
4146 | p = line; | |
4147 | signum = len * 4; | |
4148 | while (len-- > 0) | |
4149 | { | |
4150 | int digit; | |
4151 | ||
4152 | if (*p >= '0' && *p <= '9') | |
4153 | digit = *p - '0'; | |
4154 | else if (*p >= 'a' && *p <= 'f') | |
4155 | digit = *p - 'a' + 10; | |
4156 | else | |
8a3fe4f8 | 4157 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4158 | |
4159 | signum -= 4; | |
4160 | ||
4161 | if (digit & 1) | |
4162 | sigaddset (sigs, signum + 1); | |
4163 | if (digit & 2) | |
4164 | sigaddset (sigs, signum + 2); | |
4165 | if (digit & 4) | |
4166 | sigaddset (sigs, signum + 3); | |
4167 | if (digit & 8) | |
4168 | sigaddset (sigs, signum + 4); | |
4169 | ||
4170 | p++; | |
4171 | } | |
4172 | } | |
4173 | ||
4174 | /* Find process PID's pending signals from /proc/pid/status and set | |
4175 | SIGS to match. */ | |
4176 | ||
4177 | void | |
3e43a32a MS |
4178 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4179 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 | 4180 | { |
d8d2a3ee | 4181 | char buffer[PATH_MAX], fname[PATH_MAX]; |
dba24537 AC |
4182 | |
4183 | sigemptyset (pending); | |
4184 | sigemptyset (blocked); | |
4185 | sigemptyset (ignored); | |
cde33bf1 | 4186 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
d419f42d | 4187 | gdb_file_up procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4188 | if (procfile == NULL) |
8a3fe4f8 | 4189 | error (_("Could not open %s"), fname); |
dba24537 | 4190 | |
d419f42d | 4191 | while (fgets (buffer, PATH_MAX, procfile.get ()) != NULL) |
dba24537 AC |
4192 | { |
4193 | /* Normal queued signals are on the SigPnd line in the status | |
4194 | file. However, 2.6 kernels also have a "shared" pending | |
4195 | queue for delivering signals to a thread group, so check for | |
4196 | a ShdPnd line also. | |
4197 | ||
4198 | Unfortunately some Red Hat kernels include the shared pending | |
4199 | queue but not the ShdPnd status field. */ | |
4200 | ||
61012eef | 4201 | if (startswith (buffer, "SigPnd:\t")) |
dba24537 | 4202 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4203 | else if (startswith (buffer, "ShdPnd:\t")) |
dba24537 | 4204 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4205 | else if (startswith (buffer, "SigBlk:\t")) |
dba24537 | 4206 | add_line_to_sigset (buffer + 8, blocked); |
61012eef | 4207 | else if (startswith (buffer, "SigIgn:\t")) |
dba24537 AC |
4208 | add_line_to_sigset (buffer + 8, ignored); |
4209 | } | |
dba24537 AC |
4210 | } |
4211 | ||
9b409511 | 4212 | static enum target_xfer_status |
f6ac5f3d | 4213 | linux_nat_xfer_osdata (enum target_object object, |
e0881a8e | 4214 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4215 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4216 | ULONGEST *xfered_len) | |
07e059b5 | 4217 | { |
07e059b5 VP |
4218 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4219 | ||
9b409511 YQ |
4220 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4221 | if (*xfered_len == 0) | |
4222 | return TARGET_XFER_EOF; | |
4223 | else | |
4224 | return TARGET_XFER_OK; | |
07e059b5 VP |
4225 | } |
4226 | ||
f6ac5f3d PA |
4227 | std::vector<static_tracepoint_marker> |
4228 | linux_nat_target::static_tracepoint_markers_by_strid (const char *strid) | |
5808517f YQ |
4229 | { |
4230 | char s[IPA_CMD_BUF_SIZE]; | |
e99b03dc | 4231 | int pid = inferior_ptid.pid (); |
5d9310c4 | 4232 | std::vector<static_tracepoint_marker> markers; |
256642e8 | 4233 | const char *p = s; |
fd79271b | 4234 | ptid_t ptid = ptid_t (pid, 0, 0); |
5d9310c4 | 4235 | static_tracepoint_marker marker; |
5808517f YQ |
4236 | |
4237 | /* Pause all */ | |
4238 | target_stop (ptid); | |
4239 | ||
4240 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4241 | s[sizeof ("qTfSTM")] = 0; | |
4242 | ||
42476b70 | 4243 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f | 4244 | |
1db93f14 TT |
4245 | /* Unpause all. */ |
4246 | SCOPE_EXIT { target_continue_no_signal (ptid); }; | |
5808517f YQ |
4247 | |
4248 | while (*p++ == 'm') | |
4249 | { | |
5808517f YQ |
4250 | do |
4251 | { | |
5d9310c4 | 4252 | parse_static_tracepoint_marker_definition (p, &p, &marker); |
5808517f | 4253 | |
5d9310c4 SM |
4254 | if (strid == NULL || marker.str_id == strid) |
4255 | markers.push_back (std::move (marker)); | |
5808517f YQ |
4256 | } |
4257 | while (*p++ == ','); /* comma-separated list */ | |
4258 | ||
4259 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4260 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4261 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4262 | p = s; |
4263 | } | |
4264 | ||
5808517f YQ |
4265 | return markers; |
4266 | } | |
4267 | ||
b84876c2 PA |
4268 | /* target_is_async_p implementation. */ |
4269 | ||
57810aa7 | 4270 | bool |
f6ac5f3d | 4271 | linux_nat_target::is_async_p () |
b84876c2 | 4272 | { |
198297aa | 4273 | return linux_is_async_p (); |
b84876c2 PA |
4274 | } |
4275 | ||
4276 | /* target_can_async_p implementation. */ | |
4277 | ||
57810aa7 | 4278 | bool |
f6ac5f3d | 4279 | linux_nat_target::can_async_p () |
b84876c2 | 4280 | { |
fde1b17d SM |
4281 | /* We're always async, unless the user explicitly prevented it with the |
4282 | "maint set target-async" command. */ | |
3dd5b83d | 4283 | return target_async_permitted; |
b84876c2 PA |
4284 | } |
4285 | ||
57810aa7 | 4286 | bool |
f6ac5f3d | 4287 | linux_nat_target::supports_non_stop () |
9908b566 VP |
4288 | { |
4289 | return 1; | |
4290 | } | |
4291 | ||
fbea99ea PA |
4292 | /* to_always_non_stop_p implementation. */ |
4293 | ||
57810aa7 | 4294 | bool |
f6ac5f3d | 4295 | linux_nat_target::always_non_stop_p () |
fbea99ea | 4296 | { |
f12899e9 | 4297 | return 1; |
fbea99ea PA |
4298 | } |
4299 | ||
d90e17a7 PA |
4300 | /* True if we want to support multi-process. To be removed when GDB |
4301 | supports multi-exec. */ | |
4302 | ||
2277426b | 4303 | int linux_multi_process = 1; |
d90e17a7 | 4304 | |
57810aa7 | 4305 | bool |
f6ac5f3d | 4306 | linux_nat_target::supports_multi_process () |
d90e17a7 PA |
4307 | { |
4308 | return linux_multi_process; | |
4309 | } | |
4310 | ||
57810aa7 | 4311 | bool |
f6ac5f3d | 4312 | linux_nat_target::supports_disable_randomization () |
03583c20 UW |
4313 | { |
4314 | #ifdef HAVE_PERSONALITY | |
4315 | return 1; | |
4316 | #else | |
4317 | return 0; | |
4318 | #endif | |
4319 | } | |
4320 | ||
7feb7d06 PA |
4321 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4322 | so we notice when any child changes state, and notify the | |
4323 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4324 | above to wait for the arrival of a SIGCHLD. */ | |
4325 | ||
b84876c2 | 4326 | static void |
7feb7d06 | 4327 | sigchld_handler (int signo) |
b84876c2 | 4328 | { |
7feb7d06 PA |
4329 | int old_errno = errno; |
4330 | ||
01124a23 DE |
4331 | if (debug_linux_nat) |
4332 | ui_file_write_async_safe (gdb_stdlog, | |
4333 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4334 | |
4335 | if (signo == SIGCHLD | |
4336 | && linux_nat_event_pipe[0] != -1) | |
4337 | async_file_mark (); /* Let the event loop know that there are | |
4338 | events to handle. */ | |
4339 | ||
4340 | errno = old_errno; | |
4341 | } | |
4342 | ||
4343 | /* Callback registered with the target events file descriptor. */ | |
4344 | ||
4345 | static void | |
4346 | handle_target_event (int error, gdb_client_data client_data) | |
4347 | { | |
6a3753b3 | 4348 | inferior_event_handler (INF_REG_EVENT, NULL); |
7feb7d06 PA |
4349 | } |
4350 | ||
4351 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4352 | ||
4353 | static int | |
4354 | linux_async_pipe (int enable) | |
4355 | { | |
198297aa | 4356 | int previous = linux_is_async_p (); |
7feb7d06 PA |
4357 | |
4358 | if (previous != enable) | |
4359 | { | |
4360 | sigset_t prev_mask; | |
4361 | ||
12696c10 PA |
4362 | /* Block child signals while we create/destroy the pipe, as |
4363 | their handler writes to it. */ | |
7feb7d06 PA |
4364 | block_child_signals (&prev_mask); |
4365 | ||
4366 | if (enable) | |
4367 | { | |
614c279d | 4368 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4369 | internal_error (__FILE__, __LINE__, |
4370 | "creating event pipe failed."); | |
4371 | ||
4372 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4373 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4374 | } | |
4375 | else | |
4376 | { | |
4377 | close (linux_nat_event_pipe[0]); | |
4378 | close (linux_nat_event_pipe[1]); | |
4379 | linux_nat_event_pipe[0] = -1; | |
4380 | linux_nat_event_pipe[1] = -1; | |
4381 | } | |
4382 | ||
4383 | restore_child_signals_mask (&prev_mask); | |
4384 | } | |
4385 | ||
4386 | return previous; | |
b84876c2 PA |
4387 | } |
4388 | ||
4389 | /* target_async implementation. */ | |
4390 | ||
f6ac5f3d PA |
4391 | void |
4392 | linux_nat_target::async (int enable) | |
b84876c2 | 4393 | { |
6a3753b3 | 4394 | if (enable) |
b84876c2 | 4395 | { |
7feb7d06 PA |
4396 | if (!linux_async_pipe (1)) |
4397 | { | |
4398 | add_file_handler (linux_nat_event_pipe[0], | |
4399 | handle_target_event, NULL); | |
4400 | /* There may be pending events to handle. Tell the event loop | |
4401 | to poll them. */ | |
4402 | async_file_mark (); | |
4403 | } | |
b84876c2 PA |
4404 | } |
4405 | else | |
4406 | { | |
b84876c2 | 4407 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4408 | linux_async_pipe (0); |
b84876c2 PA |
4409 | } |
4410 | return; | |
4411 | } | |
4412 | ||
a493e3e2 | 4413 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4414 | event came out. */ |
4415 | ||
4c28f408 | 4416 | static int |
252fbfc8 | 4417 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4418 | { |
d90e17a7 | 4419 | if (!lwp->stopped) |
252fbfc8 | 4420 | { |
d90e17a7 PA |
4421 | if (debug_linux_nat) |
4422 | fprintf_unfiltered (gdb_stdlog, | |
4423 | "LNSL: running -> suspending %s\n", | |
4424 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4425 | |
252fbfc8 | 4426 | |
25289eb2 PA |
4427 | if (lwp->last_resume_kind == resume_stop) |
4428 | { | |
4429 | if (debug_linux_nat) | |
4430 | fprintf_unfiltered (gdb_stdlog, | |
4431 | "linux-nat: already stopping LWP %ld at " | |
4432 | "GDB's request\n", | |
e38504b3 | 4433 | lwp->ptid.lwp ()); |
25289eb2 PA |
4434 | return 0; |
4435 | } | |
252fbfc8 | 4436 | |
25289eb2 PA |
4437 | stop_callback (lwp, NULL); |
4438 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4439 | } |
4440 | else | |
4441 | { | |
4442 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4443 | |
d90e17a7 PA |
4444 | if (debug_linux_nat) |
4445 | { | |
e09875d4 | 4446 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4447 | fprintf_unfiltered (gdb_stdlog, |
4448 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4449 | target_pid_to_str (lwp->ptid)); |
4450 | else | |
3e43a32a MS |
4451 | fprintf_unfiltered (gdb_stdlog, |
4452 | "LNSL: already stopped/no " | |
4453 | "stop_requested yet %s\n", | |
d90e17a7 | 4454 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4455 | } |
4456 | } | |
4c28f408 PA |
4457 | return 0; |
4458 | } | |
4459 | ||
f6ac5f3d PA |
4460 | void |
4461 | linux_nat_target::stop (ptid_t ptid) | |
4c28f408 | 4462 | { |
bfedc46a PA |
4463 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4464 | } | |
4465 | ||
f6ac5f3d PA |
4466 | void |
4467 | linux_nat_target::close () | |
d90e17a7 PA |
4468 | { |
4469 | /* Unregister from the event loop. */ | |
f6ac5f3d PA |
4470 | if (is_async_p ()) |
4471 | async (0); | |
d90e17a7 | 4472 | |
f6ac5f3d | 4473 | inf_ptrace_target::close (); |
d90e17a7 PA |
4474 | } |
4475 | ||
c0694254 PA |
4476 | /* When requests are passed down from the linux-nat layer to the |
4477 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4478 | used. The address space pointer is stored in the inferior object, | |
4479 | but the common code that is passed such ptid can't tell whether | |
4480 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4481 | look up the "main" process id from the lwp here. */ | |
4482 | ||
f6ac5f3d PA |
4483 | struct address_space * |
4484 | linux_nat_target::thread_address_space (ptid_t ptid) | |
c0694254 PA |
4485 | { |
4486 | struct lwp_info *lwp; | |
4487 | struct inferior *inf; | |
4488 | int pid; | |
4489 | ||
e38504b3 | 4490 | if (ptid.lwp () == 0) |
c0694254 PA |
4491 | { |
4492 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4493 | tgid. */ | |
4494 | lwp = find_lwp_pid (ptid); | |
e99b03dc | 4495 | pid = lwp->ptid.pid (); |
c0694254 PA |
4496 | } |
4497 | else | |
4498 | { | |
4499 | /* A (pid,lwpid,0) ptid. */ | |
e99b03dc | 4500 | pid = ptid.pid (); |
c0694254 PA |
4501 | } |
4502 | ||
4503 | inf = find_inferior_pid (pid); | |
4504 | gdb_assert (inf != NULL); | |
4505 | return inf->aspace; | |
4506 | } | |
4507 | ||
dc146f7c VP |
4508 | /* Return the cached value of the processor core for thread PTID. */ |
4509 | ||
f6ac5f3d PA |
4510 | int |
4511 | linux_nat_target::core_of_thread (ptid_t ptid) | |
dc146f7c VP |
4512 | { |
4513 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4514 | |
dc146f7c VP |
4515 | if (info) |
4516 | return info->core; | |
4517 | return -1; | |
4518 | } | |
4519 | ||
7a6a1731 GB |
4520 | /* Implementation of to_filesystem_is_local. */ |
4521 | ||
57810aa7 | 4522 | bool |
f6ac5f3d | 4523 | linux_nat_target::filesystem_is_local () |
7a6a1731 GB |
4524 | { |
4525 | struct inferior *inf = current_inferior (); | |
4526 | ||
4527 | if (inf->fake_pid_p || inf->pid == 0) | |
57810aa7 | 4528 | return true; |
7a6a1731 GB |
4529 | |
4530 | return linux_ns_same (inf->pid, LINUX_NS_MNT); | |
4531 | } | |
4532 | ||
4533 | /* Convert the INF argument passed to a to_fileio_* method | |
4534 | to a process ID suitable for passing to its corresponding | |
4535 | linux_mntns_* function. If INF is non-NULL then the | |
4536 | caller is requesting the filesystem seen by INF. If INF | |
4537 | is NULL then the caller is requesting the filesystem seen | |
4538 | by the GDB. We fall back to GDB's filesystem in the case | |
4539 | that INF is non-NULL but its PID is unknown. */ | |
4540 | ||
4541 | static pid_t | |
4542 | linux_nat_fileio_pid_of (struct inferior *inf) | |
4543 | { | |
4544 | if (inf == NULL || inf->fake_pid_p || inf->pid == 0) | |
4545 | return getpid (); | |
4546 | else | |
4547 | return inf->pid; | |
4548 | } | |
4549 | ||
4550 | /* Implementation of to_fileio_open. */ | |
4551 | ||
f6ac5f3d PA |
4552 | int |
4553 | linux_nat_target::fileio_open (struct inferior *inf, const char *filename, | |
4554 | int flags, int mode, int warn_if_slow, | |
4555 | int *target_errno) | |
7a6a1731 GB |
4556 | { |
4557 | int nat_flags; | |
4558 | mode_t nat_mode; | |
4559 | int fd; | |
4560 | ||
4561 | if (fileio_to_host_openflags (flags, &nat_flags) == -1 | |
4562 | || fileio_to_host_mode (mode, &nat_mode) == -1) | |
4563 | { | |
4564 | *target_errno = FILEIO_EINVAL; | |
4565 | return -1; | |
4566 | } | |
4567 | ||
4568 | fd = linux_mntns_open_cloexec (linux_nat_fileio_pid_of (inf), | |
4569 | filename, nat_flags, nat_mode); | |
4570 | if (fd == -1) | |
4571 | *target_errno = host_to_fileio_error (errno); | |
4572 | ||
4573 | return fd; | |
4574 | } | |
4575 | ||
4576 | /* Implementation of to_fileio_readlink. */ | |
4577 | ||
f6ac5f3d PA |
4578 | gdb::optional<std::string> |
4579 | linux_nat_target::fileio_readlink (struct inferior *inf, const char *filename, | |
4580 | int *target_errno) | |
7a6a1731 GB |
4581 | { |
4582 | char buf[PATH_MAX]; | |
4583 | int len; | |
7a6a1731 GB |
4584 | |
4585 | len = linux_mntns_readlink (linux_nat_fileio_pid_of (inf), | |
4586 | filename, buf, sizeof (buf)); | |
4587 | if (len < 0) | |
4588 | { | |
4589 | *target_errno = host_to_fileio_error (errno); | |
e0d3522b | 4590 | return {}; |
7a6a1731 GB |
4591 | } |
4592 | ||
e0d3522b | 4593 | return std::string (buf, len); |
7a6a1731 GB |
4594 | } |
4595 | ||
4596 | /* Implementation of to_fileio_unlink. */ | |
4597 | ||
f6ac5f3d PA |
4598 | int |
4599 | linux_nat_target::fileio_unlink (struct inferior *inf, const char *filename, | |
4600 | int *target_errno) | |
7a6a1731 GB |
4601 | { |
4602 | int ret; | |
4603 | ||
4604 | ret = linux_mntns_unlink (linux_nat_fileio_pid_of (inf), | |
4605 | filename); | |
4606 | if (ret == -1) | |
4607 | *target_errno = host_to_fileio_error (errno); | |
4608 | ||
4609 | return ret; | |
4610 | } | |
4611 | ||
aa01bd36 PA |
4612 | /* Implementation of the to_thread_events method. */ |
4613 | ||
f6ac5f3d PA |
4614 | void |
4615 | linux_nat_target::thread_events (int enable) | |
aa01bd36 PA |
4616 | { |
4617 | report_thread_events = enable; | |
4618 | } | |
4619 | ||
f6ac5f3d PA |
4620 | linux_nat_target::linux_nat_target () |
4621 | { | |
f973ed9c DJ |
4622 | /* We don't change the stratum; this target will sit at |
4623 | process_stratum and thread_db will set at thread_stratum. This | |
4624 | is a little strange, since this is a multi-threaded-capable | |
4625 | target, but we want to be on the stack below thread_db, and we | |
4626 | also want to be used for single-threaded processes. */ | |
f973ed9c DJ |
4627 | } |
4628 | ||
f865ee35 JK |
4629 | /* See linux-nat.h. */ |
4630 | ||
4631 | int | |
4632 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4633 | { |
da559b09 | 4634 | int pid; |
9f0bdab8 | 4635 | |
e38504b3 | 4636 | pid = ptid.lwp (); |
da559b09 | 4637 | if (pid == 0) |
e99b03dc | 4638 | pid = ptid.pid (); |
f865ee35 | 4639 | |
da559b09 JK |
4640 | errno = 0; |
4641 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4642 | if (errno != 0) | |
4643 | { | |
4644 | memset (siginfo, 0, sizeof (*siginfo)); | |
4645 | return 0; | |
4646 | } | |
f865ee35 | 4647 | return 1; |
9f0bdab8 DJ |
4648 | } |
4649 | ||
7b669087 GB |
4650 | /* See nat/linux-nat.h. */ |
4651 | ||
4652 | ptid_t | |
4653 | current_lwp_ptid (void) | |
4654 | { | |
15a9e13e | 4655 | gdb_assert (inferior_ptid.lwp_p ()); |
7b669087 GB |
4656 | return inferior_ptid; |
4657 | } | |
4658 | ||
d6b0e80f AC |
4659 | void |
4660 | _initialize_linux_nat (void) | |
4661 | { | |
ccce17b0 YQ |
4662 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4663 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4664 | Set debugging of GNU/Linux lwp module."), _("\ |
4665 | Show debugging of GNU/Linux lwp module."), _("\ | |
4666 | Enables printf debugging output."), | |
ccce17b0 YQ |
4667 | NULL, |
4668 | show_debug_linux_nat, | |
4669 | &setdebuglist, &showdebuglist); | |
b84876c2 | 4670 | |
7a6a1731 GB |
4671 | add_setshow_boolean_cmd ("linux-namespaces", class_maintenance, |
4672 | &debug_linux_namespaces, _("\ | |
4673 | Set debugging of GNU/Linux namespaces module."), _("\ | |
4674 | Show debugging of GNU/Linux namespaces module."), _("\ | |
4675 | Enables printf debugging output."), | |
4676 | NULL, | |
4677 | NULL, | |
4678 | &setdebuglist, &showdebuglist); | |
4679 | ||
b84876c2 | 4680 | /* Save this mask as the default. */ |
d6b0e80f AC |
4681 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4682 | ||
7feb7d06 PA |
4683 | /* Install a SIGCHLD handler. */ |
4684 | sigchld_action.sa_handler = sigchld_handler; | |
4685 | sigemptyset (&sigchld_action.sa_mask); | |
4686 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
4687 | |
4688 | /* Make it the default. */ | |
7feb7d06 | 4689 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
4690 | |
4691 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4692 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4693 | sigdelset (&suspend_mask, SIGCHLD); | |
4694 | ||
7feb7d06 | 4695 | sigemptyset (&blocked_mask); |
774113b0 PA |
4696 | |
4697 | lwp_lwpid_htab_create (); | |
d6b0e80f AC |
4698 | } |
4699 | \f | |
4700 | ||
4701 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4702 | the GNU/Linux Threads library and therefore doesn't really belong | |
4703 | here. */ | |
4704 | ||
d6b0e80f AC |
4705 | /* Return the set of signals used by the threads library in *SET. */ |
4706 | ||
4707 | void | |
4708 | lin_thread_get_thread_signals (sigset_t *set) | |
4709 | { | |
d6b0e80f AC |
4710 | sigemptyset (set); |
4711 | ||
4a6ed09b PA |
4712 | /* NPTL reserves the first two RT signals, but does not provide any |
4713 | way for the debugger to query the signal numbers - fortunately | |
4714 | they don't change. */ | |
4715 | sigaddset (set, __SIGRTMIN); | |
4716 | sigaddset (set, __SIGRTMIN + 1); | |
d6b0e80f | 4717 | } |