Commit | Line | Data |
---|---|---|
3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
32d0add0 | 3 | Copyright (C) 2001-2015 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 | #ifdef HAVE_TKILL_SYSCALL |
28 | #include <unistd.h> | |
29 | #include <sys/syscall.h> | |
30 | #endif | |
3993f6b1 | 31 | #include <sys/ptrace.h> |
0274a8ce | 32 | #include "linux-nat.h" |
125f8a3d GB |
33 | #include "nat/linux-ptrace.h" |
34 | #include "nat/linux-procfs.h" | |
8cc73a39 | 35 | #include "nat/linux-personality.h" |
ac264b3b | 36 | #include "linux-fork.h" |
d6b0e80f AC |
37 | #include "gdbthread.h" |
38 | #include "gdbcmd.h" | |
39 | #include "regcache.h" | |
4f844a66 | 40 | #include "regset.h" |
dab06dbe | 41 | #include "inf-child.h" |
10d6c8cd DJ |
42 | #include "inf-ptrace.h" |
43 | #include "auxv.h" | |
1777feb0 | 44 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
45 | #include "elf-bfd.h" /* for elfcore_write_* */ |
46 | #include "gregset.h" /* for gregset */ | |
47 | #include "gdbcore.h" /* for get_exec_file */ | |
48 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 49 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 50 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
51 | #include "inf-loop.h" |
52 | #include "event-loop.h" | |
53 | #include "event-top.h" | |
07e059b5 VP |
54 | #include <pwd.h> |
55 | #include <sys/types.h> | |
2978b111 | 56 | #include <dirent.h> |
07e059b5 | 57 | #include "xml-support.h" |
efcbbd14 | 58 | #include <sys/vfs.h> |
6c95b8df | 59 | #include "solib.h" |
125f8a3d | 60 | #include "nat/linux-osdata.h" |
6432734d | 61 | #include "linux-tdep.h" |
7dcd53a0 | 62 | #include "symfile.h" |
5808517f YQ |
63 | #include "agent.h" |
64 | #include "tracepoint.h" | |
87b0bb13 | 65 | #include "buffer.h" |
6ecd4729 | 66 | #include "target-descriptions.h" |
614c279d | 67 | #include "filestuff.h" |
77e371c0 | 68 | #include "objfiles.h" |
efcbbd14 UW |
69 | |
70 | #ifndef SPUFS_MAGIC | |
71 | #define SPUFS_MAGIC 0x23c9b64e | |
72 | #endif | |
dba24537 | 73 | |
1777feb0 | 74 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
75 | |
76 | Waiting for events in sync mode | |
77 | =============================== | |
78 | ||
79 | When waiting for an event in a specific thread, we just use waitpid, passing | |
80 | the specific pid, and not passing WNOHANG. | |
81 | ||
1777feb0 | 82 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 83 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 84 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
85 | miss an event. The solution is to use non-blocking waitpid, together with |
86 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 87 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
88 | flag to check for events in cloned processes. If nothing is found, we use |
89 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
90 | happened to a child process -- and SIGCHLD will be delivered both for events | |
91 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
92 | an event, we get back to calling nonblocking waitpid with and without |
93 | __WCLONED. | |
8a77dff3 VP |
94 | |
95 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 96 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
97 | blocked, the signal becomes pending and sigsuspend immediately |
98 | notices it and returns. | |
99 | ||
100 | Waiting for events in async mode | |
101 | ================================ | |
102 | ||
7feb7d06 PA |
103 | In async mode, GDB should always be ready to handle both user input |
104 | and target events, so neither blocking waitpid nor sigsuspend are | |
105 | viable options. Instead, we should asynchronously notify the GDB main | |
106 | event loop whenever there's an unprocessed event from the target. We | |
107 | detect asynchronous target events by handling SIGCHLD signals. To | |
108 | notify the event loop about target events, the self-pipe trick is used | |
109 | --- a pipe is registered as waitable event source in the event loop, | |
110 | the event loop select/poll's on the read end of this pipe (as well on | |
111 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
112 | byte to this pipe. This is more portable than relying on | |
113 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
114 | emulates them with select/poll+sigprocmask, and that is racy | |
115 | (a.k.a. plain broken). | |
116 | ||
117 | Obviously, if we fail to notify the event loop if there's a target | |
118 | event, it's bad. OTOH, if we notify the event loop when there's no | |
119 | event from the target, linux_nat_wait will detect that there's no real | |
120 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
121 | This is mostly harmless, but it will waste time and is better avoided. | |
122 | ||
123 | The main design point is that every time GDB is outside linux-nat.c, | |
124 | we have a SIGCHLD handler installed that is called when something | |
125 | happens to the target and notifies the GDB event loop. Whenever GDB | |
126 | core decides to handle the event, and calls into linux-nat.c, we | |
127 | process things as in sync mode, except that the we never block in | |
128 | sigsuspend. | |
129 | ||
130 | While processing an event, we may end up momentarily blocked in | |
131 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
132 | return quickly. E.g., in all-stop mode, before reporting to the core | |
133 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
134 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
135 | Note that this is different from blocking indefinitely waiting for the | |
136 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
137 | |
138 | Use of signals | |
139 | ============== | |
140 | ||
141 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
142 | signal is not entirely significant; we just need for a signal to be delivered, | |
143 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
144 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
145 | be queued once; we do not keep track of other sources of SIGSTOP. | |
146 | ||
147 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
148 | use them, because they have special behavior when the signal is generated - | |
149 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
150 | kills the entire thread group. | |
151 | ||
152 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
153 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
154 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
155 | ||
156 | We could use a real-time signal instead. This would solve those problems; we | |
157 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
158 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
159 | generates it, and there are races with trying to find a signal that is not | |
160 | blocked. */ | |
a0ef4274 | 161 | |
dba24537 AC |
162 | #ifndef O_LARGEFILE |
163 | #define O_LARGEFILE 0 | |
164 | #endif | |
0274a8ce | 165 | |
10d6c8cd DJ |
166 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
167 | the use of the multi-threaded target. */ | |
168 | static struct target_ops *linux_ops; | |
f973ed9c | 169 | static struct target_ops linux_ops_saved; |
10d6c8cd | 170 | |
9f0bdab8 | 171 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
172 | static void (*linux_nat_new_thread) (struct lwp_info *); |
173 | ||
26cb8b7c PA |
174 | /* The method to call, if any, when a new fork is attached. */ |
175 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
176 | ||
177 | /* The method to call, if any, when a process is no longer | |
178 | attached. */ | |
179 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
180 | ||
7b50312a PA |
181 | /* Hook to call prior to resuming a thread. */ |
182 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 183 | |
5b009018 PA |
184 | /* The method to call, if any, when the siginfo object needs to be |
185 | converted between the layout returned by ptrace, and the layout in | |
186 | the architecture of the inferior. */ | |
a5362b9a | 187 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
188 | gdb_byte *, |
189 | int); | |
190 | ||
ac264b3b MS |
191 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
192 | Called by our to_xfer_partial. */ | |
4ac248ca | 193 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 194 | |
6a3cb8e8 PA |
195 | /* The saved to_close method, inherited from inf-ptrace.c. |
196 | Called by our to_close. */ | |
197 | static void (*super_close) (struct target_ops *); | |
198 | ||
ccce17b0 | 199 | static unsigned int debug_linux_nat; |
920d2a44 AC |
200 | static void |
201 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
202 | struct cmd_list_element *c, const char *value) | |
203 | { | |
204 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
205 | value); | |
206 | } | |
d6b0e80f | 207 | |
ae087d01 DJ |
208 | struct simple_pid_list |
209 | { | |
210 | int pid; | |
3d799a95 | 211 | int status; |
ae087d01 DJ |
212 | struct simple_pid_list *next; |
213 | }; | |
214 | struct simple_pid_list *stopped_pids; | |
215 | ||
3dd5b83d PA |
216 | /* Async mode support. */ |
217 | ||
b84876c2 PA |
218 | /* The read/write ends of the pipe registered as waitable file in the |
219 | event loop. */ | |
220 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
221 | ||
198297aa PA |
222 | /* True if we're currently in async mode. */ |
223 | #define linux_is_async_p() (linux_nat_event_pipe[0] != -1) | |
224 | ||
7feb7d06 | 225 | /* Flush the event pipe. */ |
b84876c2 | 226 | |
7feb7d06 PA |
227 | static void |
228 | async_file_flush (void) | |
b84876c2 | 229 | { |
7feb7d06 PA |
230 | int ret; |
231 | char buf; | |
b84876c2 | 232 | |
7feb7d06 | 233 | do |
b84876c2 | 234 | { |
7feb7d06 | 235 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 236 | } |
7feb7d06 | 237 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
238 | } |
239 | ||
7feb7d06 PA |
240 | /* Put something (anything, doesn't matter what, or how much) in event |
241 | pipe, so that the select/poll in the event-loop realizes we have | |
242 | something to process. */ | |
252fbfc8 | 243 | |
b84876c2 | 244 | static void |
7feb7d06 | 245 | async_file_mark (void) |
b84876c2 | 246 | { |
7feb7d06 | 247 | int ret; |
b84876c2 | 248 | |
7feb7d06 PA |
249 | /* It doesn't really matter what the pipe contains, as long we end |
250 | up with something in it. Might as well flush the previous | |
251 | left-overs. */ | |
252 | async_file_flush (); | |
b84876c2 | 253 | |
7feb7d06 | 254 | do |
b84876c2 | 255 | { |
7feb7d06 | 256 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 257 | } |
7feb7d06 | 258 | while (ret == -1 && errno == EINTR); |
b84876c2 | 259 | |
7feb7d06 PA |
260 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
261 | be awakened anyway. */ | |
b84876c2 PA |
262 | } |
263 | ||
7feb7d06 PA |
264 | static int kill_lwp (int lwpid, int signo); |
265 | ||
266 | static int stop_callback (struct lwp_info *lp, void *data); | |
2db9a427 | 267 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
7feb7d06 PA |
268 | |
269 | static void block_child_signals (sigset_t *prev_mask); | |
270 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
271 | |
272 | struct lwp_info; | |
273 | static struct lwp_info *add_lwp (ptid_t ptid); | |
274 | static void purge_lwp_list (int pid); | |
4403d8e9 | 275 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
276 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
277 | ||
8a99810d PA |
278 | static int lwp_status_pending_p (struct lwp_info *lp); |
279 | ||
9c02b525 PA |
280 | static int check_stopped_by_breakpoint (struct lwp_info *lp); |
281 | static int sigtrap_is_event (int status); | |
282 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
283 | ||
cff068da GB |
284 | \f |
285 | /* LWP accessors. */ | |
286 | ||
287 | /* See nat/linux-nat.h. */ | |
288 | ||
289 | ptid_t | |
290 | ptid_of_lwp (struct lwp_info *lwp) | |
291 | { | |
292 | return lwp->ptid; | |
293 | } | |
294 | ||
295 | /* See nat/linux-nat.h. */ | |
296 | ||
4b134ca1 GB |
297 | void |
298 | lwp_set_arch_private_info (struct lwp_info *lwp, | |
299 | struct arch_lwp_info *info) | |
300 | { | |
301 | lwp->arch_private = info; | |
302 | } | |
303 | ||
304 | /* See nat/linux-nat.h. */ | |
305 | ||
306 | struct arch_lwp_info * | |
307 | lwp_arch_private_info (struct lwp_info *lwp) | |
308 | { | |
309 | return lwp->arch_private; | |
310 | } | |
311 | ||
312 | /* See nat/linux-nat.h. */ | |
313 | ||
cff068da GB |
314 | int |
315 | lwp_is_stopped (struct lwp_info *lwp) | |
316 | { | |
317 | return lwp->stopped; | |
318 | } | |
319 | ||
320 | /* See nat/linux-nat.h. */ | |
321 | ||
322 | enum target_stop_reason | |
323 | lwp_stop_reason (struct lwp_info *lwp) | |
324 | { | |
325 | return lwp->stop_reason; | |
326 | } | |
327 | ||
ae087d01 DJ |
328 | \f |
329 | /* Trivial list manipulation functions to keep track of a list of | |
330 | new stopped processes. */ | |
331 | static void | |
3d799a95 | 332 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
333 | { |
334 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 335 | |
ae087d01 | 336 | new_pid->pid = pid; |
3d799a95 | 337 | new_pid->status = status; |
ae087d01 DJ |
338 | new_pid->next = *listp; |
339 | *listp = new_pid; | |
340 | } | |
341 | ||
84636d28 PA |
342 | static int |
343 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
344 | { | |
345 | struct simple_pid_list *p; | |
346 | ||
347 | for (p = list; p != NULL; p = p->next) | |
348 | if (p->pid == pid) | |
349 | return 1; | |
350 | return 0; | |
351 | } | |
352 | ||
ae087d01 | 353 | static int |
46a96992 | 354 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
355 | { |
356 | struct simple_pid_list **p; | |
357 | ||
358 | for (p = listp; *p != NULL; p = &(*p)->next) | |
359 | if ((*p)->pid == pid) | |
360 | { | |
361 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 362 | |
46a96992 | 363 | *statusp = (*p)->status; |
ae087d01 DJ |
364 | xfree (*p); |
365 | *p = next; | |
366 | return 1; | |
367 | } | |
368 | return 0; | |
369 | } | |
370 | ||
de0d863e DB |
371 | /* Return the ptrace options that we want to try to enable. */ |
372 | ||
373 | static int | |
374 | linux_nat_ptrace_options (int attached) | |
375 | { | |
376 | int options = 0; | |
377 | ||
378 | if (!attached) | |
379 | options |= PTRACE_O_EXITKILL; | |
380 | ||
381 | options |= (PTRACE_O_TRACESYSGOOD | |
382 | | PTRACE_O_TRACEVFORKDONE | |
383 | | PTRACE_O_TRACEVFORK | |
384 | | PTRACE_O_TRACEFORK | |
385 | | PTRACE_O_TRACEEXEC); | |
386 | ||
387 | return options; | |
388 | } | |
389 | ||
96d7229d | 390 | /* Initialize ptrace warnings and check for supported ptrace |
beed38b8 JB |
391 | features given PID. |
392 | ||
393 | ATTACHED should be nonzero iff we attached to the inferior. */ | |
3993f6b1 DJ |
394 | |
395 | static void | |
beed38b8 | 396 | linux_init_ptrace (pid_t pid, int attached) |
3993f6b1 | 397 | { |
de0d863e DB |
398 | int options = linux_nat_ptrace_options (attached); |
399 | ||
400 | linux_enable_event_reporting (pid, options); | |
96d7229d | 401 | linux_ptrace_init_warnings (); |
4de4c07c DJ |
402 | } |
403 | ||
6d8fd2b7 | 404 | static void |
f045800c | 405 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 406 | { |
beed38b8 | 407 | linux_init_ptrace (pid, 1); |
4de4c07c DJ |
408 | } |
409 | ||
10d6c8cd | 410 | static void |
2e97a79e | 411 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 412 | { |
beed38b8 | 413 | linux_init_ptrace (ptid_get_pid (ptid), 0); |
4de4c07c DJ |
414 | } |
415 | ||
4403d8e9 JK |
416 | /* Return the number of known LWPs in the tgid given by PID. */ |
417 | ||
418 | static int | |
419 | num_lwps (int pid) | |
420 | { | |
421 | int count = 0; | |
422 | struct lwp_info *lp; | |
423 | ||
424 | for (lp = lwp_list; lp; lp = lp->next) | |
425 | if (ptid_get_pid (lp->ptid) == pid) | |
426 | count++; | |
427 | ||
428 | return count; | |
429 | } | |
430 | ||
431 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
432 | ||
433 | static void | |
434 | delete_lwp_cleanup (void *lp_voidp) | |
435 | { | |
436 | struct lwp_info *lp = lp_voidp; | |
437 | ||
438 | delete_lwp (lp->ptid); | |
439 | } | |
440 | ||
d83ad864 DB |
441 | /* Target hook for follow_fork. On entry inferior_ptid must be the |
442 | ptid of the followed inferior. At return, inferior_ptid will be | |
443 | unchanged. */ | |
444 | ||
6d8fd2b7 | 445 | static int |
07107ca6 LM |
446 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
447 | int detach_fork) | |
3993f6b1 | 448 | { |
d83ad864 | 449 | if (!follow_child) |
4de4c07c | 450 | { |
6c95b8df | 451 | struct lwp_info *child_lp = NULL; |
d83ad864 DB |
452 | int status = W_STOPCODE (0); |
453 | struct cleanup *old_chain; | |
454 | int has_vforked; | |
79639e11 | 455 | ptid_t parent_ptid, child_ptid; |
d83ad864 DB |
456 | int parent_pid, child_pid; |
457 | ||
458 | has_vforked = (inferior_thread ()->pending_follow.kind | |
459 | == TARGET_WAITKIND_VFORKED); | |
79639e11 PA |
460 | parent_ptid = inferior_ptid; |
461 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; | |
462 | parent_pid = ptid_get_lwp (parent_ptid); | |
463 | child_pid = ptid_get_lwp (child_ptid); | |
4de4c07c | 464 | |
1777feb0 | 465 | /* We're already attached to the parent, by default. */ |
d83ad864 | 466 | old_chain = save_inferior_ptid (); |
79639e11 | 467 | inferior_ptid = child_ptid; |
d83ad864 DB |
468 | child_lp = add_lwp (inferior_ptid); |
469 | child_lp->stopped = 1; | |
470 | child_lp->last_resume_kind = resume_stop; | |
4de4c07c | 471 | |
ac264b3b MS |
472 | /* Detach new forked process? */ |
473 | if (detach_fork) | |
f75c00e4 | 474 | { |
4403d8e9 JK |
475 | make_cleanup (delete_lwp_cleanup, child_lp); |
476 | ||
4403d8e9 JK |
477 | if (linux_nat_prepare_to_resume != NULL) |
478 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
479 | |
480 | /* When debugging an inferior in an architecture that supports | |
481 | hardware single stepping on a kernel without commit | |
482 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
483 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
484 | set if the parent process had them set. | |
485 | To work around this, single step the child process | |
486 | once before detaching to clear the flags. */ | |
487 | ||
488 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
489 | (child_lp->ptid))) | |
490 | { | |
c077881a HZ |
491 | linux_disable_event_reporting (child_pid); |
492 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
493 | perror_with_name (_("Couldn't do single step")); | |
494 | if (my_waitpid (child_pid, &status, 0) < 0) | |
495 | perror_with_name (_("Couldn't wait vfork process")); | |
496 | } | |
497 | ||
498 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
499 | { |
500 | int signo; | |
501 | ||
502 | signo = WSTOPSIG (status); | |
503 | if (signo != 0 | |
504 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
505 | signo = 0; | |
506 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
507 | } | |
4403d8e9 | 508 | |
d83ad864 | 509 | /* Resets value of inferior_ptid to parent ptid. */ |
4403d8e9 | 510 | do_cleanups (old_chain); |
ac264b3b MS |
511 | } |
512 | else | |
513 | { | |
6c95b8df | 514 | /* Let the thread_db layer learn about this new process. */ |
2277426b | 515 | check_for_thread_db (); |
ac264b3b | 516 | } |
9016a515 | 517 | |
d83ad864 DB |
518 | do_cleanups (old_chain); |
519 | ||
9016a515 DJ |
520 | if (has_vforked) |
521 | { | |
3ced3da4 | 522 | struct lwp_info *parent_lp; |
6c95b8df | 523 | |
79639e11 | 524 | parent_lp = find_lwp_pid (parent_ptid); |
96d7229d | 525 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 526 | |
96d7229d | 527 | if (linux_supports_tracevforkdone ()) |
9016a515 | 528 | { |
6c95b8df PA |
529 | if (debug_linux_nat) |
530 | fprintf_unfiltered (gdb_stdlog, | |
531 | "LCFF: waiting for VFORK_DONE on %d\n", | |
532 | parent_pid); | |
3ced3da4 | 533 | parent_lp->stopped = 1; |
9016a515 | 534 | |
6c95b8df PA |
535 | /* We'll handle the VFORK_DONE event like any other |
536 | event, in target_wait. */ | |
9016a515 DJ |
537 | } |
538 | else | |
539 | { | |
540 | /* We can't insert breakpoints until the child has | |
541 | finished with the shared memory region. We need to | |
542 | wait until that happens. Ideal would be to just | |
543 | call: | |
544 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
545 | - waitpid (parent_pid, &status, __WALL); | |
546 | However, most architectures can't handle a syscall | |
547 | being traced on the way out if it wasn't traced on | |
548 | the way in. | |
549 | ||
550 | We might also think to loop, continuing the child | |
551 | until it exits or gets a SIGTRAP. One problem is | |
552 | that the child might call ptrace with PTRACE_TRACEME. | |
553 | ||
554 | There's no simple and reliable way to figure out when | |
555 | the vforked child will be done with its copy of the | |
556 | shared memory. We could step it out of the syscall, | |
557 | two instructions, let it go, and then single-step the | |
558 | parent once. When we have hardware single-step, this | |
559 | would work; with software single-step it could still | |
560 | be made to work but we'd have to be able to insert | |
561 | single-step breakpoints in the child, and we'd have | |
562 | to insert -just- the single-step breakpoint in the | |
563 | parent. Very awkward. | |
564 | ||
565 | In the end, the best we can do is to make sure it | |
566 | runs for a little while. Hopefully it will be out of | |
567 | range of any breakpoints we reinsert. Usually this | |
568 | is only the single-step breakpoint at vfork's return | |
569 | point. */ | |
570 | ||
6c95b8df PA |
571 | if (debug_linux_nat) |
572 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
573 | "LCFF: no VFORK_DONE " |
574 | "support, sleeping a bit\n"); | |
6c95b8df | 575 | |
9016a515 | 576 | usleep (10000); |
9016a515 | 577 | |
6c95b8df PA |
578 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
579 | and leave it pending. The next linux_nat_resume call | |
580 | will notice a pending event, and bypasses actually | |
581 | resuming the inferior. */ | |
3ced3da4 PA |
582 | parent_lp->status = 0; |
583 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
584 | parent_lp->stopped = 1; | |
6c95b8df PA |
585 | |
586 | /* If we're in async mode, need to tell the event loop | |
587 | there's something here to process. */ | |
d9d41e78 | 588 | if (target_is_async_p ()) |
6c95b8df PA |
589 | async_file_mark (); |
590 | } | |
9016a515 | 591 | } |
4de4c07c | 592 | } |
3993f6b1 | 593 | else |
4de4c07c | 594 | { |
3ced3da4 | 595 | struct lwp_info *child_lp; |
4de4c07c | 596 | |
3ced3da4 PA |
597 | child_lp = add_lwp (inferior_ptid); |
598 | child_lp->stopped = 1; | |
25289eb2 | 599 | child_lp->last_resume_kind = resume_stop; |
6c95b8df | 600 | |
6c95b8df | 601 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 602 | check_for_thread_db (); |
4de4c07c DJ |
603 | } |
604 | ||
605 | return 0; | |
606 | } | |
607 | ||
4de4c07c | 608 | \f |
77b06cd7 | 609 | static int |
a863b201 | 610 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 611 | { |
96d7229d | 612 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
613 | } |
614 | ||
eb73ad13 | 615 | static int |
973fc227 | 616 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
617 | { |
618 | return 0; | |
619 | } | |
620 | ||
77b06cd7 | 621 | static int |
3ecc7da0 | 622 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 623 | { |
96d7229d | 624 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
625 | } |
626 | ||
eb73ad13 | 627 | static int |
e98cf0cd | 628 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
629 | { |
630 | return 0; | |
631 | } | |
632 | ||
77b06cd7 | 633 | static int |
ba025e51 | 634 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 635 | { |
96d7229d | 636 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
637 | } |
638 | ||
eb73ad13 | 639 | static int |
758e29d2 | 640 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
641 | { |
642 | return 0; | |
643 | } | |
644 | ||
a96d9b2e | 645 | static int |
ff214e67 TT |
646 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
647 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
648 | int table_size, int *table) |
649 | { | |
96d7229d | 650 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
651 | return 1; |
652 | ||
a96d9b2e SDJ |
653 | /* On GNU/Linux, we ignore the arguments. It means that we only |
654 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 655 | |
a96d9b2e SDJ |
656 | Also, we do not use the `table' information because we do not |
657 | filter system calls here. We let GDB do the logic for us. */ | |
658 | return 0; | |
659 | } | |
660 | ||
d6b0e80f AC |
661 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
662 | are processes sharing the same VM space. A multi-threaded process | |
663 | is basically a group of such processes. However, such a grouping | |
664 | is almost entirely a user-space issue; the kernel doesn't enforce | |
665 | such a grouping at all (this might change in the future). In | |
666 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
667 | Threads library) to provide such a grouping. | |
668 | ||
669 | It is perfectly well possible to write a multi-threaded application | |
670 | without the assistance of a threads library, by using the clone | |
671 | system call directly. This module should be able to give some | |
672 | rudimentary support for debugging such applications if developers | |
673 | specify the CLONE_PTRACE flag in the clone system call, and are | |
674 | using the Linux kernel 2.4 or above. | |
675 | ||
676 | Note that there are some peculiarities in GNU/Linux that affect | |
677 | this code: | |
678 | ||
679 | - In general one should specify the __WCLONE flag to waitpid in | |
680 | order to make it report events for any of the cloned processes | |
681 | (and leave it out for the initial process). However, if a cloned | |
682 | process has exited the exit status is only reported if the | |
683 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
684 | we cannot use it since GDB must work on older systems too. | |
685 | ||
686 | - When a traced, cloned process exits and is waited for by the | |
687 | debugger, the kernel reassigns it to the original parent and | |
688 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
689 | library doesn't notice this, which leads to the "zombie problem": | |
690 | When debugged a multi-threaded process that spawns a lot of | |
691 | threads will run out of processes, even if the threads exit, | |
692 | because the "zombies" stay around. */ | |
693 | ||
694 | /* List of known LWPs. */ | |
9f0bdab8 | 695 | struct lwp_info *lwp_list; |
d6b0e80f AC |
696 | \f |
697 | ||
d6b0e80f AC |
698 | /* Original signal mask. */ |
699 | static sigset_t normal_mask; | |
700 | ||
701 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
702 | _initialize_linux_nat. */ | |
703 | static sigset_t suspend_mask; | |
704 | ||
7feb7d06 PA |
705 | /* Signals to block to make that sigsuspend work. */ |
706 | static sigset_t blocked_mask; | |
707 | ||
708 | /* SIGCHLD action. */ | |
709 | struct sigaction sigchld_action; | |
b84876c2 | 710 | |
7feb7d06 PA |
711 | /* Block child signals (SIGCHLD and linux threads signals), and store |
712 | the previous mask in PREV_MASK. */ | |
84e46146 | 713 | |
7feb7d06 PA |
714 | static void |
715 | block_child_signals (sigset_t *prev_mask) | |
716 | { | |
717 | /* Make sure SIGCHLD is blocked. */ | |
718 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
719 | sigaddset (&blocked_mask, SIGCHLD); | |
720 | ||
721 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
722 | } | |
723 | ||
724 | /* Restore child signals mask, previously returned by | |
725 | block_child_signals. */ | |
726 | ||
727 | static void | |
728 | restore_child_signals_mask (sigset_t *prev_mask) | |
729 | { | |
730 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
731 | } | |
2455069d UW |
732 | |
733 | /* Mask of signals to pass directly to the inferior. */ | |
734 | static sigset_t pass_mask; | |
735 | ||
736 | /* Update signals to pass to the inferior. */ | |
737 | static void | |
94bedb42 TT |
738 | linux_nat_pass_signals (struct target_ops *self, |
739 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
740 | { |
741 | int signo; | |
742 | ||
743 | sigemptyset (&pass_mask); | |
744 | ||
745 | for (signo = 1; signo < NSIG; signo++) | |
746 | { | |
2ea28649 | 747 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
748 | if (target_signo < numsigs && pass_signals[target_signo]) |
749 | sigaddset (&pass_mask, signo); | |
750 | } | |
751 | } | |
752 | ||
d6b0e80f AC |
753 | \f |
754 | ||
755 | /* Prototypes for local functions. */ | |
756 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 757 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 758 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
20ba1ce6 | 759 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
710151dd | 760 | |
d6b0e80f | 761 | \f |
d6b0e80f | 762 | |
7b50312a PA |
763 | /* Destroy and free LP. */ |
764 | ||
765 | static void | |
766 | lwp_free (struct lwp_info *lp) | |
767 | { | |
768 | xfree (lp->arch_private); | |
769 | xfree (lp); | |
770 | } | |
771 | ||
d90e17a7 PA |
772 | /* Remove all LWPs belong to PID from the lwp list. */ |
773 | ||
774 | static void | |
775 | purge_lwp_list (int pid) | |
776 | { | |
777 | struct lwp_info *lp, *lpprev, *lpnext; | |
778 | ||
779 | lpprev = NULL; | |
780 | ||
781 | for (lp = lwp_list; lp; lp = lpnext) | |
782 | { | |
783 | lpnext = lp->next; | |
784 | ||
785 | if (ptid_get_pid (lp->ptid) == pid) | |
786 | { | |
787 | if (lp == lwp_list) | |
788 | lwp_list = lp->next; | |
789 | else | |
790 | lpprev->next = lp->next; | |
791 | ||
7b50312a | 792 | lwp_free (lp); |
d90e17a7 PA |
793 | } |
794 | else | |
795 | lpprev = lp; | |
796 | } | |
797 | } | |
798 | ||
26cb8b7c PA |
799 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
800 | in the process. Return a pointer to the structure describing the | |
801 | new LWP. | |
802 | ||
803 | This differs from add_lwp in that we don't let the arch specific | |
804 | bits know about this new thread. Current clients of this callback | |
805 | take the opportunity to install watchpoints in the new thread, and | |
806 | we shouldn't do that for the first thread. If we're spawning a | |
807 | child ("run"), the thread executes the shell wrapper first, and we | |
808 | shouldn't touch it until it execs the program we want to debug. | |
809 | For "attach", it'd be okay to call the callback, but it's not | |
810 | necessary, because watchpoints can't yet have been inserted into | |
811 | the inferior. */ | |
d6b0e80f AC |
812 | |
813 | static struct lwp_info * | |
26cb8b7c | 814 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
815 | { |
816 | struct lwp_info *lp; | |
817 | ||
dfd4cc63 | 818 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
819 | |
820 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
821 | ||
822 | memset (lp, 0, sizeof (struct lwp_info)); | |
823 | ||
25289eb2 | 824 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
825 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
826 | ||
827 | lp->ptid = ptid; | |
dc146f7c | 828 | lp->core = -1; |
d6b0e80f AC |
829 | |
830 | lp->next = lwp_list; | |
831 | lwp_list = lp; | |
d6b0e80f | 832 | |
26cb8b7c PA |
833 | return lp; |
834 | } | |
835 | ||
836 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
837 | structure describing the new LWP. The LWP should already be | |
838 | stopped. */ | |
839 | ||
840 | static struct lwp_info * | |
841 | add_lwp (ptid_t ptid) | |
842 | { | |
843 | struct lwp_info *lp; | |
844 | ||
845 | lp = add_initial_lwp (ptid); | |
846 | ||
6e012a6c PA |
847 | /* Let the arch specific bits know about this new thread. Current |
848 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
849 | watchpoints in the new thread. We don't do this for the first |
850 | thread though. See add_initial_lwp. */ | |
851 | if (linux_nat_new_thread != NULL) | |
7b50312a | 852 | linux_nat_new_thread (lp); |
9f0bdab8 | 853 | |
d6b0e80f AC |
854 | return lp; |
855 | } | |
856 | ||
857 | /* Remove the LWP specified by PID from the list. */ | |
858 | ||
859 | static void | |
860 | delete_lwp (ptid_t ptid) | |
861 | { | |
862 | struct lwp_info *lp, *lpprev; | |
863 | ||
864 | lpprev = NULL; | |
865 | ||
866 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
867 | if (ptid_equal (lp->ptid, ptid)) | |
868 | break; | |
869 | ||
870 | if (!lp) | |
871 | return; | |
872 | ||
d6b0e80f AC |
873 | if (lpprev) |
874 | lpprev->next = lp->next; | |
875 | else | |
876 | lwp_list = lp->next; | |
877 | ||
7b50312a | 878 | lwp_free (lp); |
d6b0e80f AC |
879 | } |
880 | ||
881 | /* Return a pointer to the structure describing the LWP corresponding | |
882 | to PID. If no corresponding LWP could be found, return NULL. */ | |
883 | ||
884 | static struct lwp_info * | |
885 | find_lwp_pid (ptid_t ptid) | |
886 | { | |
887 | struct lwp_info *lp; | |
888 | int lwp; | |
889 | ||
dfd4cc63 LM |
890 | if (ptid_lwp_p (ptid)) |
891 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 892 | else |
dfd4cc63 | 893 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
894 | |
895 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 896 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
897 | return lp; |
898 | ||
899 | return NULL; | |
900 | } | |
901 | ||
6d4ee8c6 | 902 | /* See nat/linux-nat.h. */ |
d6b0e80f AC |
903 | |
904 | struct lwp_info * | |
d90e17a7 | 905 | iterate_over_lwps (ptid_t filter, |
6d4ee8c6 | 906 | iterate_over_lwps_ftype callback, |
d90e17a7 | 907 | void *data) |
d6b0e80f AC |
908 | { |
909 | struct lwp_info *lp, *lpnext; | |
910 | ||
911 | for (lp = lwp_list; lp; lp = lpnext) | |
912 | { | |
913 | lpnext = lp->next; | |
d90e17a7 PA |
914 | |
915 | if (ptid_match (lp->ptid, filter)) | |
916 | { | |
6d4ee8c6 | 917 | if ((*callback) (lp, data) != 0) |
d90e17a7 PA |
918 | return lp; |
919 | } | |
d6b0e80f AC |
920 | } |
921 | ||
922 | return NULL; | |
923 | } | |
924 | ||
2277426b PA |
925 | /* Update our internal state when changing from one checkpoint to |
926 | another indicated by NEW_PTID. We can only switch single-threaded | |
927 | applications, so we only create one new LWP, and the previous list | |
928 | is discarded. */ | |
f973ed9c DJ |
929 | |
930 | void | |
931 | linux_nat_switch_fork (ptid_t new_ptid) | |
932 | { | |
933 | struct lwp_info *lp; | |
934 | ||
dfd4cc63 | 935 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 936 | |
f973ed9c DJ |
937 | lp = add_lwp (new_ptid); |
938 | lp->stopped = 1; | |
e26af52f | 939 | |
2277426b PA |
940 | /* This changes the thread's ptid while preserving the gdb thread |
941 | num. Also changes the inferior pid, while preserving the | |
942 | inferior num. */ | |
943 | thread_change_ptid (inferior_ptid, new_ptid); | |
944 | ||
945 | /* We've just told GDB core that the thread changed target id, but, | |
946 | in fact, it really is a different thread, with different register | |
947 | contents. */ | |
948 | registers_changed (); | |
e26af52f DJ |
949 | } |
950 | ||
e26af52f DJ |
951 | /* Handle the exit of a single thread LP. */ |
952 | ||
953 | static void | |
954 | exit_lwp (struct lwp_info *lp) | |
955 | { | |
e09875d4 | 956 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
957 | |
958 | if (th) | |
e26af52f | 959 | { |
17faa917 DJ |
960 | if (print_thread_events) |
961 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
962 | ||
4f8d22e3 | 963 | delete_thread (lp->ptid); |
e26af52f DJ |
964 | } |
965 | ||
966 | delete_lwp (lp->ptid); | |
967 | } | |
968 | ||
a0ef4274 DJ |
969 | /* Wait for the LWP specified by LP, which we have just attached to. |
970 | Returns a wait status for that LWP, to cache. */ | |
971 | ||
972 | static int | |
973 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
974 | int *signalled) | |
975 | { | |
dfd4cc63 | 976 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
977 | int status; |
978 | ||
644cebc9 | 979 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
980 | { |
981 | if (debug_linux_nat) | |
982 | fprintf_unfiltered (gdb_stdlog, | |
983 | "LNPAW: Attaching to a stopped process\n"); | |
984 | ||
985 | /* The process is definitely stopped. It is in a job control | |
986 | stop, unless the kernel predates the TASK_STOPPED / | |
987 | TASK_TRACED distinction, in which case it might be in a | |
988 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
989 | can kill it, signal it, et cetera. | |
990 | ||
991 | First make sure there is a pending SIGSTOP. Since we are | |
992 | already attached, the process can not transition from stopped | |
993 | to running without a PTRACE_CONT; so we know this signal will | |
994 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
995 | probably already in the queue (unless this kernel is old | |
996 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
997 | is not an RT signal, it can only be queued once. */ | |
998 | kill_lwp (pid, SIGSTOP); | |
999 | ||
1000 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1001 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1002 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1003 | } | |
1004 | ||
1005 | /* Make sure the initial process is stopped. The user-level threads | |
1006 | layer might want to poke around in the inferior, and that won't | |
1007 | work if things haven't stabilized yet. */ | |
1008 | new_pid = my_waitpid (pid, &status, 0); | |
1009 | if (new_pid == -1 && errno == ECHILD) | |
1010 | { | |
1011 | if (first) | |
1012 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1013 | ||
1014 | /* Try again with __WCLONE to check cloned processes. */ | |
1015 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1016 | *cloned = 1; | |
1017 | } | |
1018 | ||
dacc9cb2 PP |
1019 | gdb_assert (pid == new_pid); |
1020 | ||
1021 | if (!WIFSTOPPED (status)) | |
1022 | { | |
1023 | /* The pid we tried to attach has apparently just exited. */ | |
1024 | if (debug_linux_nat) | |
1025 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1026 | pid, status_to_str (status)); | |
1027 | return status; | |
1028 | } | |
a0ef4274 DJ |
1029 | |
1030 | if (WSTOPSIG (status) != SIGSTOP) | |
1031 | { | |
1032 | *signalled = 1; | |
1033 | if (debug_linux_nat) | |
1034 | fprintf_unfiltered (gdb_stdlog, | |
1035 | "LNPAW: Received %s after attaching\n", | |
1036 | status_to_str (status)); | |
1037 | } | |
1038 | ||
1039 | return status; | |
1040 | } | |
1041 | ||
84636d28 PA |
1042 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1043 | the new LWP could not be attached, or 1 if we're already auto | |
1044 | attached to this thread, but haven't processed the | |
1045 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1046 | its existance, without considering it an error. */ | |
d6b0e80f | 1047 | |
9ee57c33 | 1048 | int |
93815fbf | 1049 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1050 | { |
9ee57c33 | 1051 | struct lwp_info *lp; |
84636d28 | 1052 | int lwpid; |
d6b0e80f | 1053 | |
dfd4cc63 | 1054 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1055 | |
9ee57c33 | 1056 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1057 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f | 1058 | |
3b27ef47 | 1059 | /* We assume that we're already attached to any LWP that is already |
d6b0e80f AC |
1060 | in our list of LWPs. If we're not seeing exit events from threads |
1061 | and we've had PID wraparound since we last tried to stop all threads, | |
1062 | this assumption might be wrong; fortunately, this is very unlikely | |
1063 | to happen. */ | |
3b27ef47 | 1064 | if (lp == NULL) |
d6b0e80f | 1065 | { |
a0ef4274 | 1066 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1067 | |
84636d28 | 1068 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1069 | { |
96d7229d | 1070 | if (linux_supports_tracefork ()) |
84636d28 PA |
1071 | { |
1072 | /* If we haven't stopped all threads when we get here, | |
1073 | we may have seen a thread listed in thread_db's list, | |
1074 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1075 | that's the case, ignore this new thread, and let | |
1076 | normal event handling discover it later. */ | |
1077 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1078 | { | |
1079 | /* We've already seen this thread stop, but we | |
1080 | haven't seen the PTRACE_EVENT_CLONE extended | |
1081 | event yet. */ | |
3b27ef47 PA |
1082 | if (debug_linux_nat) |
1083 | fprintf_unfiltered (gdb_stdlog, | |
1084 | "LLAL: attach failed, but already seen " | |
1085 | "this thread %s stop\n", | |
1086 | target_pid_to_str (ptid)); | |
1087 | return 1; | |
84636d28 PA |
1088 | } |
1089 | else | |
1090 | { | |
1091 | int new_pid; | |
1092 | int status; | |
1093 | ||
3b27ef47 PA |
1094 | if (debug_linux_nat) |
1095 | fprintf_unfiltered (gdb_stdlog, | |
1096 | "LLAL: attach failed, and haven't seen " | |
1097 | "this thread %s stop yet\n", | |
1098 | target_pid_to_str (ptid)); | |
1099 | ||
1100 | /* We may or may not be attached to the LWP already. | |
1101 | Try waitpid on it. If that errors, we're not | |
1102 | attached to the LWP yet. Otherwise, we're | |
1103 | already attached. */ | |
a33e3959 | 1104 | gdb_assert (lwpid > 0); |
84636d28 PA |
1105 | new_pid = my_waitpid (lwpid, &status, WNOHANG); |
1106 | if (new_pid == -1 && errno == ECHILD) | |
1107 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1108 | if (new_pid != -1) | |
1109 | { | |
3b27ef47 PA |
1110 | if (new_pid == 0) |
1111 | { | |
1112 | /* The child hasn't stopped for its initial | |
1113 | SIGSTOP stop yet. */ | |
1114 | if (debug_linux_nat) | |
1115 | fprintf_unfiltered (gdb_stdlog, | |
1116 | "LLAL: child hasn't " | |
1117 | "stopped yet\n"); | |
1118 | } | |
1119 | else if (WIFSTOPPED (status)) | |
1120 | { | |
1121 | if (debug_linux_nat) | |
1122 | fprintf_unfiltered (gdb_stdlog, | |
1123 | "LLAL: adding to stopped_pids\n"); | |
1124 | add_to_pid_list (&stopped_pids, lwpid, status); | |
1125 | } | |
84636d28 PA |
1126 | return 1; |
1127 | } | |
1128 | } | |
1129 | } | |
1130 | ||
9ee57c33 DJ |
1131 | /* If we fail to attach to the thread, issue a warning, |
1132 | but continue. One way this can happen is if thread | |
e9efe249 | 1133 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1134 | bug may place threads in the thread list and then fail |
1135 | to create them. */ | |
1136 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1137 | safe_strerror (errno)); | |
1138 | return -1; | |
1139 | } | |
1140 | ||
d6b0e80f AC |
1141 | if (debug_linux_nat) |
1142 | fprintf_unfiltered (gdb_stdlog, | |
1143 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1144 | target_pid_to_str (ptid)); | |
1145 | ||
a0ef4274 | 1146 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1147 | if (!WIFSTOPPED (status)) |
12696c10 | 1148 | return 1; |
dacc9cb2 | 1149 | |
a0ef4274 DJ |
1150 | lp = add_lwp (ptid); |
1151 | lp->stopped = 1; | |
3b27ef47 | 1152 | lp->last_resume_kind = resume_stop; |
a0ef4274 DJ |
1153 | lp->cloned = cloned; |
1154 | lp->signalled = signalled; | |
1155 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1156 | { |
a0ef4274 DJ |
1157 | lp->resumed = 1; |
1158 | lp->status = status; | |
d6b0e80f AC |
1159 | } |
1160 | ||
dfd4cc63 | 1161 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1162 | |
1163 | if (debug_linux_nat) | |
1164 | { | |
1165 | fprintf_unfiltered (gdb_stdlog, | |
1166 | "LLAL: waitpid %s received %s\n", | |
1167 | target_pid_to_str (ptid), | |
1168 | status_to_str (status)); | |
1169 | } | |
1170 | } | |
9ee57c33 | 1171 | |
9ee57c33 | 1172 | return 0; |
d6b0e80f AC |
1173 | } |
1174 | ||
b84876c2 | 1175 | static void |
136d6dae VP |
1176 | linux_nat_create_inferior (struct target_ops *ops, |
1177 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1178 | int from_tty) |
1179 | { | |
8cc73a39 SDJ |
1180 | struct cleanup *restore_personality |
1181 | = maybe_disable_address_space_randomization (disable_randomization); | |
b84876c2 PA |
1182 | |
1183 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1184 | we have to mask the async mode. */ | |
1185 | ||
2455069d | 1186 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1187 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1188 | |
136d6dae | 1189 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1190 | |
8cc73a39 | 1191 | do_cleanups (restore_personality); |
b84876c2 PA |
1192 | } |
1193 | ||
8784d563 PA |
1194 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not |
1195 | already attached. Returns true if a new LWP is found, false | |
1196 | otherwise. */ | |
1197 | ||
1198 | static int | |
1199 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1200 | { | |
1201 | struct lwp_info *lp; | |
1202 | ||
1203 | /* Ignore LWPs we're already attached to. */ | |
1204 | lp = find_lwp_pid (ptid); | |
1205 | if (lp == NULL) | |
1206 | { | |
1207 | int lwpid = ptid_get_lwp (ptid); | |
1208 | ||
1209 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) | |
1210 | { | |
1211 | int err = errno; | |
1212 | ||
1213 | /* Be quiet if we simply raced with the thread exiting. | |
1214 | EPERM is returned if the thread's task still exists, and | |
1215 | is marked as exited or zombie, as well as other | |
1216 | conditions, so in that case, confirm the status in | |
1217 | /proc/PID/status. */ | |
1218 | if (err == ESRCH | |
1219 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1220 | { | |
1221 | if (debug_linux_nat) | |
1222 | { | |
1223 | fprintf_unfiltered (gdb_stdlog, | |
1224 | "Cannot attach to lwp %d: " | |
1225 | "thread is gone (%d: %s)\n", | |
1226 | lwpid, err, safe_strerror (err)); | |
1227 | } | |
1228 | } | |
1229 | else | |
1230 | { | |
f71f0b0d | 1231 | warning (_("Cannot attach to lwp %d: %s"), |
8784d563 PA |
1232 | lwpid, |
1233 | linux_ptrace_attach_fail_reason_string (ptid, | |
1234 | err)); | |
1235 | } | |
1236 | } | |
1237 | else | |
1238 | { | |
1239 | if (debug_linux_nat) | |
1240 | fprintf_unfiltered (gdb_stdlog, | |
1241 | "PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1242 | target_pid_to_str (ptid)); | |
1243 | ||
1244 | lp = add_lwp (ptid); | |
1245 | lp->cloned = 1; | |
1246 | ||
1247 | /* The next time we wait for this LWP we'll see a SIGSTOP as | |
1248 | PTRACE_ATTACH brings it to a halt. */ | |
1249 | lp->signalled = 1; | |
1250 | ||
1251 | /* We need to wait for a stop before being able to make the | |
1252 | next ptrace call on this LWP. */ | |
1253 | lp->must_set_ptrace_flags = 1; | |
1254 | } | |
1255 | ||
1256 | return 1; | |
1257 | } | |
1258 | return 0; | |
1259 | } | |
1260 | ||
d6b0e80f | 1261 | static void |
c0939df1 | 1262 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1263 | { |
1264 | struct lwp_info *lp; | |
d6b0e80f | 1265 | int status; |
af990527 | 1266 | ptid_t ptid; |
d6b0e80f | 1267 | |
2455069d | 1268 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1269 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1270 | |
492d29ea | 1271 | TRY |
87b0bb13 JK |
1272 | { |
1273 | linux_ops->to_attach (ops, args, from_tty); | |
1274 | } | |
492d29ea | 1275 | CATCH (ex, RETURN_MASK_ERROR) |
87b0bb13 JK |
1276 | { |
1277 | pid_t pid = parse_pid_to_attach (args); | |
1278 | struct buffer buffer; | |
1279 | char *message, *buffer_s; | |
1280 | ||
1281 | message = xstrdup (ex.message); | |
1282 | make_cleanup (xfree, message); | |
1283 | ||
1284 | buffer_init (&buffer); | |
7ae1a6a6 | 1285 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1286 | |
1287 | buffer_grow_str0 (&buffer, ""); | |
1288 | buffer_s = buffer_finish (&buffer); | |
1289 | make_cleanup (xfree, buffer_s); | |
1290 | ||
7ae1a6a6 PA |
1291 | if (*buffer_s != '\0') |
1292 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1293 | else | |
1294 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1295 | } |
492d29ea | 1296 | END_CATCH |
d6b0e80f | 1297 | |
af990527 PA |
1298 | /* The ptrace base target adds the main thread with (pid,0,0) |
1299 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1300 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1301 | ptid_get_pid (inferior_ptid), | |
1302 | 0); | |
af990527 PA |
1303 | thread_change_ptid (inferior_ptid, ptid); |
1304 | ||
9f0bdab8 | 1305 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1306 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1307 | |
1308 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1309 | &lp->signalled); | |
dacc9cb2 PP |
1310 | if (!WIFSTOPPED (status)) |
1311 | { | |
1312 | if (WIFEXITED (status)) | |
1313 | { | |
1314 | int exit_code = WEXITSTATUS (status); | |
1315 | ||
1316 | target_terminal_ours (); | |
1317 | target_mourn_inferior (); | |
1318 | if (exit_code == 0) | |
1319 | error (_("Unable to attach: program exited normally.")); | |
1320 | else | |
1321 | error (_("Unable to attach: program exited with code %d."), | |
1322 | exit_code); | |
1323 | } | |
1324 | else if (WIFSIGNALED (status)) | |
1325 | { | |
2ea28649 | 1326 | enum gdb_signal signo; |
dacc9cb2 PP |
1327 | |
1328 | target_terminal_ours (); | |
1329 | target_mourn_inferior (); | |
1330 | ||
2ea28649 | 1331 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1332 | error (_("Unable to attach: program terminated with signal " |
1333 | "%s, %s."), | |
2ea28649 PA |
1334 | gdb_signal_to_name (signo), |
1335 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1336 | } |
1337 | ||
1338 | internal_error (__FILE__, __LINE__, | |
1339 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1340 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1341 | } |
1342 | ||
a0ef4274 | 1343 | lp->stopped = 1; |
9f0bdab8 | 1344 | |
a0ef4274 | 1345 | /* Save the wait status to report later. */ |
d6b0e80f | 1346 | lp->resumed = 1; |
a0ef4274 DJ |
1347 | if (debug_linux_nat) |
1348 | fprintf_unfiltered (gdb_stdlog, | |
1349 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1350 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1351 | |
7feb7d06 PA |
1352 | lp->status = status; |
1353 | ||
8784d563 PA |
1354 | /* We must attach to every LWP. If /proc is mounted, use that to |
1355 | find them now. The inferior may be using raw clone instead of | |
1356 | using pthreads. But even if it is using pthreads, thread_db | |
1357 | walks structures in the inferior's address space to find the list | |
1358 | of threads/LWPs, and those structures may well be corrupted. | |
1359 | Note that once thread_db is loaded, we'll still use it to list | |
1360 | threads and associate pthread info with each LWP. */ | |
1361 | linux_proc_attach_tgid_threads (ptid_get_pid (lp->ptid), | |
1362 | attach_proc_task_lwp_callback); | |
1363 | ||
7feb7d06 | 1364 | if (target_can_async_p ()) |
6a3753b3 | 1365 | target_async (1); |
d6b0e80f AC |
1366 | } |
1367 | ||
a0ef4274 DJ |
1368 | /* Get pending status of LP. */ |
1369 | static int | |
1370 | get_pending_status (struct lwp_info *lp, int *status) | |
1371 | { | |
a493e3e2 | 1372 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1373 | |
1374 | /* If we paused threads momentarily, we may have stored pending | |
1375 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1376 | and GDB core hasn't seen any signal for those threads. | |
1377 | Otherwise, the last signal reported to the core is found in the | |
1378 | thread object's stop_signal. | |
1379 | ||
1380 | There's a corner case that isn't handled here at present. Only | |
1381 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1382 | stop_signal make sense as a real signal to pass to the inferior. | |
1383 | Some catchpoint related events, like | |
1384 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1385 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1386 | those traps are debug API (ptrace in our case) related and |
1387 | induced; the inferior wouldn't see them if it wasn't being | |
1388 | traced. Hence, we should never pass them to the inferior, even | |
1389 | when set to pass state. Since this corner case isn't handled by | |
1390 | infrun.c when proceeding with a signal, for consistency, neither | |
1391 | do we handle it here (or elsewhere in the file we check for | |
1392 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1393 | this is really a corner case. */ | |
1394 | ||
1395 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1396 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1397 | else if (lp->status) |
2ea28649 | 1398 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1399 | else if (non_stop && !is_executing (lp->ptid)) |
1400 | { | |
1401 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1402 | |
16c381f0 | 1403 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1404 | } |
1405 | else if (!non_stop) | |
a0ef4274 | 1406 | { |
ca2163eb PA |
1407 | struct target_waitstatus last; |
1408 | ptid_t last_ptid; | |
4c28f408 | 1409 | |
ca2163eb | 1410 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1411 | |
dfd4cc63 | 1412 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1413 | { |
e09875d4 | 1414 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1415 | |
16c381f0 | 1416 | signo = tp->suspend.stop_signal; |
4c28f408 | 1417 | } |
ca2163eb | 1418 | } |
4c28f408 | 1419 | |
ca2163eb | 1420 | *status = 0; |
4c28f408 | 1421 | |
a493e3e2 | 1422 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1423 | { |
1424 | if (debug_linux_nat) | |
1425 | fprintf_unfiltered (gdb_stdlog, | |
1426 | "GPT: lwp %s has no pending signal\n", | |
1427 | target_pid_to_str (lp->ptid)); | |
1428 | } | |
1429 | else if (!signal_pass_state (signo)) | |
1430 | { | |
1431 | if (debug_linux_nat) | |
3e43a32a MS |
1432 | fprintf_unfiltered (gdb_stdlog, |
1433 | "GPT: lwp %s had signal %s, " | |
1434 | "but it is in no pass state\n", | |
ca2163eb | 1435 | target_pid_to_str (lp->ptid), |
2ea28649 | 1436 | gdb_signal_to_string (signo)); |
a0ef4274 | 1437 | } |
a0ef4274 | 1438 | else |
4c28f408 | 1439 | { |
2ea28649 | 1440 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1441 | |
1442 | if (debug_linux_nat) | |
1443 | fprintf_unfiltered (gdb_stdlog, | |
1444 | "GPT: lwp %s has pending signal %s\n", | |
1445 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1446 | gdb_signal_to_string (signo)); |
4c28f408 | 1447 | } |
a0ef4274 DJ |
1448 | |
1449 | return 0; | |
1450 | } | |
1451 | ||
d6b0e80f AC |
1452 | static int |
1453 | detach_callback (struct lwp_info *lp, void *data) | |
1454 | { | |
1455 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1456 | ||
1457 | if (debug_linux_nat && lp->status) | |
1458 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1459 | strsignal (WSTOPSIG (lp->status)), | |
1460 | target_pid_to_str (lp->ptid)); | |
1461 | ||
a0ef4274 DJ |
1462 | /* If there is a pending SIGSTOP, get rid of it. */ |
1463 | if (lp->signalled) | |
d6b0e80f | 1464 | { |
d6b0e80f AC |
1465 | if (debug_linux_nat) |
1466 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1467 | "DC: Sending SIGCONT to %s\n", |
1468 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1469 | |
dfd4cc63 | 1470 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1471 | lp->signalled = 0; |
d6b0e80f AC |
1472 | } |
1473 | ||
1474 | /* We don't actually detach from the LWP that has an id equal to the | |
1475 | overall process id just yet. */ | |
dfd4cc63 | 1476 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1477 | { |
a0ef4274 DJ |
1478 | int status = 0; |
1479 | ||
1480 | /* Pass on any pending signal for this LWP. */ | |
1481 | get_pending_status (lp, &status); | |
1482 | ||
7b50312a PA |
1483 | if (linux_nat_prepare_to_resume != NULL) |
1484 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1485 | errno = 0; |
dfd4cc63 | 1486 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1487 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1488 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1489 | safe_strerror (errno)); |
1490 | ||
1491 | if (debug_linux_nat) | |
1492 | fprintf_unfiltered (gdb_stdlog, | |
1493 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1494 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1495 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1496 | |
1497 | delete_lwp (lp->ptid); | |
1498 | } | |
1499 | ||
1500 | return 0; | |
1501 | } | |
1502 | ||
1503 | static void | |
52554a0e | 1504 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1505 | { |
b84876c2 | 1506 | int pid; |
a0ef4274 | 1507 | int status; |
d90e17a7 PA |
1508 | struct lwp_info *main_lwp; |
1509 | ||
dfd4cc63 | 1510 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1511 | |
ae5e0686 MK |
1512 | /* Don't unregister from the event loop, as there may be other |
1513 | inferiors running. */ | |
b84876c2 | 1514 | |
4c28f408 PA |
1515 | /* Stop all threads before detaching. ptrace requires that the |
1516 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1517 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1518 | /* ... and wait until all of them have reported back that |
1519 | they're no longer running. */ | |
d90e17a7 | 1520 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1521 | |
d90e17a7 | 1522 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1523 | |
1524 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1525 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1526 | |
1527 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1528 | |
a0ef4274 DJ |
1529 | /* Pass on any pending signal for the last LWP. */ |
1530 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1531 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1532 | && WIFSTOPPED (status)) |
1533 | { | |
52554a0e TT |
1534 | char *tem; |
1535 | ||
a0ef4274 DJ |
1536 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1537 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1538 | tem = alloca (8); |
cde33bf1 | 1539 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1540 | args = tem; |
ddabfc73 TT |
1541 | if (debug_linux_nat) |
1542 | fprintf_unfiltered (gdb_stdlog, | |
1543 | "LND: Sending signal %s to %s\n", | |
1544 | args, | |
1545 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1546 | } |
1547 | ||
7b50312a PA |
1548 | if (linux_nat_prepare_to_resume != NULL) |
1549 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1550 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1551 | |
7a7d3353 PA |
1552 | if (forks_exist_p ()) |
1553 | { | |
1554 | /* Multi-fork case. The current inferior_ptid is being detached | |
1555 | from, but there are other viable forks to debug. Detach from | |
1556 | the current fork, and context-switch to the first | |
1557 | available. */ | |
1558 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1559 | } |
1560 | else | |
1561 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1562 | } |
1563 | ||
8a99810d PA |
1564 | /* Resume execution of the inferior process. If STEP is nonzero, |
1565 | single-step it. If SIGNAL is nonzero, give it that signal. */ | |
1566 | ||
1567 | static void | |
23f238d3 PA |
1568 | linux_resume_one_lwp_throw (struct lwp_info *lp, int step, |
1569 | enum gdb_signal signo) | |
8a99810d | 1570 | { |
8a99810d | 1571 | lp->step = step; |
9c02b525 PA |
1572 | |
1573 | /* stop_pc doubles as the PC the LWP had when it was last resumed. | |
1574 | We only presently need that if the LWP is stepped though (to | |
1575 | handle the case of stepping a breakpoint instruction). */ | |
1576 | if (step) | |
1577 | { | |
1578 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
1579 | ||
1580 | lp->stop_pc = regcache_read_pc (regcache); | |
1581 | } | |
1582 | else | |
1583 | lp->stop_pc = 0; | |
1584 | ||
8a99810d PA |
1585 | if (linux_nat_prepare_to_resume != NULL) |
1586 | linux_nat_prepare_to_resume (lp); | |
90ad5e1d | 1587 | linux_ops->to_resume (linux_ops, lp->ptid, step, signo); |
23f238d3 PA |
1588 | |
1589 | /* Successfully resumed. Clear state that no longer makes sense, | |
1590 | and mark the LWP as running. Must not do this before resuming | |
1591 | otherwise if that fails other code will be confused. E.g., we'd | |
1592 | later try to stop the LWP and hang forever waiting for a stop | |
1593 | status. Note that we must not throw after this is cleared, | |
1594 | otherwise handle_zombie_lwp_error would get confused. */ | |
8a99810d | 1595 | lp->stopped = 0; |
23f238d3 | 1596 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; |
8a99810d PA |
1597 | registers_changed_ptid (lp->ptid); |
1598 | } | |
1599 | ||
23f238d3 PA |
1600 | /* Called when we try to resume a stopped LWP and that errors out. If |
1601 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
1602 | or about to become), discard the error, clear any pending status | |
1603 | the LWP may have, and return true (we'll collect the exit status | |
1604 | soon enough). Otherwise, return false. */ | |
1605 | ||
1606 | static int | |
1607 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
1608 | { | |
1609 | /* If we get an error after resuming the LWP successfully, we'd | |
1610 | confuse !T state for the LWP being gone. */ | |
1611 | gdb_assert (lp->stopped); | |
1612 | ||
1613 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
1614 | because even if ptrace failed with ESRCH, the tracee may be "not | |
1615 | yet fully dead", but already refusing ptrace requests. In that | |
1616 | case the tracee has 'R (Running)' state for a little bit | |
1617 | (observed in Linux 3.18). See also the note on ESRCH in the | |
1618 | ptrace(2) man page. Instead, check whether the LWP has any state | |
1619 | other than ptrace-stopped. */ | |
1620 | ||
1621 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
1622 | if (linux_proc_pid_is_trace_stopped_nowarn (ptid_get_lwp (lp->ptid)) == 0) | |
1623 | { | |
1624 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
1625 | lp->status = 0; | |
1626 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
1627 | return 1; | |
1628 | } | |
1629 | return 0; | |
1630 | } | |
1631 | ||
1632 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
1633 | disappears while we try to resume it. */ | |
1634 | ||
1635 | static void | |
1636 | linux_resume_one_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) | |
1637 | { | |
1638 | TRY | |
1639 | { | |
1640 | linux_resume_one_lwp_throw (lp, step, signo); | |
1641 | } | |
1642 | CATCH (ex, RETURN_MASK_ERROR) | |
1643 | { | |
1644 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
1645 | throw_exception (ex); | |
1646 | } | |
1647 | END_CATCH | |
1648 | } | |
1649 | ||
d6b0e80f AC |
1650 | /* Resume LP. */ |
1651 | ||
25289eb2 | 1652 | static void |
e5ef252a | 1653 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1654 | { |
25289eb2 | 1655 | if (lp->stopped) |
6c95b8df | 1656 | { |
c9657e70 | 1657 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
25289eb2 PA |
1658 | |
1659 | if (inf->vfork_child != NULL) | |
1660 | { | |
1661 | if (debug_linux_nat) | |
1662 | fprintf_unfiltered (gdb_stdlog, | |
1663 | "RC: Not resuming %s (vfork parent)\n", | |
1664 | target_pid_to_str (lp->ptid)); | |
1665 | } | |
8a99810d | 1666 | else if (!lwp_status_pending_p (lp)) |
25289eb2 PA |
1667 | { |
1668 | if (debug_linux_nat) | |
1669 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1670 | "RC: Resuming sibling %s, %s, %s\n", |
1671 | target_pid_to_str (lp->ptid), | |
1672 | (signo != GDB_SIGNAL_0 | |
1673 | ? strsignal (gdb_signal_to_host (signo)) | |
1674 | : "0"), | |
1675 | step ? "step" : "resume"); | |
25289eb2 | 1676 | |
8a99810d | 1677 | linux_resume_one_lwp (lp, step, signo); |
25289eb2 PA |
1678 | } |
1679 | else | |
1680 | { | |
1681 | if (debug_linux_nat) | |
1682 | fprintf_unfiltered (gdb_stdlog, | |
1683 | "RC: Not resuming sibling %s (has pending)\n", | |
1684 | target_pid_to_str (lp->ptid)); | |
1685 | } | |
6c95b8df | 1686 | } |
25289eb2 | 1687 | else |
d6b0e80f | 1688 | { |
d90e17a7 PA |
1689 | if (debug_linux_nat) |
1690 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1691 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1692 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1693 | } |
25289eb2 | 1694 | } |
d6b0e80f | 1695 | |
8817a6f2 PA |
1696 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1697 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1698 | |
25289eb2 | 1699 | static int |
8817a6f2 | 1700 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1701 | { |
e5ef252a PA |
1702 | enum gdb_signal signo = GDB_SIGNAL_0; |
1703 | ||
8817a6f2 PA |
1704 | if (lp == except) |
1705 | return 0; | |
1706 | ||
e5ef252a PA |
1707 | if (lp->stopped) |
1708 | { | |
1709 | struct thread_info *thread; | |
1710 | ||
1711 | thread = find_thread_ptid (lp->ptid); | |
1712 | if (thread != NULL) | |
1713 | { | |
70509625 | 1714 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1715 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1716 | } | |
1717 | } | |
1718 | ||
1719 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1720 | return 0; |
1721 | } | |
1722 | ||
1723 | static int | |
1724 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1725 | { | |
1726 | lp->resumed = 0; | |
25289eb2 | 1727 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1728 | return 0; |
1729 | } | |
1730 | ||
1731 | static int | |
1732 | resume_set_callback (struct lwp_info *lp, void *data) | |
1733 | { | |
1734 | lp->resumed = 1; | |
25289eb2 | 1735 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1736 | return 0; |
1737 | } | |
1738 | ||
1739 | static void | |
28439f5e | 1740 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1741 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1742 | { |
1743 | struct lwp_info *lp; | |
d90e17a7 | 1744 | int resume_many; |
d6b0e80f | 1745 | |
76f50ad1 DJ |
1746 | if (debug_linux_nat) |
1747 | fprintf_unfiltered (gdb_stdlog, | |
1748 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1749 | step ? "step" : "resume", | |
1750 | target_pid_to_str (ptid), | |
a493e3e2 | 1751 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1752 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1753 | target_pid_to_str (inferior_ptid)); |
1754 | ||
d6b0e80f | 1755 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1756 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1757 | || ptid_is_pid (ptid)); | |
4c28f408 | 1758 | |
e3e9f5a2 PA |
1759 | /* Mark the lwps we're resuming as resumed. */ |
1760 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1761 | |
d90e17a7 PA |
1762 | /* See if it's the current inferior that should be handled |
1763 | specially. */ | |
1764 | if (resume_many) | |
1765 | lp = find_lwp_pid (inferior_ptid); | |
1766 | else | |
1767 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1768 | gdb_assert (lp != NULL); |
d6b0e80f | 1769 | |
9f0bdab8 | 1770 | /* Remember if we're stepping. */ |
25289eb2 | 1771 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1772 | |
9f0bdab8 DJ |
1773 | /* If we have a pending wait status for this thread, there is no |
1774 | point in resuming the process. But first make sure that | |
1775 | linux_nat_wait won't preemptively handle the event - we | |
1776 | should never take this short-circuit if we are going to | |
1777 | leave LP running, since we have skipped resuming all the | |
1778 | other threads. This bit of code needs to be synchronized | |
1779 | with linux_nat_wait. */ | |
76f50ad1 | 1780 | |
9f0bdab8 DJ |
1781 | if (lp->status && WIFSTOPPED (lp->status)) |
1782 | { | |
2455069d UW |
1783 | if (!lp->step |
1784 | && WSTOPSIG (lp->status) | |
1785 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1786 | { |
9f0bdab8 DJ |
1787 | if (debug_linux_nat) |
1788 | fprintf_unfiltered (gdb_stdlog, | |
1789 | "LLR: Not short circuiting for ignored " | |
1790 | "status 0x%x\n", lp->status); | |
1791 | ||
d6b0e80f AC |
1792 | /* FIXME: What should we do if we are supposed to continue |
1793 | this thread with a signal? */ | |
a493e3e2 | 1794 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1795 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1796 | lp->status = 0; |
1797 | } | |
1798 | } | |
76f50ad1 | 1799 | |
8a99810d | 1800 | if (lwp_status_pending_p (lp)) |
9f0bdab8 DJ |
1801 | { |
1802 | /* FIXME: What should we do if we are supposed to continue | |
1803 | this thread with a signal? */ | |
a493e3e2 | 1804 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1805 | |
9f0bdab8 DJ |
1806 | if (debug_linux_nat) |
1807 | fprintf_unfiltered (gdb_stdlog, | |
1808 | "LLR: Short circuiting for status 0x%x\n", | |
1809 | lp->status); | |
d6b0e80f | 1810 | |
7feb7d06 PA |
1811 | if (target_can_async_p ()) |
1812 | { | |
6a3753b3 | 1813 | target_async (1); |
7feb7d06 PA |
1814 | /* Tell the event loop we have something to process. */ |
1815 | async_file_mark (); | |
1816 | } | |
9f0bdab8 | 1817 | return; |
d6b0e80f AC |
1818 | } |
1819 | ||
d90e17a7 | 1820 | if (resume_many) |
8817a6f2 | 1821 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 | 1822 | |
d6b0e80f AC |
1823 | if (debug_linux_nat) |
1824 | fprintf_unfiltered (gdb_stdlog, | |
1825 | "LLR: %s %s, %s (resume event thread)\n", | |
1826 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2bf6fb9d | 1827 | target_pid_to_str (lp->ptid), |
a493e3e2 | 1828 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1829 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 | 1830 | |
2bf6fb9d PA |
1831 | linux_resume_one_lwp (lp, step, signo); |
1832 | ||
b84876c2 | 1833 | if (target_can_async_p ()) |
6a3753b3 | 1834 | target_async (1); |
d6b0e80f AC |
1835 | } |
1836 | ||
c5f62d5f | 1837 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1838 | |
1839 | static int | |
1840 | kill_lwp (int lwpid, int signo) | |
1841 | { | |
c5f62d5f DE |
1842 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1843 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1844 | |
1845 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1846 | { |
1847 | static int tkill_failed; | |
1848 | ||
1849 | if (!tkill_failed) | |
1850 | { | |
1851 | int ret; | |
1852 | ||
1853 | errno = 0; | |
1854 | ret = syscall (__NR_tkill, lwpid, signo); | |
1855 | if (errno != ENOSYS) | |
1856 | return ret; | |
1857 | tkill_failed = 1; | |
1858 | } | |
1859 | } | |
d6b0e80f AC |
1860 | #endif |
1861 | ||
1862 | return kill (lwpid, signo); | |
1863 | } | |
1864 | ||
ca2163eb PA |
1865 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1866 | event, check if the core is interested in it: if not, ignore the | |
1867 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1868 | syscall entry/exit status, since the ptrace event itself doesn't | |
1869 | indicate it, and report the trap to higher layers. */ | |
1870 | ||
1871 | static int | |
1872 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1873 | { | |
1874 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1875 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1876 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1877 | ||
1878 | if (stopping) | |
1879 | { | |
1880 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1881 | makes it so that the LWP reports an immediate syscall return, | |
1882 | followed by the SIGSTOP. Skip seeing that "return" using | |
1883 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1884 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1885 | entry event. If we didn't do this (and returned 0), we'd | |
1886 | leave a syscall entry pending, and our caller, by using | |
1887 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1888 | itself. Later, when the user re-resumes this LWP, we'd see | |
1889 | another syscall entry event and we'd mistake it for a return. | |
1890 | ||
1891 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1892 | (leaving immediately with LWP->signalled set, without issuing | |
1893 | a PTRACE_CONT), it would still be problematic to leave this | |
1894 | syscall enter pending, as later when the thread is resumed, | |
1895 | it would then see the same syscall exit mentioned above, | |
1896 | followed by the delayed SIGSTOP, while the syscall didn't | |
1897 | actually get to execute. It seems it would be even more | |
1898 | confusing to the user. */ | |
1899 | ||
1900 | if (debug_linux_nat) | |
1901 | fprintf_unfiltered (gdb_stdlog, | |
1902 | "LHST: ignoring syscall %d " | |
1903 | "for LWP %ld (stopping threads), " | |
1904 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1905 | syscall_number, | |
dfd4cc63 | 1906 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1907 | |
1908 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1909 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1910 | lp->stopped = 0; |
ca2163eb PA |
1911 | return 1; |
1912 | } | |
1913 | ||
1914 | if (catch_syscall_enabled ()) | |
1915 | { | |
1916 | /* Always update the entry/return state, even if this particular | |
1917 | syscall isn't interesting to the core now. In async mode, | |
1918 | the user could install a new catchpoint for this syscall | |
1919 | between syscall enter/return, and we'll need to know to | |
1920 | report a syscall return if that happens. */ | |
1921 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1922 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1923 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1924 | ||
1925 | if (catching_syscall_number (syscall_number)) | |
1926 | { | |
1927 | /* Alright, an event to report. */ | |
1928 | ourstatus->kind = lp->syscall_state; | |
1929 | ourstatus->value.syscall_number = syscall_number; | |
1930 | ||
1931 | if (debug_linux_nat) | |
1932 | fprintf_unfiltered (gdb_stdlog, | |
1933 | "LHST: stopping for %s of syscall %d" | |
1934 | " for LWP %ld\n", | |
3e43a32a MS |
1935 | lp->syscall_state |
1936 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1937 | ? "entry" : "return", |
1938 | syscall_number, | |
dfd4cc63 | 1939 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1940 | return 0; |
1941 | } | |
1942 | ||
1943 | if (debug_linux_nat) | |
1944 | fprintf_unfiltered (gdb_stdlog, | |
1945 | "LHST: ignoring %s of syscall %d " | |
1946 | "for LWP %ld\n", | |
1947 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1948 | ? "entry" : "return", | |
1949 | syscall_number, | |
dfd4cc63 | 1950 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1951 | } |
1952 | else | |
1953 | { | |
1954 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1955 | before on this LWP, it could happen that the user removes all | |
1956 | syscall catchpoints before we get to process this event. | |
1957 | There are two noteworthy issues here: | |
1958 | ||
1959 | - When stopped at a syscall entry event, resuming with | |
1960 | PT_STEP still resumes executing the syscall and reports a | |
1961 | syscall return. | |
1962 | ||
1963 | - Only PT_SYSCALL catches syscall enters. If we last | |
1964 | single-stepped this thread, then this event can't be a | |
1965 | syscall enter. If we last single-stepped this thread, this | |
1966 | has to be a syscall exit. | |
1967 | ||
1968 | The points above mean that the next resume, be it PT_STEP or | |
1969 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1970 | if (debug_linux_nat) | |
1971 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1972 | "LHST: caught syscall event " |
1973 | "with no syscall catchpoints." | |
ca2163eb PA |
1974 | " %d for LWP %ld, ignoring\n", |
1975 | syscall_number, | |
dfd4cc63 | 1976 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1977 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1978 | } | |
1979 | ||
1980 | /* The core isn't interested in this event. For efficiency, avoid | |
1981 | stopping all threads only to have the core resume them all again. | |
1982 | Since we're not stopping threads, if we're still syscall tracing | |
1983 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1984 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1985 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1986 | ||
8a99810d | 1987 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1988 | return 1; |
1989 | } | |
1990 | ||
3d799a95 DJ |
1991 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1992 | event, we need to add the new LWP to our list (and not report the | |
1993 | trap to higher layers). This function returns non-zero if the | |
1994 | event should be ignored and we should wait again. If STOPPING is | |
1995 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1996 | |
1997 | static int | |
3d799a95 DJ |
1998 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1999 | int stopping) | |
d6b0e80f | 2000 | { |
dfd4cc63 | 2001 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 2002 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
89a5711c | 2003 | int event = linux_ptrace_get_extended_event (status); |
d6b0e80f | 2004 | |
3d799a95 DJ |
2005 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
2006 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 2007 | { |
3d799a95 DJ |
2008 | unsigned long new_pid; |
2009 | int ret; | |
2010 | ||
2011 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 2012 | |
3d799a95 DJ |
2013 | /* If we haven't already seen the new PID stop, wait for it now. */ |
2014 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2015 | { | |
2016 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2017 | hits the SIGSTOP, but we're already attached. */ | |
2018 | ret = my_waitpid (new_pid, &status, | |
2019 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2020 | if (ret == -1) | |
2021 | perror_with_name (_("waiting for new child")); | |
2022 | else if (ret != new_pid) | |
2023 | internal_error (__FILE__, __LINE__, | |
2024 | _("wait returned unexpected PID %d"), ret); | |
2025 | else if (!WIFSTOPPED (status)) | |
2026 | internal_error (__FILE__, __LINE__, | |
2027 | _("wait returned unexpected status 0x%x"), status); | |
2028 | } | |
2029 | ||
3a3e9ee3 | 2030 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2031 | |
26cb8b7c PA |
2032 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2033 | { | |
2034 | /* The arch-specific native code may need to know about new | |
2035 | forks even if those end up never mapped to an | |
2036 | inferior. */ | |
2037 | if (linux_nat_new_fork != NULL) | |
2038 | linux_nat_new_fork (lp, new_pid); | |
2039 | } | |
2040 | ||
2277426b | 2041 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2042 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2043 | { |
2277426b PA |
2044 | /* Handle checkpointing by linux-fork.c here as a special |
2045 | case. We don't want the follow-fork-mode or 'catch fork' | |
2046 | to interfere with this. */ | |
2047 | ||
2048 | /* This won't actually modify the breakpoint list, but will | |
2049 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2050 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2051 | |
2052 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2053 | if (!find_fork_pid (new_pid)) |
2054 | add_fork (new_pid); | |
2277426b PA |
2055 | |
2056 | /* Report as spurious, so that infrun doesn't want to follow | |
2057 | this fork. We're actually doing an infcall in | |
2058 | linux-fork.c. */ | |
2059 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2060 | |
2061 | /* Report the stop to the core. */ | |
2062 | return 0; | |
2063 | } | |
2064 | ||
3d799a95 DJ |
2065 | if (event == PTRACE_EVENT_FORK) |
2066 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2067 | else if (event == PTRACE_EVENT_VFORK) | |
2068 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2069 | else |
3d799a95 | 2070 | { |
78768c4a JK |
2071 | struct lwp_info *new_lp; |
2072 | ||
3d799a95 | 2073 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2074 | |
3c4d7e12 PA |
2075 | if (debug_linux_nat) |
2076 | fprintf_unfiltered (gdb_stdlog, | |
2077 | "LHEW: Got clone event " | |
2078 | "from LWP %d, new child is LWP %ld\n", | |
2079 | pid, new_pid); | |
2080 | ||
dfd4cc63 | 2081 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2082 | new_lp->cloned = 1; |
4c28f408 | 2083 | new_lp->stopped = 1; |
d6b0e80f | 2084 | |
3d799a95 DJ |
2085 | if (WSTOPSIG (status) != SIGSTOP) |
2086 | { | |
2087 | /* This can happen if someone starts sending signals to | |
2088 | the new thread before it gets a chance to run, which | |
2089 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2090 | This is an unlikely case, and harder to handle for | |
2091 | fork / vfork than for clone, so we do not try - but | |
2092 | we handle it for clone events here. We'll send | |
2093 | the other signal on to the thread below. */ | |
2094 | ||
2095 | new_lp->signalled = 1; | |
2096 | } | |
2097 | else | |
79395f92 PA |
2098 | { |
2099 | struct thread_info *tp; | |
2100 | ||
2101 | /* When we stop for an event in some other thread, and | |
2102 | pull the thread list just as this thread has cloned, | |
2103 | we'll have seen the new thread in the thread_db list | |
2104 | before handling the CLONE event (glibc's | |
2105 | pthread_create adds the new thread to the thread list | |
2106 | before clone'ing, and has the kernel fill in the | |
2107 | thread's tid on the clone call with | |
2108 | CLONE_PARENT_SETTID). If that happened, and the core | |
2109 | had requested the new thread to stop, we'll have | |
2110 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2111 | RT signal, it can only be queued once. We need to be | |
2112 | careful to not resume the LWP if we wanted it to | |
2113 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2114 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2115 | tp = find_thread_ptid (new_lp->ptid); |
2116 | if (tp != NULL && tp->stop_requested) | |
2117 | new_lp->last_resume_kind = resume_stop; | |
2118 | else | |
2119 | status = 0; | |
2120 | } | |
d6b0e80f | 2121 | |
2db9a427 PA |
2122 | /* If the thread_db layer is active, let it record the user |
2123 | level thread id and status, and add the thread to GDB's | |
2124 | list. */ | |
2125 | if (!thread_db_notice_clone (lp->ptid, new_lp->ptid)) | |
3d799a95 | 2126 | { |
2db9a427 PA |
2127 | /* The process is not using thread_db. Add the LWP to |
2128 | GDB's list. */ | |
2129 | target_post_attach (ptid_get_lwp (new_lp->ptid)); | |
2130 | add_thread (new_lp->ptid); | |
2131 | } | |
4c28f408 | 2132 | |
2ee52aa4 PA |
2133 | /* Even if we're stopping the thread for some reason |
2134 | internal to this module, from the user/frontend's | |
2135 | perspective, this new thread is running. */ | |
2136 | set_running (new_lp->ptid, 1); | |
2db9a427 PA |
2137 | if (!stopping) |
2138 | { | |
2db9a427 PA |
2139 | set_executing (new_lp->ptid, 1); |
2140 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced | |
2141 | resume_stop. */ | |
2142 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2143 | } |
2144 | ||
79395f92 PA |
2145 | if (status != 0) |
2146 | { | |
2147 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2148 | gdb_assert (new_lp->status == 0); | |
2149 | ||
2150 | /* Save the wait status to report later. */ | |
2151 | if (debug_linux_nat) | |
2152 | fprintf_unfiltered (gdb_stdlog, | |
2153 | "LHEW: waitpid of new LWP %ld, " | |
2154 | "saving status %s\n", | |
dfd4cc63 | 2155 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2156 | status_to_str (status)); |
2157 | new_lp->status = status; | |
2158 | } | |
2159 | ||
20ba1ce6 | 2160 | new_lp->resumed = !stopping; |
3d799a95 DJ |
2161 | return 1; |
2162 | } | |
2163 | ||
2164 | return 0; | |
d6b0e80f AC |
2165 | } |
2166 | ||
3d799a95 DJ |
2167 | if (event == PTRACE_EVENT_EXEC) |
2168 | { | |
a75724bc PA |
2169 | if (debug_linux_nat) |
2170 | fprintf_unfiltered (gdb_stdlog, | |
2171 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2172 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2173 | |
3d799a95 DJ |
2174 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2175 | ourstatus->value.execd_pathname | |
8dd27370 | 2176 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2177 | |
8af756ef PA |
2178 | /* The thread that execed must have been resumed, but, when a |
2179 | thread execs, it changes its tid to the tgid, and the old | |
2180 | tgid thread might have not been resumed. */ | |
2181 | lp->resumed = 1; | |
6c95b8df PA |
2182 | return 0; |
2183 | } | |
2184 | ||
2185 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2186 | { | |
2187 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2188 | { |
6c95b8df | 2189 | if (debug_linux_nat) |
3e43a32a MS |
2190 | fprintf_unfiltered (gdb_stdlog, |
2191 | "LHEW: Got expected PTRACE_EVENT_" | |
2192 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2193 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2194 | |
6c95b8df PA |
2195 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2196 | return 0; | |
3d799a95 DJ |
2197 | } |
2198 | ||
6c95b8df | 2199 | if (debug_linux_nat) |
3e43a32a MS |
2200 | fprintf_unfiltered (gdb_stdlog, |
2201 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
20ba1ce6 | 2202 | "from LWP %ld: ignoring\n", |
dfd4cc63 | 2203 | ptid_get_lwp (lp->ptid)); |
6c95b8df | 2204 | return 1; |
3d799a95 DJ |
2205 | } |
2206 | ||
2207 | internal_error (__FILE__, __LINE__, | |
2208 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2209 | } |
2210 | ||
2211 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2212 | exited. */ | |
2213 | ||
2214 | static int | |
2215 | wait_lwp (struct lwp_info *lp) | |
2216 | { | |
2217 | pid_t pid; | |
432b4d03 | 2218 | int status = 0; |
d6b0e80f | 2219 | int thread_dead = 0; |
432b4d03 | 2220 | sigset_t prev_mask; |
d6b0e80f AC |
2221 | |
2222 | gdb_assert (!lp->stopped); | |
2223 | gdb_assert (lp->status == 0); | |
2224 | ||
432b4d03 JK |
2225 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2226 | block_child_signals (&prev_mask); | |
2227 | ||
2228 | for (;;) | |
d6b0e80f | 2229 | { |
432b4d03 JK |
2230 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2231 | was right and we should just call sigsuspend. */ | |
2232 | ||
dfd4cc63 | 2233 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2234 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2235 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2236 | if (pid == -1 && errno == ECHILD) |
2237 | { | |
2238 | /* The thread has previously exited. We need to delete it | |
2239 | now because, for some vendor 2.4 kernels with NPTL | |
2240 | support backported, there won't be an exit event unless | |
2241 | it is the main thread. 2.6 kernels will report an exit | |
2242 | event for each thread that exits, as expected. */ | |
2243 | thread_dead = 1; | |
2244 | if (debug_linux_nat) | |
2245 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2246 | target_pid_to_str (lp->ptid)); | |
2247 | } | |
432b4d03 JK |
2248 | if (pid != 0) |
2249 | break; | |
2250 | ||
2251 | /* Bugs 10970, 12702. | |
2252 | Thread group leader may have exited in which case we'll lock up in | |
2253 | waitpid if there are other threads, even if they are all zombies too. | |
2254 | Basically, we're not supposed to use waitpid this way. | |
2255 | __WCLONE is not applicable for the leader so we can't use that. | |
2256 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2257 | process; it gets ESRCH both for the zombie and for running processes. | |
2258 | ||
2259 | As a workaround, check if we're waiting for the thread group leader and | |
2260 | if it's a zombie, and avoid calling waitpid if it is. | |
2261 | ||
2262 | This is racy, what if the tgl becomes a zombie right after we check? | |
2263 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2264 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2265 | |
dfd4cc63 LM |
2266 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2267 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2268 | { |
d6b0e80f AC |
2269 | thread_dead = 1; |
2270 | if (debug_linux_nat) | |
432b4d03 JK |
2271 | fprintf_unfiltered (gdb_stdlog, |
2272 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2273 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2274 | break; |
d6b0e80f | 2275 | } |
432b4d03 JK |
2276 | |
2277 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2278 | get invoked despite our caller had them intentionally blocked by | |
2279 | block_child_signals. This is sensitive only to the loop of | |
2280 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2281 | again before it gets to sigsuspend so we can safely let the handlers | |
2282 | get executed here. */ | |
2283 | ||
d36bf488 DE |
2284 | if (debug_linux_nat) |
2285 | fprintf_unfiltered (gdb_stdlog, "WL: about to sigsuspend\n"); | |
432b4d03 JK |
2286 | sigsuspend (&suspend_mask); |
2287 | } | |
2288 | ||
2289 | restore_child_signals_mask (&prev_mask); | |
2290 | ||
d6b0e80f AC |
2291 | if (!thread_dead) |
2292 | { | |
dfd4cc63 | 2293 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2294 | |
2295 | if (debug_linux_nat) | |
2296 | { | |
2297 | fprintf_unfiltered (gdb_stdlog, | |
2298 | "WL: waitpid %s received %s\n", | |
2299 | target_pid_to_str (lp->ptid), | |
2300 | status_to_str (status)); | |
2301 | } | |
d6b0e80f | 2302 | |
a9f4bb21 PA |
2303 | /* Check if the thread has exited. */ |
2304 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2305 | { | |
2306 | thread_dead = 1; | |
2307 | if (debug_linux_nat) | |
2308 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2309 | target_pid_to_str (lp->ptid)); | |
2310 | } | |
d6b0e80f AC |
2311 | } |
2312 | ||
2313 | if (thread_dead) | |
2314 | { | |
e26af52f | 2315 | exit_lwp (lp); |
d6b0e80f AC |
2316 | return 0; |
2317 | } | |
2318 | ||
2319 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2320 | lp->stopped = 1; |
d6b0e80f | 2321 | |
8784d563 PA |
2322 | if (lp->must_set_ptrace_flags) |
2323 | { | |
2324 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
de0d863e | 2325 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2326 | |
de0d863e | 2327 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), options); |
8784d563 PA |
2328 | lp->must_set_ptrace_flags = 0; |
2329 | } | |
2330 | ||
ca2163eb PA |
2331 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2332 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2333 | { | |
2334 | /* No longer need the sysgood bit. The ptrace event ends up | |
2335 | recorded in lp->waitstatus if we care for it. We can carry | |
2336 | on handling the event like a regular SIGTRAP from here | |
2337 | on. */ | |
2338 | status = W_STOPCODE (SIGTRAP); | |
2339 | if (linux_handle_syscall_trap (lp, 1)) | |
2340 | return wait_lwp (lp); | |
2341 | } | |
2342 | ||
d6b0e80f | 2343 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
2344 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
2345 | && linux_is_extended_waitstatus (status)) | |
d6b0e80f AC |
2346 | { |
2347 | if (debug_linux_nat) | |
2348 | fprintf_unfiltered (gdb_stdlog, | |
2349 | "WL: Handling extended status 0x%06x\n", | |
2350 | status); | |
20ba1ce6 PA |
2351 | linux_handle_extended_wait (lp, status, 1); |
2352 | return 0; | |
d6b0e80f AC |
2353 | } |
2354 | ||
2355 | return status; | |
2356 | } | |
2357 | ||
2358 | /* Send a SIGSTOP to LP. */ | |
2359 | ||
2360 | static int | |
2361 | stop_callback (struct lwp_info *lp, void *data) | |
2362 | { | |
2363 | if (!lp->stopped && !lp->signalled) | |
2364 | { | |
2365 | int ret; | |
2366 | ||
2367 | if (debug_linux_nat) | |
2368 | { | |
2369 | fprintf_unfiltered (gdb_stdlog, | |
2370 | "SC: kill %s **<SIGSTOP>**\n", | |
2371 | target_pid_to_str (lp->ptid)); | |
2372 | } | |
2373 | errno = 0; | |
dfd4cc63 | 2374 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2375 | if (debug_linux_nat) |
2376 | { | |
2377 | fprintf_unfiltered (gdb_stdlog, | |
2378 | "SC: lwp kill %d %s\n", | |
2379 | ret, | |
2380 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2381 | } | |
2382 | ||
2383 | lp->signalled = 1; | |
2384 | gdb_assert (lp->status == 0); | |
2385 | } | |
2386 | ||
2387 | return 0; | |
2388 | } | |
2389 | ||
7b50312a PA |
2390 | /* Request a stop on LWP. */ |
2391 | ||
2392 | void | |
2393 | linux_stop_lwp (struct lwp_info *lwp) | |
2394 | { | |
2395 | stop_callback (lwp, NULL); | |
2396 | } | |
2397 | ||
2db9a427 PA |
2398 | /* See linux-nat.h */ |
2399 | ||
2400 | void | |
2401 | linux_stop_and_wait_all_lwps (void) | |
2402 | { | |
2403 | /* Stop all LWP's ... */ | |
2404 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); | |
2405 | ||
2406 | /* ... and wait until all of them have reported back that | |
2407 | they're no longer running. */ | |
2408 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); | |
2409 | } | |
2410 | ||
2411 | /* See linux-nat.h */ | |
2412 | ||
2413 | void | |
2414 | linux_unstop_all_lwps (void) | |
2415 | { | |
2416 | iterate_over_lwps (minus_one_ptid, | |
2417 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
2418 | } | |
2419 | ||
57380f4e | 2420 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2421 | |
2422 | static int | |
57380f4e DJ |
2423 | linux_nat_has_pending_sigint (int pid) |
2424 | { | |
2425 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2426 | |
2427 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2428 | ||
2429 | if (sigismember (&pending, SIGINT) | |
2430 | && !sigismember (&ignored, SIGINT)) | |
2431 | return 1; | |
2432 | ||
2433 | return 0; | |
2434 | } | |
2435 | ||
2436 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2437 | ||
2438 | static int | |
2439 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2440 | { |
57380f4e DJ |
2441 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2442 | flag to consume the next one. */ | |
2443 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2444 | && WSTOPSIG (lp->status) == SIGINT) | |
2445 | lp->status = 0; | |
2446 | else | |
2447 | lp->ignore_sigint = 1; | |
2448 | ||
2449 | return 0; | |
2450 | } | |
2451 | ||
2452 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2453 | This function is called after we know the LWP has stopped; if the LWP | |
2454 | stopped before the expected SIGINT was delivered, then it will never have | |
2455 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2456 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2457 | |
57380f4e DJ |
2458 | static void |
2459 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2460 | { | |
2461 | if (!lp->ignore_sigint) | |
2462 | return; | |
2463 | ||
dfd4cc63 | 2464 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2465 | { |
2466 | if (debug_linux_nat) | |
2467 | fprintf_unfiltered (gdb_stdlog, | |
2468 | "MCIS: Clearing bogus flag for %s\n", | |
2469 | target_pid_to_str (lp->ptid)); | |
2470 | lp->ignore_sigint = 0; | |
2471 | } | |
2472 | } | |
2473 | ||
ebec9a0f PA |
2474 | /* Fetch the possible triggered data watchpoint info and store it in |
2475 | LP. | |
2476 | ||
2477 | On some archs, like x86, that use debug registers to set | |
2478 | watchpoints, it's possible that the way to know which watched | |
2479 | address trapped, is to check the register that is used to select | |
2480 | which address to watch. Problem is, between setting the watchpoint | |
2481 | and reading back which data address trapped, the user may change | |
2482 | the set of watchpoints, and, as a consequence, GDB changes the | |
2483 | debug registers in the inferior. To avoid reading back a stale | |
2484 | stopped-data-address when that happens, we cache in LP the fact | |
2485 | that a watchpoint trapped, and the corresponding data address, as | |
2486 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2487 | registers meanwhile, we have the cached data we can rely on. */ | |
2488 | ||
9c02b525 PA |
2489 | static int |
2490 | check_stopped_by_watchpoint (struct lwp_info *lp) | |
ebec9a0f PA |
2491 | { |
2492 | struct cleanup *old_chain; | |
2493 | ||
2494 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
9c02b525 | 2495 | return 0; |
ebec9a0f PA |
2496 | |
2497 | old_chain = save_inferior_ptid (); | |
2498 | inferior_ptid = lp->ptid; | |
2499 | ||
9c02b525 | 2500 | if (linux_ops->to_stopped_by_watchpoint (linux_ops)) |
ebec9a0f | 2501 | { |
15c66dd6 | 2502 | lp->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 | 2503 | |
ebec9a0f PA |
2504 | if (linux_ops->to_stopped_data_address != NULL) |
2505 | lp->stopped_data_address_p = | |
2506 | linux_ops->to_stopped_data_address (¤t_target, | |
2507 | &lp->stopped_data_address); | |
2508 | else | |
2509 | lp->stopped_data_address_p = 0; | |
2510 | } | |
2511 | ||
2512 | do_cleanups (old_chain); | |
9c02b525 | 2513 | |
15c66dd6 | 2514 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 PA |
2515 | } |
2516 | ||
2517 | /* Called when the LWP stopped for a trap that could be explained by a | |
2518 | watchpoint or a breakpoint. */ | |
2519 | ||
2520 | static void | |
2521 | save_sigtrap (struct lwp_info *lp) | |
2522 | { | |
15c66dd6 | 2523 | gdb_assert (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON); |
9c02b525 PA |
2524 | gdb_assert (lp->status != 0); |
2525 | ||
faf09f01 PA |
2526 | /* Check first if this was a SW/HW breakpoint before checking |
2527 | watchpoints, because at least s390 can't tell the data address of | |
2528 | hardware watchpoint hits, and the kernel returns | |
2529 | stopped-by-watchpoint as long as there's a watchpoint set. */ | |
9c02b525 PA |
2530 | if (linux_nat_status_is_event (lp->status)) |
2531 | check_stopped_by_breakpoint (lp); | |
faf09f01 PA |
2532 | |
2533 | /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint | |
2534 | or hardware watchpoint. Check which is which if we got | |
2535 | TARGET_STOPPED_BY_HW_BREAKPOINT. */ | |
2536 | if (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON | |
2537 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
2538 | check_stopped_by_watchpoint (lp); | |
ebec9a0f PA |
2539 | } |
2540 | ||
9c02b525 | 2541 | /* Returns true if the LWP had stopped for a watchpoint. */ |
ebec9a0f PA |
2542 | |
2543 | static int | |
6a109b6b | 2544 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2545 | { |
2546 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2547 | ||
2548 | gdb_assert (lp != NULL); | |
2549 | ||
15c66dd6 | 2550 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
ebec9a0f PA |
2551 | } |
2552 | ||
2553 | static int | |
2554 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2555 | { | |
2556 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2557 | ||
2558 | gdb_assert (lp != NULL); | |
2559 | ||
2560 | *addr_p = lp->stopped_data_address; | |
2561 | ||
2562 | return lp->stopped_data_address_p; | |
2563 | } | |
2564 | ||
26ab7092 JK |
2565 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2566 | ||
2567 | static int | |
2568 | sigtrap_is_event (int status) | |
2569 | { | |
2570 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2571 | } | |
2572 | ||
26ab7092 JK |
2573 | /* Set alternative SIGTRAP-like events recognizer. If |
2574 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2575 | applied. */ | |
2576 | ||
2577 | void | |
2578 | linux_nat_set_status_is_event (struct target_ops *t, | |
2579 | int (*status_is_event) (int status)) | |
2580 | { | |
2581 | linux_nat_status_is_event = status_is_event; | |
2582 | } | |
2583 | ||
57380f4e DJ |
2584 | /* Wait until LP is stopped. */ |
2585 | ||
2586 | static int | |
2587 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2588 | { | |
c9657e70 | 2589 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
6c95b8df PA |
2590 | |
2591 | /* If this is a vfork parent, bail out, it is not going to report | |
2592 | any SIGSTOP until the vfork is done with. */ | |
2593 | if (inf->vfork_child != NULL) | |
2594 | return 0; | |
2595 | ||
d6b0e80f AC |
2596 | if (!lp->stopped) |
2597 | { | |
2598 | int status; | |
2599 | ||
2600 | status = wait_lwp (lp); | |
2601 | if (status == 0) | |
2602 | return 0; | |
2603 | ||
57380f4e DJ |
2604 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2605 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2606 | { |
57380f4e | 2607 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2608 | |
2609 | errno = 0; | |
dfd4cc63 | 2610 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2611 | lp->stopped = 0; |
d6b0e80f AC |
2612 | if (debug_linux_nat) |
2613 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2614 | "PTRACE_CONT %s, 0, 0 (%s) " |
2615 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2616 | target_pid_to_str (lp->ptid), |
2617 | errno ? safe_strerror (errno) : "OK"); | |
2618 | ||
57380f4e | 2619 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2620 | } |
2621 | ||
57380f4e DJ |
2622 | maybe_clear_ignore_sigint (lp); |
2623 | ||
d6b0e80f AC |
2624 | if (WSTOPSIG (status) != SIGSTOP) |
2625 | { | |
e5ef252a | 2626 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2627 | |
e5ef252a PA |
2628 | if (debug_linux_nat) |
2629 | fprintf_unfiltered (gdb_stdlog, | |
2630 | "SWC: Pending event %s in %s\n", | |
2631 | status_to_str ((int) status), | |
2632 | target_pid_to_str (lp->ptid)); | |
2633 | ||
2634 | /* Save the sigtrap event. */ | |
2635 | lp->status = status; | |
e5ef252a | 2636 | gdb_assert (lp->signalled); |
9c02b525 | 2637 | save_sigtrap (lp); |
d6b0e80f AC |
2638 | } |
2639 | else | |
2640 | { | |
2641 | /* We caught the SIGSTOP that we intended to catch, so | |
2642 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2643 | |
2644 | if (debug_linux_nat) | |
2645 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2646 | "SWC: Expected SIGSTOP caught for %s.\n", |
e5ef252a PA |
2647 | target_pid_to_str (lp->ptid)); |
2648 | ||
e5ef252a PA |
2649 | /* Reset SIGNALLED only after the stop_wait_callback call |
2650 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2651 | lp->signalled = 0; |
2652 | } | |
2653 | } | |
2654 | ||
2655 | return 0; | |
2656 | } | |
2657 | ||
9c02b525 PA |
2658 | /* Return non-zero if LP has a wait status pending. Discard the |
2659 | pending event and resume the LWP if the event that originally | |
2660 | caused the stop became uninteresting. */ | |
d6b0e80f AC |
2661 | |
2662 | static int | |
2663 | status_callback (struct lwp_info *lp, void *data) | |
2664 | { | |
2665 | /* Only report a pending wait status if we pretend that this has | |
2666 | indeed been resumed. */ | |
ca2163eb PA |
2667 | if (!lp->resumed) |
2668 | return 0; | |
2669 | ||
eb54c8bf PA |
2670 | if (!lwp_status_pending_p (lp)) |
2671 | return 0; | |
2672 | ||
15c66dd6 PA |
2673 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
2674 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
9c02b525 PA |
2675 | { |
2676 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
2677 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2678 | CORE_ADDR pc; | |
2679 | int discard = 0; | |
2680 | ||
9c02b525 PA |
2681 | pc = regcache_read_pc (regcache); |
2682 | ||
2683 | if (pc != lp->stop_pc) | |
2684 | { | |
2685 | if (debug_linux_nat) | |
2686 | fprintf_unfiltered (gdb_stdlog, | |
2687 | "SC: PC of %s changed. was=%s, now=%s\n", | |
2688 | target_pid_to_str (lp->ptid), | |
2689 | paddress (target_gdbarch (), lp->stop_pc), | |
2690 | paddress (target_gdbarch (), pc)); | |
2691 | discard = 1; | |
2692 | } | |
faf09f01 PA |
2693 | |
2694 | #if !USE_SIGTRAP_SIGINFO | |
9c02b525 PA |
2695 | else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2696 | { | |
2697 | if (debug_linux_nat) | |
2698 | fprintf_unfiltered (gdb_stdlog, | |
2699 | "SC: previous breakpoint of %s, at %s gone\n", | |
2700 | target_pid_to_str (lp->ptid), | |
2701 | paddress (target_gdbarch (), lp->stop_pc)); | |
2702 | ||
2703 | discard = 1; | |
2704 | } | |
faf09f01 | 2705 | #endif |
9c02b525 PA |
2706 | |
2707 | if (discard) | |
2708 | { | |
2709 | if (debug_linux_nat) | |
2710 | fprintf_unfiltered (gdb_stdlog, | |
2711 | "SC: pending event of %s cancelled.\n", | |
2712 | target_pid_to_str (lp->ptid)); | |
2713 | ||
2714 | lp->status = 0; | |
2715 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); | |
2716 | return 0; | |
2717 | } | |
9c02b525 PA |
2718 | } |
2719 | ||
eb54c8bf | 2720 | return 1; |
d6b0e80f AC |
2721 | } |
2722 | ||
2723 | /* Return non-zero if LP isn't stopped. */ | |
2724 | ||
2725 | static int | |
2726 | running_callback (struct lwp_info *lp, void *data) | |
2727 | { | |
25289eb2 | 2728 | return (!lp->stopped |
8a99810d | 2729 | || (lwp_status_pending_p (lp) && lp->resumed)); |
d6b0e80f AC |
2730 | } |
2731 | ||
2732 | /* Count the LWP's that have had events. */ | |
2733 | ||
2734 | static int | |
2735 | count_events_callback (struct lwp_info *lp, void *data) | |
2736 | { | |
2737 | int *count = data; | |
2738 | ||
2739 | gdb_assert (count != NULL); | |
2740 | ||
9c02b525 PA |
2741 | /* Select only resumed LWPs that have an event pending. */ |
2742 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2743 | (*count)++; |
2744 | ||
2745 | return 0; | |
2746 | } | |
2747 | ||
2748 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2749 | ||
2750 | static int | |
2751 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2752 | { | |
25289eb2 PA |
2753 | if (lp->last_resume_kind == resume_step |
2754 | && lp->status != 0) | |
d6b0e80f AC |
2755 | return 1; |
2756 | else | |
2757 | return 0; | |
2758 | } | |
2759 | ||
8a99810d PA |
2760 | /* Returns true if LP has a status pending. */ |
2761 | ||
2762 | static int | |
2763 | lwp_status_pending_p (struct lwp_info *lp) | |
2764 | { | |
2765 | /* We check for lp->waitstatus in addition to lp->status, because we | |
2766 | can have pending process exits recorded in lp->status and | |
2767 | W_EXITCODE(0,0) happens to be 0. */ | |
2768 | return lp->status != 0 || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE; | |
2769 | } | |
2770 | ||
b90fc188 | 2771 | /* Select the Nth LWP that has had an event. */ |
d6b0e80f AC |
2772 | |
2773 | static int | |
2774 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2775 | { | |
2776 | int *selector = data; | |
2777 | ||
2778 | gdb_assert (selector != NULL); | |
2779 | ||
9c02b525 PA |
2780 | /* Select only resumed LWPs that have an event pending. */ |
2781 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2782 | if ((*selector)-- == 0) |
2783 | return 1; | |
2784 | ||
2785 | return 0; | |
2786 | } | |
2787 | ||
9c02b525 PA |
2788 | /* Called when the LWP got a signal/trap that could be explained by a |
2789 | software or hardware breakpoint. */ | |
2790 | ||
710151dd | 2791 | static int |
9c02b525 | 2792 | check_stopped_by_breakpoint (struct lwp_info *lp) |
710151dd PA |
2793 | { |
2794 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2795 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2796 | LWP. We will handle the current event, eventually we will resume | |
2797 | this LWP, and this breakpoint will trap again. | |
2798 | ||
2799 | If we do not do this, then we run the risk that the user will | |
2800 | delete or disable the breakpoint, but the LWP will have already | |
2801 | tripped on it. */ | |
2802 | ||
515630c5 UW |
2803 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2804 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2805 | CORE_ADDR pc; | |
9c02b525 | 2806 | CORE_ADDR sw_bp_pc; |
faf09f01 PA |
2807 | #if USE_SIGTRAP_SIGINFO |
2808 | siginfo_t siginfo; | |
2809 | #endif | |
9c02b525 PA |
2810 | |
2811 | pc = regcache_read_pc (regcache); | |
527a273a | 2812 | sw_bp_pc = pc - gdbarch_decr_pc_after_break (gdbarch); |
515630c5 | 2813 | |
faf09f01 PA |
2814 | #if USE_SIGTRAP_SIGINFO |
2815 | if (linux_nat_get_siginfo (lp->ptid, &siginfo)) | |
2816 | { | |
2817 | if (siginfo.si_signo == SIGTRAP) | |
2818 | { | |
2819 | if (siginfo.si_code == GDB_ARCH_TRAP_BRKPT) | |
2820 | { | |
2821 | if (debug_linux_nat) | |
2822 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d PA |
2823 | "CSBB: %s stopped by software " |
2824 | "breakpoint\n", | |
faf09f01 PA |
2825 | target_pid_to_str (lp->ptid)); |
2826 | ||
2827 | /* Back up the PC if necessary. */ | |
2828 | if (pc != sw_bp_pc) | |
2829 | regcache_write_pc (regcache, sw_bp_pc); | |
2830 | ||
2831 | lp->stop_pc = sw_bp_pc; | |
2832 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2833 | return 1; | |
2834 | } | |
2835 | else if (siginfo.si_code == TRAP_HWBKPT) | |
2836 | { | |
2837 | if (debug_linux_nat) | |
2838 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d PA |
2839 | "CSBB: %s stopped by hardware " |
2840 | "breakpoint/watchpoint\n", | |
faf09f01 PA |
2841 | target_pid_to_str (lp->ptid)); |
2842 | ||
2843 | lp->stop_pc = pc; | |
2844 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2845 | return 1; | |
2846 | } | |
2bf6fb9d PA |
2847 | else if (siginfo.si_code == TRAP_TRACE) |
2848 | { | |
2849 | if (debug_linux_nat) | |
2850 | fprintf_unfiltered (gdb_stdlog, | |
2851 | "CSBB: %s stopped by trace\n", | |
2852 | target_pid_to_str (lp->ptid)); | |
2853 | } | |
faf09f01 PA |
2854 | } |
2855 | } | |
2856 | #else | |
9c02b525 PA |
2857 | if ((!lp->step || lp->stop_pc == sw_bp_pc) |
2858 | && software_breakpoint_inserted_here_p (get_regcache_aspace (regcache), | |
2859 | sw_bp_pc)) | |
710151dd | 2860 | { |
9c02b525 PA |
2861 | /* The LWP was either continued, or stepped a software |
2862 | breakpoint instruction. */ | |
710151dd PA |
2863 | if (debug_linux_nat) |
2864 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2865 | "CSBB: %s stopped by software breakpoint\n", |
710151dd PA |
2866 | target_pid_to_str (lp->ptid)); |
2867 | ||
2868 | /* Back up the PC if necessary. */ | |
9c02b525 PA |
2869 | if (pc != sw_bp_pc) |
2870 | regcache_write_pc (regcache, sw_bp_pc); | |
515630c5 | 2871 | |
9c02b525 | 2872 | lp->stop_pc = sw_bp_pc; |
15c66dd6 | 2873 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
710151dd PA |
2874 | return 1; |
2875 | } | |
710151dd | 2876 | |
9c02b525 PA |
2877 | if (hardware_breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2878 | { | |
2879 | if (debug_linux_nat) | |
2880 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2881 | "CSBB: stopped by hardware breakpoint %s\n", |
9c02b525 | 2882 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 2883 | |
9c02b525 | 2884 | lp->stop_pc = pc; |
15c66dd6 | 2885 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; |
9c02b525 PA |
2886 | return 1; |
2887 | } | |
faf09f01 | 2888 | #endif |
d6b0e80f AC |
2889 | |
2890 | return 0; | |
2891 | } | |
2892 | ||
faf09f01 PA |
2893 | |
2894 | /* Returns true if the LWP had stopped for a software breakpoint. */ | |
2895 | ||
2896 | static int | |
2897 | linux_nat_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2898 | { | |
2899 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2900 | ||
2901 | gdb_assert (lp != NULL); | |
2902 | ||
2903 | return lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2904 | } | |
2905 | ||
2906 | /* Implement the supports_stopped_by_sw_breakpoint method. */ | |
2907 | ||
2908 | static int | |
2909 | linux_nat_supports_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2910 | { | |
2911 | return USE_SIGTRAP_SIGINFO; | |
2912 | } | |
2913 | ||
2914 | /* Returns true if the LWP had stopped for a hardware | |
2915 | breakpoint/watchpoint. */ | |
2916 | ||
2917 | static int | |
2918 | linux_nat_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2919 | { | |
2920 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2921 | ||
2922 | gdb_assert (lp != NULL); | |
2923 | ||
2924 | return lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2925 | } | |
2926 | ||
2927 | /* Implement the supports_stopped_by_hw_breakpoint method. */ | |
2928 | ||
2929 | static int | |
2930 | linux_nat_supports_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2931 | { | |
2932 | return USE_SIGTRAP_SIGINFO; | |
2933 | } | |
2934 | ||
d6b0e80f AC |
2935 | /* Select one LWP out of those that have events pending. */ |
2936 | ||
2937 | static void | |
d90e17a7 | 2938 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2939 | { |
2940 | int num_events = 0; | |
2941 | int random_selector; | |
9c02b525 | 2942 | struct lwp_info *event_lp = NULL; |
d6b0e80f | 2943 | |
ac264b3b | 2944 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2945 | (*orig_lp)->status = *status; |
2946 | ||
9c02b525 PA |
2947 | /* In all-stop, give preference to the LWP that is being |
2948 | single-stepped. There will be at most one, and it will be the | |
2949 | LWP that the core is most interested in. If we didn't do this, | |
2950 | then we'd have to handle pending step SIGTRAPs somehow in case | |
2951 | the core later continues the previously-stepped thread, as | |
2952 | otherwise we'd report the pending SIGTRAP then, and the core, not | |
2953 | having stepped the thread, wouldn't understand what the trap was | |
2954 | for, and therefore would report it to the user as a random | |
2955 | signal. */ | |
2956 | if (!non_stop) | |
d6b0e80f | 2957 | { |
9c02b525 PA |
2958 | event_lp = iterate_over_lwps (filter, |
2959 | select_singlestep_lwp_callback, NULL); | |
2960 | if (event_lp != NULL) | |
2961 | { | |
2962 | if (debug_linux_nat) | |
2963 | fprintf_unfiltered (gdb_stdlog, | |
2964 | "SEL: Select single-step %s\n", | |
2965 | target_pid_to_str (event_lp->ptid)); | |
2966 | } | |
d6b0e80f | 2967 | } |
9c02b525 PA |
2968 | |
2969 | if (event_lp == NULL) | |
d6b0e80f | 2970 | { |
9c02b525 | 2971 | /* Pick one at random, out of those which have had events. */ |
d6b0e80f | 2972 | |
9c02b525 | 2973 | /* First see how many events we have. */ |
d90e17a7 | 2974 | iterate_over_lwps (filter, count_events_callback, &num_events); |
8bf3b159 | 2975 | gdb_assert (num_events > 0); |
d6b0e80f | 2976 | |
9c02b525 PA |
2977 | /* Now randomly pick a LWP out of those that have had |
2978 | events. */ | |
d6b0e80f AC |
2979 | random_selector = (int) |
2980 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2981 | ||
2982 | if (debug_linux_nat && num_events > 1) | |
2983 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2984 | "SEL: Found %d events, selecting #%d\n", |
d6b0e80f AC |
2985 | num_events, random_selector); |
2986 | ||
d90e17a7 PA |
2987 | event_lp = iterate_over_lwps (filter, |
2988 | select_event_lwp_callback, | |
d6b0e80f AC |
2989 | &random_selector); |
2990 | } | |
2991 | ||
2992 | if (event_lp != NULL) | |
2993 | { | |
2994 | /* Switch the event LWP. */ | |
2995 | *orig_lp = event_lp; | |
2996 | *status = event_lp->status; | |
2997 | } | |
2998 | ||
2999 | /* Flush the wait status for the event LWP. */ | |
3000 | (*orig_lp)->status = 0; | |
3001 | } | |
3002 | ||
3003 | /* Return non-zero if LP has been resumed. */ | |
3004 | ||
3005 | static int | |
3006 | resumed_callback (struct lwp_info *lp, void *data) | |
3007 | { | |
3008 | return lp->resumed; | |
3009 | } | |
3010 | ||
12d9289a PA |
3011 | /* Stop an active thread, verify it still exists, then resume it. If |
3012 | the thread ends up with a pending status, then it is not resumed, | |
3013 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
3014 | |
3015 | static int | |
3016 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
3017 | { | |
25289eb2 | 3018 | if (!lp->stopped) |
d6b0e80f | 3019 | { |
25289eb2 PA |
3020 | ptid_t ptid = lp->ptid; |
3021 | ||
d6b0e80f AC |
3022 | stop_callback (lp, NULL); |
3023 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
3024 | |
3025 | /* Resume if the lwp still exists, and the core wanted it | |
3026 | running. */ | |
12d9289a PA |
3027 | lp = find_lwp_pid (ptid); |
3028 | if (lp != NULL) | |
25289eb2 | 3029 | { |
12d9289a | 3030 | if (lp->last_resume_kind == resume_stop |
8a99810d | 3031 | && !lwp_status_pending_p (lp)) |
12d9289a PA |
3032 | { |
3033 | /* The core wanted the LWP to stop. Even if it stopped | |
3034 | cleanly (with SIGSTOP), leave the event pending. */ | |
3035 | if (debug_linux_nat) | |
3036 | fprintf_unfiltered (gdb_stdlog, | |
3037 | "SARC: core wanted LWP %ld stopped " | |
3038 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 3039 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
3040 | lp->status = W_STOPCODE (SIGSTOP); |
3041 | } | |
3042 | ||
8a99810d | 3043 | if (!lwp_status_pending_p (lp)) |
12d9289a PA |
3044 | { |
3045 | if (debug_linux_nat) | |
3046 | fprintf_unfiltered (gdb_stdlog, | |
3047 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 3048 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 3049 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
3050 | } |
3051 | else | |
3052 | { | |
3053 | if (debug_linux_nat) | |
3054 | fprintf_unfiltered (gdb_stdlog, | |
3055 | "SARC: not re-resuming LWP %ld " | |
3056 | "(has pending)\n", | |
dfd4cc63 | 3057 | ptid_get_lwp (lp->ptid)); |
12d9289a | 3058 | } |
25289eb2 | 3059 | } |
d6b0e80f AC |
3060 | } |
3061 | return 0; | |
3062 | } | |
3063 | ||
02f3fc28 | 3064 | /* Check if we should go on and pass this event to common code. |
9c02b525 | 3065 | Return the affected lwp if we are, or NULL otherwise. */ |
12d9289a | 3066 | |
02f3fc28 | 3067 | static struct lwp_info * |
9c02b525 | 3068 | linux_nat_filter_event (int lwpid, int status) |
02f3fc28 PA |
3069 | { |
3070 | struct lwp_info *lp; | |
89a5711c | 3071 | int event = linux_ptrace_get_extended_event (status); |
02f3fc28 PA |
3072 | |
3073 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
3074 | ||
3075 | /* Check for stop events reported by a process we didn't already | |
3076 | know about - anything not already in our LWP list. | |
3077 | ||
3078 | If we're expecting to receive stopped processes after | |
3079 | fork, vfork, and clone events, then we'll just add the | |
3080 | new one to our list and go back to waiting for the event | |
3081 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
3082 | from waitpid before or after the event is. |
3083 | ||
3084 | But note the case of a non-leader thread exec'ing after the | |
3085 | leader having exited, and gone from our lists. The non-leader | |
3086 | thread changes its tid to the tgid. */ | |
3087 | ||
3088 | if (WIFSTOPPED (status) && lp == NULL | |
89a5711c | 3089 | && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC)) |
0e5bf2a8 PA |
3090 | { |
3091 | /* A multi-thread exec after we had seen the leader exiting. */ | |
3092 | if (debug_linux_nat) | |
3093 | fprintf_unfiltered (gdb_stdlog, | |
3094 | "LLW: Re-adding thread group leader LWP %d.\n", | |
3095 | lwpid); | |
3096 | ||
dfd4cc63 | 3097 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
3098 | lp->stopped = 1; |
3099 | lp->resumed = 1; | |
3100 | add_thread (lp->ptid); | |
3101 | } | |
3102 | ||
02f3fc28 PA |
3103 | if (WIFSTOPPED (status) && !lp) |
3104 | { | |
3b27ef47 PA |
3105 | if (debug_linux_nat) |
3106 | fprintf_unfiltered (gdb_stdlog, | |
3107 | "LHEW: saving LWP %ld status %s in stopped_pids list\n", | |
3108 | (long) lwpid, status_to_str (status)); | |
84636d28 | 3109 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
3110 | return NULL; |
3111 | } | |
3112 | ||
3113 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 3114 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 3115 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
3116 | exits. */ |
3117 | if (!WIFSTOPPED (status) && !lp) | |
3118 | return NULL; | |
3119 | ||
8817a6f2 PA |
3120 | /* This LWP is stopped now. (And if dead, this prevents it from |
3121 | ever being continued.) */ | |
3122 | lp->stopped = 1; | |
3123 | ||
8784d563 PA |
3124 | if (WIFSTOPPED (status) && lp->must_set_ptrace_flags) |
3125 | { | |
3126 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
de0d863e | 3127 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 3128 | |
de0d863e | 3129 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), options); |
8784d563 PA |
3130 | lp->must_set_ptrace_flags = 0; |
3131 | } | |
3132 | ||
ca2163eb PA |
3133 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
3134 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
3135 | { | |
3136 | /* No longer need the sysgood bit. The ptrace event ends up | |
3137 | recorded in lp->waitstatus if we care for it. We can carry | |
3138 | on handling the event like a regular SIGTRAP from here | |
3139 | on. */ | |
3140 | status = W_STOPCODE (SIGTRAP); | |
3141 | if (linux_handle_syscall_trap (lp, 0)) | |
3142 | return NULL; | |
3143 | } | |
02f3fc28 | 3144 | |
ca2163eb | 3145 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
3146 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
3147 | && linux_is_extended_waitstatus (status)) | |
02f3fc28 PA |
3148 | { |
3149 | if (debug_linux_nat) | |
3150 | fprintf_unfiltered (gdb_stdlog, | |
3151 | "LLW: Handling extended status 0x%06x\n", | |
3152 | status); | |
3153 | if (linux_handle_extended_wait (lp, status, 0)) | |
3154 | return NULL; | |
3155 | } | |
3156 | ||
3157 | /* Check if the thread has exited. */ | |
9c02b525 PA |
3158 | if (WIFEXITED (status) || WIFSIGNALED (status)) |
3159 | { | |
3160 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
02f3fc28 | 3161 | { |
9c02b525 PA |
3162 | /* If this is the main thread, we must stop all threads and |
3163 | verify if they are still alive. This is because in the | |
3164 | nptl thread model on Linux 2.4, there is no signal issued | |
3165 | for exiting LWPs other than the main thread. We only get | |
3166 | the main thread exit signal once all child threads have | |
3167 | already exited. If we stop all the threads and use the | |
3168 | stop_wait_callback to check if they have exited we can | |
3169 | determine whether this signal should be ignored or | |
3170 | whether it means the end of the debugged application, | |
3171 | regardless of which threading model is being used. */ | |
3172 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) | |
3173 | { | |
3174 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3175 | stop_and_resume_callback, NULL); | |
3176 | } | |
3177 | ||
3178 | if (debug_linux_nat) | |
3179 | fprintf_unfiltered (gdb_stdlog, | |
3180 | "LLW: %s exited.\n", | |
3181 | target_pid_to_str (lp->ptid)); | |
3182 | ||
3183 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
3184 | { | |
3185 | /* If there is at least one more LWP, then the exit signal | |
3186 | was not the end of the debugged application and should be | |
3187 | ignored. */ | |
3188 | exit_lwp (lp); | |
3189 | return NULL; | |
3190 | } | |
02f3fc28 PA |
3191 | } |
3192 | ||
9c02b525 PA |
3193 | gdb_assert (lp->resumed); |
3194 | ||
02f3fc28 PA |
3195 | if (debug_linux_nat) |
3196 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 PA |
3197 | "Process %ld exited\n", |
3198 | ptid_get_lwp (lp->ptid)); | |
02f3fc28 | 3199 | |
9c02b525 PA |
3200 | /* This was the last lwp in the process. Since events are |
3201 | serialized to GDB core, we may not be able report this one | |
3202 | right now, but GDB core and the other target layers will want | |
3203 | to be notified about the exit code/signal, leave the status | |
3204 | pending for the next time we're able to report it. */ | |
3205 | ||
3206 | /* Dead LWP's aren't expected to reported a pending sigstop. */ | |
3207 | lp->signalled = 0; | |
3208 | ||
3209 | /* Store the pending event in the waitstatus, because | |
3210 | W_EXITCODE(0,0) == 0. */ | |
3211 | store_waitstatus (&lp->waitstatus, status); | |
3212 | return lp; | |
02f3fc28 PA |
3213 | } |
3214 | ||
3215 | /* Check if the current LWP has previously exited. In the nptl | |
3216 | thread model, LWPs other than the main thread do not issue | |
3217 | signals when they exit so we must check whenever the thread has | |
3218 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3219 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3220 | { |
dfd4cc63 | 3221 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3222 | |
02f3fc28 PA |
3223 | if (debug_linux_nat) |
3224 | fprintf_unfiltered (gdb_stdlog, | |
3225 | "LLW: %s exited.\n", | |
3226 | target_pid_to_str (lp->ptid)); | |
3227 | ||
3228 | exit_lwp (lp); | |
3229 | ||
3230 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3231 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3232 | |
3233 | /* Discard the event. */ | |
3234 | return NULL; | |
3235 | } | |
3236 | ||
3237 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3238 | an attempt to stop an LWP. */ | |
3239 | if (lp->signalled | |
3240 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3241 | { | |
02f3fc28 PA |
3242 | lp->signalled = 0; |
3243 | ||
2bf6fb9d | 3244 | if (lp->last_resume_kind == resume_stop) |
25289eb2 | 3245 | { |
2bf6fb9d PA |
3246 | if (debug_linux_nat) |
3247 | fprintf_unfiltered (gdb_stdlog, | |
3248 | "LLW: resume_stop SIGSTOP caught for %s.\n", | |
3249 | target_pid_to_str (lp->ptid)); | |
3250 | } | |
3251 | else | |
3252 | { | |
3253 | /* This is a delayed SIGSTOP. Filter out the event. */ | |
02f3fc28 | 3254 | |
25289eb2 PA |
3255 | if (debug_linux_nat) |
3256 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 3257 | "LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n", |
25289eb2 PA |
3258 | lp->step ? |
3259 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3260 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3261 | |
2bf6fb9d | 3262 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
25289eb2 | 3263 | gdb_assert (lp->resumed); |
25289eb2 PA |
3264 | return NULL; |
3265 | } | |
02f3fc28 PA |
3266 | } |
3267 | ||
57380f4e DJ |
3268 | /* Make sure we don't report a SIGINT that we have already displayed |
3269 | for another thread. */ | |
3270 | if (lp->ignore_sigint | |
3271 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3272 | { | |
3273 | if (debug_linux_nat) | |
3274 | fprintf_unfiltered (gdb_stdlog, | |
3275 | "LLW: Delayed SIGINT caught for %s.\n", | |
3276 | target_pid_to_str (lp->ptid)); | |
3277 | ||
3278 | /* This is a delayed SIGINT. */ | |
3279 | lp->ignore_sigint = 0; | |
3280 | ||
8a99810d | 3281 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3282 | if (debug_linux_nat) |
3283 | fprintf_unfiltered (gdb_stdlog, | |
3284 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3285 | lp->step ? | |
3286 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3287 | target_pid_to_str (lp->ptid)); | |
57380f4e DJ |
3288 | gdb_assert (lp->resumed); |
3289 | ||
3290 | /* Discard the event. */ | |
3291 | return NULL; | |
3292 | } | |
3293 | ||
9c02b525 PA |
3294 | /* Don't report signals that GDB isn't interested in, such as |
3295 | signals that are neither printed nor stopped upon. Stopping all | |
3296 | threads can be a bit time-consuming so if we want decent | |
3297 | performance with heavily multi-threaded programs, especially when | |
3298 | they're using a high frequency timer, we'd better avoid it if we | |
3299 | can. */ | |
3300 | if (WIFSTOPPED (status)) | |
3301 | { | |
3302 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); | |
3303 | ||
3304 | if (!non_stop) | |
3305 | { | |
3306 | /* Only do the below in all-stop, as we currently use SIGSTOP | |
3307 | to implement target_stop (see linux_nat_stop) in | |
3308 | non-stop. */ | |
3309 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) | |
3310 | { | |
3311 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3312 | forwarded to the entire process group, that is, all LWPs | |
3313 | will receive it - unless they're using CLONE_THREAD to | |
3314 | share signals. Since we only want to report it once, we | |
3315 | mark it as ignored for all LWPs except this one. */ | |
3316 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3317 | set_ignore_sigint, NULL); | |
3318 | lp->ignore_sigint = 0; | |
3319 | } | |
3320 | else | |
3321 | maybe_clear_ignore_sigint (lp); | |
3322 | } | |
3323 | ||
3324 | /* When using hardware single-step, we need to report every signal. | |
c9587f88 AT |
3325 | Otherwise, signals in pass_mask may be short-circuited |
3326 | except signals that might be caused by a breakpoint. */ | |
9c02b525 | 3327 | if (!lp->step |
c9587f88 AT |
3328 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)) |
3329 | && !linux_wstatus_maybe_breakpoint (status)) | |
9c02b525 PA |
3330 | { |
3331 | linux_resume_one_lwp (lp, lp->step, signo); | |
3332 | if (debug_linux_nat) | |
3333 | fprintf_unfiltered (gdb_stdlog, | |
3334 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3335 | lp->step ? | |
3336 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3337 | target_pid_to_str (lp->ptid), | |
3338 | (signo != GDB_SIGNAL_0 | |
3339 | ? strsignal (gdb_signal_to_host (signo)) | |
3340 | : "0")); | |
3341 | return NULL; | |
3342 | } | |
3343 | } | |
3344 | ||
02f3fc28 PA |
3345 | /* An interesting event. */ |
3346 | gdb_assert (lp); | |
ca2163eb | 3347 | lp->status = status; |
9c02b525 | 3348 | save_sigtrap (lp); |
02f3fc28 PA |
3349 | return lp; |
3350 | } | |
3351 | ||
0e5bf2a8 PA |
3352 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3353 | their exits until all other threads in the group have exited. */ | |
3354 | ||
3355 | static void | |
3356 | check_zombie_leaders (void) | |
3357 | { | |
3358 | struct inferior *inf; | |
3359 | ||
3360 | ALL_INFERIORS (inf) | |
3361 | { | |
3362 | struct lwp_info *leader_lp; | |
3363 | ||
3364 | if (inf->pid == 0) | |
3365 | continue; | |
3366 | ||
3367 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3368 | if (leader_lp != NULL | |
3369 | /* Check if there are other threads in the group, as we may | |
3370 | have raced with the inferior simply exiting. */ | |
3371 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3372 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3373 | { |
3374 | if (debug_linux_nat) | |
3375 | fprintf_unfiltered (gdb_stdlog, | |
3376 | "CZL: Thread group leader %d zombie " | |
3377 | "(it exited, or another thread execd).\n", | |
3378 | inf->pid); | |
3379 | ||
3380 | /* A leader zombie can mean one of two things: | |
3381 | ||
3382 | - It exited, and there's an exit status pending | |
3383 | available, or only the leader exited (not the whole | |
3384 | program). In the latter case, we can't waitpid the | |
3385 | leader's exit status until all other threads are gone. | |
3386 | ||
3387 | - There are 3 or more threads in the group, and a thread | |
3388 | other than the leader exec'd. On an exec, the Linux | |
3389 | kernel destroys all other threads (except the execing | |
3390 | one) in the thread group, and resets the execing thread's | |
3391 | tid to the tgid. No exit notification is sent for the | |
3392 | execing thread -- from the ptracer's perspective, it | |
3393 | appears as though the execing thread just vanishes. | |
3394 | Until we reap all other threads except the leader and the | |
3395 | execing thread, the leader will be zombie, and the | |
3396 | execing thread will be in `D (disc sleep)'. As soon as | |
3397 | all other threads are reaped, the execing thread changes | |
3398 | it's tid to the tgid, and the previous (zombie) leader | |
3399 | vanishes, giving place to the "new" leader. We could try | |
3400 | distinguishing the exit and exec cases, by waiting once | |
3401 | more, and seeing if something comes out, but it doesn't | |
3402 | sound useful. The previous leader _does_ go away, and | |
3403 | we'll re-add the new one once we see the exec event | |
3404 | (which is just the same as what would happen if the | |
3405 | previous leader did exit voluntarily before some other | |
3406 | thread execs). */ | |
3407 | ||
3408 | if (debug_linux_nat) | |
3409 | fprintf_unfiltered (gdb_stdlog, | |
3410 | "CZL: Thread group leader %d vanished.\n", | |
3411 | inf->pid); | |
3412 | exit_lwp (leader_lp); | |
3413 | } | |
3414 | } | |
3415 | } | |
3416 | ||
d6b0e80f | 3417 | static ptid_t |
7feb7d06 | 3418 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3419 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3420 | int target_options) | |
d6b0e80f | 3421 | { |
fc9b8e47 | 3422 | sigset_t prev_mask; |
4b60df3d | 3423 | enum resume_kind last_resume_kind; |
12d9289a | 3424 | struct lwp_info *lp; |
12d9289a | 3425 | int status; |
d6b0e80f | 3426 | |
01124a23 | 3427 | if (debug_linux_nat) |
b84876c2 PA |
3428 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3429 | ||
f973ed9c DJ |
3430 | /* The first time we get here after starting a new inferior, we may |
3431 | not have added it to the LWP list yet - this is the earliest | |
3432 | moment at which we know its PID. */ | |
d90e17a7 | 3433 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3434 | { |
27c9d204 PA |
3435 | /* Upgrade the main thread's ptid. */ |
3436 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3437 | ptid_build (ptid_get_pid (inferior_ptid), |
3438 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3439 | |
26cb8b7c | 3440 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3441 | lp->resumed = 1; |
3442 | } | |
3443 | ||
12696c10 | 3444 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3445 | block_child_signals (&prev_mask); |
d6b0e80f | 3446 | |
d6b0e80f | 3447 | /* First check if there is a LWP with a wait status pending. */ |
8a99810d PA |
3448 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3449 | if (lp != NULL) | |
d6b0e80f AC |
3450 | { |
3451 | if (debug_linux_nat) | |
d6b0e80f AC |
3452 | fprintf_unfiltered (gdb_stdlog, |
3453 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3454 | status_to_str (lp->status), |
d6b0e80f | 3455 | target_pid_to_str (lp->ptid)); |
d6b0e80f AC |
3456 | } |
3457 | ||
d9d41e78 | 3458 | if (!target_is_async_p ()) |
b84876c2 PA |
3459 | { |
3460 | /* Causes SIGINT to be passed on to the attached process. */ | |
3461 | set_sigint_trap (); | |
b84876c2 | 3462 | } |
d6b0e80f | 3463 | |
9c02b525 PA |
3464 | /* But if we don't find a pending event, we'll have to wait. Always |
3465 | pull all events out of the kernel. We'll randomly select an | |
3466 | event LWP out of all that have events, to prevent starvation. */ | |
7feb7d06 | 3467 | |
d90e17a7 | 3468 | while (lp == NULL) |
d6b0e80f AC |
3469 | { |
3470 | pid_t lwpid; | |
3471 | ||
0e5bf2a8 PA |
3472 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3473 | quirks: | |
3474 | ||
3475 | - If the thread group leader exits while other threads in the | |
3476 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3477 | waitpid won't return an exit status until the other threads | |
3478 | in the group are reapped. | |
3479 | ||
3480 | - When a non-leader thread execs, that thread just vanishes | |
3481 | without reporting an exit (so we'd hang if we waited for it | |
3482 | explicitly in that case). The exec event is reported to | |
3483 | the TGID pid. */ | |
3484 | ||
3485 | errno = 0; | |
3486 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3487 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3488 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3489 | ||
3490 | if (debug_linux_nat) | |
3491 | fprintf_unfiltered (gdb_stdlog, | |
3492 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3493 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3494 | |
d6b0e80f AC |
3495 | if (lwpid > 0) |
3496 | { | |
d6b0e80f AC |
3497 | if (debug_linux_nat) |
3498 | { | |
3499 | fprintf_unfiltered (gdb_stdlog, | |
3500 | "LLW: waitpid %ld received %s\n", | |
3501 | (long) lwpid, status_to_str (status)); | |
3502 | } | |
3503 | ||
9c02b525 | 3504 | linux_nat_filter_event (lwpid, status); |
0e5bf2a8 PA |
3505 | /* Retry until nothing comes out of waitpid. A single |
3506 | SIGCHLD can indicate more than one child stopped. */ | |
3507 | continue; | |
d6b0e80f AC |
3508 | } |
3509 | ||
20ba1ce6 PA |
3510 | /* Now that we've pulled all events out of the kernel, resume |
3511 | LWPs that don't have an interesting event to report. */ | |
3512 | iterate_over_lwps (minus_one_ptid, | |
3513 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
3514 | ||
3515 | /* ... and find an LWP with a status to report to the core, if | |
3516 | any. */ | |
9c02b525 PA |
3517 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3518 | if (lp != NULL) | |
3519 | break; | |
3520 | ||
0e5bf2a8 PA |
3521 | /* Check for zombie thread group leaders. Those can't be reaped |
3522 | until all other threads in the thread group are. */ | |
3523 | check_zombie_leaders (); | |
d6b0e80f | 3524 | |
0e5bf2a8 PA |
3525 | /* If there are no resumed children left, bail. We'd be stuck |
3526 | forever in the sigsuspend call below otherwise. */ | |
3527 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3528 | { | |
3529 | if (debug_linux_nat) | |
3530 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3531 | |
0e5bf2a8 | 3532 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3533 | |
d9d41e78 | 3534 | if (!target_is_async_p ()) |
0e5bf2a8 | 3535 | clear_sigint_trap (); |
b84876c2 | 3536 | |
0e5bf2a8 PA |
3537 | restore_child_signals_mask (&prev_mask); |
3538 | return minus_one_ptid; | |
d6b0e80f | 3539 | } |
28736962 | 3540 | |
0e5bf2a8 PA |
3541 | /* No interesting event to report to the core. */ |
3542 | ||
3543 | if (target_options & TARGET_WNOHANG) | |
3544 | { | |
01124a23 | 3545 | if (debug_linux_nat) |
28736962 PA |
3546 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3547 | ||
0e5bf2a8 | 3548 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3549 | restore_child_signals_mask (&prev_mask); |
3550 | return minus_one_ptid; | |
3551 | } | |
d6b0e80f AC |
3552 | |
3553 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3554 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3555 | |
3556 | /* Block until we get an event reported with SIGCHLD. */ | |
d36bf488 DE |
3557 | if (debug_linux_nat) |
3558 | fprintf_unfiltered (gdb_stdlog, "LNW: about to sigsuspend\n"); | |
0e5bf2a8 | 3559 | sigsuspend (&suspend_mask); |
d6b0e80f AC |
3560 | } |
3561 | ||
d9d41e78 | 3562 | if (!target_is_async_p ()) |
d26b5354 | 3563 | clear_sigint_trap (); |
d6b0e80f AC |
3564 | |
3565 | gdb_assert (lp); | |
3566 | ||
ca2163eb PA |
3567 | status = lp->status; |
3568 | lp->status = 0; | |
3569 | ||
4c28f408 PA |
3570 | if (!non_stop) |
3571 | { | |
3572 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3573 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3574 | |
3575 | /* ... and wait until all of them have reported back that | |
3576 | they're no longer running. */ | |
d90e17a7 | 3577 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
9c02b525 PA |
3578 | } |
3579 | ||
3580 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
3581 | among those that have had events. Giving equal priority to all | |
3582 | LWPs that have had events helps prevent starvation. */ | |
3583 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) | |
3584 | select_event_lwp (ptid, &lp, &status); | |
3585 | ||
3586 | gdb_assert (lp != NULL); | |
3587 | ||
3588 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
faf09f01 PA |
3589 | it was a software breakpoint, and we can't reliably support the |
3590 | "stopped by software breakpoint" stop reason. */ | |
3591 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3592 | && !USE_SIGTRAP_SIGINFO) | |
9c02b525 PA |
3593 | { |
3594 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
3595 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
527a273a | 3596 | int decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
4c28f408 | 3597 | |
9c02b525 PA |
3598 | if (decr_pc != 0) |
3599 | { | |
3600 | CORE_ADDR pc; | |
d6b0e80f | 3601 | |
9c02b525 PA |
3602 | pc = regcache_read_pc (regcache); |
3603 | regcache_write_pc (regcache, pc + decr_pc); | |
3604 | } | |
3605 | } | |
e3e9f5a2 | 3606 | |
9c02b525 PA |
3607 | /* We'll need this to determine whether to report a SIGSTOP as |
3608 | GDB_SIGNAL_0. Need to take a copy because resume_clear_callback | |
3609 | clears it. */ | |
3610 | last_resume_kind = lp->last_resume_kind; | |
4b60df3d | 3611 | |
9c02b525 PA |
3612 | if (!non_stop) |
3613 | { | |
e3e9f5a2 PA |
3614 | /* In all-stop, from the core's perspective, all LWPs are now |
3615 | stopped until a new resume action is sent over. */ | |
3616 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3617 | } | |
3618 | else | |
25289eb2 | 3619 | { |
4b60df3d | 3620 | resume_clear_callback (lp, NULL); |
25289eb2 | 3621 | } |
d6b0e80f | 3622 | |
26ab7092 | 3623 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3624 | { |
d6b0e80f AC |
3625 | if (debug_linux_nat) |
3626 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3627 | "LLW: trap ptid is %s.\n", |
3628 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3629 | } |
d6b0e80f AC |
3630 | |
3631 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3632 | { | |
3633 | *ourstatus = lp->waitstatus; | |
3634 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3635 | } | |
3636 | else | |
3637 | store_waitstatus (ourstatus, status); | |
3638 | ||
01124a23 | 3639 | if (debug_linux_nat) |
b84876c2 PA |
3640 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3641 | ||
7feb7d06 | 3642 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3643 | |
4b60df3d | 3644 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3645 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3646 | && WSTOPSIG (status) == SIGSTOP) | |
3647 | { | |
3648 | /* A thread that has been requested to stop by GDB with | |
3649 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3650 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3651 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3652 | } |
3653 | ||
1e225492 JK |
3654 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3655 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3656 | lp->core = -1; | |
3657 | else | |
2e794194 | 3658 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3659 | |
f973ed9c | 3660 | return lp->ptid; |
d6b0e80f AC |
3661 | } |
3662 | ||
e3e9f5a2 PA |
3663 | /* Resume LWPs that are currently stopped without any pending status |
3664 | to report, but are resumed from the core's perspective. */ | |
3665 | ||
3666 | static int | |
3667 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3668 | { | |
3669 | ptid_t *wait_ptid_p = data; | |
3670 | ||
3671 | if (lp->stopped | |
3672 | && lp->resumed | |
8a99810d | 3673 | && !lwp_status_pending_p (lp)) |
e3e9f5a2 | 3674 | { |
336060f3 PA |
3675 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3676 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
336060f3 | 3677 | |
23f238d3 | 3678 | TRY |
e3e9f5a2 | 3679 | { |
23f238d3 PA |
3680 | CORE_ADDR pc = regcache_read_pc (regcache); |
3681 | int leave_stopped = 0; | |
e3e9f5a2 | 3682 | |
23f238d3 PA |
3683 | /* Don't bother if there's a breakpoint at PC that we'd hit |
3684 | immediately, and we're not waiting for this LWP. */ | |
3685 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3686 | { | |
3687 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) | |
3688 | leave_stopped = 1; | |
3689 | } | |
e3e9f5a2 | 3690 | |
23f238d3 PA |
3691 | if (!leave_stopped) |
3692 | { | |
3693 | if (debug_linux_nat) | |
3694 | fprintf_unfiltered (gdb_stdlog, | |
3695 | "RSRL: resuming stopped-resumed LWP %s at " | |
3696 | "%s: step=%d\n", | |
3697 | target_pid_to_str (lp->ptid), | |
3698 | paddress (gdbarch, pc), | |
3699 | lp->step); | |
3700 | ||
3701 | linux_resume_one_lwp_throw (lp, lp->step, GDB_SIGNAL_0); | |
3702 | } | |
3703 | } | |
3704 | CATCH (ex, RETURN_MASK_ERROR) | |
3705 | { | |
3706 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
3707 | throw_exception (ex); | |
3708 | } | |
3709 | END_CATCH | |
e3e9f5a2 PA |
3710 | } |
3711 | ||
3712 | return 0; | |
3713 | } | |
3714 | ||
7feb7d06 PA |
3715 | static ptid_t |
3716 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3717 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3718 | int target_options) | |
7feb7d06 PA |
3719 | { |
3720 | ptid_t event_ptid; | |
3721 | ||
3722 | if (debug_linux_nat) | |
09826ec5 PA |
3723 | { |
3724 | char *options_string; | |
3725 | ||
3726 | options_string = target_options_to_string (target_options); | |
3727 | fprintf_unfiltered (gdb_stdlog, | |
3728 | "linux_nat_wait: [%s], [%s]\n", | |
3729 | target_pid_to_str (ptid), | |
3730 | options_string); | |
3731 | xfree (options_string); | |
3732 | } | |
7feb7d06 PA |
3733 | |
3734 | /* Flush the async file first. */ | |
d9d41e78 | 3735 | if (target_is_async_p ()) |
7feb7d06 PA |
3736 | async_file_flush (); |
3737 | ||
e3e9f5a2 PA |
3738 | /* Resume LWPs that are currently stopped without any pending status |
3739 | to report, but are resumed from the core's perspective. LWPs get | |
3740 | in this state if we find them stopping at a time we're not | |
3741 | interested in reporting the event (target_wait on a | |
3742 | specific_process, for example, see linux_nat_wait_1), and | |
3743 | meanwhile the event became uninteresting. Don't bother resuming | |
3744 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3745 | if (non_stop) | |
3746 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3747 | ||
47608cb1 | 3748 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3749 | |
3750 | /* If we requested any event, and something came out, assume there | |
3751 | may be more. If we requested a specific lwp or process, also | |
3752 | assume there may be more. */ | |
d9d41e78 | 3753 | if (target_is_async_p () |
6953d224 PA |
3754 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3755 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3756 | || !ptid_equal (ptid, minus_one_ptid))) |
3757 | async_file_mark (); | |
3758 | ||
7feb7d06 PA |
3759 | return event_ptid; |
3760 | } | |
3761 | ||
d6b0e80f AC |
3762 | static int |
3763 | kill_callback (struct lwp_info *lp, void *data) | |
3764 | { | |
ed731959 JK |
3765 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3766 | ||
3767 | errno = 0; | |
69ff6be5 | 3768 | kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 | 3769 | if (debug_linux_nat) |
57745c90 PA |
3770 | { |
3771 | int save_errno = errno; | |
3772 | ||
3773 | fprintf_unfiltered (gdb_stdlog, | |
3774 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3775 | target_pid_to_str (lp->ptid), | |
3776 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3777 | } | |
ed731959 JK |
3778 | |
3779 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3780 | ||
d6b0e80f | 3781 | errno = 0; |
dfd4cc63 | 3782 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f | 3783 | if (debug_linux_nat) |
57745c90 PA |
3784 | { |
3785 | int save_errno = errno; | |
3786 | ||
3787 | fprintf_unfiltered (gdb_stdlog, | |
3788 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3789 | target_pid_to_str (lp->ptid), | |
3790 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3791 | } | |
d6b0e80f AC |
3792 | |
3793 | return 0; | |
3794 | } | |
3795 | ||
3796 | static int | |
3797 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3798 | { | |
3799 | pid_t pid; | |
3800 | ||
3801 | /* We must make sure that there are no pending events (delayed | |
3802 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3803 | program doesn't interfere with any following debugging session. */ | |
3804 | ||
3805 | /* For cloned processes we must check both with __WCLONE and | |
3806 | without, since the exit status of a cloned process isn't reported | |
3807 | with __WCLONE. */ | |
3808 | if (lp->cloned) | |
3809 | { | |
3810 | do | |
3811 | { | |
dfd4cc63 | 3812 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3813 | if (pid != (pid_t) -1) |
d6b0e80f | 3814 | { |
e85a822c DJ |
3815 | if (debug_linux_nat) |
3816 | fprintf_unfiltered (gdb_stdlog, | |
3817 | "KWC: wait %s received unknown.\n", | |
3818 | target_pid_to_str (lp->ptid)); | |
3819 | /* The Linux kernel sometimes fails to kill a thread | |
3820 | completely after PTRACE_KILL; that goes from the stop | |
3821 | point in do_fork out to the one in | |
3822 | get_signal_to_deliever and waits again. So kill it | |
3823 | again. */ | |
3824 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3825 | } |
3826 | } | |
dfd4cc63 | 3827 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3828 | |
3829 | gdb_assert (pid == -1 && errno == ECHILD); | |
3830 | } | |
3831 | ||
3832 | do | |
3833 | { | |
dfd4cc63 | 3834 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3835 | if (pid != (pid_t) -1) |
d6b0e80f | 3836 | { |
e85a822c DJ |
3837 | if (debug_linux_nat) |
3838 | fprintf_unfiltered (gdb_stdlog, | |
3839 | "KWC: wait %s received unk.\n", | |
3840 | target_pid_to_str (lp->ptid)); | |
3841 | /* See the call to kill_callback above. */ | |
3842 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3843 | } |
3844 | } | |
dfd4cc63 | 3845 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3846 | |
3847 | gdb_assert (pid == -1 && errno == ECHILD); | |
3848 | return 0; | |
3849 | } | |
3850 | ||
3851 | static void | |
7d85a9c0 | 3852 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3853 | { |
f973ed9c DJ |
3854 | struct target_waitstatus last; |
3855 | ptid_t last_ptid; | |
3856 | int status; | |
d6b0e80f | 3857 | |
f973ed9c DJ |
3858 | /* If we're stopped while forking and we haven't followed yet, |
3859 | kill the other task. We need to do this first because the | |
3860 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3861 | |
f973ed9c | 3862 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3863 | |
f973ed9c DJ |
3864 | if (last.kind == TARGET_WAITKIND_FORKED |
3865 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3866 | { | |
dfd4cc63 | 3867 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3868 | wait (&status); |
26cb8b7c PA |
3869 | |
3870 | /* Let the arch-specific native code know this process is | |
3871 | gone. */ | |
dfd4cc63 | 3872 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3873 | } |
3874 | ||
3875 | if (forks_exist_p ()) | |
7feb7d06 | 3876 | linux_fork_killall (); |
f973ed9c DJ |
3877 | else |
3878 | { | |
d90e17a7 | 3879 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3880 | |
4c28f408 PA |
3881 | /* Stop all threads before killing them, since ptrace requires |
3882 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3883 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3884 | /* ... and wait until all of them have reported back that |
3885 | they're no longer running. */ | |
d90e17a7 | 3886 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3887 | |
f973ed9c | 3888 | /* Kill all LWP's ... */ |
d90e17a7 | 3889 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3890 | |
3891 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3892 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3893 | } |
3894 | ||
3895 | target_mourn_inferior (); | |
d6b0e80f AC |
3896 | } |
3897 | ||
3898 | static void | |
136d6dae | 3899 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3900 | { |
26cb8b7c PA |
3901 | int pid = ptid_get_pid (inferior_ptid); |
3902 | ||
3903 | purge_lwp_list (pid); | |
d6b0e80f | 3904 | |
f973ed9c | 3905 | if (! forks_exist_p ()) |
d90e17a7 PA |
3906 | /* Normal case, no other forks available. */ |
3907 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3908 | else |
3909 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3910 | there are other viable forks to debug. Delete the exiting | |
3911 | one and context-switch to the first available. */ | |
3912 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3913 | |
3914 | /* Let the arch-specific native code know this process is gone. */ | |
3915 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3916 | } |
3917 | ||
5b009018 PA |
3918 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3919 | layout of the inferiors' architecture. */ | |
3920 | ||
3921 | static void | |
a5362b9a | 3922 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3923 | { |
3924 | int done = 0; | |
3925 | ||
3926 | if (linux_nat_siginfo_fixup != NULL) | |
3927 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3928 | ||
3929 | /* If there was no callback, or the callback didn't do anything, | |
3930 | then just do a straight memcpy. */ | |
3931 | if (!done) | |
3932 | { | |
3933 | if (direction == 1) | |
a5362b9a | 3934 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3935 | else |
a5362b9a | 3936 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3937 | } |
3938 | } | |
3939 | ||
9b409511 | 3940 | static enum target_xfer_status |
4aa995e1 PA |
3941 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3942 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3943 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3944 | ULONGEST *xfered_len) | |
4aa995e1 | 3945 | { |
4aa995e1 | 3946 | int pid; |
a5362b9a TS |
3947 | siginfo_t siginfo; |
3948 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3949 | |
3950 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3951 | gdb_assert (readbuf || writebuf); | |
3952 | ||
dfd4cc63 | 3953 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3954 | if (pid == 0) |
dfd4cc63 | 3955 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3956 | |
3957 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3958 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3959 | |
3960 | errno = 0; | |
3961 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3962 | if (errno != 0) | |
2ed4b548 | 3963 | return TARGET_XFER_E_IO; |
4aa995e1 | 3964 | |
5b009018 PA |
3965 | /* When GDB is built as a 64-bit application, ptrace writes into |
3966 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3967 | inferior with a 64-bit GDB should look the same as debugging it | |
3968 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3969 | the converted layout, so any read/write will have to be done | |
3970 | post-conversion. */ | |
3971 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3972 | ||
4aa995e1 PA |
3973 | if (offset + len > sizeof (siginfo)) |
3974 | len = sizeof (siginfo) - offset; | |
3975 | ||
3976 | if (readbuf != NULL) | |
5b009018 | 3977 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3978 | else |
3979 | { | |
5b009018 PA |
3980 | memcpy (inf_siginfo + offset, writebuf, len); |
3981 | ||
3982 | /* Convert back to ptrace layout before flushing it out. */ | |
3983 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3984 | ||
4aa995e1 PA |
3985 | errno = 0; |
3986 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3987 | if (errno != 0) | |
2ed4b548 | 3988 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3989 | } |
3990 | ||
9b409511 YQ |
3991 | *xfered_len = len; |
3992 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3993 | } |
3994 | ||
9b409511 | 3995 | static enum target_xfer_status |
10d6c8cd DJ |
3996 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3997 | const char *annex, gdb_byte *readbuf, | |
3998 | const gdb_byte *writebuf, | |
9b409511 | 3999 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 4000 | { |
4aa995e1 | 4001 | struct cleanup *old_chain; |
9b409511 | 4002 | enum target_xfer_status xfer; |
d6b0e80f | 4003 | |
4aa995e1 PA |
4004 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
4005 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4006 | offset, len, xfered_len); |
4aa995e1 | 4007 | |
c35b1492 PA |
4008 | /* The target is connected but no live inferior is selected. Pass |
4009 | this request down to a lower stratum (e.g., the executable | |
4010 | file). */ | |
4011 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 4012 | return TARGET_XFER_EOF; |
c35b1492 | 4013 | |
4aa995e1 PA |
4014 | old_chain = save_inferior_ptid (); |
4015 | ||
dfd4cc63 LM |
4016 | if (ptid_lwp_p (inferior_ptid)) |
4017 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 4018 | |
10d6c8cd | 4019 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 4020 | offset, len, xfered_len); |
d6b0e80f AC |
4021 | |
4022 | do_cleanups (old_chain); | |
4023 | return xfer; | |
4024 | } | |
4025 | ||
4026 | static int | |
28439f5e | 4027 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 4028 | { |
8c6a60d1 | 4029 | int err, tmp_errno; |
4c28f408 | 4030 | |
dfd4cc63 | 4031 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 4032 | |
4c28f408 PA |
4033 | /* Send signal 0 instead of anything ptrace, because ptracing a |
4034 | running thread errors out claiming that the thread doesn't | |
4035 | exist. */ | |
dfd4cc63 | 4036 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 4037 | tmp_errno = errno; |
d6b0e80f AC |
4038 | if (debug_linux_nat) |
4039 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 4040 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 4041 | target_pid_to_str (ptid), |
8c6a60d1 | 4042 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 4043 | |
4c28f408 | 4044 | if (err != 0) |
d6b0e80f AC |
4045 | return 0; |
4046 | ||
4047 | return 1; | |
4048 | } | |
4049 | ||
28439f5e PA |
4050 | static int |
4051 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
4052 | { | |
4053 | return linux_thread_alive (ptid); | |
4054 | } | |
4055 | ||
8a06aea7 PA |
4056 | /* Implement the to_update_thread_list target method for this |
4057 | target. */ | |
4058 | ||
4059 | static void | |
4060 | linux_nat_update_thread_list (struct target_ops *ops) | |
4061 | { | |
4062 | if (linux_supports_traceclone ()) | |
4063 | { | |
4064 | /* With support for clone events, we add/delete threads from the | |
4065 | list as clone/exit events are processed, so just try deleting | |
4066 | exited threads still in the thread list. */ | |
4067 | delete_exited_threads (); | |
4068 | } | |
4069 | else | |
4070 | prune_threads (); | |
4071 | } | |
4072 | ||
d6b0e80f | 4073 | static char * |
117de6a9 | 4074 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
4075 | { |
4076 | static char buf[64]; | |
4077 | ||
dfd4cc63 LM |
4078 | if (ptid_lwp_p (ptid) |
4079 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
4080 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 4081 | { |
dfd4cc63 | 4082 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
4083 | return buf; |
4084 | } | |
4085 | ||
4086 | return normal_pid_to_str (ptid); | |
4087 | } | |
4088 | ||
4694da01 | 4089 | static char * |
503a628d | 4090 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 TT |
4091 | { |
4092 | int pid = ptid_get_pid (thr->ptid); | |
4093 | long lwp = ptid_get_lwp (thr->ptid); | |
4094 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4095 | char buf[sizeof (FORMAT) + 30]; | |
4096 | FILE *comm_file; | |
4097 | char *result = NULL; | |
4098 | ||
4099 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4100 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4101 | if (comm_file) |
4102 | { | |
4103 | /* Not exported by the kernel, so we define it here. */ | |
4104 | #define COMM_LEN 16 | |
4105 | static char line[COMM_LEN + 1]; | |
4106 | ||
4107 | if (fgets (line, sizeof (line), comm_file)) | |
4108 | { | |
4109 | char *nl = strchr (line, '\n'); | |
4110 | ||
4111 | if (nl) | |
4112 | *nl = '\0'; | |
4113 | if (*line != '\0') | |
4114 | result = line; | |
4115 | } | |
4116 | ||
4117 | fclose (comm_file); | |
4118 | } | |
4119 | ||
4120 | #undef COMM_LEN | |
4121 | #undef FORMAT | |
4122 | ||
4123 | return result; | |
4124 | } | |
4125 | ||
dba24537 AC |
4126 | /* Accepts an integer PID; Returns a string representing a file that |
4127 | can be opened to get the symbols for the child process. */ | |
4128 | ||
6d8fd2b7 | 4129 | static char * |
8dd27370 | 4130 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 4131 | { |
e0d86d2c | 4132 | return linux_proc_pid_to_exec_file (pid); |
dba24537 AC |
4133 | } |
4134 | ||
10d6c8cd DJ |
4135 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4136 | filesystem. Because we can use a single read() call for /proc, this | |
4137 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4138 | but it doesn't support writes. */ | |
4139 | ||
9b409511 | 4140 | static enum target_xfer_status |
10d6c8cd DJ |
4141 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
4142 | const char *annex, gdb_byte *readbuf, | |
4143 | const gdb_byte *writebuf, | |
9b409511 | 4144 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 4145 | { |
10d6c8cd DJ |
4146 | LONGEST ret; |
4147 | int fd; | |
dba24537 AC |
4148 | char filename[64]; |
4149 | ||
10d6c8cd | 4150 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4151 | return 0; |
4152 | ||
4153 | /* Don't bother for one word. */ | |
4154 | if (len < 3 * sizeof (long)) | |
9b409511 | 4155 | return TARGET_XFER_EOF; |
dba24537 AC |
4156 | |
4157 | /* We could keep this file open and cache it - possibly one per | |
4158 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4159 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4160 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4161 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 4162 | if (fd == -1) |
9b409511 | 4163 | return TARGET_XFER_EOF; |
dba24537 AC |
4164 | |
4165 | /* If pread64 is available, use it. It's faster if the kernel | |
4166 | supports it (only one syscall), and it's 64-bit safe even on | |
4167 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4168 | application). */ | |
4169 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4170 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4171 | #else |
10d6c8cd | 4172 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4173 | #endif |
4174 | ret = 0; | |
4175 | else | |
4176 | ret = len; | |
4177 | ||
4178 | close (fd); | |
9b409511 YQ |
4179 | |
4180 | if (ret == 0) | |
4181 | return TARGET_XFER_EOF; | |
4182 | else | |
4183 | { | |
4184 | *xfered_len = ret; | |
4185 | return TARGET_XFER_OK; | |
4186 | } | |
dba24537 AC |
4187 | } |
4188 | ||
efcbbd14 UW |
4189 | |
4190 | /* Enumerate spufs IDs for process PID. */ | |
4191 | static LONGEST | |
b55e14c7 | 4192 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4193 | { |
f5656ead | 4194 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4195 | LONGEST pos = 0; |
4196 | LONGEST written = 0; | |
4197 | char path[128]; | |
4198 | DIR *dir; | |
4199 | struct dirent *entry; | |
4200 | ||
4201 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4202 | dir = opendir (path); | |
4203 | if (!dir) | |
4204 | return -1; | |
4205 | ||
4206 | rewinddir (dir); | |
4207 | while ((entry = readdir (dir)) != NULL) | |
4208 | { | |
4209 | struct stat st; | |
4210 | struct statfs stfs; | |
4211 | int fd; | |
4212 | ||
4213 | fd = atoi (entry->d_name); | |
4214 | if (!fd) | |
4215 | continue; | |
4216 | ||
4217 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4218 | if (stat (path, &st) != 0) | |
4219 | continue; | |
4220 | if (!S_ISDIR (st.st_mode)) | |
4221 | continue; | |
4222 | ||
4223 | if (statfs (path, &stfs) != 0) | |
4224 | continue; | |
4225 | if (stfs.f_type != SPUFS_MAGIC) | |
4226 | continue; | |
4227 | ||
4228 | if (pos >= offset && pos + 4 <= offset + len) | |
4229 | { | |
4230 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4231 | written += 4; | |
4232 | } | |
4233 | pos += 4; | |
4234 | } | |
4235 | ||
4236 | closedir (dir); | |
4237 | return written; | |
4238 | } | |
4239 | ||
4240 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4241 | object type, using the /proc file system. */ | |
9b409511 YQ |
4242 | |
4243 | static enum target_xfer_status | |
efcbbd14 UW |
4244 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4245 | const char *annex, gdb_byte *readbuf, | |
4246 | const gdb_byte *writebuf, | |
9b409511 | 4247 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4248 | { |
4249 | char buf[128]; | |
4250 | int fd = 0; | |
4251 | int ret = -1; | |
dfd4cc63 | 4252 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4253 | |
4254 | if (!annex) | |
4255 | { | |
4256 | if (!readbuf) | |
2ed4b548 | 4257 | return TARGET_XFER_E_IO; |
efcbbd14 | 4258 | else |
9b409511 YQ |
4259 | { |
4260 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4261 | ||
4262 | if (l < 0) | |
4263 | return TARGET_XFER_E_IO; | |
4264 | else if (l == 0) | |
4265 | return TARGET_XFER_EOF; | |
4266 | else | |
4267 | { | |
4268 | *xfered_len = (ULONGEST) l; | |
4269 | return TARGET_XFER_OK; | |
4270 | } | |
4271 | } | |
efcbbd14 UW |
4272 | } |
4273 | ||
4274 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4275 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4276 | if (fd <= 0) |
2ed4b548 | 4277 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4278 | |
4279 | if (offset != 0 | |
4280 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4281 | { | |
4282 | close (fd); | |
9b409511 | 4283 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4284 | } |
4285 | ||
4286 | if (writebuf) | |
4287 | ret = write (fd, writebuf, (size_t) len); | |
4288 | else if (readbuf) | |
4289 | ret = read (fd, readbuf, (size_t) len); | |
4290 | ||
4291 | close (fd); | |
9b409511 YQ |
4292 | |
4293 | if (ret < 0) | |
4294 | return TARGET_XFER_E_IO; | |
4295 | else if (ret == 0) | |
4296 | return TARGET_XFER_EOF; | |
4297 | else | |
4298 | { | |
4299 | *xfered_len = (ULONGEST) ret; | |
4300 | return TARGET_XFER_OK; | |
4301 | } | |
efcbbd14 UW |
4302 | } |
4303 | ||
4304 | ||
dba24537 AC |
4305 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4306 | ||
4307 | static void | |
4308 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4309 | { | |
4310 | int len = strlen (line) - 1; | |
4311 | const char *p; | |
4312 | int signum; | |
4313 | ||
4314 | if (line[len] != '\n') | |
8a3fe4f8 | 4315 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4316 | |
4317 | p = line; | |
4318 | signum = len * 4; | |
4319 | while (len-- > 0) | |
4320 | { | |
4321 | int digit; | |
4322 | ||
4323 | if (*p >= '0' && *p <= '9') | |
4324 | digit = *p - '0'; | |
4325 | else if (*p >= 'a' && *p <= 'f') | |
4326 | digit = *p - 'a' + 10; | |
4327 | else | |
8a3fe4f8 | 4328 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4329 | |
4330 | signum -= 4; | |
4331 | ||
4332 | if (digit & 1) | |
4333 | sigaddset (sigs, signum + 1); | |
4334 | if (digit & 2) | |
4335 | sigaddset (sigs, signum + 2); | |
4336 | if (digit & 4) | |
4337 | sigaddset (sigs, signum + 3); | |
4338 | if (digit & 8) | |
4339 | sigaddset (sigs, signum + 4); | |
4340 | ||
4341 | p++; | |
4342 | } | |
4343 | } | |
4344 | ||
4345 | /* Find process PID's pending signals from /proc/pid/status and set | |
4346 | SIGS to match. */ | |
4347 | ||
4348 | void | |
3e43a32a MS |
4349 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4350 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4351 | { |
4352 | FILE *procfile; | |
d8d2a3ee | 4353 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4354 | struct cleanup *cleanup; |
dba24537 AC |
4355 | |
4356 | sigemptyset (pending); | |
4357 | sigemptyset (blocked); | |
4358 | sigemptyset (ignored); | |
cde33bf1 | 4359 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4360 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4361 | if (procfile == NULL) |
8a3fe4f8 | 4362 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4363 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4364 | |
d8d2a3ee | 4365 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4366 | { |
4367 | /* Normal queued signals are on the SigPnd line in the status | |
4368 | file. However, 2.6 kernels also have a "shared" pending | |
4369 | queue for delivering signals to a thread group, so check for | |
4370 | a ShdPnd line also. | |
4371 | ||
4372 | Unfortunately some Red Hat kernels include the shared pending | |
4373 | queue but not the ShdPnd status field. */ | |
4374 | ||
61012eef | 4375 | if (startswith (buffer, "SigPnd:\t")) |
dba24537 | 4376 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4377 | else if (startswith (buffer, "ShdPnd:\t")) |
dba24537 | 4378 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4379 | else if (startswith (buffer, "SigBlk:\t")) |
dba24537 | 4380 | add_line_to_sigset (buffer + 8, blocked); |
61012eef | 4381 | else if (startswith (buffer, "SigIgn:\t")) |
dba24537 AC |
4382 | add_line_to_sigset (buffer + 8, ignored); |
4383 | } | |
4384 | ||
7c8a8b04 | 4385 | do_cleanups (cleanup); |
dba24537 AC |
4386 | } |
4387 | ||
9b409511 | 4388 | static enum target_xfer_status |
07e059b5 | 4389 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4390 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4391 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4392 | ULONGEST *xfered_len) | |
07e059b5 | 4393 | { |
07e059b5 VP |
4394 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4395 | ||
9b409511 YQ |
4396 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4397 | if (*xfered_len == 0) | |
4398 | return TARGET_XFER_EOF; | |
4399 | else | |
4400 | return TARGET_XFER_OK; | |
07e059b5 VP |
4401 | } |
4402 | ||
9b409511 | 4403 | static enum target_xfer_status |
10d6c8cd DJ |
4404 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4405 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4406 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4407 | ULONGEST *xfered_len) | |
10d6c8cd | 4408 | { |
9b409511 | 4409 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4410 | |
4411 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4412 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4413 | offset, len, xfered_len); |
10d6c8cd | 4414 | |
07e059b5 VP |
4415 | if (object == TARGET_OBJECT_OSDATA) |
4416 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4417 | offset, len, xfered_len); |
07e059b5 | 4418 | |
efcbbd14 UW |
4419 | if (object == TARGET_OBJECT_SPU) |
4420 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4421 | offset, len, xfered_len); |
efcbbd14 | 4422 | |
8f313923 JK |
4423 | /* GDB calculates all the addresses in possibly larget width of the address. |
4424 | Address width needs to be masked before its final use - either by | |
4425 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4426 | ||
4427 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4428 | ||
4429 | if (object == TARGET_OBJECT_MEMORY) | |
4430 | { | |
f5656ead | 4431 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4432 | |
4433 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4434 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4435 | } | |
4436 | ||
10d6c8cd | 4437 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4438 | offset, len, xfered_len); |
4439 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4440 | return xfer; |
4441 | ||
4442 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4443 | offset, len, xfered_len); |
10d6c8cd DJ |
4444 | } |
4445 | ||
5808517f YQ |
4446 | static void |
4447 | cleanup_target_stop (void *arg) | |
4448 | { | |
4449 | ptid_t *ptid = (ptid_t *) arg; | |
4450 | ||
4451 | gdb_assert (arg != NULL); | |
4452 | ||
4453 | /* Unpause all */ | |
a493e3e2 | 4454 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4455 | } |
4456 | ||
4457 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4458 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4459 | const char *strid) | |
5808517f YQ |
4460 | { |
4461 | char s[IPA_CMD_BUF_SIZE]; | |
4462 | struct cleanup *old_chain; | |
4463 | int pid = ptid_get_pid (inferior_ptid); | |
4464 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4465 | struct static_tracepoint_marker *marker = NULL; | |
4466 | char *p = s; | |
4467 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4468 | ||
4469 | /* Pause all */ | |
4470 | target_stop (ptid); | |
4471 | ||
4472 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4473 | s[sizeof ("qTfSTM")] = 0; | |
4474 | ||
42476b70 | 4475 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4476 | |
4477 | old_chain = make_cleanup (free_current_marker, &marker); | |
4478 | make_cleanup (cleanup_target_stop, &ptid); | |
4479 | ||
4480 | while (*p++ == 'm') | |
4481 | { | |
4482 | if (marker == NULL) | |
4483 | marker = XCNEW (struct static_tracepoint_marker); | |
4484 | ||
4485 | do | |
4486 | { | |
4487 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4488 | ||
4489 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4490 | { | |
4491 | VEC_safe_push (static_tracepoint_marker_p, | |
4492 | markers, marker); | |
4493 | marker = NULL; | |
4494 | } | |
4495 | else | |
4496 | { | |
4497 | release_static_tracepoint_marker (marker); | |
4498 | memset (marker, 0, sizeof (*marker)); | |
4499 | } | |
4500 | } | |
4501 | while (*p++ == ','); /* comma-separated list */ | |
4502 | ||
4503 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4504 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4505 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4506 | p = s; |
4507 | } | |
4508 | ||
4509 | do_cleanups (old_chain); | |
4510 | ||
4511 | return markers; | |
4512 | } | |
4513 | ||
e9efe249 | 4514 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4515 | it with local methods. */ |
4516 | ||
910122bf UW |
4517 | static void |
4518 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4519 | { |
6d8fd2b7 | 4520 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4521 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4522 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4523 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4524 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4525 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4526 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4527 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4528 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4529 | t->to_post_attach = linux_child_post_attach; |
4530 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4531 | |
4532 | super_xfer_partial = t->to_xfer_partial; | |
4533 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4534 | |
4535 | t->to_static_tracepoint_markers_by_strid | |
4536 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4537 | } |
4538 | ||
4539 | struct target_ops * | |
4540 | linux_target (void) | |
4541 | { | |
4542 | struct target_ops *t; | |
4543 | ||
4544 | t = inf_ptrace_target (); | |
4545 | linux_target_install_ops (t); | |
4546 | ||
4547 | return t; | |
4548 | } | |
4549 | ||
4550 | struct target_ops * | |
7714d83a | 4551 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4552 | { |
4553 | struct target_ops *t; | |
4554 | ||
4555 | t = inf_ptrace_trad_target (register_u_offset); | |
4556 | linux_target_install_ops (t); | |
10d6c8cd | 4557 | |
10d6c8cd DJ |
4558 | return t; |
4559 | } | |
4560 | ||
b84876c2 PA |
4561 | /* target_is_async_p implementation. */ |
4562 | ||
4563 | static int | |
6a109b6b | 4564 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 | 4565 | { |
198297aa | 4566 | return linux_is_async_p (); |
b84876c2 PA |
4567 | } |
4568 | ||
4569 | /* target_can_async_p implementation. */ | |
4570 | ||
4571 | static int | |
6a109b6b | 4572 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4573 | { |
4574 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4575 | it explicitly with the "set target-async" command. |
b84876c2 | 4576 | Someday, linux will always be async. */ |
3dd5b83d | 4577 | return target_async_permitted; |
b84876c2 PA |
4578 | } |
4579 | ||
9908b566 | 4580 | static int |
2a9a2795 | 4581 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4582 | { |
4583 | return 1; | |
4584 | } | |
4585 | ||
d90e17a7 PA |
4586 | /* True if we want to support multi-process. To be removed when GDB |
4587 | supports multi-exec. */ | |
4588 | ||
2277426b | 4589 | int linux_multi_process = 1; |
d90e17a7 PA |
4590 | |
4591 | static int | |
86ce2668 | 4592 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4593 | { |
4594 | return linux_multi_process; | |
4595 | } | |
4596 | ||
03583c20 | 4597 | static int |
2bfc0540 | 4598 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4599 | { |
4600 | #ifdef HAVE_PERSONALITY | |
4601 | return 1; | |
4602 | #else | |
4603 | return 0; | |
4604 | #endif | |
4605 | } | |
4606 | ||
b84876c2 PA |
4607 | static int async_terminal_is_ours = 1; |
4608 | ||
4d4ca2a1 DE |
4609 | /* target_terminal_inferior implementation. |
4610 | ||
4611 | This is a wrapper around child_terminal_inferior to add async support. */ | |
b84876c2 PA |
4612 | |
4613 | static void | |
d2f640d4 | 4614 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 | 4615 | { |
198297aa PA |
4616 | /* Like target_terminal_inferior, use target_can_async_p, not |
4617 | target_is_async_p, since at this point the target is not async | |
4618 | yet. If it can async, then we know it will become async prior to | |
4619 | resume. */ | |
4620 | if (!target_can_async_p ()) | |
b84876c2 PA |
4621 | { |
4622 | /* Async mode is disabled. */ | |
d6b64346 | 4623 | child_terminal_inferior (self); |
b84876c2 PA |
4624 | return; |
4625 | } | |
4626 | ||
d6b64346 | 4627 | child_terminal_inferior (self); |
b84876c2 | 4628 | |
d9d2d8b6 | 4629 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4630 | if (!async_terminal_is_ours) |
4631 | return; | |
4632 | ||
4633 | delete_file_handler (input_fd); | |
4634 | async_terminal_is_ours = 0; | |
4635 | set_sigint_trap (); | |
4636 | } | |
4637 | ||
4d4ca2a1 DE |
4638 | /* target_terminal_ours implementation. |
4639 | ||
4640 | This is a wrapper around child_terminal_ours to add async support (and | |
4641 | implement the target_terminal_ours vs target_terminal_ours_for_output | |
4642 | distinction). child_terminal_ours is currently no different than | |
4643 | child_terminal_ours_for_output. | |
4644 | We leave target_terminal_ours_for_output alone, leaving it to | |
4645 | child_terminal_ours_for_output. */ | |
b84876c2 | 4646 | |
2c0b251b | 4647 | static void |
e3594fd1 | 4648 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 | 4649 | { |
b84876c2 PA |
4650 | /* GDB should never give the terminal to the inferior if the |
4651 | inferior is running in the background (run&, continue&, etc.), | |
4652 | but claiming it sure should. */ | |
d6b64346 | 4653 | child_terminal_ours (self); |
b84876c2 | 4654 | |
b84876c2 PA |
4655 | if (async_terminal_is_ours) |
4656 | return; | |
4657 | ||
4658 | clear_sigint_trap (); | |
4659 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4660 | async_terminal_is_ours = 1; | |
4661 | } | |
4662 | ||
7feb7d06 PA |
4663 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4664 | so we notice when any child changes state, and notify the | |
4665 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4666 | above to wait for the arrival of a SIGCHLD. */ | |
4667 | ||
b84876c2 | 4668 | static void |
7feb7d06 | 4669 | sigchld_handler (int signo) |
b84876c2 | 4670 | { |
7feb7d06 PA |
4671 | int old_errno = errno; |
4672 | ||
01124a23 DE |
4673 | if (debug_linux_nat) |
4674 | ui_file_write_async_safe (gdb_stdlog, | |
4675 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4676 | |
4677 | if (signo == SIGCHLD | |
4678 | && linux_nat_event_pipe[0] != -1) | |
4679 | async_file_mark (); /* Let the event loop know that there are | |
4680 | events to handle. */ | |
4681 | ||
4682 | errno = old_errno; | |
4683 | } | |
4684 | ||
4685 | /* Callback registered with the target events file descriptor. */ | |
4686 | ||
4687 | static void | |
4688 | handle_target_event (int error, gdb_client_data client_data) | |
4689 | { | |
6a3753b3 | 4690 | inferior_event_handler (INF_REG_EVENT, NULL); |
7feb7d06 PA |
4691 | } |
4692 | ||
4693 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4694 | ||
4695 | static int | |
4696 | linux_async_pipe (int enable) | |
4697 | { | |
198297aa | 4698 | int previous = linux_is_async_p (); |
7feb7d06 PA |
4699 | |
4700 | if (previous != enable) | |
4701 | { | |
4702 | sigset_t prev_mask; | |
4703 | ||
12696c10 PA |
4704 | /* Block child signals while we create/destroy the pipe, as |
4705 | their handler writes to it. */ | |
7feb7d06 PA |
4706 | block_child_signals (&prev_mask); |
4707 | ||
4708 | if (enable) | |
4709 | { | |
614c279d | 4710 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4711 | internal_error (__FILE__, __LINE__, |
4712 | "creating event pipe failed."); | |
4713 | ||
4714 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4715 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4716 | } | |
4717 | else | |
4718 | { | |
4719 | close (linux_nat_event_pipe[0]); | |
4720 | close (linux_nat_event_pipe[1]); | |
4721 | linux_nat_event_pipe[0] = -1; | |
4722 | linux_nat_event_pipe[1] = -1; | |
4723 | } | |
4724 | ||
4725 | restore_child_signals_mask (&prev_mask); | |
4726 | } | |
4727 | ||
4728 | return previous; | |
b84876c2 PA |
4729 | } |
4730 | ||
4731 | /* target_async implementation. */ | |
4732 | ||
4733 | static void | |
6a3753b3 | 4734 | linux_nat_async (struct target_ops *ops, int enable) |
b84876c2 | 4735 | { |
6a3753b3 | 4736 | if (enable) |
b84876c2 | 4737 | { |
7feb7d06 PA |
4738 | if (!linux_async_pipe (1)) |
4739 | { | |
4740 | add_file_handler (linux_nat_event_pipe[0], | |
4741 | handle_target_event, NULL); | |
4742 | /* There may be pending events to handle. Tell the event loop | |
4743 | to poll them. */ | |
4744 | async_file_mark (); | |
4745 | } | |
b84876c2 PA |
4746 | } |
4747 | else | |
4748 | { | |
b84876c2 | 4749 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4750 | linux_async_pipe (0); |
b84876c2 PA |
4751 | } |
4752 | return; | |
4753 | } | |
4754 | ||
a493e3e2 | 4755 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4756 | event came out. */ |
4757 | ||
4c28f408 | 4758 | static int |
252fbfc8 | 4759 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4760 | { |
d90e17a7 | 4761 | if (!lwp->stopped) |
252fbfc8 | 4762 | { |
d90e17a7 PA |
4763 | if (debug_linux_nat) |
4764 | fprintf_unfiltered (gdb_stdlog, | |
4765 | "LNSL: running -> suspending %s\n", | |
4766 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4767 | |
252fbfc8 | 4768 | |
25289eb2 PA |
4769 | if (lwp->last_resume_kind == resume_stop) |
4770 | { | |
4771 | if (debug_linux_nat) | |
4772 | fprintf_unfiltered (gdb_stdlog, | |
4773 | "linux-nat: already stopping LWP %ld at " | |
4774 | "GDB's request\n", | |
4775 | ptid_get_lwp (lwp->ptid)); | |
4776 | return 0; | |
4777 | } | |
252fbfc8 | 4778 | |
25289eb2 PA |
4779 | stop_callback (lwp, NULL); |
4780 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4781 | } |
4782 | else | |
4783 | { | |
4784 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4785 | |
d90e17a7 PA |
4786 | if (debug_linux_nat) |
4787 | { | |
e09875d4 | 4788 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4789 | fprintf_unfiltered (gdb_stdlog, |
4790 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4791 | target_pid_to_str (lwp->ptid)); |
4792 | else | |
3e43a32a MS |
4793 | fprintf_unfiltered (gdb_stdlog, |
4794 | "LNSL: already stopped/no " | |
4795 | "stop_requested yet %s\n", | |
d90e17a7 | 4796 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4797 | } |
4798 | } | |
4c28f408 PA |
4799 | return 0; |
4800 | } | |
4801 | ||
4802 | static void | |
1eab8a48 | 4803 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 PA |
4804 | { |
4805 | if (non_stop) | |
d90e17a7 | 4806 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4807 | else |
1eab8a48 | 4808 | linux_ops->to_stop (linux_ops, ptid); |
4c28f408 PA |
4809 | } |
4810 | ||
d90e17a7 | 4811 | static void |
de90e03d | 4812 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4813 | { |
4814 | /* Unregister from the event loop. */ | |
9debeba0 | 4815 | if (linux_nat_is_async_p (self)) |
6a3753b3 | 4816 | linux_nat_async (self, 0); |
d90e17a7 | 4817 | |
d90e17a7 | 4818 | if (linux_ops->to_close) |
de90e03d | 4819 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4820 | |
4821 | super_close (self); | |
d90e17a7 PA |
4822 | } |
4823 | ||
c0694254 PA |
4824 | /* When requests are passed down from the linux-nat layer to the |
4825 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4826 | used. The address space pointer is stored in the inferior object, | |
4827 | but the common code that is passed such ptid can't tell whether | |
4828 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4829 | look up the "main" process id from the lwp here. */ | |
4830 | ||
70221824 | 4831 | static struct address_space * |
c0694254 PA |
4832 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4833 | { | |
4834 | struct lwp_info *lwp; | |
4835 | struct inferior *inf; | |
4836 | int pid; | |
4837 | ||
dfd4cc63 | 4838 | if (ptid_get_lwp (ptid) == 0) |
c0694254 PA |
4839 | { |
4840 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4841 | tgid. */ | |
4842 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4843 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4844 | } |
4845 | else | |
4846 | { | |
4847 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4848 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4849 | } |
4850 | ||
4851 | inf = find_inferior_pid (pid); | |
4852 | gdb_assert (inf != NULL); | |
4853 | return inf->aspace; | |
4854 | } | |
4855 | ||
dc146f7c VP |
4856 | /* Return the cached value of the processor core for thread PTID. */ |
4857 | ||
70221824 | 4858 | static int |
dc146f7c VP |
4859 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4860 | { | |
4861 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4862 | |
dc146f7c VP |
4863 | if (info) |
4864 | return info->core; | |
4865 | return -1; | |
4866 | } | |
4867 | ||
f973ed9c DJ |
4868 | void |
4869 | linux_nat_add_target (struct target_ops *t) | |
4870 | { | |
f973ed9c DJ |
4871 | /* Save the provided single-threaded target. We save this in a separate |
4872 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4873 | may have saved a pointer to T; we want to use it for the final | |
4874 | process stratum target. */ | |
4875 | linux_ops_saved = *t; | |
4876 | linux_ops = &linux_ops_saved; | |
4877 | ||
4878 | /* Override some methods for multithreading. */ | |
b84876c2 | 4879 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4880 | t->to_attach = linux_nat_attach; |
4881 | t->to_detach = linux_nat_detach; | |
4882 | t->to_resume = linux_nat_resume; | |
4883 | t->to_wait = linux_nat_wait; | |
2455069d | 4884 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4885 | t->to_xfer_partial = linux_nat_xfer_partial; |
4886 | t->to_kill = linux_nat_kill; | |
4887 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4888 | t->to_thread_alive = linux_nat_thread_alive; | |
8a06aea7 | 4889 | t->to_update_thread_list = linux_nat_update_thread_list; |
f973ed9c | 4890 | t->to_pid_to_str = linux_nat_pid_to_str; |
4694da01 | 4891 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4892 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4893 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4894 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4895 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
faf09f01 PA |
4896 | t->to_stopped_by_sw_breakpoint = linux_nat_stopped_by_sw_breakpoint; |
4897 | t->to_supports_stopped_by_sw_breakpoint = linux_nat_supports_stopped_by_sw_breakpoint; | |
4898 | t->to_stopped_by_hw_breakpoint = linux_nat_stopped_by_hw_breakpoint; | |
4899 | t->to_supports_stopped_by_hw_breakpoint = linux_nat_supports_stopped_by_hw_breakpoint; | |
f973ed9c | 4900 | |
b84876c2 PA |
4901 | t->to_can_async_p = linux_nat_can_async_p; |
4902 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4903 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4904 | t->to_async = linux_nat_async; |
b84876c2 PA |
4905 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4906 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4907 | |
4908 | super_close = t->to_close; | |
d90e17a7 | 4909 | t->to_close = linux_nat_close; |
b84876c2 | 4910 | |
4c28f408 PA |
4911 | /* Methods for non-stop support. */ |
4912 | t->to_stop = linux_nat_stop; | |
4913 | ||
d90e17a7 PA |
4914 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4915 | ||
03583c20 UW |
4916 | t->to_supports_disable_randomization |
4917 | = linux_nat_supports_disable_randomization; | |
4918 | ||
dc146f7c VP |
4919 | t->to_core_of_thread = linux_nat_core_of_thread; |
4920 | ||
f973ed9c DJ |
4921 | /* We don't change the stratum; this target will sit at |
4922 | process_stratum and thread_db will set at thread_stratum. This | |
4923 | is a little strange, since this is a multi-threaded-capable | |
4924 | target, but we want to be on the stack below thread_db, and we | |
4925 | also want to be used for single-threaded processes. */ | |
4926 | ||
4927 | add_target (t); | |
f973ed9c DJ |
4928 | } |
4929 | ||
9f0bdab8 DJ |
4930 | /* Register a method to call whenever a new thread is attached. */ |
4931 | void | |
7b50312a PA |
4932 | linux_nat_set_new_thread (struct target_ops *t, |
4933 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4934 | { |
4935 | /* Save the pointer. We only support a single registered instance | |
4936 | of the GNU/Linux native target, so we do not need to map this to | |
4937 | T. */ | |
4938 | linux_nat_new_thread = new_thread; | |
4939 | } | |
4940 | ||
26cb8b7c PA |
4941 | /* See declaration in linux-nat.h. */ |
4942 | ||
4943 | void | |
4944 | linux_nat_set_new_fork (struct target_ops *t, | |
4945 | linux_nat_new_fork_ftype *new_fork) | |
4946 | { | |
4947 | /* Save the pointer. */ | |
4948 | linux_nat_new_fork = new_fork; | |
4949 | } | |
4950 | ||
4951 | /* See declaration in linux-nat.h. */ | |
4952 | ||
4953 | void | |
4954 | linux_nat_set_forget_process (struct target_ops *t, | |
4955 | linux_nat_forget_process_ftype *fn) | |
4956 | { | |
4957 | /* Save the pointer. */ | |
4958 | linux_nat_forget_process_hook = fn; | |
4959 | } | |
4960 | ||
4961 | /* See declaration in linux-nat.h. */ | |
4962 | ||
4963 | void | |
4964 | linux_nat_forget_process (pid_t pid) | |
4965 | { | |
4966 | if (linux_nat_forget_process_hook != NULL) | |
4967 | linux_nat_forget_process_hook (pid); | |
4968 | } | |
4969 | ||
5b009018 PA |
4970 | /* Register a method that converts a siginfo object between the layout |
4971 | that ptrace returns, and the layout in the architecture of the | |
4972 | inferior. */ | |
4973 | void | |
4974 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4975 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4976 | gdb_byte *, |
4977 | int)) | |
4978 | { | |
4979 | /* Save the pointer. */ | |
4980 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4981 | } | |
4982 | ||
7b50312a PA |
4983 | /* Register a method to call prior to resuming a thread. */ |
4984 | ||
4985 | void | |
4986 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4987 | void (*prepare_to_resume) (struct lwp_info *)) | |
4988 | { | |
4989 | /* Save the pointer. */ | |
4990 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4991 | } | |
4992 | ||
f865ee35 JK |
4993 | /* See linux-nat.h. */ |
4994 | ||
4995 | int | |
4996 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4997 | { |
da559b09 | 4998 | int pid; |
9f0bdab8 | 4999 | |
dfd4cc63 | 5000 | pid = ptid_get_lwp (ptid); |
da559b09 | 5001 | if (pid == 0) |
dfd4cc63 | 5002 | pid = ptid_get_pid (ptid); |
f865ee35 | 5003 | |
da559b09 JK |
5004 | errno = 0; |
5005 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
5006 | if (errno != 0) | |
5007 | { | |
5008 | memset (siginfo, 0, sizeof (*siginfo)); | |
5009 | return 0; | |
5010 | } | |
f865ee35 | 5011 | return 1; |
9f0bdab8 DJ |
5012 | } |
5013 | ||
7b669087 GB |
5014 | /* See nat/linux-nat.h. */ |
5015 | ||
5016 | ptid_t | |
5017 | current_lwp_ptid (void) | |
5018 | { | |
5019 | gdb_assert (ptid_lwp_p (inferior_ptid)); | |
5020 | return inferior_ptid; | |
5021 | } | |
5022 | ||
2c0b251b PA |
5023 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
5024 | extern initialize_file_ftype _initialize_linux_nat; | |
5025 | ||
d6b0e80f AC |
5026 | void |
5027 | _initialize_linux_nat (void) | |
5028 | { | |
ccce17b0 YQ |
5029 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
5030 | &debug_linux_nat, _("\ | |
b84876c2 PA |
5031 | Set debugging of GNU/Linux lwp module."), _("\ |
5032 | Show debugging of GNU/Linux lwp module."), _("\ | |
5033 | Enables printf debugging output."), | |
ccce17b0 YQ |
5034 | NULL, |
5035 | show_debug_linux_nat, | |
5036 | &setdebuglist, &showdebuglist); | |
b84876c2 | 5037 | |
b84876c2 | 5038 | /* Save this mask as the default. */ |
d6b0e80f AC |
5039 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
5040 | ||
7feb7d06 PA |
5041 | /* Install a SIGCHLD handler. */ |
5042 | sigchld_action.sa_handler = sigchld_handler; | |
5043 | sigemptyset (&sigchld_action.sa_mask); | |
5044 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
5045 | |
5046 | /* Make it the default. */ | |
7feb7d06 | 5047 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5048 | |
5049 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5050 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5051 | sigdelset (&suspend_mask, SIGCHLD); | |
5052 | ||
7feb7d06 | 5053 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5054 | } |
5055 | \f | |
5056 | ||
5057 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5058 | the GNU/Linux Threads library and therefore doesn't really belong | |
5059 | here. */ | |
5060 | ||
5061 | /* Read variable NAME in the target and return its value if found. | |
5062 | Otherwise return zero. It is assumed that the type of the variable | |
5063 | is `int'. */ | |
5064 | ||
5065 | static int | |
5066 | get_signo (const char *name) | |
5067 | { | |
3b7344d5 | 5068 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5069 | int signo; |
5070 | ||
5071 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5072 | if (ms.minsym == NULL) |
d6b0e80f AC |
5073 | return 0; |
5074 | ||
77e371c0 | 5075 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5076 | sizeof (signo)) != 0) |
5077 | return 0; | |
5078 | ||
5079 | return signo; | |
5080 | } | |
5081 | ||
5082 | /* Return the set of signals used by the threads library in *SET. */ | |
5083 | ||
5084 | void | |
5085 | lin_thread_get_thread_signals (sigset_t *set) | |
5086 | { | |
5087 | struct sigaction action; | |
5088 | int restart, cancel; | |
5089 | ||
b84876c2 | 5090 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5091 | sigemptyset (set); |
5092 | ||
5093 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5094 | cancel = get_signo ("__pthread_sig_cancel"); |
5095 | ||
5096 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5097 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5098 | not provide any way for the debugger to query the signal numbers - | |
5099 | fortunately they don't change! */ | |
5100 | ||
d6b0e80f | 5101 | if (restart == 0) |
17fbb0bd | 5102 | restart = __SIGRTMIN; |
d6b0e80f | 5103 | |
d6b0e80f | 5104 | if (cancel == 0) |
17fbb0bd | 5105 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5106 | |
5107 | sigaddset (set, restart); | |
5108 | sigaddset (set, cancel); | |
5109 | ||
5110 | /* The GNU/Linux Threads library makes terminating threads send a | |
5111 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5112 | those (to prevent them from terminating GDB itself, which is | |
5113 | likely to be their default action) and treat them the same way as | |
5114 | SIGCHLD. */ | |
5115 | ||
5116 | action.sa_handler = sigchld_handler; | |
5117 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5118 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5119 | sigaction (cancel, &action, NULL); |
5120 | ||
5121 | /* We block the "cancel" signal throughout this code ... */ | |
5122 | sigaddset (&blocked_mask, cancel); | |
5123 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5124 | ||
5125 | /* ... except during a sigsuspend. */ | |
5126 | sigdelset (&suspend_mask, cancel); | |
5127 | } |