Commit | Line | Data |
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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 | |
5826e159 | 31 | #include "nat/gdb_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" |
7a6a1731 GB |
69 | #include "nat/linux-namespaces.h" |
70 | #include "fileio.h" | |
efcbbd14 UW |
71 | |
72 | #ifndef SPUFS_MAGIC | |
73 | #define SPUFS_MAGIC 0x23c9b64e | |
74 | #endif | |
dba24537 | 75 | |
1777feb0 | 76 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
77 | |
78 | Waiting for events in sync mode | |
79 | =============================== | |
80 | ||
81 | When waiting for an event in a specific thread, we just use waitpid, passing | |
82 | the specific pid, and not passing WNOHANG. | |
83 | ||
1777feb0 | 84 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 85 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 86 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
87 | miss an event. The solution is to use non-blocking waitpid, together with |
88 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 89 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
90 | flag to check for events in cloned processes. If nothing is found, we use |
91 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
92 | happened to a child process -- and SIGCHLD will be delivered both for events | |
93 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
94 | an event, we get back to calling nonblocking waitpid with and without |
95 | __WCLONED. | |
8a77dff3 VP |
96 | |
97 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 98 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
99 | blocked, the signal becomes pending and sigsuspend immediately |
100 | notices it and returns. | |
101 | ||
102 | Waiting for events in async mode | |
103 | ================================ | |
104 | ||
7feb7d06 PA |
105 | In async mode, GDB should always be ready to handle both user input |
106 | and target events, so neither blocking waitpid nor sigsuspend are | |
107 | viable options. Instead, we should asynchronously notify the GDB main | |
108 | event loop whenever there's an unprocessed event from the target. We | |
109 | detect asynchronous target events by handling SIGCHLD signals. To | |
110 | notify the event loop about target events, the self-pipe trick is used | |
111 | --- a pipe is registered as waitable event source in the event loop, | |
112 | the event loop select/poll's on the read end of this pipe (as well on | |
113 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
114 | byte to this pipe. This is more portable than relying on | |
115 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
116 | emulates them with select/poll+sigprocmask, and that is racy | |
117 | (a.k.a. plain broken). | |
118 | ||
119 | Obviously, if we fail to notify the event loop if there's a target | |
120 | event, it's bad. OTOH, if we notify the event loop when there's no | |
121 | event from the target, linux_nat_wait will detect that there's no real | |
122 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
123 | This is mostly harmless, but it will waste time and is better avoided. | |
124 | ||
125 | The main design point is that every time GDB is outside linux-nat.c, | |
126 | we have a SIGCHLD handler installed that is called when something | |
127 | happens to the target and notifies the GDB event loop. Whenever GDB | |
128 | core decides to handle the event, and calls into linux-nat.c, we | |
129 | process things as in sync mode, except that the we never block in | |
130 | sigsuspend. | |
131 | ||
132 | While processing an event, we may end up momentarily blocked in | |
133 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
134 | return quickly. E.g., in all-stop mode, before reporting to the core | |
135 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
136 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
137 | Note that this is different from blocking indefinitely waiting for the | |
138 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
139 | |
140 | Use of signals | |
141 | ============== | |
142 | ||
143 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
144 | signal is not entirely significant; we just need for a signal to be delivered, | |
145 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
146 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
147 | be queued once; we do not keep track of other sources of SIGSTOP. | |
148 | ||
149 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
150 | use them, because they have special behavior when the signal is generated - | |
151 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
152 | kills the entire thread group. | |
153 | ||
154 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
155 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
156 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
157 | ||
158 | We could use a real-time signal instead. This would solve those problems; we | |
159 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
160 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
161 | generates it, and there are races with trying to find a signal that is not | |
162 | blocked. */ | |
a0ef4274 | 163 | |
dba24537 AC |
164 | #ifndef O_LARGEFILE |
165 | #define O_LARGEFILE 0 | |
166 | #endif | |
0274a8ce | 167 | |
433bbbf8 | 168 | /* Does the current host support PTRACE_GETREGSET? */ |
0bdb2f78 | 169 | enum tribool have_ptrace_getregset = TRIBOOL_UNKNOWN; |
433bbbf8 | 170 | |
10d6c8cd DJ |
171 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
172 | the use of the multi-threaded target. */ | |
173 | static struct target_ops *linux_ops; | |
f973ed9c | 174 | static struct target_ops linux_ops_saved; |
10d6c8cd | 175 | |
9f0bdab8 | 176 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
177 | static void (*linux_nat_new_thread) (struct lwp_info *); |
178 | ||
26cb8b7c PA |
179 | /* The method to call, if any, when a new fork is attached. */ |
180 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
181 | ||
182 | /* The method to call, if any, when a process is no longer | |
183 | attached. */ | |
184 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
185 | ||
7b50312a PA |
186 | /* Hook to call prior to resuming a thread. */ |
187 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 188 | |
5b009018 PA |
189 | /* The method to call, if any, when the siginfo object needs to be |
190 | converted between the layout returned by ptrace, and the layout in | |
191 | the architecture of the inferior. */ | |
a5362b9a | 192 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
193 | gdb_byte *, |
194 | int); | |
195 | ||
ac264b3b MS |
196 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
197 | Called by our to_xfer_partial. */ | |
4ac248ca | 198 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 199 | |
6a3cb8e8 PA |
200 | /* The saved to_close method, inherited from inf-ptrace.c. |
201 | Called by our to_close. */ | |
202 | static void (*super_close) (struct target_ops *); | |
203 | ||
ccce17b0 | 204 | static unsigned int debug_linux_nat; |
920d2a44 AC |
205 | static void |
206 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
207 | struct cmd_list_element *c, const char *value) | |
208 | { | |
209 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
210 | value); | |
211 | } | |
d6b0e80f | 212 | |
ae087d01 DJ |
213 | struct simple_pid_list |
214 | { | |
215 | int pid; | |
3d799a95 | 216 | int status; |
ae087d01 DJ |
217 | struct simple_pid_list *next; |
218 | }; | |
219 | struct simple_pid_list *stopped_pids; | |
220 | ||
3dd5b83d PA |
221 | /* Async mode support. */ |
222 | ||
b84876c2 PA |
223 | /* The read/write ends of the pipe registered as waitable file in the |
224 | event loop. */ | |
225 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
226 | ||
198297aa PA |
227 | /* True if we're currently in async mode. */ |
228 | #define linux_is_async_p() (linux_nat_event_pipe[0] != -1) | |
229 | ||
7feb7d06 | 230 | /* Flush the event pipe. */ |
b84876c2 | 231 | |
7feb7d06 PA |
232 | static void |
233 | async_file_flush (void) | |
b84876c2 | 234 | { |
7feb7d06 PA |
235 | int ret; |
236 | char buf; | |
b84876c2 | 237 | |
7feb7d06 | 238 | do |
b84876c2 | 239 | { |
7feb7d06 | 240 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 241 | } |
7feb7d06 | 242 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
243 | } |
244 | ||
7feb7d06 PA |
245 | /* Put something (anything, doesn't matter what, or how much) in event |
246 | pipe, so that the select/poll in the event-loop realizes we have | |
247 | something to process. */ | |
252fbfc8 | 248 | |
b84876c2 | 249 | static void |
7feb7d06 | 250 | async_file_mark (void) |
b84876c2 | 251 | { |
7feb7d06 | 252 | int ret; |
b84876c2 | 253 | |
7feb7d06 PA |
254 | /* It doesn't really matter what the pipe contains, as long we end |
255 | up with something in it. Might as well flush the previous | |
256 | left-overs. */ | |
257 | async_file_flush (); | |
b84876c2 | 258 | |
7feb7d06 | 259 | do |
b84876c2 | 260 | { |
7feb7d06 | 261 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 262 | } |
7feb7d06 | 263 | while (ret == -1 && errno == EINTR); |
b84876c2 | 264 | |
7feb7d06 PA |
265 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
266 | be awakened anyway. */ | |
b84876c2 PA |
267 | } |
268 | ||
7feb7d06 PA |
269 | static int kill_lwp (int lwpid, int signo); |
270 | ||
271 | static int stop_callback (struct lwp_info *lp, void *data); | |
2db9a427 | 272 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
7feb7d06 PA |
273 | |
274 | static void block_child_signals (sigset_t *prev_mask); | |
275 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
276 | |
277 | struct lwp_info; | |
278 | static struct lwp_info *add_lwp (ptid_t ptid); | |
279 | static void purge_lwp_list (int pid); | |
4403d8e9 | 280 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
281 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
282 | ||
8a99810d PA |
283 | static int lwp_status_pending_p (struct lwp_info *lp); |
284 | ||
9c02b525 PA |
285 | static int check_stopped_by_breakpoint (struct lwp_info *lp); |
286 | static int sigtrap_is_event (int status); | |
287 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
288 | ||
cff068da GB |
289 | \f |
290 | /* LWP accessors. */ | |
291 | ||
292 | /* See nat/linux-nat.h. */ | |
293 | ||
294 | ptid_t | |
295 | ptid_of_lwp (struct lwp_info *lwp) | |
296 | { | |
297 | return lwp->ptid; | |
298 | } | |
299 | ||
300 | /* See nat/linux-nat.h. */ | |
301 | ||
4b134ca1 GB |
302 | void |
303 | lwp_set_arch_private_info (struct lwp_info *lwp, | |
304 | struct arch_lwp_info *info) | |
305 | { | |
306 | lwp->arch_private = info; | |
307 | } | |
308 | ||
309 | /* See nat/linux-nat.h. */ | |
310 | ||
311 | struct arch_lwp_info * | |
312 | lwp_arch_private_info (struct lwp_info *lwp) | |
313 | { | |
314 | return lwp->arch_private; | |
315 | } | |
316 | ||
317 | /* See nat/linux-nat.h. */ | |
318 | ||
cff068da GB |
319 | int |
320 | lwp_is_stopped (struct lwp_info *lwp) | |
321 | { | |
322 | return lwp->stopped; | |
323 | } | |
324 | ||
325 | /* See nat/linux-nat.h. */ | |
326 | ||
327 | enum target_stop_reason | |
328 | lwp_stop_reason (struct lwp_info *lwp) | |
329 | { | |
330 | return lwp->stop_reason; | |
331 | } | |
332 | ||
ae087d01 DJ |
333 | \f |
334 | /* Trivial list manipulation functions to keep track of a list of | |
335 | new stopped processes. */ | |
336 | static void | |
3d799a95 | 337 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 | 338 | { |
8d749320 | 339 | struct simple_pid_list *new_pid = XNEW (struct simple_pid_list); |
e0881a8e | 340 | |
ae087d01 | 341 | new_pid->pid = pid; |
3d799a95 | 342 | new_pid->status = status; |
ae087d01 DJ |
343 | new_pid->next = *listp; |
344 | *listp = new_pid; | |
345 | } | |
346 | ||
347 | static int | |
46a96992 | 348 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
349 | { |
350 | struct simple_pid_list **p; | |
351 | ||
352 | for (p = listp; *p != NULL; p = &(*p)->next) | |
353 | if ((*p)->pid == pid) | |
354 | { | |
355 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 356 | |
46a96992 | 357 | *statusp = (*p)->status; |
ae087d01 DJ |
358 | xfree (*p); |
359 | *p = next; | |
360 | return 1; | |
361 | } | |
362 | return 0; | |
363 | } | |
364 | ||
de0d863e DB |
365 | /* Return the ptrace options that we want to try to enable. */ |
366 | ||
367 | static int | |
368 | linux_nat_ptrace_options (int attached) | |
369 | { | |
370 | int options = 0; | |
371 | ||
372 | if (!attached) | |
373 | options |= PTRACE_O_EXITKILL; | |
374 | ||
375 | options |= (PTRACE_O_TRACESYSGOOD | |
376 | | PTRACE_O_TRACEVFORKDONE | |
377 | | PTRACE_O_TRACEVFORK | |
378 | | PTRACE_O_TRACEFORK | |
379 | | PTRACE_O_TRACEEXEC); | |
380 | ||
381 | return options; | |
382 | } | |
383 | ||
96d7229d | 384 | /* Initialize ptrace warnings and check for supported ptrace |
beed38b8 JB |
385 | features given PID. |
386 | ||
387 | ATTACHED should be nonzero iff we attached to the inferior. */ | |
3993f6b1 DJ |
388 | |
389 | static void | |
beed38b8 | 390 | linux_init_ptrace (pid_t pid, int attached) |
3993f6b1 | 391 | { |
de0d863e DB |
392 | int options = linux_nat_ptrace_options (attached); |
393 | ||
394 | linux_enable_event_reporting (pid, options); | |
96d7229d | 395 | linux_ptrace_init_warnings (); |
4de4c07c DJ |
396 | } |
397 | ||
6d8fd2b7 | 398 | static void |
f045800c | 399 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 400 | { |
beed38b8 | 401 | linux_init_ptrace (pid, 1); |
4de4c07c DJ |
402 | } |
403 | ||
10d6c8cd | 404 | static void |
2e97a79e | 405 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 406 | { |
beed38b8 | 407 | linux_init_ptrace (ptid_get_pid (ptid), 0); |
4de4c07c DJ |
408 | } |
409 | ||
4403d8e9 JK |
410 | /* Return the number of known LWPs in the tgid given by PID. */ |
411 | ||
412 | static int | |
413 | num_lwps (int pid) | |
414 | { | |
415 | int count = 0; | |
416 | struct lwp_info *lp; | |
417 | ||
418 | for (lp = lwp_list; lp; lp = lp->next) | |
419 | if (ptid_get_pid (lp->ptid) == pid) | |
420 | count++; | |
421 | ||
422 | return count; | |
423 | } | |
424 | ||
425 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
426 | ||
427 | static void | |
428 | delete_lwp_cleanup (void *lp_voidp) | |
429 | { | |
9a3c8263 | 430 | struct lwp_info *lp = (struct lwp_info *) lp_voidp; |
4403d8e9 JK |
431 | |
432 | delete_lwp (lp->ptid); | |
433 | } | |
434 | ||
d83ad864 DB |
435 | /* Target hook for follow_fork. On entry inferior_ptid must be the |
436 | ptid of the followed inferior. At return, inferior_ptid will be | |
437 | unchanged. */ | |
438 | ||
6d8fd2b7 | 439 | static int |
07107ca6 LM |
440 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
441 | int detach_fork) | |
3993f6b1 | 442 | { |
d83ad864 | 443 | if (!follow_child) |
4de4c07c | 444 | { |
6c95b8df | 445 | struct lwp_info *child_lp = NULL; |
d83ad864 DB |
446 | int status = W_STOPCODE (0); |
447 | struct cleanup *old_chain; | |
448 | int has_vforked; | |
79639e11 | 449 | ptid_t parent_ptid, child_ptid; |
d83ad864 DB |
450 | int parent_pid, child_pid; |
451 | ||
452 | has_vforked = (inferior_thread ()->pending_follow.kind | |
453 | == TARGET_WAITKIND_VFORKED); | |
79639e11 PA |
454 | parent_ptid = inferior_ptid; |
455 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; | |
456 | parent_pid = ptid_get_lwp (parent_ptid); | |
457 | child_pid = ptid_get_lwp (child_ptid); | |
4de4c07c | 458 | |
1777feb0 | 459 | /* We're already attached to the parent, by default. */ |
d83ad864 | 460 | old_chain = save_inferior_ptid (); |
79639e11 | 461 | inferior_ptid = child_ptid; |
d83ad864 DB |
462 | child_lp = add_lwp (inferior_ptid); |
463 | child_lp->stopped = 1; | |
464 | child_lp->last_resume_kind = resume_stop; | |
4de4c07c | 465 | |
ac264b3b MS |
466 | /* Detach new forked process? */ |
467 | if (detach_fork) | |
f75c00e4 | 468 | { |
4403d8e9 JK |
469 | make_cleanup (delete_lwp_cleanup, child_lp); |
470 | ||
4403d8e9 JK |
471 | if (linux_nat_prepare_to_resume != NULL) |
472 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
473 | |
474 | /* When debugging an inferior in an architecture that supports | |
475 | hardware single stepping on a kernel without commit | |
476 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
477 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
478 | set if the parent process had them set. | |
479 | To work around this, single step the child process | |
480 | once before detaching to clear the flags. */ | |
481 | ||
482 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
483 | (child_lp->ptid))) | |
484 | { | |
c077881a HZ |
485 | linux_disable_event_reporting (child_pid); |
486 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
487 | perror_with_name (_("Couldn't do single step")); | |
488 | if (my_waitpid (child_pid, &status, 0) < 0) | |
489 | perror_with_name (_("Couldn't wait vfork process")); | |
490 | } | |
491 | ||
492 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
493 | { |
494 | int signo; | |
495 | ||
496 | signo = WSTOPSIG (status); | |
497 | if (signo != 0 | |
498 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
499 | signo = 0; | |
500 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
501 | } | |
4403d8e9 | 502 | |
d83ad864 | 503 | /* Resets value of inferior_ptid to parent ptid. */ |
4403d8e9 | 504 | do_cleanups (old_chain); |
ac264b3b MS |
505 | } |
506 | else | |
507 | { | |
6c95b8df | 508 | /* Let the thread_db layer learn about this new process. */ |
2277426b | 509 | check_for_thread_db (); |
ac264b3b | 510 | } |
9016a515 | 511 | |
d83ad864 DB |
512 | do_cleanups (old_chain); |
513 | ||
9016a515 DJ |
514 | if (has_vforked) |
515 | { | |
3ced3da4 | 516 | struct lwp_info *parent_lp; |
6c95b8df | 517 | |
79639e11 | 518 | parent_lp = find_lwp_pid (parent_ptid); |
96d7229d | 519 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 520 | |
96d7229d | 521 | if (linux_supports_tracevforkdone ()) |
9016a515 | 522 | { |
6c95b8df PA |
523 | if (debug_linux_nat) |
524 | fprintf_unfiltered (gdb_stdlog, | |
525 | "LCFF: waiting for VFORK_DONE on %d\n", | |
526 | parent_pid); | |
3ced3da4 | 527 | parent_lp->stopped = 1; |
9016a515 | 528 | |
6c95b8df PA |
529 | /* We'll handle the VFORK_DONE event like any other |
530 | event, in target_wait. */ | |
9016a515 DJ |
531 | } |
532 | else | |
533 | { | |
534 | /* We can't insert breakpoints until the child has | |
535 | finished with the shared memory region. We need to | |
536 | wait until that happens. Ideal would be to just | |
537 | call: | |
538 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
539 | - waitpid (parent_pid, &status, __WALL); | |
540 | However, most architectures can't handle a syscall | |
541 | being traced on the way out if it wasn't traced on | |
542 | the way in. | |
543 | ||
544 | We might also think to loop, continuing the child | |
545 | until it exits or gets a SIGTRAP. One problem is | |
546 | that the child might call ptrace with PTRACE_TRACEME. | |
547 | ||
548 | There's no simple and reliable way to figure out when | |
549 | the vforked child will be done with its copy of the | |
550 | shared memory. We could step it out of the syscall, | |
551 | two instructions, let it go, and then single-step the | |
552 | parent once. When we have hardware single-step, this | |
553 | would work; with software single-step it could still | |
554 | be made to work but we'd have to be able to insert | |
555 | single-step breakpoints in the child, and we'd have | |
556 | to insert -just- the single-step breakpoint in the | |
557 | parent. Very awkward. | |
558 | ||
559 | In the end, the best we can do is to make sure it | |
560 | runs for a little while. Hopefully it will be out of | |
561 | range of any breakpoints we reinsert. Usually this | |
562 | is only the single-step breakpoint at vfork's return | |
563 | point. */ | |
564 | ||
6c95b8df PA |
565 | if (debug_linux_nat) |
566 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
567 | "LCFF: no VFORK_DONE " |
568 | "support, sleeping a bit\n"); | |
6c95b8df | 569 | |
9016a515 | 570 | usleep (10000); |
9016a515 | 571 | |
6c95b8df PA |
572 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
573 | and leave it pending. The next linux_nat_resume call | |
574 | will notice a pending event, and bypasses actually | |
575 | resuming the inferior. */ | |
3ced3da4 PA |
576 | parent_lp->status = 0; |
577 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
578 | parent_lp->stopped = 1; | |
6c95b8df PA |
579 | |
580 | /* If we're in async mode, need to tell the event loop | |
581 | there's something here to process. */ | |
d9d41e78 | 582 | if (target_is_async_p ()) |
6c95b8df PA |
583 | async_file_mark (); |
584 | } | |
9016a515 | 585 | } |
4de4c07c | 586 | } |
3993f6b1 | 587 | else |
4de4c07c | 588 | { |
3ced3da4 | 589 | struct lwp_info *child_lp; |
4de4c07c | 590 | |
3ced3da4 PA |
591 | child_lp = add_lwp (inferior_ptid); |
592 | child_lp->stopped = 1; | |
25289eb2 | 593 | child_lp->last_resume_kind = resume_stop; |
6c95b8df | 594 | |
6c95b8df | 595 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 596 | check_for_thread_db (); |
4de4c07c DJ |
597 | } |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
4de4c07c | 602 | \f |
77b06cd7 | 603 | static int |
a863b201 | 604 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 605 | { |
96d7229d | 606 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
607 | } |
608 | ||
eb73ad13 | 609 | static int |
973fc227 | 610 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
611 | { |
612 | return 0; | |
613 | } | |
614 | ||
77b06cd7 | 615 | static int |
3ecc7da0 | 616 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 617 | { |
96d7229d | 618 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
619 | } |
620 | ||
eb73ad13 | 621 | static int |
e98cf0cd | 622 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
623 | { |
624 | return 0; | |
625 | } | |
626 | ||
77b06cd7 | 627 | static int |
ba025e51 | 628 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 629 | { |
96d7229d | 630 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
631 | } |
632 | ||
eb73ad13 | 633 | static int |
758e29d2 | 634 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
635 | { |
636 | return 0; | |
637 | } | |
638 | ||
a96d9b2e | 639 | static int |
ff214e67 TT |
640 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
641 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
642 | int table_size, int *table) |
643 | { | |
96d7229d | 644 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
645 | return 1; |
646 | ||
a96d9b2e SDJ |
647 | /* On GNU/Linux, we ignore the arguments. It means that we only |
648 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 649 | |
a96d9b2e SDJ |
650 | Also, we do not use the `table' information because we do not |
651 | filter system calls here. We let GDB do the logic for us. */ | |
652 | return 0; | |
653 | } | |
654 | ||
d6b0e80f AC |
655 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
656 | are processes sharing the same VM space. A multi-threaded process | |
657 | is basically a group of such processes. However, such a grouping | |
658 | is almost entirely a user-space issue; the kernel doesn't enforce | |
659 | such a grouping at all (this might change in the future). In | |
660 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
661 | Threads library) to provide such a grouping. | |
662 | ||
663 | It is perfectly well possible to write a multi-threaded application | |
664 | without the assistance of a threads library, by using the clone | |
665 | system call directly. This module should be able to give some | |
666 | rudimentary support for debugging such applications if developers | |
667 | specify the CLONE_PTRACE flag in the clone system call, and are | |
668 | using the Linux kernel 2.4 or above. | |
669 | ||
670 | Note that there are some peculiarities in GNU/Linux that affect | |
671 | this code: | |
672 | ||
673 | - In general one should specify the __WCLONE flag to waitpid in | |
674 | order to make it report events for any of the cloned processes | |
675 | (and leave it out for the initial process). However, if a cloned | |
676 | process has exited the exit status is only reported if the | |
677 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
678 | we cannot use it since GDB must work on older systems too. | |
679 | ||
680 | - When a traced, cloned process exits and is waited for by the | |
681 | debugger, the kernel reassigns it to the original parent and | |
682 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
683 | library doesn't notice this, which leads to the "zombie problem": | |
684 | When debugged a multi-threaded process that spawns a lot of | |
685 | threads will run out of processes, even if the threads exit, | |
686 | because the "zombies" stay around. */ | |
687 | ||
688 | /* List of known LWPs. */ | |
9f0bdab8 | 689 | struct lwp_info *lwp_list; |
d6b0e80f AC |
690 | \f |
691 | ||
d6b0e80f AC |
692 | /* Original signal mask. */ |
693 | static sigset_t normal_mask; | |
694 | ||
695 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
696 | _initialize_linux_nat. */ | |
697 | static sigset_t suspend_mask; | |
698 | ||
7feb7d06 PA |
699 | /* Signals to block to make that sigsuspend work. */ |
700 | static sigset_t blocked_mask; | |
701 | ||
702 | /* SIGCHLD action. */ | |
703 | struct sigaction sigchld_action; | |
b84876c2 | 704 | |
7feb7d06 PA |
705 | /* Block child signals (SIGCHLD and linux threads signals), and store |
706 | the previous mask in PREV_MASK. */ | |
84e46146 | 707 | |
7feb7d06 PA |
708 | static void |
709 | block_child_signals (sigset_t *prev_mask) | |
710 | { | |
711 | /* Make sure SIGCHLD is blocked. */ | |
712 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
713 | sigaddset (&blocked_mask, SIGCHLD); | |
714 | ||
715 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
716 | } | |
717 | ||
718 | /* Restore child signals mask, previously returned by | |
719 | block_child_signals. */ | |
720 | ||
721 | static void | |
722 | restore_child_signals_mask (sigset_t *prev_mask) | |
723 | { | |
724 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
725 | } | |
2455069d UW |
726 | |
727 | /* Mask of signals to pass directly to the inferior. */ | |
728 | static sigset_t pass_mask; | |
729 | ||
730 | /* Update signals to pass to the inferior. */ | |
731 | static void | |
94bedb42 TT |
732 | linux_nat_pass_signals (struct target_ops *self, |
733 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
734 | { |
735 | int signo; | |
736 | ||
737 | sigemptyset (&pass_mask); | |
738 | ||
739 | for (signo = 1; signo < NSIG; signo++) | |
740 | { | |
2ea28649 | 741 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
742 | if (target_signo < numsigs && pass_signals[target_signo]) |
743 | sigaddset (&pass_mask, signo); | |
744 | } | |
745 | } | |
746 | ||
d6b0e80f AC |
747 | \f |
748 | ||
749 | /* Prototypes for local functions. */ | |
750 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 751 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 752 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
20ba1ce6 | 753 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
710151dd | 754 | |
d6b0e80f | 755 | \f |
d6b0e80f | 756 | |
7b50312a PA |
757 | /* Destroy and free LP. */ |
758 | ||
759 | static void | |
760 | lwp_free (struct lwp_info *lp) | |
761 | { | |
762 | xfree (lp->arch_private); | |
763 | xfree (lp); | |
764 | } | |
765 | ||
d90e17a7 PA |
766 | /* Remove all LWPs belong to PID from the lwp list. */ |
767 | ||
768 | static void | |
769 | purge_lwp_list (int pid) | |
770 | { | |
771 | struct lwp_info *lp, *lpprev, *lpnext; | |
772 | ||
773 | lpprev = NULL; | |
774 | ||
775 | for (lp = lwp_list; lp; lp = lpnext) | |
776 | { | |
777 | lpnext = lp->next; | |
778 | ||
779 | if (ptid_get_pid (lp->ptid) == pid) | |
780 | { | |
781 | if (lp == lwp_list) | |
782 | lwp_list = lp->next; | |
783 | else | |
784 | lpprev->next = lp->next; | |
785 | ||
7b50312a | 786 | lwp_free (lp); |
d90e17a7 PA |
787 | } |
788 | else | |
789 | lpprev = lp; | |
790 | } | |
791 | } | |
792 | ||
26cb8b7c PA |
793 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
794 | in the process. Return a pointer to the structure describing the | |
795 | new LWP. | |
796 | ||
797 | This differs from add_lwp in that we don't let the arch specific | |
798 | bits know about this new thread. Current clients of this callback | |
799 | take the opportunity to install watchpoints in the new thread, and | |
800 | we shouldn't do that for the first thread. If we're spawning a | |
801 | child ("run"), the thread executes the shell wrapper first, and we | |
802 | shouldn't touch it until it execs the program we want to debug. | |
803 | For "attach", it'd be okay to call the callback, but it's not | |
804 | necessary, because watchpoints can't yet have been inserted into | |
805 | the inferior. */ | |
d6b0e80f AC |
806 | |
807 | static struct lwp_info * | |
26cb8b7c | 808 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
809 | { |
810 | struct lwp_info *lp; | |
811 | ||
dfd4cc63 | 812 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 813 | |
8d749320 | 814 | lp = XNEW (struct lwp_info); |
d6b0e80f AC |
815 | |
816 | memset (lp, 0, sizeof (struct lwp_info)); | |
817 | ||
25289eb2 | 818 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
819 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
820 | ||
821 | lp->ptid = ptid; | |
dc146f7c | 822 | lp->core = -1; |
d6b0e80f AC |
823 | |
824 | lp->next = lwp_list; | |
825 | lwp_list = lp; | |
d6b0e80f | 826 | |
26cb8b7c PA |
827 | return lp; |
828 | } | |
829 | ||
830 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
831 | structure describing the new LWP. The LWP should already be | |
832 | stopped. */ | |
833 | ||
834 | static struct lwp_info * | |
835 | add_lwp (ptid_t ptid) | |
836 | { | |
837 | struct lwp_info *lp; | |
838 | ||
839 | lp = add_initial_lwp (ptid); | |
840 | ||
6e012a6c PA |
841 | /* Let the arch specific bits know about this new thread. Current |
842 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
843 | watchpoints in the new thread. We don't do this for the first |
844 | thread though. See add_initial_lwp. */ | |
845 | if (linux_nat_new_thread != NULL) | |
7b50312a | 846 | linux_nat_new_thread (lp); |
9f0bdab8 | 847 | |
d6b0e80f AC |
848 | return lp; |
849 | } | |
850 | ||
851 | /* Remove the LWP specified by PID from the list. */ | |
852 | ||
853 | static void | |
854 | delete_lwp (ptid_t ptid) | |
855 | { | |
856 | struct lwp_info *lp, *lpprev; | |
857 | ||
858 | lpprev = NULL; | |
859 | ||
860 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
861 | if (ptid_equal (lp->ptid, ptid)) | |
862 | break; | |
863 | ||
864 | if (!lp) | |
865 | return; | |
866 | ||
d6b0e80f AC |
867 | if (lpprev) |
868 | lpprev->next = lp->next; | |
869 | else | |
870 | lwp_list = lp->next; | |
871 | ||
7b50312a | 872 | lwp_free (lp); |
d6b0e80f AC |
873 | } |
874 | ||
875 | /* Return a pointer to the structure describing the LWP corresponding | |
876 | to PID. If no corresponding LWP could be found, return NULL. */ | |
877 | ||
878 | static struct lwp_info * | |
879 | find_lwp_pid (ptid_t ptid) | |
880 | { | |
881 | struct lwp_info *lp; | |
882 | int lwp; | |
883 | ||
dfd4cc63 LM |
884 | if (ptid_lwp_p (ptid)) |
885 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 886 | else |
dfd4cc63 | 887 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
888 | |
889 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 890 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
891 | return lp; |
892 | ||
893 | return NULL; | |
894 | } | |
895 | ||
6d4ee8c6 | 896 | /* See nat/linux-nat.h. */ |
d6b0e80f AC |
897 | |
898 | struct lwp_info * | |
d90e17a7 | 899 | iterate_over_lwps (ptid_t filter, |
6d4ee8c6 | 900 | iterate_over_lwps_ftype callback, |
d90e17a7 | 901 | void *data) |
d6b0e80f AC |
902 | { |
903 | struct lwp_info *lp, *lpnext; | |
904 | ||
905 | for (lp = lwp_list; lp; lp = lpnext) | |
906 | { | |
907 | lpnext = lp->next; | |
d90e17a7 PA |
908 | |
909 | if (ptid_match (lp->ptid, filter)) | |
910 | { | |
6d4ee8c6 | 911 | if ((*callback) (lp, data) != 0) |
d90e17a7 PA |
912 | return lp; |
913 | } | |
d6b0e80f AC |
914 | } |
915 | ||
916 | return NULL; | |
917 | } | |
918 | ||
2277426b PA |
919 | /* Update our internal state when changing from one checkpoint to |
920 | another indicated by NEW_PTID. We can only switch single-threaded | |
921 | applications, so we only create one new LWP, and the previous list | |
922 | is discarded. */ | |
f973ed9c DJ |
923 | |
924 | void | |
925 | linux_nat_switch_fork (ptid_t new_ptid) | |
926 | { | |
927 | struct lwp_info *lp; | |
928 | ||
dfd4cc63 | 929 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 930 | |
f973ed9c DJ |
931 | lp = add_lwp (new_ptid); |
932 | lp->stopped = 1; | |
e26af52f | 933 | |
2277426b PA |
934 | /* This changes the thread's ptid while preserving the gdb thread |
935 | num. Also changes the inferior pid, while preserving the | |
936 | inferior num. */ | |
937 | thread_change_ptid (inferior_ptid, new_ptid); | |
938 | ||
939 | /* We've just told GDB core that the thread changed target id, but, | |
940 | in fact, it really is a different thread, with different register | |
941 | contents. */ | |
942 | registers_changed (); | |
e26af52f DJ |
943 | } |
944 | ||
e26af52f DJ |
945 | /* Handle the exit of a single thread LP. */ |
946 | ||
947 | static void | |
948 | exit_lwp (struct lwp_info *lp) | |
949 | { | |
e09875d4 | 950 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
951 | |
952 | if (th) | |
e26af52f | 953 | { |
17faa917 DJ |
954 | if (print_thread_events) |
955 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
956 | ||
4f8d22e3 | 957 | delete_thread (lp->ptid); |
e26af52f DJ |
958 | } |
959 | ||
960 | delete_lwp (lp->ptid); | |
961 | } | |
962 | ||
a0ef4274 DJ |
963 | /* Wait for the LWP specified by LP, which we have just attached to. |
964 | Returns a wait status for that LWP, to cache. */ | |
965 | ||
966 | static int | |
967 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
968 | int *signalled) | |
969 | { | |
dfd4cc63 | 970 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
971 | int status; |
972 | ||
644cebc9 | 973 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
974 | { |
975 | if (debug_linux_nat) | |
976 | fprintf_unfiltered (gdb_stdlog, | |
977 | "LNPAW: Attaching to a stopped process\n"); | |
978 | ||
979 | /* The process is definitely stopped. It is in a job control | |
980 | stop, unless the kernel predates the TASK_STOPPED / | |
981 | TASK_TRACED distinction, in which case it might be in a | |
982 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
983 | can kill it, signal it, et cetera. | |
984 | ||
985 | First make sure there is a pending SIGSTOP. Since we are | |
986 | already attached, the process can not transition from stopped | |
987 | to running without a PTRACE_CONT; so we know this signal will | |
988 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
989 | probably already in the queue (unless this kernel is old | |
990 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
991 | is not an RT signal, it can only be queued once. */ | |
992 | kill_lwp (pid, SIGSTOP); | |
993 | ||
994 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
995 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
996 | ptrace (PTRACE_CONT, pid, 0, 0); | |
997 | } | |
998 | ||
999 | /* Make sure the initial process is stopped. The user-level threads | |
1000 | layer might want to poke around in the inferior, and that won't | |
1001 | work if things haven't stabilized yet. */ | |
1002 | new_pid = my_waitpid (pid, &status, 0); | |
1003 | if (new_pid == -1 && errno == ECHILD) | |
1004 | { | |
1005 | if (first) | |
1006 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1007 | ||
1008 | /* Try again with __WCLONE to check cloned processes. */ | |
1009 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1010 | *cloned = 1; | |
1011 | } | |
1012 | ||
dacc9cb2 PP |
1013 | gdb_assert (pid == new_pid); |
1014 | ||
1015 | if (!WIFSTOPPED (status)) | |
1016 | { | |
1017 | /* The pid we tried to attach has apparently just exited. */ | |
1018 | if (debug_linux_nat) | |
1019 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1020 | pid, status_to_str (status)); | |
1021 | return status; | |
1022 | } | |
a0ef4274 DJ |
1023 | |
1024 | if (WSTOPSIG (status) != SIGSTOP) | |
1025 | { | |
1026 | *signalled = 1; | |
1027 | if (debug_linux_nat) | |
1028 | fprintf_unfiltered (gdb_stdlog, | |
1029 | "LNPAW: Received %s after attaching\n", | |
1030 | status_to_str (status)); | |
1031 | } | |
1032 | ||
1033 | return status; | |
1034 | } | |
1035 | ||
b84876c2 | 1036 | static void |
136d6dae VP |
1037 | linux_nat_create_inferior (struct target_ops *ops, |
1038 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1039 | int from_tty) |
1040 | { | |
8cc73a39 SDJ |
1041 | struct cleanup *restore_personality |
1042 | = maybe_disable_address_space_randomization (disable_randomization); | |
b84876c2 PA |
1043 | |
1044 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1045 | we have to mask the async mode. */ | |
1046 | ||
2455069d | 1047 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1048 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1049 | |
136d6dae | 1050 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1051 | |
8cc73a39 | 1052 | do_cleanups (restore_personality); |
b84876c2 PA |
1053 | } |
1054 | ||
8784d563 PA |
1055 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not |
1056 | already attached. Returns true if a new LWP is found, false | |
1057 | otherwise. */ | |
1058 | ||
1059 | static int | |
1060 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1061 | { | |
1062 | struct lwp_info *lp; | |
1063 | ||
1064 | /* Ignore LWPs we're already attached to. */ | |
1065 | lp = find_lwp_pid (ptid); | |
1066 | if (lp == NULL) | |
1067 | { | |
1068 | int lwpid = ptid_get_lwp (ptid); | |
1069 | ||
1070 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) | |
1071 | { | |
1072 | int err = errno; | |
1073 | ||
1074 | /* Be quiet if we simply raced with the thread exiting. | |
1075 | EPERM is returned if the thread's task still exists, and | |
1076 | is marked as exited or zombie, as well as other | |
1077 | conditions, so in that case, confirm the status in | |
1078 | /proc/PID/status. */ | |
1079 | if (err == ESRCH | |
1080 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1081 | { | |
1082 | if (debug_linux_nat) | |
1083 | { | |
1084 | fprintf_unfiltered (gdb_stdlog, | |
1085 | "Cannot attach to lwp %d: " | |
1086 | "thread is gone (%d: %s)\n", | |
1087 | lwpid, err, safe_strerror (err)); | |
1088 | } | |
1089 | } | |
1090 | else | |
1091 | { | |
f71f0b0d | 1092 | warning (_("Cannot attach to lwp %d: %s"), |
8784d563 PA |
1093 | lwpid, |
1094 | linux_ptrace_attach_fail_reason_string (ptid, | |
1095 | err)); | |
1096 | } | |
1097 | } | |
1098 | else | |
1099 | { | |
1100 | if (debug_linux_nat) | |
1101 | fprintf_unfiltered (gdb_stdlog, | |
1102 | "PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1103 | target_pid_to_str (ptid)); | |
1104 | ||
1105 | lp = add_lwp (ptid); | |
1106 | lp->cloned = 1; | |
1107 | ||
1108 | /* The next time we wait for this LWP we'll see a SIGSTOP as | |
1109 | PTRACE_ATTACH brings it to a halt. */ | |
1110 | lp->signalled = 1; | |
1111 | ||
1112 | /* We need to wait for a stop before being able to make the | |
1113 | next ptrace call on this LWP. */ | |
1114 | lp->must_set_ptrace_flags = 1; | |
1115 | } | |
1116 | ||
1117 | return 1; | |
1118 | } | |
1119 | return 0; | |
1120 | } | |
1121 | ||
d6b0e80f | 1122 | static void |
c0939df1 | 1123 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1124 | { |
1125 | struct lwp_info *lp; | |
d6b0e80f | 1126 | int status; |
af990527 | 1127 | ptid_t ptid; |
d6b0e80f | 1128 | |
2455069d | 1129 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1130 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1131 | |
492d29ea | 1132 | TRY |
87b0bb13 JK |
1133 | { |
1134 | linux_ops->to_attach (ops, args, from_tty); | |
1135 | } | |
492d29ea | 1136 | CATCH (ex, RETURN_MASK_ERROR) |
87b0bb13 JK |
1137 | { |
1138 | pid_t pid = parse_pid_to_attach (args); | |
1139 | struct buffer buffer; | |
1140 | char *message, *buffer_s; | |
1141 | ||
1142 | message = xstrdup (ex.message); | |
1143 | make_cleanup (xfree, message); | |
1144 | ||
1145 | buffer_init (&buffer); | |
7ae1a6a6 | 1146 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1147 | |
1148 | buffer_grow_str0 (&buffer, ""); | |
1149 | buffer_s = buffer_finish (&buffer); | |
1150 | make_cleanup (xfree, buffer_s); | |
1151 | ||
7ae1a6a6 PA |
1152 | if (*buffer_s != '\0') |
1153 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1154 | else | |
1155 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1156 | } |
492d29ea | 1157 | END_CATCH |
d6b0e80f | 1158 | |
af990527 PA |
1159 | /* The ptrace base target adds the main thread with (pid,0,0) |
1160 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1161 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1162 | ptid_get_pid (inferior_ptid), | |
1163 | 0); | |
af990527 PA |
1164 | thread_change_ptid (inferior_ptid, ptid); |
1165 | ||
9f0bdab8 | 1166 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1167 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1168 | |
1169 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1170 | &lp->signalled); | |
dacc9cb2 PP |
1171 | if (!WIFSTOPPED (status)) |
1172 | { | |
1173 | if (WIFEXITED (status)) | |
1174 | { | |
1175 | int exit_code = WEXITSTATUS (status); | |
1176 | ||
1177 | target_terminal_ours (); | |
1178 | target_mourn_inferior (); | |
1179 | if (exit_code == 0) | |
1180 | error (_("Unable to attach: program exited normally.")); | |
1181 | else | |
1182 | error (_("Unable to attach: program exited with code %d."), | |
1183 | exit_code); | |
1184 | } | |
1185 | else if (WIFSIGNALED (status)) | |
1186 | { | |
2ea28649 | 1187 | enum gdb_signal signo; |
dacc9cb2 PP |
1188 | |
1189 | target_terminal_ours (); | |
1190 | target_mourn_inferior (); | |
1191 | ||
2ea28649 | 1192 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1193 | error (_("Unable to attach: program terminated with signal " |
1194 | "%s, %s."), | |
2ea28649 PA |
1195 | gdb_signal_to_name (signo), |
1196 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1197 | } |
1198 | ||
1199 | internal_error (__FILE__, __LINE__, | |
1200 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1201 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1202 | } |
1203 | ||
a0ef4274 | 1204 | lp->stopped = 1; |
9f0bdab8 | 1205 | |
a0ef4274 | 1206 | /* Save the wait status to report later. */ |
d6b0e80f | 1207 | lp->resumed = 1; |
a0ef4274 DJ |
1208 | if (debug_linux_nat) |
1209 | fprintf_unfiltered (gdb_stdlog, | |
1210 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1211 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1212 | |
7feb7d06 PA |
1213 | lp->status = status; |
1214 | ||
8784d563 PA |
1215 | /* We must attach to every LWP. If /proc is mounted, use that to |
1216 | find them now. The inferior may be using raw clone instead of | |
1217 | using pthreads. But even if it is using pthreads, thread_db | |
1218 | walks structures in the inferior's address space to find the list | |
1219 | of threads/LWPs, and those structures may well be corrupted. | |
1220 | Note that once thread_db is loaded, we'll still use it to list | |
1221 | threads and associate pthread info with each LWP. */ | |
1222 | linux_proc_attach_tgid_threads (ptid_get_pid (lp->ptid), | |
1223 | attach_proc_task_lwp_callback); | |
1224 | ||
7feb7d06 | 1225 | if (target_can_async_p ()) |
6a3753b3 | 1226 | target_async (1); |
d6b0e80f AC |
1227 | } |
1228 | ||
a0ef4274 DJ |
1229 | /* Get pending status of LP. */ |
1230 | static int | |
1231 | get_pending_status (struct lwp_info *lp, int *status) | |
1232 | { | |
a493e3e2 | 1233 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1234 | |
1235 | /* If we paused threads momentarily, we may have stored pending | |
1236 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1237 | and GDB core hasn't seen any signal for those threads. | |
1238 | Otherwise, the last signal reported to the core is found in the | |
1239 | thread object's stop_signal. | |
1240 | ||
1241 | There's a corner case that isn't handled here at present. Only | |
1242 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1243 | stop_signal make sense as a real signal to pass to the inferior. | |
1244 | Some catchpoint related events, like | |
1245 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1246 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1247 | those traps are debug API (ptrace in our case) related and |
1248 | induced; the inferior wouldn't see them if it wasn't being | |
1249 | traced. Hence, we should never pass them to the inferior, even | |
1250 | when set to pass state. Since this corner case isn't handled by | |
1251 | infrun.c when proceeding with a signal, for consistency, neither | |
1252 | do we handle it here (or elsewhere in the file we check for | |
1253 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1254 | this is really a corner case. */ | |
1255 | ||
1256 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1257 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1258 | else if (lp->status) |
2ea28649 | 1259 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
fbea99ea | 1260 | else if (target_is_non_stop_p () && !is_executing (lp->ptid)) |
ca2163eb PA |
1261 | { |
1262 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1263 | |
16c381f0 | 1264 | signo = tp->suspend.stop_signal; |
ca2163eb | 1265 | } |
fbea99ea | 1266 | else if (!target_is_non_stop_p ()) |
a0ef4274 | 1267 | { |
ca2163eb PA |
1268 | struct target_waitstatus last; |
1269 | ptid_t last_ptid; | |
4c28f408 | 1270 | |
ca2163eb | 1271 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1272 | |
dfd4cc63 | 1273 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1274 | { |
e09875d4 | 1275 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1276 | |
16c381f0 | 1277 | signo = tp->suspend.stop_signal; |
4c28f408 | 1278 | } |
ca2163eb | 1279 | } |
4c28f408 | 1280 | |
ca2163eb | 1281 | *status = 0; |
4c28f408 | 1282 | |
a493e3e2 | 1283 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1284 | { |
1285 | if (debug_linux_nat) | |
1286 | fprintf_unfiltered (gdb_stdlog, | |
1287 | "GPT: lwp %s has no pending signal\n", | |
1288 | target_pid_to_str (lp->ptid)); | |
1289 | } | |
1290 | else if (!signal_pass_state (signo)) | |
1291 | { | |
1292 | if (debug_linux_nat) | |
3e43a32a MS |
1293 | fprintf_unfiltered (gdb_stdlog, |
1294 | "GPT: lwp %s had signal %s, " | |
1295 | "but it is in no pass state\n", | |
ca2163eb | 1296 | target_pid_to_str (lp->ptid), |
2ea28649 | 1297 | gdb_signal_to_string (signo)); |
a0ef4274 | 1298 | } |
a0ef4274 | 1299 | else |
4c28f408 | 1300 | { |
2ea28649 | 1301 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1302 | |
1303 | if (debug_linux_nat) | |
1304 | fprintf_unfiltered (gdb_stdlog, | |
1305 | "GPT: lwp %s has pending signal %s\n", | |
1306 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1307 | gdb_signal_to_string (signo)); |
4c28f408 | 1308 | } |
a0ef4274 DJ |
1309 | |
1310 | return 0; | |
1311 | } | |
1312 | ||
d6b0e80f AC |
1313 | static int |
1314 | detach_callback (struct lwp_info *lp, void *data) | |
1315 | { | |
1316 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1317 | ||
1318 | if (debug_linux_nat && lp->status) | |
1319 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1320 | strsignal (WSTOPSIG (lp->status)), | |
1321 | target_pid_to_str (lp->ptid)); | |
1322 | ||
a0ef4274 DJ |
1323 | /* If there is a pending SIGSTOP, get rid of it. */ |
1324 | if (lp->signalled) | |
d6b0e80f | 1325 | { |
d6b0e80f AC |
1326 | if (debug_linux_nat) |
1327 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1328 | "DC: Sending SIGCONT to %s\n", |
1329 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1330 | |
dfd4cc63 | 1331 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1332 | lp->signalled = 0; |
d6b0e80f AC |
1333 | } |
1334 | ||
1335 | /* We don't actually detach from the LWP that has an id equal to the | |
1336 | overall process id just yet. */ | |
dfd4cc63 | 1337 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1338 | { |
a0ef4274 DJ |
1339 | int status = 0; |
1340 | ||
1341 | /* Pass on any pending signal for this LWP. */ | |
1342 | get_pending_status (lp, &status); | |
1343 | ||
7b50312a PA |
1344 | if (linux_nat_prepare_to_resume != NULL) |
1345 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1346 | errno = 0; |
dfd4cc63 | 1347 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1348 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1349 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1350 | safe_strerror (errno)); |
1351 | ||
1352 | if (debug_linux_nat) | |
1353 | fprintf_unfiltered (gdb_stdlog, | |
1354 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1355 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1356 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1357 | |
1358 | delete_lwp (lp->ptid); | |
1359 | } | |
1360 | ||
1361 | return 0; | |
1362 | } | |
1363 | ||
1364 | static void | |
52554a0e | 1365 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1366 | { |
b84876c2 | 1367 | int pid; |
a0ef4274 | 1368 | int status; |
d90e17a7 PA |
1369 | struct lwp_info *main_lwp; |
1370 | ||
dfd4cc63 | 1371 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1372 | |
ae5e0686 MK |
1373 | /* Don't unregister from the event loop, as there may be other |
1374 | inferiors running. */ | |
b84876c2 | 1375 | |
4c28f408 PA |
1376 | /* Stop all threads before detaching. ptrace requires that the |
1377 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1378 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1379 | /* ... and wait until all of them have reported back that |
1380 | they're no longer running. */ | |
d90e17a7 | 1381 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1382 | |
d90e17a7 | 1383 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1384 | |
1385 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1386 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1387 | |
1388 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1389 | |
a0ef4274 DJ |
1390 | /* Pass on any pending signal for the last LWP. */ |
1391 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1392 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1393 | && WIFSTOPPED (status)) |
1394 | { | |
52554a0e TT |
1395 | char *tem; |
1396 | ||
a0ef4274 DJ |
1397 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1398 | pass it along with PTRACE_DETACH. */ | |
224c3ddb | 1399 | tem = (char *) alloca (8); |
cde33bf1 | 1400 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1401 | args = tem; |
ddabfc73 TT |
1402 | if (debug_linux_nat) |
1403 | fprintf_unfiltered (gdb_stdlog, | |
1404 | "LND: Sending signal %s to %s\n", | |
1405 | args, | |
1406 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1407 | } |
1408 | ||
7b50312a PA |
1409 | if (linux_nat_prepare_to_resume != NULL) |
1410 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1411 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1412 | |
7a7d3353 PA |
1413 | if (forks_exist_p ()) |
1414 | { | |
1415 | /* Multi-fork case. The current inferior_ptid is being detached | |
1416 | from, but there are other viable forks to debug. Detach from | |
1417 | the current fork, and context-switch to the first | |
1418 | available. */ | |
1419 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1420 | } |
1421 | else | |
1422 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1423 | } |
1424 | ||
8a99810d PA |
1425 | /* Resume execution of the inferior process. If STEP is nonzero, |
1426 | single-step it. If SIGNAL is nonzero, give it that signal. */ | |
1427 | ||
1428 | static void | |
23f238d3 PA |
1429 | linux_resume_one_lwp_throw (struct lwp_info *lp, int step, |
1430 | enum gdb_signal signo) | |
8a99810d | 1431 | { |
8a99810d | 1432 | lp->step = step; |
9c02b525 PA |
1433 | |
1434 | /* stop_pc doubles as the PC the LWP had when it was last resumed. | |
1435 | We only presently need that if the LWP is stepped though (to | |
1436 | handle the case of stepping a breakpoint instruction). */ | |
1437 | if (step) | |
1438 | { | |
1439 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
1440 | ||
1441 | lp->stop_pc = regcache_read_pc (regcache); | |
1442 | } | |
1443 | else | |
1444 | lp->stop_pc = 0; | |
1445 | ||
8a99810d PA |
1446 | if (linux_nat_prepare_to_resume != NULL) |
1447 | linux_nat_prepare_to_resume (lp); | |
90ad5e1d | 1448 | linux_ops->to_resume (linux_ops, lp->ptid, step, signo); |
23f238d3 PA |
1449 | |
1450 | /* Successfully resumed. Clear state that no longer makes sense, | |
1451 | and mark the LWP as running. Must not do this before resuming | |
1452 | otherwise if that fails other code will be confused. E.g., we'd | |
1453 | later try to stop the LWP and hang forever waiting for a stop | |
1454 | status. Note that we must not throw after this is cleared, | |
1455 | otherwise handle_zombie_lwp_error would get confused. */ | |
8a99810d | 1456 | lp->stopped = 0; |
23f238d3 | 1457 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; |
8a99810d PA |
1458 | registers_changed_ptid (lp->ptid); |
1459 | } | |
1460 | ||
23f238d3 PA |
1461 | /* Called when we try to resume a stopped LWP and that errors out. If |
1462 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
1463 | or about to become), discard the error, clear any pending status | |
1464 | the LWP may have, and return true (we'll collect the exit status | |
1465 | soon enough). Otherwise, return false. */ | |
1466 | ||
1467 | static int | |
1468 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
1469 | { | |
1470 | /* If we get an error after resuming the LWP successfully, we'd | |
1471 | confuse !T state for the LWP being gone. */ | |
1472 | gdb_assert (lp->stopped); | |
1473 | ||
1474 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
1475 | because even if ptrace failed with ESRCH, the tracee may be "not | |
1476 | yet fully dead", but already refusing ptrace requests. In that | |
1477 | case the tracee has 'R (Running)' state for a little bit | |
1478 | (observed in Linux 3.18). See also the note on ESRCH in the | |
1479 | ptrace(2) man page. Instead, check whether the LWP has any state | |
1480 | other than ptrace-stopped. */ | |
1481 | ||
1482 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
1483 | if (linux_proc_pid_is_trace_stopped_nowarn (ptid_get_lwp (lp->ptid)) == 0) | |
1484 | { | |
1485 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
1486 | lp->status = 0; | |
1487 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
1488 | return 1; | |
1489 | } | |
1490 | return 0; | |
1491 | } | |
1492 | ||
1493 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
1494 | disappears while we try to resume it. */ | |
1495 | ||
1496 | static void | |
1497 | linux_resume_one_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) | |
1498 | { | |
1499 | TRY | |
1500 | { | |
1501 | linux_resume_one_lwp_throw (lp, step, signo); | |
1502 | } | |
1503 | CATCH (ex, RETURN_MASK_ERROR) | |
1504 | { | |
1505 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
1506 | throw_exception (ex); | |
1507 | } | |
1508 | END_CATCH | |
1509 | } | |
1510 | ||
d6b0e80f AC |
1511 | /* Resume LP. */ |
1512 | ||
25289eb2 | 1513 | static void |
e5ef252a | 1514 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1515 | { |
25289eb2 | 1516 | if (lp->stopped) |
6c95b8df | 1517 | { |
c9657e70 | 1518 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
25289eb2 PA |
1519 | |
1520 | if (inf->vfork_child != NULL) | |
1521 | { | |
1522 | if (debug_linux_nat) | |
1523 | fprintf_unfiltered (gdb_stdlog, | |
1524 | "RC: Not resuming %s (vfork parent)\n", | |
1525 | target_pid_to_str (lp->ptid)); | |
1526 | } | |
8a99810d | 1527 | else if (!lwp_status_pending_p (lp)) |
25289eb2 PA |
1528 | { |
1529 | if (debug_linux_nat) | |
1530 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1531 | "RC: Resuming sibling %s, %s, %s\n", |
1532 | target_pid_to_str (lp->ptid), | |
1533 | (signo != GDB_SIGNAL_0 | |
1534 | ? strsignal (gdb_signal_to_host (signo)) | |
1535 | : "0"), | |
1536 | step ? "step" : "resume"); | |
25289eb2 | 1537 | |
8a99810d | 1538 | linux_resume_one_lwp (lp, step, signo); |
25289eb2 PA |
1539 | } |
1540 | else | |
1541 | { | |
1542 | if (debug_linux_nat) | |
1543 | fprintf_unfiltered (gdb_stdlog, | |
1544 | "RC: Not resuming sibling %s (has pending)\n", | |
1545 | target_pid_to_str (lp->ptid)); | |
1546 | } | |
6c95b8df | 1547 | } |
25289eb2 | 1548 | else |
d6b0e80f | 1549 | { |
d90e17a7 PA |
1550 | if (debug_linux_nat) |
1551 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1552 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1553 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1554 | } |
25289eb2 | 1555 | } |
d6b0e80f | 1556 | |
8817a6f2 PA |
1557 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1558 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1559 | |
25289eb2 | 1560 | static int |
8817a6f2 | 1561 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1562 | { |
e5ef252a PA |
1563 | enum gdb_signal signo = GDB_SIGNAL_0; |
1564 | ||
8817a6f2 PA |
1565 | if (lp == except) |
1566 | return 0; | |
1567 | ||
e5ef252a PA |
1568 | if (lp->stopped) |
1569 | { | |
1570 | struct thread_info *thread; | |
1571 | ||
1572 | thread = find_thread_ptid (lp->ptid); | |
1573 | if (thread != NULL) | |
1574 | { | |
70509625 | 1575 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1576 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1577 | } | |
1578 | } | |
1579 | ||
1580 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1581 | return 0; |
1582 | } | |
1583 | ||
1584 | static int | |
1585 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1586 | { | |
1587 | lp->resumed = 0; | |
25289eb2 | 1588 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1589 | return 0; |
1590 | } | |
1591 | ||
1592 | static int | |
1593 | resume_set_callback (struct lwp_info *lp, void *data) | |
1594 | { | |
1595 | lp->resumed = 1; | |
25289eb2 | 1596 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1597 | return 0; |
1598 | } | |
1599 | ||
1600 | static void | |
28439f5e | 1601 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1602 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1603 | { |
1604 | struct lwp_info *lp; | |
d90e17a7 | 1605 | int resume_many; |
d6b0e80f | 1606 | |
76f50ad1 DJ |
1607 | if (debug_linux_nat) |
1608 | fprintf_unfiltered (gdb_stdlog, | |
1609 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1610 | step ? "step" : "resume", | |
1611 | target_pid_to_str (ptid), | |
a493e3e2 | 1612 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1613 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1614 | target_pid_to_str (inferior_ptid)); |
1615 | ||
d6b0e80f | 1616 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1617 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1618 | || ptid_is_pid (ptid)); | |
4c28f408 | 1619 | |
e3e9f5a2 PA |
1620 | /* Mark the lwps we're resuming as resumed. */ |
1621 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1622 | |
d90e17a7 PA |
1623 | /* See if it's the current inferior that should be handled |
1624 | specially. */ | |
1625 | if (resume_many) | |
1626 | lp = find_lwp_pid (inferior_ptid); | |
1627 | else | |
1628 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1629 | gdb_assert (lp != NULL); |
d6b0e80f | 1630 | |
9f0bdab8 | 1631 | /* Remember if we're stepping. */ |
25289eb2 | 1632 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1633 | |
9f0bdab8 DJ |
1634 | /* If we have a pending wait status for this thread, there is no |
1635 | point in resuming the process. But first make sure that | |
1636 | linux_nat_wait won't preemptively handle the event - we | |
1637 | should never take this short-circuit if we are going to | |
1638 | leave LP running, since we have skipped resuming all the | |
1639 | other threads. This bit of code needs to be synchronized | |
1640 | with linux_nat_wait. */ | |
76f50ad1 | 1641 | |
9f0bdab8 DJ |
1642 | if (lp->status && WIFSTOPPED (lp->status)) |
1643 | { | |
2455069d UW |
1644 | if (!lp->step |
1645 | && WSTOPSIG (lp->status) | |
1646 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1647 | { |
9f0bdab8 DJ |
1648 | if (debug_linux_nat) |
1649 | fprintf_unfiltered (gdb_stdlog, | |
1650 | "LLR: Not short circuiting for ignored " | |
1651 | "status 0x%x\n", lp->status); | |
1652 | ||
d6b0e80f AC |
1653 | /* FIXME: What should we do if we are supposed to continue |
1654 | this thread with a signal? */ | |
a493e3e2 | 1655 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1656 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1657 | lp->status = 0; |
1658 | } | |
1659 | } | |
76f50ad1 | 1660 | |
8a99810d | 1661 | if (lwp_status_pending_p (lp)) |
9f0bdab8 DJ |
1662 | { |
1663 | /* FIXME: What should we do if we are supposed to continue | |
1664 | this thread with a signal? */ | |
a493e3e2 | 1665 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1666 | |
9f0bdab8 DJ |
1667 | if (debug_linux_nat) |
1668 | fprintf_unfiltered (gdb_stdlog, | |
1669 | "LLR: Short circuiting for status 0x%x\n", | |
1670 | lp->status); | |
d6b0e80f | 1671 | |
7feb7d06 PA |
1672 | if (target_can_async_p ()) |
1673 | { | |
6a3753b3 | 1674 | target_async (1); |
7feb7d06 PA |
1675 | /* Tell the event loop we have something to process. */ |
1676 | async_file_mark (); | |
1677 | } | |
9f0bdab8 | 1678 | return; |
d6b0e80f AC |
1679 | } |
1680 | ||
d90e17a7 | 1681 | if (resume_many) |
8817a6f2 | 1682 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 | 1683 | |
d6b0e80f AC |
1684 | if (debug_linux_nat) |
1685 | fprintf_unfiltered (gdb_stdlog, | |
1686 | "LLR: %s %s, %s (resume event thread)\n", | |
1687 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2bf6fb9d | 1688 | target_pid_to_str (lp->ptid), |
a493e3e2 | 1689 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1690 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 | 1691 | |
2bf6fb9d PA |
1692 | linux_resume_one_lwp (lp, step, signo); |
1693 | ||
b84876c2 | 1694 | if (target_can_async_p ()) |
6a3753b3 | 1695 | target_async (1); |
d6b0e80f AC |
1696 | } |
1697 | ||
c5f62d5f | 1698 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1699 | |
1700 | static int | |
1701 | kill_lwp (int lwpid, int signo) | |
1702 | { | |
c5f62d5f DE |
1703 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1704 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1705 | |
1706 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1707 | { |
1708 | static int tkill_failed; | |
1709 | ||
1710 | if (!tkill_failed) | |
1711 | { | |
1712 | int ret; | |
1713 | ||
1714 | errno = 0; | |
1715 | ret = syscall (__NR_tkill, lwpid, signo); | |
1716 | if (errno != ENOSYS) | |
1717 | return ret; | |
1718 | tkill_failed = 1; | |
1719 | } | |
1720 | } | |
d6b0e80f AC |
1721 | #endif |
1722 | ||
1723 | return kill (lwpid, signo); | |
1724 | } | |
1725 | ||
ca2163eb PA |
1726 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1727 | event, check if the core is interested in it: if not, ignore the | |
1728 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1729 | syscall entry/exit status, since the ptrace event itself doesn't | |
1730 | indicate it, and report the trap to higher layers. */ | |
1731 | ||
1732 | static int | |
1733 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1734 | { | |
1735 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1736 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1737 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1738 | ||
1739 | if (stopping) | |
1740 | { | |
1741 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1742 | makes it so that the LWP reports an immediate syscall return, | |
1743 | followed by the SIGSTOP. Skip seeing that "return" using | |
1744 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1745 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1746 | entry event. If we didn't do this (and returned 0), we'd | |
1747 | leave a syscall entry pending, and our caller, by using | |
1748 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1749 | itself. Later, when the user re-resumes this LWP, we'd see | |
1750 | another syscall entry event and we'd mistake it for a return. | |
1751 | ||
1752 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1753 | (leaving immediately with LWP->signalled set, without issuing | |
1754 | a PTRACE_CONT), it would still be problematic to leave this | |
1755 | syscall enter pending, as later when the thread is resumed, | |
1756 | it would then see the same syscall exit mentioned above, | |
1757 | followed by the delayed SIGSTOP, while the syscall didn't | |
1758 | actually get to execute. It seems it would be even more | |
1759 | confusing to the user. */ | |
1760 | ||
1761 | if (debug_linux_nat) | |
1762 | fprintf_unfiltered (gdb_stdlog, | |
1763 | "LHST: ignoring syscall %d " | |
1764 | "for LWP %ld (stopping threads), " | |
1765 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1766 | syscall_number, | |
dfd4cc63 | 1767 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1768 | |
1769 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1770 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1771 | lp->stopped = 0; |
ca2163eb PA |
1772 | return 1; |
1773 | } | |
1774 | ||
bfd09d20 JS |
1775 | /* Always update the entry/return state, even if this particular |
1776 | syscall isn't interesting to the core now. In async mode, | |
1777 | the user could install a new catchpoint for this syscall | |
1778 | between syscall enter/return, and we'll need to know to | |
1779 | report a syscall return if that happens. */ | |
1780 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1781 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1782 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1783 | ||
ca2163eb PA |
1784 | if (catch_syscall_enabled ()) |
1785 | { | |
ca2163eb PA |
1786 | if (catching_syscall_number (syscall_number)) |
1787 | { | |
1788 | /* Alright, an event to report. */ | |
1789 | ourstatus->kind = lp->syscall_state; | |
1790 | ourstatus->value.syscall_number = syscall_number; | |
1791 | ||
1792 | if (debug_linux_nat) | |
1793 | fprintf_unfiltered (gdb_stdlog, | |
1794 | "LHST: stopping for %s of syscall %d" | |
1795 | " for LWP %ld\n", | |
3e43a32a MS |
1796 | lp->syscall_state |
1797 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1798 | ? "entry" : "return", |
1799 | syscall_number, | |
dfd4cc63 | 1800 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1801 | return 0; |
1802 | } | |
1803 | ||
1804 | if (debug_linux_nat) | |
1805 | fprintf_unfiltered (gdb_stdlog, | |
1806 | "LHST: ignoring %s of syscall %d " | |
1807 | "for LWP %ld\n", | |
1808 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1809 | ? "entry" : "return", | |
1810 | syscall_number, | |
dfd4cc63 | 1811 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1812 | } |
1813 | else | |
1814 | { | |
1815 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1816 | before on this LWP, it could happen that the user removes all | |
1817 | syscall catchpoints before we get to process this event. | |
1818 | There are two noteworthy issues here: | |
1819 | ||
1820 | - When stopped at a syscall entry event, resuming with | |
1821 | PT_STEP still resumes executing the syscall and reports a | |
1822 | syscall return. | |
1823 | ||
1824 | - Only PT_SYSCALL catches syscall enters. If we last | |
1825 | single-stepped this thread, then this event can't be a | |
1826 | syscall enter. If we last single-stepped this thread, this | |
1827 | has to be a syscall exit. | |
1828 | ||
1829 | The points above mean that the next resume, be it PT_STEP or | |
1830 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1831 | if (debug_linux_nat) | |
1832 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1833 | "LHST: caught syscall event " |
1834 | "with no syscall catchpoints." | |
ca2163eb PA |
1835 | " %d for LWP %ld, ignoring\n", |
1836 | syscall_number, | |
dfd4cc63 | 1837 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1838 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1839 | } | |
1840 | ||
1841 | /* The core isn't interested in this event. For efficiency, avoid | |
1842 | stopping all threads only to have the core resume them all again. | |
1843 | Since we're not stopping threads, if we're still syscall tracing | |
1844 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1845 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1846 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1847 | ||
8a99810d | 1848 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1849 | return 1; |
1850 | } | |
1851 | ||
3d799a95 DJ |
1852 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1853 | event, we need to add the new LWP to our list (and not report the | |
1854 | trap to higher layers). This function returns non-zero if the | |
1855 | event should be ignored and we should wait again. If STOPPING is | |
1856 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1857 | |
1858 | static int | |
4dd63d48 | 1859 | linux_handle_extended_wait (struct lwp_info *lp, int status) |
d6b0e80f | 1860 | { |
dfd4cc63 | 1861 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1862 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
89a5711c | 1863 | int event = linux_ptrace_get_extended_event (status); |
d6b0e80f | 1864 | |
bfd09d20 JS |
1865 | /* All extended events we currently use are mid-syscall. Only |
1866 | PTRACE_EVENT_STOP is delivered more like a signal-stop, but | |
1867 | you have to be using PTRACE_SEIZE to get that. */ | |
1868 | lp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY; | |
1869 | ||
3d799a95 DJ |
1870 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1871 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1872 | { |
3d799a95 DJ |
1873 | unsigned long new_pid; |
1874 | int ret; | |
1875 | ||
1876 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1877 | |
3d799a95 DJ |
1878 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1879 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1880 | { | |
1881 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1882 | hits the SIGSTOP, but we're already attached. */ | |
1883 | ret = my_waitpid (new_pid, &status, | |
1884 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
1885 | if (ret == -1) | |
1886 | perror_with_name (_("waiting for new child")); | |
1887 | else if (ret != new_pid) | |
1888 | internal_error (__FILE__, __LINE__, | |
1889 | _("wait returned unexpected PID %d"), ret); | |
1890 | else if (!WIFSTOPPED (status)) | |
1891 | internal_error (__FILE__, __LINE__, | |
1892 | _("wait returned unexpected status 0x%x"), status); | |
1893 | } | |
1894 | ||
3a3e9ee3 | 1895 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 1896 | |
26cb8b7c PA |
1897 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
1898 | { | |
1899 | /* The arch-specific native code may need to know about new | |
1900 | forks even if those end up never mapped to an | |
1901 | inferior. */ | |
1902 | if (linux_nat_new_fork != NULL) | |
1903 | linux_nat_new_fork (lp, new_pid); | |
1904 | } | |
1905 | ||
2277426b | 1906 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 1907 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 1908 | { |
2277426b PA |
1909 | /* Handle checkpointing by linux-fork.c here as a special |
1910 | case. We don't want the follow-fork-mode or 'catch fork' | |
1911 | to interfere with this. */ | |
1912 | ||
1913 | /* This won't actually modify the breakpoint list, but will | |
1914 | physically remove the breakpoints from the child. */ | |
d80ee84f | 1915 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
1916 | |
1917 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
1918 | if (!find_fork_pid (new_pid)) |
1919 | add_fork (new_pid); | |
2277426b PA |
1920 | |
1921 | /* Report as spurious, so that infrun doesn't want to follow | |
1922 | this fork. We're actually doing an infcall in | |
1923 | linux-fork.c. */ | |
1924 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
1925 | |
1926 | /* Report the stop to the core. */ | |
1927 | return 0; | |
1928 | } | |
1929 | ||
3d799a95 DJ |
1930 | if (event == PTRACE_EVENT_FORK) |
1931 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
1932 | else if (event == PTRACE_EVENT_VFORK) | |
1933 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
4dd63d48 | 1934 | else if (event == PTRACE_EVENT_CLONE) |
3d799a95 | 1935 | { |
78768c4a JK |
1936 | struct lwp_info *new_lp; |
1937 | ||
3d799a95 | 1938 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 1939 | |
3c4d7e12 PA |
1940 | if (debug_linux_nat) |
1941 | fprintf_unfiltered (gdb_stdlog, | |
1942 | "LHEW: Got clone event " | |
1943 | "from LWP %d, new child is LWP %ld\n", | |
1944 | pid, new_pid); | |
1945 | ||
dfd4cc63 | 1946 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 1947 | new_lp->cloned = 1; |
4c28f408 | 1948 | new_lp->stopped = 1; |
4dd63d48 | 1949 | new_lp->resumed = 1; |
d6b0e80f | 1950 | |
2db9a427 PA |
1951 | /* If the thread_db layer is active, let it record the user |
1952 | level thread id and status, and add the thread to GDB's | |
1953 | list. */ | |
1954 | if (!thread_db_notice_clone (lp->ptid, new_lp->ptid)) | |
3d799a95 | 1955 | { |
2db9a427 PA |
1956 | /* The process is not using thread_db. Add the LWP to |
1957 | GDB's list. */ | |
1958 | target_post_attach (ptid_get_lwp (new_lp->ptid)); | |
1959 | add_thread (new_lp->ptid); | |
1960 | } | |
4c28f408 | 1961 | |
2ee52aa4 | 1962 | /* Even if we're stopping the thread for some reason |
4dd63d48 PA |
1963 | internal to this module, from the perspective of infrun |
1964 | and the user/frontend, this new thread is running until | |
1965 | it next reports a stop. */ | |
2ee52aa4 | 1966 | set_running (new_lp->ptid, 1); |
4dd63d48 | 1967 | set_executing (new_lp->ptid, 1); |
4c28f408 | 1968 | |
4dd63d48 | 1969 | if (WSTOPSIG (status) != SIGSTOP) |
79395f92 | 1970 | { |
4dd63d48 PA |
1971 | /* This can happen if someone starts sending signals to |
1972 | the new thread before it gets a chance to run, which | |
1973 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
1974 | This is an unlikely case, and harder to handle for | |
1975 | fork / vfork than for clone, so we do not try - but | |
1976 | we handle it for clone events here. */ | |
1977 | ||
1978 | new_lp->signalled = 1; | |
1979 | ||
79395f92 PA |
1980 | /* We created NEW_LP so it cannot yet contain STATUS. */ |
1981 | gdb_assert (new_lp->status == 0); | |
1982 | ||
1983 | /* Save the wait status to report later. */ | |
1984 | if (debug_linux_nat) | |
1985 | fprintf_unfiltered (gdb_stdlog, | |
1986 | "LHEW: waitpid of new LWP %ld, " | |
1987 | "saving status %s\n", | |
dfd4cc63 | 1988 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
1989 | status_to_str (status)); |
1990 | new_lp->status = status; | |
1991 | } | |
1992 | ||
3d799a95 DJ |
1993 | return 1; |
1994 | } | |
1995 | ||
1996 | return 0; | |
d6b0e80f AC |
1997 | } |
1998 | ||
3d799a95 DJ |
1999 | if (event == PTRACE_EVENT_EXEC) |
2000 | { | |
a75724bc PA |
2001 | if (debug_linux_nat) |
2002 | fprintf_unfiltered (gdb_stdlog, | |
2003 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2004 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2005 | |
3d799a95 DJ |
2006 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2007 | ourstatus->value.execd_pathname | |
8dd27370 | 2008 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2009 | |
8af756ef PA |
2010 | /* The thread that execed must have been resumed, but, when a |
2011 | thread execs, it changes its tid to the tgid, and the old | |
2012 | tgid thread might have not been resumed. */ | |
2013 | lp->resumed = 1; | |
6c95b8df PA |
2014 | return 0; |
2015 | } | |
2016 | ||
2017 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2018 | { | |
2019 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2020 | { |
6c95b8df | 2021 | if (debug_linux_nat) |
3e43a32a MS |
2022 | fprintf_unfiltered (gdb_stdlog, |
2023 | "LHEW: Got expected PTRACE_EVENT_" | |
2024 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2025 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2026 | |
6c95b8df PA |
2027 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2028 | return 0; | |
3d799a95 DJ |
2029 | } |
2030 | ||
6c95b8df | 2031 | if (debug_linux_nat) |
3e43a32a MS |
2032 | fprintf_unfiltered (gdb_stdlog, |
2033 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
20ba1ce6 | 2034 | "from LWP %ld: ignoring\n", |
dfd4cc63 | 2035 | ptid_get_lwp (lp->ptid)); |
6c95b8df | 2036 | return 1; |
3d799a95 DJ |
2037 | } |
2038 | ||
2039 | internal_error (__FILE__, __LINE__, | |
2040 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2041 | } |
2042 | ||
2043 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2044 | exited. */ | |
2045 | ||
2046 | static int | |
2047 | wait_lwp (struct lwp_info *lp) | |
2048 | { | |
2049 | pid_t pid; | |
432b4d03 | 2050 | int status = 0; |
d6b0e80f | 2051 | int thread_dead = 0; |
432b4d03 | 2052 | sigset_t prev_mask; |
d6b0e80f AC |
2053 | |
2054 | gdb_assert (!lp->stopped); | |
2055 | gdb_assert (lp->status == 0); | |
2056 | ||
432b4d03 JK |
2057 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2058 | block_child_signals (&prev_mask); | |
2059 | ||
2060 | for (;;) | |
d6b0e80f | 2061 | { |
432b4d03 JK |
2062 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2063 | was right and we should just call sigsuspend. */ | |
2064 | ||
dfd4cc63 | 2065 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2066 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2067 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2068 | if (pid == -1 && errno == ECHILD) |
2069 | { | |
2070 | /* The thread has previously exited. We need to delete it | |
2071 | now because, for some vendor 2.4 kernels with NPTL | |
2072 | support backported, there won't be an exit event unless | |
2073 | it is the main thread. 2.6 kernels will report an exit | |
2074 | event for each thread that exits, as expected. */ | |
2075 | thread_dead = 1; | |
2076 | if (debug_linux_nat) | |
2077 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2078 | target_pid_to_str (lp->ptid)); | |
2079 | } | |
432b4d03 JK |
2080 | if (pid != 0) |
2081 | break; | |
2082 | ||
2083 | /* Bugs 10970, 12702. | |
2084 | Thread group leader may have exited in which case we'll lock up in | |
2085 | waitpid if there are other threads, even if they are all zombies too. | |
2086 | Basically, we're not supposed to use waitpid this way. | |
2087 | __WCLONE is not applicable for the leader so we can't use that. | |
2088 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2089 | process; it gets ESRCH both for the zombie and for running processes. | |
2090 | ||
2091 | As a workaround, check if we're waiting for the thread group leader and | |
2092 | if it's a zombie, and avoid calling waitpid if it is. | |
2093 | ||
2094 | This is racy, what if the tgl becomes a zombie right after we check? | |
2095 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2096 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2097 | |
dfd4cc63 LM |
2098 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2099 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2100 | { |
d6b0e80f AC |
2101 | thread_dead = 1; |
2102 | if (debug_linux_nat) | |
432b4d03 JK |
2103 | fprintf_unfiltered (gdb_stdlog, |
2104 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2105 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2106 | break; |
d6b0e80f | 2107 | } |
432b4d03 JK |
2108 | |
2109 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2110 | get invoked despite our caller had them intentionally blocked by | |
2111 | block_child_signals. This is sensitive only to the loop of | |
2112 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2113 | again before it gets to sigsuspend so we can safely let the handlers | |
2114 | get executed here. */ | |
2115 | ||
d36bf488 DE |
2116 | if (debug_linux_nat) |
2117 | fprintf_unfiltered (gdb_stdlog, "WL: about to sigsuspend\n"); | |
432b4d03 JK |
2118 | sigsuspend (&suspend_mask); |
2119 | } | |
2120 | ||
2121 | restore_child_signals_mask (&prev_mask); | |
2122 | ||
d6b0e80f AC |
2123 | if (!thread_dead) |
2124 | { | |
dfd4cc63 | 2125 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2126 | |
2127 | if (debug_linux_nat) | |
2128 | { | |
2129 | fprintf_unfiltered (gdb_stdlog, | |
2130 | "WL: waitpid %s received %s\n", | |
2131 | target_pid_to_str (lp->ptid), | |
2132 | status_to_str (status)); | |
2133 | } | |
d6b0e80f | 2134 | |
a9f4bb21 PA |
2135 | /* Check if the thread has exited. */ |
2136 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2137 | { | |
69dde7dc PA |
2138 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
2139 | { | |
2140 | if (debug_linux_nat) | |
2141 | fprintf_unfiltered (gdb_stdlog, "WL: Process %d exited.\n", | |
2142 | ptid_get_pid (lp->ptid)); | |
2143 | ||
2144 | /* This is the leader exiting, it means the whole | |
2145 | process is gone. Store the status to report to the | |
2146 | core. Store it in lp->waitstatus, because lp->status | |
2147 | would be ambiguous (W_EXITCODE(0,0) == 0). */ | |
2148 | store_waitstatus (&lp->waitstatus, status); | |
2149 | return 0; | |
2150 | } | |
2151 | ||
a9f4bb21 PA |
2152 | thread_dead = 1; |
2153 | if (debug_linux_nat) | |
2154 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2155 | target_pid_to_str (lp->ptid)); | |
2156 | } | |
d6b0e80f AC |
2157 | } |
2158 | ||
2159 | if (thread_dead) | |
2160 | { | |
e26af52f | 2161 | exit_lwp (lp); |
d6b0e80f AC |
2162 | return 0; |
2163 | } | |
2164 | ||
2165 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2166 | lp->stopped = 1; |
d6b0e80f | 2167 | |
8784d563 PA |
2168 | if (lp->must_set_ptrace_flags) |
2169 | { | |
2170 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
de0d863e | 2171 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2172 | |
de0d863e | 2173 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), options); |
8784d563 PA |
2174 | lp->must_set_ptrace_flags = 0; |
2175 | } | |
2176 | ||
ca2163eb PA |
2177 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2178 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2179 | { | |
2180 | /* No longer need the sysgood bit. The ptrace event ends up | |
2181 | recorded in lp->waitstatus if we care for it. We can carry | |
2182 | on handling the event like a regular SIGTRAP from here | |
2183 | on. */ | |
2184 | status = W_STOPCODE (SIGTRAP); | |
2185 | if (linux_handle_syscall_trap (lp, 1)) | |
2186 | return wait_lwp (lp); | |
2187 | } | |
bfd09d20 JS |
2188 | else |
2189 | { | |
2190 | /* Almost all other ptrace-stops are known to be outside of system | |
2191 | calls, with further exceptions in linux_handle_extended_wait. */ | |
2192 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
2193 | } | |
ca2163eb | 2194 | |
d6b0e80f | 2195 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
2196 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
2197 | && linux_is_extended_waitstatus (status)) | |
d6b0e80f AC |
2198 | { |
2199 | if (debug_linux_nat) | |
2200 | fprintf_unfiltered (gdb_stdlog, | |
2201 | "WL: Handling extended status 0x%06x\n", | |
2202 | status); | |
4dd63d48 | 2203 | linux_handle_extended_wait (lp, status); |
20ba1ce6 | 2204 | return 0; |
d6b0e80f AC |
2205 | } |
2206 | ||
2207 | return status; | |
2208 | } | |
2209 | ||
2210 | /* Send a SIGSTOP to LP. */ | |
2211 | ||
2212 | static int | |
2213 | stop_callback (struct lwp_info *lp, void *data) | |
2214 | { | |
2215 | if (!lp->stopped && !lp->signalled) | |
2216 | { | |
2217 | int ret; | |
2218 | ||
2219 | if (debug_linux_nat) | |
2220 | { | |
2221 | fprintf_unfiltered (gdb_stdlog, | |
2222 | "SC: kill %s **<SIGSTOP>**\n", | |
2223 | target_pid_to_str (lp->ptid)); | |
2224 | } | |
2225 | errno = 0; | |
dfd4cc63 | 2226 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2227 | if (debug_linux_nat) |
2228 | { | |
2229 | fprintf_unfiltered (gdb_stdlog, | |
2230 | "SC: lwp kill %d %s\n", | |
2231 | ret, | |
2232 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2233 | } | |
2234 | ||
2235 | lp->signalled = 1; | |
2236 | gdb_assert (lp->status == 0); | |
2237 | } | |
2238 | ||
2239 | return 0; | |
2240 | } | |
2241 | ||
7b50312a PA |
2242 | /* Request a stop on LWP. */ |
2243 | ||
2244 | void | |
2245 | linux_stop_lwp (struct lwp_info *lwp) | |
2246 | { | |
2247 | stop_callback (lwp, NULL); | |
2248 | } | |
2249 | ||
2db9a427 PA |
2250 | /* See linux-nat.h */ |
2251 | ||
2252 | void | |
2253 | linux_stop_and_wait_all_lwps (void) | |
2254 | { | |
2255 | /* Stop all LWP's ... */ | |
2256 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); | |
2257 | ||
2258 | /* ... and wait until all of them have reported back that | |
2259 | they're no longer running. */ | |
2260 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); | |
2261 | } | |
2262 | ||
2263 | /* See linux-nat.h */ | |
2264 | ||
2265 | void | |
2266 | linux_unstop_all_lwps (void) | |
2267 | { | |
2268 | iterate_over_lwps (minus_one_ptid, | |
2269 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
2270 | } | |
2271 | ||
57380f4e | 2272 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2273 | |
2274 | static int | |
57380f4e DJ |
2275 | linux_nat_has_pending_sigint (int pid) |
2276 | { | |
2277 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2278 | |
2279 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2280 | ||
2281 | if (sigismember (&pending, SIGINT) | |
2282 | && !sigismember (&ignored, SIGINT)) | |
2283 | return 1; | |
2284 | ||
2285 | return 0; | |
2286 | } | |
2287 | ||
2288 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2289 | ||
2290 | static int | |
2291 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2292 | { |
57380f4e DJ |
2293 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2294 | flag to consume the next one. */ | |
2295 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2296 | && WSTOPSIG (lp->status) == SIGINT) | |
2297 | lp->status = 0; | |
2298 | else | |
2299 | lp->ignore_sigint = 1; | |
2300 | ||
2301 | return 0; | |
2302 | } | |
2303 | ||
2304 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2305 | This function is called after we know the LWP has stopped; if the LWP | |
2306 | stopped before the expected SIGINT was delivered, then it will never have | |
2307 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2308 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2309 | |
57380f4e DJ |
2310 | static void |
2311 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2312 | { | |
2313 | if (!lp->ignore_sigint) | |
2314 | return; | |
2315 | ||
dfd4cc63 | 2316 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2317 | { |
2318 | if (debug_linux_nat) | |
2319 | fprintf_unfiltered (gdb_stdlog, | |
2320 | "MCIS: Clearing bogus flag for %s\n", | |
2321 | target_pid_to_str (lp->ptid)); | |
2322 | lp->ignore_sigint = 0; | |
2323 | } | |
2324 | } | |
2325 | ||
ebec9a0f PA |
2326 | /* Fetch the possible triggered data watchpoint info and store it in |
2327 | LP. | |
2328 | ||
2329 | On some archs, like x86, that use debug registers to set | |
2330 | watchpoints, it's possible that the way to know which watched | |
2331 | address trapped, is to check the register that is used to select | |
2332 | which address to watch. Problem is, between setting the watchpoint | |
2333 | and reading back which data address trapped, the user may change | |
2334 | the set of watchpoints, and, as a consequence, GDB changes the | |
2335 | debug registers in the inferior. To avoid reading back a stale | |
2336 | stopped-data-address when that happens, we cache in LP the fact | |
2337 | that a watchpoint trapped, and the corresponding data address, as | |
2338 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2339 | registers meanwhile, we have the cached data we can rely on. */ | |
2340 | ||
9c02b525 PA |
2341 | static int |
2342 | check_stopped_by_watchpoint (struct lwp_info *lp) | |
ebec9a0f PA |
2343 | { |
2344 | struct cleanup *old_chain; | |
2345 | ||
2346 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
9c02b525 | 2347 | return 0; |
ebec9a0f PA |
2348 | |
2349 | old_chain = save_inferior_ptid (); | |
2350 | inferior_ptid = lp->ptid; | |
2351 | ||
9c02b525 | 2352 | if (linux_ops->to_stopped_by_watchpoint (linux_ops)) |
ebec9a0f | 2353 | { |
15c66dd6 | 2354 | lp->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 | 2355 | |
ebec9a0f PA |
2356 | if (linux_ops->to_stopped_data_address != NULL) |
2357 | lp->stopped_data_address_p = | |
2358 | linux_ops->to_stopped_data_address (¤t_target, | |
2359 | &lp->stopped_data_address); | |
2360 | else | |
2361 | lp->stopped_data_address_p = 0; | |
2362 | } | |
2363 | ||
2364 | do_cleanups (old_chain); | |
9c02b525 | 2365 | |
15c66dd6 | 2366 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 PA |
2367 | } |
2368 | ||
2369 | /* Called when the LWP stopped for a trap that could be explained by a | |
2370 | watchpoint or a breakpoint. */ | |
2371 | ||
2372 | static void | |
2373 | save_sigtrap (struct lwp_info *lp) | |
2374 | { | |
15c66dd6 | 2375 | gdb_assert (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON); |
9c02b525 PA |
2376 | gdb_assert (lp->status != 0); |
2377 | ||
faf09f01 PA |
2378 | /* Check first if this was a SW/HW breakpoint before checking |
2379 | watchpoints, because at least s390 can't tell the data address of | |
2380 | hardware watchpoint hits, and the kernel returns | |
2381 | stopped-by-watchpoint as long as there's a watchpoint set. */ | |
9c02b525 PA |
2382 | if (linux_nat_status_is_event (lp->status)) |
2383 | check_stopped_by_breakpoint (lp); | |
faf09f01 PA |
2384 | |
2385 | /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint | |
2386 | or hardware watchpoint. Check which is which if we got | |
2387 | TARGET_STOPPED_BY_HW_BREAKPOINT. */ | |
2388 | if (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON | |
2389 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
2390 | check_stopped_by_watchpoint (lp); | |
ebec9a0f PA |
2391 | } |
2392 | ||
9c02b525 | 2393 | /* Returns true if the LWP had stopped for a watchpoint. */ |
ebec9a0f PA |
2394 | |
2395 | static int | |
6a109b6b | 2396 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2397 | { |
2398 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2399 | ||
2400 | gdb_assert (lp != NULL); | |
2401 | ||
15c66dd6 | 2402 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
ebec9a0f PA |
2403 | } |
2404 | ||
2405 | static int | |
2406 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2407 | { | |
2408 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2409 | ||
2410 | gdb_assert (lp != NULL); | |
2411 | ||
2412 | *addr_p = lp->stopped_data_address; | |
2413 | ||
2414 | return lp->stopped_data_address_p; | |
2415 | } | |
2416 | ||
26ab7092 JK |
2417 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2418 | ||
2419 | static int | |
2420 | sigtrap_is_event (int status) | |
2421 | { | |
2422 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2423 | } | |
2424 | ||
26ab7092 JK |
2425 | /* Set alternative SIGTRAP-like events recognizer. If |
2426 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2427 | applied. */ | |
2428 | ||
2429 | void | |
2430 | linux_nat_set_status_is_event (struct target_ops *t, | |
2431 | int (*status_is_event) (int status)) | |
2432 | { | |
2433 | linux_nat_status_is_event = status_is_event; | |
2434 | } | |
2435 | ||
57380f4e DJ |
2436 | /* Wait until LP is stopped. */ |
2437 | ||
2438 | static int | |
2439 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2440 | { | |
c9657e70 | 2441 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
6c95b8df PA |
2442 | |
2443 | /* If this is a vfork parent, bail out, it is not going to report | |
2444 | any SIGSTOP until the vfork is done with. */ | |
2445 | if (inf->vfork_child != NULL) | |
2446 | return 0; | |
2447 | ||
d6b0e80f AC |
2448 | if (!lp->stopped) |
2449 | { | |
2450 | int status; | |
2451 | ||
2452 | status = wait_lwp (lp); | |
2453 | if (status == 0) | |
2454 | return 0; | |
2455 | ||
57380f4e DJ |
2456 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2457 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2458 | { |
57380f4e | 2459 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2460 | |
2461 | errno = 0; | |
dfd4cc63 | 2462 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2463 | lp->stopped = 0; |
d6b0e80f AC |
2464 | if (debug_linux_nat) |
2465 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2466 | "PTRACE_CONT %s, 0, 0 (%s) " |
2467 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2468 | target_pid_to_str (lp->ptid), |
2469 | errno ? safe_strerror (errno) : "OK"); | |
2470 | ||
57380f4e | 2471 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2472 | } |
2473 | ||
57380f4e DJ |
2474 | maybe_clear_ignore_sigint (lp); |
2475 | ||
d6b0e80f AC |
2476 | if (WSTOPSIG (status) != SIGSTOP) |
2477 | { | |
e5ef252a | 2478 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2479 | |
e5ef252a PA |
2480 | if (debug_linux_nat) |
2481 | fprintf_unfiltered (gdb_stdlog, | |
2482 | "SWC: Pending event %s in %s\n", | |
2483 | status_to_str ((int) status), | |
2484 | target_pid_to_str (lp->ptid)); | |
2485 | ||
2486 | /* Save the sigtrap event. */ | |
2487 | lp->status = status; | |
e5ef252a | 2488 | gdb_assert (lp->signalled); |
9c02b525 | 2489 | save_sigtrap (lp); |
d6b0e80f AC |
2490 | } |
2491 | else | |
2492 | { | |
2493 | /* We caught the SIGSTOP that we intended to catch, so | |
2494 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2495 | |
2496 | if (debug_linux_nat) | |
2497 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2498 | "SWC: Expected SIGSTOP caught for %s.\n", |
e5ef252a PA |
2499 | target_pid_to_str (lp->ptid)); |
2500 | ||
e5ef252a PA |
2501 | /* Reset SIGNALLED only after the stop_wait_callback call |
2502 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2503 | lp->signalled = 0; |
2504 | } | |
2505 | } | |
2506 | ||
2507 | return 0; | |
2508 | } | |
2509 | ||
9c02b525 PA |
2510 | /* Return non-zero if LP has a wait status pending. Discard the |
2511 | pending event and resume the LWP if the event that originally | |
2512 | caused the stop became uninteresting. */ | |
d6b0e80f AC |
2513 | |
2514 | static int | |
2515 | status_callback (struct lwp_info *lp, void *data) | |
2516 | { | |
2517 | /* Only report a pending wait status if we pretend that this has | |
2518 | indeed been resumed. */ | |
ca2163eb PA |
2519 | if (!lp->resumed) |
2520 | return 0; | |
2521 | ||
eb54c8bf PA |
2522 | if (!lwp_status_pending_p (lp)) |
2523 | return 0; | |
2524 | ||
15c66dd6 PA |
2525 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
2526 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
9c02b525 PA |
2527 | { |
2528 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
2529 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2530 | CORE_ADDR pc; | |
2531 | int discard = 0; | |
2532 | ||
9c02b525 PA |
2533 | pc = regcache_read_pc (regcache); |
2534 | ||
2535 | if (pc != lp->stop_pc) | |
2536 | { | |
2537 | if (debug_linux_nat) | |
2538 | fprintf_unfiltered (gdb_stdlog, | |
2539 | "SC: PC of %s changed. was=%s, now=%s\n", | |
2540 | target_pid_to_str (lp->ptid), | |
2541 | paddress (target_gdbarch (), lp->stop_pc), | |
2542 | paddress (target_gdbarch (), pc)); | |
2543 | discard = 1; | |
2544 | } | |
faf09f01 PA |
2545 | |
2546 | #if !USE_SIGTRAP_SIGINFO | |
9c02b525 PA |
2547 | else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2548 | { | |
2549 | if (debug_linux_nat) | |
2550 | fprintf_unfiltered (gdb_stdlog, | |
2551 | "SC: previous breakpoint of %s, at %s gone\n", | |
2552 | target_pid_to_str (lp->ptid), | |
2553 | paddress (target_gdbarch (), lp->stop_pc)); | |
2554 | ||
2555 | discard = 1; | |
2556 | } | |
faf09f01 | 2557 | #endif |
9c02b525 PA |
2558 | |
2559 | if (discard) | |
2560 | { | |
2561 | if (debug_linux_nat) | |
2562 | fprintf_unfiltered (gdb_stdlog, | |
2563 | "SC: pending event of %s cancelled.\n", | |
2564 | target_pid_to_str (lp->ptid)); | |
2565 | ||
2566 | lp->status = 0; | |
2567 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); | |
2568 | return 0; | |
2569 | } | |
9c02b525 PA |
2570 | } |
2571 | ||
eb54c8bf | 2572 | return 1; |
d6b0e80f AC |
2573 | } |
2574 | ||
2575 | /* Return non-zero if LP isn't stopped. */ | |
2576 | ||
2577 | static int | |
2578 | running_callback (struct lwp_info *lp, void *data) | |
2579 | { | |
25289eb2 | 2580 | return (!lp->stopped |
8a99810d | 2581 | || (lwp_status_pending_p (lp) && lp->resumed)); |
d6b0e80f AC |
2582 | } |
2583 | ||
2584 | /* Count the LWP's that have had events. */ | |
2585 | ||
2586 | static int | |
2587 | count_events_callback (struct lwp_info *lp, void *data) | |
2588 | { | |
9a3c8263 | 2589 | int *count = (int *) data; |
d6b0e80f AC |
2590 | |
2591 | gdb_assert (count != NULL); | |
2592 | ||
9c02b525 PA |
2593 | /* Select only resumed LWPs that have an event pending. */ |
2594 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2595 | (*count)++; |
2596 | ||
2597 | return 0; | |
2598 | } | |
2599 | ||
2600 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2601 | ||
2602 | static int | |
2603 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2604 | { | |
25289eb2 PA |
2605 | if (lp->last_resume_kind == resume_step |
2606 | && lp->status != 0) | |
d6b0e80f AC |
2607 | return 1; |
2608 | else | |
2609 | return 0; | |
2610 | } | |
2611 | ||
8a99810d PA |
2612 | /* Returns true if LP has a status pending. */ |
2613 | ||
2614 | static int | |
2615 | lwp_status_pending_p (struct lwp_info *lp) | |
2616 | { | |
2617 | /* We check for lp->waitstatus in addition to lp->status, because we | |
2618 | can have pending process exits recorded in lp->status and | |
2619 | W_EXITCODE(0,0) happens to be 0. */ | |
2620 | return lp->status != 0 || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE; | |
2621 | } | |
2622 | ||
b90fc188 | 2623 | /* Select the Nth LWP that has had an event. */ |
d6b0e80f AC |
2624 | |
2625 | static int | |
2626 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2627 | { | |
9a3c8263 | 2628 | int *selector = (int *) data; |
d6b0e80f AC |
2629 | |
2630 | gdb_assert (selector != NULL); | |
2631 | ||
9c02b525 PA |
2632 | /* Select only resumed LWPs that have an event pending. */ |
2633 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2634 | if ((*selector)-- == 0) |
2635 | return 1; | |
2636 | ||
2637 | return 0; | |
2638 | } | |
2639 | ||
9c02b525 PA |
2640 | /* Called when the LWP got a signal/trap that could be explained by a |
2641 | software or hardware breakpoint. */ | |
2642 | ||
710151dd | 2643 | static int |
9c02b525 | 2644 | check_stopped_by_breakpoint (struct lwp_info *lp) |
710151dd PA |
2645 | { |
2646 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2647 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2648 | LWP. We will handle the current event, eventually we will resume | |
2649 | this LWP, and this breakpoint will trap again. | |
2650 | ||
2651 | If we do not do this, then we run the risk that the user will | |
2652 | delete or disable the breakpoint, but the LWP will have already | |
2653 | tripped on it. */ | |
2654 | ||
515630c5 UW |
2655 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2656 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2657 | CORE_ADDR pc; | |
9c02b525 | 2658 | CORE_ADDR sw_bp_pc; |
faf09f01 PA |
2659 | #if USE_SIGTRAP_SIGINFO |
2660 | siginfo_t siginfo; | |
2661 | #endif | |
9c02b525 PA |
2662 | |
2663 | pc = regcache_read_pc (regcache); | |
527a273a | 2664 | sw_bp_pc = pc - gdbarch_decr_pc_after_break (gdbarch); |
515630c5 | 2665 | |
faf09f01 PA |
2666 | #if USE_SIGTRAP_SIGINFO |
2667 | if (linux_nat_get_siginfo (lp->ptid, &siginfo)) | |
2668 | { | |
2669 | if (siginfo.si_signo == SIGTRAP) | |
2670 | { | |
1db33b5a | 2671 | if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)) |
faf09f01 PA |
2672 | { |
2673 | if (debug_linux_nat) | |
2674 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d PA |
2675 | "CSBB: %s stopped by software " |
2676 | "breakpoint\n", | |
faf09f01 PA |
2677 | target_pid_to_str (lp->ptid)); |
2678 | ||
2679 | /* Back up the PC if necessary. */ | |
2680 | if (pc != sw_bp_pc) | |
2681 | regcache_write_pc (regcache, sw_bp_pc); | |
2682 | ||
2683 | lp->stop_pc = sw_bp_pc; | |
2684 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2685 | return 1; | |
2686 | } | |
2687 | else if (siginfo.si_code == TRAP_HWBKPT) | |
2688 | { | |
2689 | if (debug_linux_nat) | |
2690 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d PA |
2691 | "CSBB: %s stopped by hardware " |
2692 | "breakpoint/watchpoint\n", | |
faf09f01 PA |
2693 | target_pid_to_str (lp->ptid)); |
2694 | ||
2695 | lp->stop_pc = pc; | |
2696 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2697 | return 1; | |
2698 | } | |
2bf6fb9d PA |
2699 | else if (siginfo.si_code == TRAP_TRACE) |
2700 | { | |
2701 | if (debug_linux_nat) | |
2702 | fprintf_unfiltered (gdb_stdlog, | |
2703 | "CSBB: %s stopped by trace\n", | |
2704 | target_pid_to_str (lp->ptid)); | |
2705 | } | |
faf09f01 PA |
2706 | } |
2707 | } | |
2708 | #else | |
9c02b525 PA |
2709 | if ((!lp->step || lp->stop_pc == sw_bp_pc) |
2710 | && software_breakpoint_inserted_here_p (get_regcache_aspace (regcache), | |
2711 | sw_bp_pc)) | |
710151dd | 2712 | { |
9c02b525 PA |
2713 | /* The LWP was either continued, or stepped a software |
2714 | breakpoint instruction. */ | |
710151dd PA |
2715 | if (debug_linux_nat) |
2716 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2717 | "CSBB: %s stopped by software breakpoint\n", |
710151dd PA |
2718 | target_pid_to_str (lp->ptid)); |
2719 | ||
2720 | /* Back up the PC if necessary. */ | |
9c02b525 PA |
2721 | if (pc != sw_bp_pc) |
2722 | regcache_write_pc (regcache, sw_bp_pc); | |
515630c5 | 2723 | |
9c02b525 | 2724 | lp->stop_pc = sw_bp_pc; |
15c66dd6 | 2725 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
710151dd PA |
2726 | return 1; |
2727 | } | |
710151dd | 2728 | |
9c02b525 PA |
2729 | if (hardware_breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2730 | { | |
2731 | if (debug_linux_nat) | |
2732 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2733 | "CSBB: stopped by hardware breakpoint %s\n", |
9c02b525 | 2734 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 2735 | |
9c02b525 | 2736 | lp->stop_pc = pc; |
15c66dd6 | 2737 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; |
9c02b525 PA |
2738 | return 1; |
2739 | } | |
faf09f01 | 2740 | #endif |
d6b0e80f AC |
2741 | |
2742 | return 0; | |
2743 | } | |
2744 | ||
faf09f01 PA |
2745 | |
2746 | /* Returns true if the LWP had stopped for a software breakpoint. */ | |
2747 | ||
2748 | static int | |
2749 | linux_nat_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2750 | { | |
2751 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2752 | ||
2753 | gdb_assert (lp != NULL); | |
2754 | ||
2755 | return lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2756 | } | |
2757 | ||
2758 | /* Implement the supports_stopped_by_sw_breakpoint method. */ | |
2759 | ||
2760 | static int | |
2761 | linux_nat_supports_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2762 | { | |
2763 | return USE_SIGTRAP_SIGINFO; | |
2764 | } | |
2765 | ||
2766 | /* Returns true if the LWP had stopped for a hardware | |
2767 | breakpoint/watchpoint. */ | |
2768 | ||
2769 | static int | |
2770 | linux_nat_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2771 | { | |
2772 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2773 | ||
2774 | gdb_assert (lp != NULL); | |
2775 | ||
2776 | return lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2777 | } | |
2778 | ||
2779 | /* Implement the supports_stopped_by_hw_breakpoint method. */ | |
2780 | ||
2781 | static int | |
2782 | linux_nat_supports_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2783 | { | |
2784 | return USE_SIGTRAP_SIGINFO; | |
2785 | } | |
2786 | ||
d6b0e80f AC |
2787 | /* Select one LWP out of those that have events pending. */ |
2788 | ||
2789 | static void | |
d90e17a7 | 2790 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2791 | { |
2792 | int num_events = 0; | |
2793 | int random_selector; | |
9c02b525 | 2794 | struct lwp_info *event_lp = NULL; |
d6b0e80f | 2795 | |
ac264b3b | 2796 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2797 | (*orig_lp)->status = *status; |
2798 | ||
9c02b525 PA |
2799 | /* In all-stop, give preference to the LWP that is being |
2800 | single-stepped. There will be at most one, and it will be the | |
2801 | LWP that the core is most interested in. If we didn't do this, | |
2802 | then we'd have to handle pending step SIGTRAPs somehow in case | |
2803 | the core later continues the previously-stepped thread, as | |
2804 | otherwise we'd report the pending SIGTRAP then, and the core, not | |
2805 | having stepped the thread, wouldn't understand what the trap was | |
2806 | for, and therefore would report it to the user as a random | |
2807 | signal. */ | |
fbea99ea | 2808 | if (!target_is_non_stop_p ()) |
d6b0e80f | 2809 | { |
9c02b525 PA |
2810 | event_lp = iterate_over_lwps (filter, |
2811 | select_singlestep_lwp_callback, NULL); | |
2812 | if (event_lp != NULL) | |
2813 | { | |
2814 | if (debug_linux_nat) | |
2815 | fprintf_unfiltered (gdb_stdlog, | |
2816 | "SEL: Select single-step %s\n", | |
2817 | target_pid_to_str (event_lp->ptid)); | |
2818 | } | |
d6b0e80f | 2819 | } |
9c02b525 PA |
2820 | |
2821 | if (event_lp == NULL) | |
d6b0e80f | 2822 | { |
9c02b525 | 2823 | /* Pick one at random, out of those which have had events. */ |
d6b0e80f | 2824 | |
9c02b525 | 2825 | /* First see how many events we have. */ |
d90e17a7 | 2826 | iterate_over_lwps (filter, count_events_callback, &num_events); |
8bf3b159 | 2827 | gdb_assert (num_events > 0); |
d6b0e80f | 2828 | |
9c02b525 PA |
2829 | /* Now randomly pick a LWP out of those that have had |
2830 | events. */ | |
d6b0e80f AC |
2831 | random_selector = (int) |
2832 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2833 | ||
2834 | if (debug_linux_nat && num_events > 1) | |
2835 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2836 | "SEL: Found %d events, selecting #%d\n", |
d6b0e80f AC |
2837 | num_events, random_selector); |
2838 | ||
d90e17a7 PA |
2839 | event_lp = iterate_over_lwps (filter, |
2840 | select_event_lwp_callback, | |
d6b0e80f AC |
2841 | &random_selector); |
2842 | } | |
2843 | ||
2844 | if (event_lp != NULL) | |
2845 | { | |
2846 | /* Switch the event LWP. */ | |
2847 | *orig_lp = event_lp; | |
2848 | *status = event_lp->status; | |
2849 | } | |
2850 | ||
2851 | /* Flush the wait status for the event LWP. */ | |
2852 | (*orig_lp)->status = 0; | |
2853 | } | |
2854 | ||
2855 | /* Return non-zero if LP has been resumed. */ | |
2856 | ||
2857 | static int | |
2858 | resumed_callback (struct lwp_info *lp, void *data) | |
2859 | { | |
2860 | return lp->resumed; | |
2861 | } | |
2862 | ||
12d9289a PA |
2863 | /* Stop an active thread, verify it still exists, then resume it. If |
2864 | the thread ends up with a pending status, then it is not resumed, | |
2865 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2866 | |
2867 | static int | |
2868 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2869 | { | |
25289eb2 | 2870 | if (!lp->stopped) |
d6b0e80f | 2871 | { |
25289eb2 PA |
2872 | ptid_t ptid = lp->ptid; |
2873 | ||
d6b0e80f AC |
2874 | stop_callback (lp, NULL); |
2875 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2876 | |
2877 | /* Resume if the lwp still exists, and the core wanted it | |
2878 | running. */ | |
12d9289a PA |
2879 | lp = find_lwp_pid (ptid); |
2880 | if (lp != NULL) | |
25289eb2 | 2881 | { |
12d9289a | 2882 | if (lp->last_resume_kind == resume_stop |
8a99810d | 2883 | && !lwp_status_pending_p (lp)) |
12d9289a PA |
2884 | { |
2885 | /* The core wanted the LWP to stop. Even if it stopped | |
2886 | cleanly (with SIGSTOP), leave the event pending. */ | |
2887 | if (debug_linux_nat) | |
2888 | fprintf_unfiltered (gdb_stdlog, | |
2889 | "SARC: core wanted LWP %ld stopped " | |
2890 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2891 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2892 | lp->status = W_STOPCODE (SIGSTOP); |
2893 | } | |
2894 | ||
8a99810d | 2895 | if (!lwp_status_pending_p (lp)) |
12d9289a PA |
2896 | { |
2897 | if (debug_linux_nat) | |
2898 | fprintf_unfiltered (gdb_stdlog, | |
2899 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2900 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2901 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2902 | } |
2903 | else | |
2904 | { | |
2905 | if (debug_linux_nat) | |
2906 | fprintf_unfiltered (gdb_stdlog, | |
2907 | "SARC: not re-resuming LWP %ld " | |
2908 | "(has pending)\n", | |
dfd4cc63 | 2909 | ptid_get_lwp (lp->ptid)); |
12d9289a | 2910 | } |
25289eb2 | 2911 | } |
d6b0e80f AC |
2912 | } |
2913 | return 0; | |
2914 | } | |
2915 | ||
02f3fc28 | 2916 | /* Check if we should go on and pass this event to common code. |
9c02b525 | 2917 | Return the affected lwp if we are, or NULL otherwise. */ |
12d9289a | 2918 | |
02f3fc28 | 2919 | static struct lwp_info * |
9c02b525 | 2920 | linux_nat_filter_event (int lwpid, int status) |
02f3fc28 PA |
2921 | { |
2922 | struct lwp_info *lp; | |
89a5711c | 2923 | int event = linux_ptrace_get_extended_event (status); |
02f3fc28 PA |
2924 | |
2925 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
2926 | ||
2927 | /* Check for stop events reported by a process we didn't already | |
2928 | know about - anything not already in our LWP list. | |
2929 | ||
2930 | If we're expecting to receive stopped processes after | |
2931 | fork, vfork, and clone events, then we'll just add the | |
2932 | new one to our list and go back to waiting for the event | |
2933 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2934 | from waitpid before or after the event is. |
2935 | ||
2936 | But note the case of a non-leader thread exec'ing after the | |
2937 | leader having exited, and gone from our lists. The non-leader | |
2938 | thread changes its tid to the tgid. */ | |
2939 | ||
2940 | if (WIFSTOPPED (status) && lp == NULL | |
89a5711c | 2941 | && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC)) |
0e5bf2a8 PA |
2942 | { |
2943 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2944 | if (debug_linux_nat) | |
2945 | fprintf_unfiltered (gdb_stdlog, | |
2946 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2947 | lwpid); | |
2948 | ||
dfd4cc63 | 2949 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2950 | lp->stopped = 1; |
2951 | lp->resumed = 1; | |
2952 | add_thread (lp->ptid); | |
2953 | } | |
2954 | ||
02f3fc28 PA |
2955 | if (WIFSTOPPED (status) && !lp) |
2956 | { | |
3b27ef47 PA |
2957 | if (debug_linux_nat) |
2958 | fprintf_unfiltered (gdb_stdlog, | |
2959 | "LHEW: saving LWP %ld status %s in stopped_pids list\n", | |
2960 | (long) lwpid, status_to_str (status)); | |
84636d28 | 2961 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2962 | return NULL; |
2963 | } | |
2964 | ||
2965 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2966 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2967 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2968 | exits. */ |
2969 | if (!WIFSTOPPED (status) && !lp) | |
2970 | return NULL; | |
2971 | ||
8817a6f2 PA |
2972 | /* This LWP is stopped now. (And if dead, this prevents it from |
2973 | ever being continued.) */ | |
2974 | lp->stopped = 1; | |
2975 | ||
8784d563 PA |
2976 | if (WIFSTOPPED (status) && lp->must_set_ptrace_flags) |
2977 | { | |
2978 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
de0d863e | 2979 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2980 | |
de0d863e | 2981 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), options); |
8784d563 PA |
2982 | lp->must_set_ptrace_flags = 0; |
2983 | } | |
2984 | ||
ca2163eb PA |
2985 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2986 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2987 | { | |
2988 | /* No longer need the sysgood bit. The ptrace event ends up | |
2989 | recorded in lp->waitstatus if we care for it. We can carry | |
2990 | on handling the event like a regular SIGTRAP from here | |
2991 | on. */ | |
2992 | status = W_STOPCODE (SIGTRAP); | |
2993 | if (linux_handle_syscall_trap (lp, 0)) | |
2994 | return NULL; | |
2995 | } | |
bfd09d20 JS |
2996 | else |
2997 | { | |
2998 | /* Almost all other ptrace-stops are known to be outside of system | |
2999 | calls, with further exceptions in linux_handle_extended_wait. */ | |
3000 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
3001 | } | |
02f3fc28 | 3002 | |
ca2163eb | 3003 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
3004 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
3005 | && linux_is_extended_waitstatus (status)) | |
02f3fc28 PA |
3006 | { |
3007 | if (debug_linux_nat) | |
3008 | fprintf_unfiltered (gdb_stdlog, | |
3009 | "LLW: Handling extended status 0x%06x\n", | |
3010 | status); | |
4dd63d48 | 3011 | if (linux_handle_extended_wait (lp, status)) |
02f3fc28 PA |
3012 | return NULL; |
3013 | } | |
3014 | ||
3015 | /* Check if the thread has exited. */ | |
9c02b525 PA |
3016 | if (WIFEXITED (status) || WIFSIGNALED (status)) |
3017 | { | |
3018 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
02f3fc28 | 3019 | { |
9c02b525 PA |
3020 | /* If this is the main thread, we must stop all threads and |
3021 | verify if they are still alive. This is because in the | |
3022 | nptl thread model on Linux 2.4, there is no signal issued | |
3023 | for exiting LWPs other than the main thread. We only get | |
3024 | the main thread exit signal once all child threads have | |
3025 | already exited. If we stop all the threads and use the | |
3026 | stop_wait_callback to check if they have exited we can | |
3027 | determine whether this signal should be ignored or | |
3028 | whether it means the end of the debugged application, | |
3029 | regardless of which threading model is being used. */ | |
3030 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) | |
3031 | { | |
3032 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3033 | stop_and_resume_callback, NULL); | |
3034 | } | |
3035 | ||
3036 | if (debug_linux_nat) | |
3037 | fprintf_unfiltered (gdb_stdlog, | |
3038 | "LLW: %s exited.\n", | |
3039 | target_pid_to_str (lp->ptid)); | |
3040 | ||
3041 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
3042 | { | |
3043 | /* If there is at least one more LWP, then the exit signal | |
3044 | was not the end of the debugged application and should be | |
3045 | ignored. */ | |
3046 | exit_lwp (lp); | |
3047 | return NULL; | |
3048 | } | |
02f3fc28 PA |
3049 | } |
3050 | ||
77598427 PA |
3051 | /* Note that even if the leader was ptrace-stopped, it can still |
3052 | exit, if e.g., some other thread brings down the whole | |
3053 | process (calls `exit'). So don't assert that the lwp is | |
3054 | resumed. */ | |
02f3fc28 PA |
3055 | if (debug_linux_nat) |
3056 | fprintf_unfiltered (gdb_stdlog, | |
77598427 PA |
3057 | "Process %ld exited (resumed=%d)\n", |
3058 | ptid_get_lwp (lp->ptid), lp->resumed); | |
02f3fc28 | 3059 | |
9c02b525 PA |
3060 | /* This was the last lwp in the process. Since events are |
3061 | serialized to GDB core, we may not be able report this one | |
3062 | right now, but GDB core and the other target layers will want | |
3063 | to be notified about the exit code/signal, leave the status | |
3064 | pending for the next time we're able to report it. */ | |
3065 | ||
3066 | /* Dead LWP's aren't expected to reported a pending sigstop. */ | |
3067 | lp->signalled = 0; | |
3068 | ||
3069 | /* Store the pending event in the waitstatus, because | |
3070 | W_EXITCODE(0,0) == 0. */ | |
3071 | store_waitstatus (&lp->waitstatus, status); | |
3072 | return lp; | |
02f3fc28 PA |
3073 | } |
3074 | ||
3075 | /* Check if the current LWP has previously exited. In the nptl | |
3076 | thread model, LWPs other than the main thread do not issue | |
3077 | signals when they exit so we must check whenever the thread has | |
3078 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3079 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3080 | { |
dfd4cc63 | 3081 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3082 | |
02f3fc28 PA |
3083 | if (debug_linux_nat) |
3084 | fprintf_unfiltered (gdb_stdlog, | |
3085 | "LLW: %s exited.\n", | |
3086 | target_pid_to_str (lp->ptid)); | |
3087 | ||
3088 | exit_lwp (lp); | |
3089 | ||
3090 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3091 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3092 | |
3093 | /* Discard the event. */ | |
3094 | return NULL; | |
3095 | } | |
3096 | ||
3097 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3098 | an attempt to stop an LWP. */ | |
3099 | if (lp->signalled | |
3100 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3101 | { | |
02f3fc28 PA |
3102 | lp->signalled = 0; |
3103 | ||
2bf6fb9d | 3104 | if (lp->last_resume_kind == resume_stop) |
25289eb2 | 3105 | { |
2bf6fb9d PA |
3106 | if (debug_linux_nat) |
3107 | fprintf_unfiltered (gdb_stdlog, | |
3108 | "LLW: resume_stop SIGSTOP caught for %s.\n", | |
3109 | target_pid_to_str (lp->ptid)); | |
3110 | } | |
3111 | else | |
3112 | { | |
3113 | /* This is a delayed SIGSTOP. Filter out the event. */ | |
02f3fc28 | 3114 | |
25289eb2 PA |
3115 | if (debug_linux_nat) |
3116 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 3117 | "LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n", |
25289eb2 PA |
3118 | lp->step ? |
3119 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3120 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3121 | |
2bf6fb9d | 3122 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
25289eb2 | 3123 | gdb_assert (lp->resumed); |
25289eb2 PA |
3124 | return NULL; |
3125 | } | |
02f3fc28 PA |
3126 | } |
3127 | ||
57380f4e DJ |
3128 | /* Make sure we don't report a SIGINT that we have already displayed |
3129 | for another thread. */ | |
3130 | if (lp->ignore_sigint | |
3131 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3132 | { | |
3133 | if (debug_linux_nat) | |
3134 | fprintf_unfiltered (gdb_stdlog, | |
3135 | "LLW: Delayed SIGINT caught for %s.\n", | |
3136 | target_pid_to_str (lp->ptid)); | |
3137 | ||
3138 | /* This is a delayed SIGINT. */ | |
3139 | lp->ignore_sigint = 0; | |
3140 | ||
8a99810d | 3141 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3142 | if (debug_linux_nat) |
3143 | fprintf_unfiltered (gdb_stdlog, | |
3144 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3145 | lp->step ? | |
3146 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3147 | target_pid_to_str (lp->ptid)); | |
57380f4e DJ |
3148 | gdb_assert (lp->resumed); |
3149 | ||
3150 | /* Discard the event. */ | |
3151 | return NULL; | |
3152 | } | |
3153 | ||
9c02b525 PA |
3154 | /* Don't report signals that GDB isn't interested in, such as |
3155 | signals that are neither printed nor stopped upon. Stopping all | |
3156 | threads can be a bit time-consuming so if we want decent | |
3157 | performance with heavily multi-threaded programs, especially when | |
3158 | they're using a high frequency timer, we'd better avoid it if we | |
3159 | can. */ | |
3160 | if (WIFSTOPPED (status)) | |
3161 | { | |
3162 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); | |
3163 | ||
fbea99ea | 3164 | if (!target_is_non_stop_p ()) |
9c02b525 PA |
3165 | { |
3166 | /* Only do the below in all-stop, as we currently use SIGSTOP | |
3167 | to implement target_stop (see linux_nat_stop) in | |
3168 | non-stop. */ | |
3169 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) | |
3170 | { | |
3171 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3172 | forwarded to the entire process group, that is, all LWPs | |
3173 | will receive it - unless they're using CLONE_THREAD to | |
3174 | share signals. Since we only want to report it once, we | |
3175 | mark it as ignored for all LWPs except this one. */ | |
3176 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3177 | set_ignore_sigint, NULL); | |
3178 | lp->ignore_sigint = 0; | |
3179 | } | |
3180 | else | |
3181 | maybe_clear_ignore_sigint (lp); | |
3182 | } | |
3183 | ||
3184 | /* When using hardware single-step, we need to report every signal. | |
c9587f88 AT |
3185 | Otherwise, signals in pass_mask may be short-circuited |
3186 | except signals that might be caused by a breakpoint. */ | |
9c02b525 | 3187 | if (!lp->step |
c9587f88 AT |
3188 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)) |
3189 | && !linux_wstatus_maybe_breakpoint (status)) | |
9c02b525 PA |
3190 | { |
3191 | linux_resume_one_lwp (lp, lp->step, signo); | |
3192 | if (debug_linux_nat) | |
3193 | fprintf_unfiltered (gdb_stdlog, | |
3194 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3195 | lp->step ? | |
3196 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3197 | target_pid_to_str (lp->ptid), | |
3198 | (signo != GDB_SIGNAL_0 | |
3199 | ? strsignal (gdb_signal_to_host (signo)) | |
3200 | : "0")); | |
3201 | return NULL; | |
3202 | } | |
3203 | } | |
3204 | ||
02f3fc28 PA |
3205 | /* An interesting event. */ |
3206 | gdb_assert (lp); | |
ca2163eb | 3207 | lp->status = status; |
9c02b525 | 3208 | save_sigtrap (lp); |
02f3fc28 PA |
3209 | return lp; |
3210 | } | |
3211 | ||
0e5bf2a8 PA |
3212 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3213 | their exits until all other threads in the group have exited. */ | |
3214 | ||
3215 | static void | |
3216 | check_zombie_leaders (void) | |
3217 | { | |
3218 | struct inferior *inf; | |
3219 | ||
3220 | ALL_INFERIORS (inf) | |
3221 | { | |
3222 | struct lwp_info *leader_lp; | |
3223 | ||
3224 | if (inf->pid == 0) | |
3225 | continue; | |
3226 | ||
3227 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3228 | if (leader_lp != NULL | |
3229 | /* Check if there are other threads in the group, as we may | |
3230 | have raced with the inferior simply exiting. */ | |
3231 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3232 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3233 | { |
3234 | if (debug_linux_nat) | |
3235 | fprintf_unfiltered (gdb_stdlog, | |
3236 | "CZL: Thread group leader %d zombie " | |
3237 | "(it exited, or another thread execd).\n", | |
3238 | inf->pid); | |
3239 | ||
3240 | /* A leader zombie can mean one of two things: | |
3241 | ||
3242 | - It exited, and there's an exit status pending | |
3243 | available, or only the leader exited (not the whole | |
3244 | program). In the latter case, we can't waitpid the | |
3245 | leader's exit status until all other threads are gone. | |
3246 | ||
3247 | - There are 3 or more threads in the group, and a thread | |
3248 | other than the leader exec'd. On an exec, the Linux | |
3249 | kernel destroys all other threads (except the execing | |
3250 | one) in the thread group, and resets the execing thread's | |
3251 | tid to the tgid. No exit notification is sent for the | |
3252 | execing thread -- from the ptracer's perspective, it | |
3253 | appears as though the execing thread just vanishes. | |
3254 | Until we reap all other threads except the leader and the | |
3255 | execing thread, the leader will be zombie, and the | |
3256 | execing thread will be in `D (disc sleep)'. As soon as | |
3257 | all other threads are reaped, the execing thread changes | |
3258 | it's tid to the tgid, and the previous (zombie) leader | |
3259 | vanishes, giving place to the "new" leader. We could try | |
3260 | distinguishing the exit and exec cases, by waiting once | |
3261 | more, and seeing if something comes out, but it doesn't | |
3262 | sound useful. The previous leader _does_ go away, and | |
3263 | we'll re-add the new one once we see the exec event | |
3264 | (which is just the same as what would happen if the | |
3265 | previous leader did exit voluntarily before some other | |
3266 | thread execs). */ | |
3267 | ||
3268 | if (debug_linux_nat) | |
3269 | fprintf_unfiltered (gdb_stdlog, | |
3270 | "CZL: Thread group leader %d vanished.\n", | |
3271 | inf->pid); | |
3272 | exit_lwp (leader_lp); | |
3273 | } | |
3274 | } | |
3275 | } | |
3276 | ||
d6b0e80f | 3277 | static ptid_t |
7feb7d06 | 3278 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3279 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3280 | int target_options) | |
d6b0e80f | 3281 | { |
fc9b8e47 | 3282 | sigset_t prev_mask; |
4b60df3d | 3283 | enum resume_kind last_resume_kind; |
12d9289a | 3284 | struct lwp_info *lp; |
12d9289a | 3285 | int status; |
d6b0e80f | 3286 | |
01124a23 | 3287 | if (debug_linux_nat) |
b84876c2 PA |
3288 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3289 | ||
f973ed9c DJ |
3290 | /* The first time we get here after starting a new inferior, we may |
3291 | not have added it to the LWP list yet - this is the earliest | |
3292 | moment at which we know its PID. */ | |
d90e17a7 | 3293 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3294 | { |
27c9d204 PA |
3295 | /* Upgrade the main thread's ptid. */ |
3296 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3297 | ptid_build (ptid_get_pid (inferior_ptid), |
3298 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3299 | |
26cb8b7c | 3300 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3301 | lp->resumed = 1; |
3302 | } | |
3303 | ||
12696c10 | 3304 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3305 | block_child_signals (&prev_mask); |
d6b0e80f | 3306 | |
d6b0e80f | 3307 | /* First check if there is a LWP with a wait status pending. */ |
8a99810d PA |
3308 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3309 | if (lp != NULL) | |
d6b0e80f AC |
3310 | { |
3311 | if (debug_linux_nat) | |
d6b0e80f AC |
3312 | fprintf_unfiltered (gdb_stdlog, |
3313 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3314 | status_to_str (lp->status), |
d6b0e80f | 3315 | target_pid_to_str (lp->ptid)); |
d6b0e80f AC |
3316 | } |
3317 | ||
9c02b525 PA |
3318 | /* But if we don't find a pending event, we'll have to wait. Always |
3319 | pull all events out of the kernel. We'll randomly select an | |
3320 | event LWP out of all that have events, to prevent starvation. */ | |
7feb7d06 | 3321 | |
d90e17a7 | 3322 | while (lp == NULL) |
d6b0e80f AC |
3323 | { |
3324 | pid_t lwpid; | |
3325 | ||
0e5bf2a8 PA |
3326 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3327 | quirks: | |
3328 | ||
3329 | - If the thread group leader exits while other threads in the | |
3330 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3331 | waitpid won't return an exit status until the other threads | |
3332 | in the group are reapped. | |
3333 | ||
3334 | - When a non-leader thread execs, that thread just vanishes | |
3335 | without reporting an exit (so we'd hang if we waited for it | |
3336 | explicitly in that case). The exec event is reported to | |
3337 | the TGID pid. */ | |
3338 | ||
3339 | errno = 0; | |
3340 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3341 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3342 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3343 | ||
3344 | if (debug_linux_nat) | |
3345 | fprintf_unfiltered (gdb_stdlog, | |
3346 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3347 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3348 | |
d6b0e80f AC |
3349 | if (lwpid > 0) |
3350 | { | |
d6b0e80f AC |
3351 | if (debug_linux_nat) |
3352 | { | |
3353 | fprintf_unfiltered (gdb_stdlog, | |
3354 | "LLW: waitpid %ld received %s\n", | |
3355 | (long) lwpid, status_to_str (status)); | |
3356 | } | |
3357 | ||
9c02b525 | 3358 | linux_nat_filter_event (lwpid, status); |
0e5bf2a8 PA |
3359 | /* Retry until nothing comes out of waitpid. A single |
3360 | SIGCHLD can indicate more than one child stopped. */ | |
3361 | continue; | |
d6b0e80f AC |
3362 | } |
3363 | ||
20ba1ce6 PA |
3364 | /* Now that we've pulled all events out of the kernel, resume |
3365 | LWPs that don't have an interesting event to report. */ | |
3366 | iterate_over_lwps (minus_one_ptid, | |
3367 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
3368 | ||
3369 | /* ... and find an LWP with a status to report to the core, if | |
3370 | any. */ | |
9c02b525 PA |
3371 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3372 | if (lp != NULL) | |
3373 | break; | |
3374 | ||
0e5bf2a8 PA |
3375 | /* Check for zombie thread group leaders. Those can't be reaped |
3376 | until all other threads in the thread group are. */ | |
3377 | check_zombie_leaders (); | |
d6b0e80f | 3378 | |
0e5bf2a8 PA |
3379 | /* If there are no resumed children left, bail. We'd be stuck |
3380 | forever in the sigsuspend call below otherwise. */ | |
3381 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3382 | { | |
3383 | if (debug_linux_nat) | |
3384 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3385 | |
0e5bf2a8 | 3386 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3387 | |
0e5bf2a8 PA |
3388 | restore_child_signals_mask (&prev_mask); |
3389 | return minus_one_ptid; | |
d6b0e80f | 3390 | } |
28736962 | 3391 | |
0e5bf2a8 PA |
3392 | /* No interesting event to report to the core. */ |
3393 | ||
3394 | if (target_options & TARGET_WNOHANG) | |
3395 | { | |
01124a23 | 3396 | if (debug_linux_nat) |
28736962 PA |
3397 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3398 | ||
0e5bf2a8 | 3399 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3400 | restore_child_signals_mask (&prev_mask); |
3401 | return minus_one_ptid; | |
3402 | } | |
d6b0e80f AC |
3403 | |
3404 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3405 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3406 | |
3407 | /* Block until we get an event reported with SIGCHLD. */ | |
d36bf488 DE |
3408 | if (debug_linux_nat) |
3409 | fprintf_unfiltered (gdb_stdlog, "LNW: about to sigsuspend\n"); | |
0e5bf2a8 | 3410 | sigsuspend (&suspend_mask); |
d6b0e80f AC |
3411 | } |
3412 | ||
d6b0e80f AC |
3413 | gdb_assert (lp); |
3414 | ||
ca2163eb PA |
3415 | status = lp->status; |
3416 | lp->status = 0; | |
3417 | ||
fbea99ea | 3418 | if (!target_is_non_stop_p ()) |
4c28f408 PA |
3419 | { |
3420 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3421 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3422 | |
3423 | /* ... and wait until all of them have reported back that | |
3424 | they're no longer running. */ | |
d90e17a7 | 3425 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
9c02b525 PA |
3426 | } |
3427 | ||
3428 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
3429 | among those that have had events. Giving equal priority to all | |
3430 | LWPs that have had events helps prevent starvation. */ | |
3431 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) | |
3432 | select_event_lwp (ptid, &lp, &status); | |
3433 | ||
3434 | gdb_assert (lp != NULL); | |
3435 | ||
3436 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
faf09f01 PA |
3437 | it was a software breakpoint, and we can't reliably support the |
3438 | "stopped by software breakpoint" stop reason. */ | |
3439 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3440 | && !USE_SIGTRAP_SIGINFO) | |
9c02b525 PA |
3441 | { |
3442 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
3443 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
527a273a | 3444 | int decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
4c28f408 | 3445 | |
9c02b525 PA |
3446 | if (decr_pc != 0) |
3447 | { | |
3448 | CORE_ADDR pc; | |
d6b0e80f | 3449 | |
9c02b525 PA |
3450 | pc = regcache_read_pc (regcache); |
3451 | regcache_write_pc (regcache, pc + decr_pc); | |
3452 | } | |
3453 | } | |
e3e9f5a2 | 3454 | |
9c02b525 PA |
3455 | /* We'll need this to determine whether to report a SIGSTOP as |
3456 | GDB_SIGNAL_0. Need to take a copy because resume_clear_callback | |
3457 | clears it. */ | |
3458 | last_resume_kind = lp->last_resume_kind; | |
4b60df3d | 3459 | |
fbea99ea | 3460 | if (!target_is_non_stop_p ()) |
9c02b525 | 3461 | { |
e3e9f5a2 PA |
3462 | /* In all-stop, from the core's perspective, all LWPs are now |
3463 | stopped until a new resume action is sent over. */ | |
3464 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3465 | } | |
3466 | else | |
25289eb2 | 3467 | { |
4b60df3d | 3468 | resume_clear_callback (lp, NULL); |
25289eb2 | 3469 | } |
d6b0e80f | 3470 | |
26ab7092 | 3471 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3472 | { |
d6b0e80f AC |
3473 | if (debug_linux_nat) |
3474 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3475 | "LLW: trap ptid is %s.\n", |
3476 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3477 | } |
d6b0e80f AC |
3478 | |
3479 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3480 | { | |
3481 | *ourstatus = lp->waitstatus; | |
3482 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3483 | } | |
3484 | else | |
3485 | store_waitstatus (ourstatus, status); | |
3486 | ||
01124a23 | 3487 | if (debug_linux_nat) |
b84876c2 PA |
3488 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3489 | ||
7feb7d06 | 3490 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3491 | |
4b60df3d | 3492 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3493 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3494 | && WSTOPSIG (status) == SIGSTOP) | |
3495 | { | |
3496 | /* A thread that has been requested to stop by GDB with | |
3497 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3498 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3499 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3500 | } |
3501 | ||
1e225492 JK |
3502 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3503 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3504 | lp->core = -1; | |
3505 | else | |
2e794194 | 3506 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3507 | |
f973ed9c | 3508 | return lp->ptid; |
d6b0e80f AC |
3509 | } |
3510 | ||
e3e9f5a2 PA |
3511 | /* Resume LWPs that are currently stopped without any pending status |
3512 | to report, but are resumed from the core's perspective. */ | |
3513 | ||
3514 | static int | |
3515 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3516 | { | |
9a3c8263 | 3517 | ptid_t *wait_ptid_p = (ptid_t *) data; |
e3e9f5a2 | 3518 | |
4dd63d48 PA |
3519 | if (!lp->stopped) |
3520 | { | |
3521 | if (debug_linux_nat) | |
3522 | fprintf_unfiltered (gdb_stdlog, | |
3523 | "RSRL: NOT resuming LWP %s, not stopped\n", | |
3524 | target_pid_to_str (lp->ptid)); | |
3525 | } | |
3526 | else if (!lp->resumed) | |
3527 | { | |
3528 | if (debug_linux_nat) | |
3529 | fprintf_unfiltered (gdb_stdlog, | |
3530 | "RSRL: NOT resuming LWP %s, not resumed\n", | |
3531 | target_pid_to_str (lp->ptid)); | |
3532 | } | |
3533 | else if (lwp_status_pending_p (lp)) | |
3534 | { | |
3535 | if (debug_linux_nat) | |
3536 | fprintf_unfiltered (gdb_stdlog, | |
3537 | "RSRL: NOT resuming LWP %s, has pending status\n", | |
3538 | target_pid_to_str (lp->ptid)); | |
3539 | } | |
3540 | else | |
e3e9f5a2 | 3541 | { |
336060f3 PA |
3542 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3543 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
336060f3 | 3544 | |
23f238d3 | 3545 | TRY |
e3e9f5a2 | 3546 | { |
23f238d3 PA |
3547 | CORE_ADDR pc = regcache_read_pc (regcache); |
3548 | int leave_stopped = 0; | |
e3e9f5a2 | 3549 | |
23f238d3 PA |
3550 | /* Don't bother if there's a breakpoint at PC that we'd hit |
3551 | immediately, and we're not waiting for this LWP. */ | |
3552 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3553 | { | |
3554 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) | |
3555 | leave_stopped = 1; | |
3556 | } | |
e3e9f5a2 | 3557 | |
23f238d3 PA |
3558 | if (!leave_stopped) |
3559 | { | |
3560 | if (debug_linux_nat) | |
3561 | fprintf_unfiltered (gdb_stdlog, | |
3562 | "RSRL: resuming stopped-resumed LWP %s at " | |
3563 | "%s: step=%d\n", | |
3564 | target_pid_to_str (lp->ptid), | |
3565 | paddress (gdbarch, pc), | |
3566 | lp->step); | |
3567 | ||
3568 | linux_resume_one_lwp_throw (lp, lp->step, GDB_SIGNAL_0); | |
3569 | } | |
3570 | } | |
3571 | CATCH (ex, RETURN_MASK_ERROR) | |
3572 | { | |
3573 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
3574 | throw_exception (ex); | |
3575 | } | |
3576 | END_CATCH | |
e3e9f5a2 PA |
3577 | } |
3578 | ||
3579 | return 0; | |
3580 | } | |
3581 | ||
7feb7d06 PA |
3582 | static ptid_t |
3583 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3584 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3585 | int target_options) | |
7feb7d06 PA |
3586 | { |
3587 | ptid_t event_ptid; | |
3588 | ||
3589 | if (debug_linux_nat) | |
09826ec5 PA |
3590 | { |
3591 | char *options_string; | |
3592 | ||
3593 | options_string = target_options_to_string (target_options); | |
3594 | fprintf_unfiltered (gdb_stdlog, | |
3595 | "linux_nat_wait: [%s], [%s]\n", | |
3596 | target_pid_to_str (ptid), | |
3597 | options_string); | |
3598 | xfree (options_string); | |
3599 | } | |
7feb7d06 PA |
3600 | |
3601 | /* Flush the async file first. */ | |
d9d41e78 | 3602 | if (target_is_async_p ()) |
7feb7d06 PA |
3603 | async_file_flush (); |
3604 | ||
e3e9f5a2 PA |
3605 | /* Resume LWPs that are currently stopped without any pending status |
3606 | to report, but are resumed from the core's perspective. LWPs get | |
3607 | in this state if we find them stopping at a time we're not | |
3608 | interested in reporting the event (target_wait on a | |
3609 | specific_process, for example, see linux_nat_wait_1), and | |
3610 | meanwhile the event became uninteresting. Don't bother resuming | |
3611 | LWPs we're not going to wait for if they'd stop immediately. */ | |
fbea99ea | 3612 | if (target_is_non_stop_p ()) |
e3e9f5a2 PA |
3613 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); |
3614 | ||
47608cb1 | 3615 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3616 | |
3617 | /* If we requested any event, and something came out, assume there | |
3618 | may be more. If we requested a specific lwp or process, also | |
3619 | assume there may be more. */ | |
d9d41e78 | 3620 | if (target_is_async_p () |
6953d224 PA |
3621 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3622 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3623 | || !ptid_equal (ptid, minus_one_ptid))) |
3624 | async_file_mark (); | |
3625 | ||
7feb7d06 PA |
3626 | return event_ptid; |
3627 | } | |
3628 | ||
d6b0e80f AC |
3629 | static int |
3630 | kill_callback (struct lwp_info *lp, void *data) | |
3631 | { | |
ed731959 JK |
3632 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3633 | ||
3634 | errno = 0; | |
69ff6be5 | 3635 | kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 | 3636 | if (debug_linux_nat) |
57745c90 PA |
3637 | { |
3638 | int save_errno = errno; | |
3639 | ||
3640 | fprintf_unfiltered (gdb_stdlog, | |
3641 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3642 | target_pid_to_str (lp->ptid), | |
3643 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3644 | } | |
ed731959 JK |
3645 | |
3646 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3647 | ||
d6b0e80f | 3648 | errno = 0; |
dfd4cc63 | 3649 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f | 3650 | if (debug_linux_nat) |
57745c90 PA |
3651 | { |
3652 | int save_errno = errno; | |
3653 | ||
3654 | fprintf_unfiltered (gdb_stdlog, | |
3655 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3656 | target_pid_to_str (lp->ptid), | |
3657 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3658 | } | |
d6b0e80f AC |
3659 | |
3660 | return 0; | |
3661 | } | |
3662 | ||
3663 | static int | |
3664 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3665 | { | |
3666 | pid_t pid; | |
3667 | ||
3668 | /* We must make sure that there are no pending events (delayed | |
3669 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3670 | program doesn't interfere with any following debugging session. */ | |
3671 | ||
3672 | /* For cloned processes we must check both with __WCLONE and | |
3673 | without, since the exit status of a cloned process isn't reported | |
3674 | with __WCLONE. */ | |
3675 | if (lp->cloned) | |
3676 | { | |
3677 | do | |
3678 | { | |
dfd4cc63 | 3679 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3680 | if (pid != (pid_t) -1) |
d6b0e80f | 3681 | { |
e85a822c DJ |
3682 | if (debug_linux_nat) |
3683 | fprintf_unfiltered (gdb_stdlog, | |
3684 | "KWC: wait %s received unknown.\n", | |
3685 | target_pid_to_str (lp->ptid)); | |
3686 | /* The Linux kernel sometimes fails to kill a thread | |
3687 | completely after PTRACE_KILL; that goes from the stop | |
3688 | point in do_fork out to the one in | |
3689 | get_signal_to_deliever and waits again. So kill it | |
3690 | again. */ | |
3691 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3692 | } |
3693 | } | |
dfd4cc63 | 3694 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3695 | |
3696 | gdb_assert (pid == -1 && errno == ECHILD); | |
3697 | } | |
3698 | ||
3699 | do | |
3700 | { | |
dfd4cc63 | 3701 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3702 | if (pid != (pid_t) -1) |
d6b0e80f | 3703 | { |
e85a822c DJ |
3704 | if (debug_linux_nat) |
3705 | fprintf_unfiltered (gdb_stdlog, | |
3706 | "KWC: wait %s received unk.\n", | |
3707 | target_pid_to_str (lp->ptid)); | |
3708 | /* See the call to kill_callback above. */ | |
3709 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3710 | } |
3711 | } | |
dfd4cc63 | 3712 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3713 | |
3714 | gdb_assert (pid == -1 && errno == ECHILD); | |
3715 | return 0; | |
3716 | } | |
3717 | ||
3718 | static void | |
7d85a9c0 | 3719 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3720 | { |
f973ed9c DJ |
3721 | struct target_waitstatus last; |
3722 | ptid_t last_ptid; | |
3723 | int status; | |
d6b0e80f | 3724 | |
f973ed9c DJ |
3725 | /* If we're stopped while forking and we haven't followed yet, |
3726 | kill the other task. We need to do this first because the | |
3727 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3728 | |
f973ed9c | 3729 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3730 | |
f973ed9c DJ |
3731 | if (last.kind == TARGET_WAITKIND_FORKED |
3732 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3733 | { | |
dfd4cc63 | 3734 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3735 | wait (&status); |
26cb8b7c PA |
3736 | |
3737 | /* Let the arch-specific native code know this process is | |
3738 | gone. */ | |
dfd4cc63 | 3739 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3740 | } |
3741 | ||
3742 | if (forks_exist_p ()) | |
7feb7d06 | 3743 | linux_fork_killall (); |
f973ed9c DJ |
3744 | else |
3745 | { | |
d90e17a7 | 3746 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3747 | |
4c28f408 PA |
3748 | /* Stop all threads before killing them, since ptrace requires |
3749 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3750 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3751 | /* ... and wait until all of them have reported back that |
3752 | they're no longer running. */ | |
d90e17a7 | 3753 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3754 | |
f973ed9c | 3755 | /* Kill all LWP's ... */ |
d90e17a7 | 3756 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3757 | |
3758 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3759 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3760 | } |
3761 | ||
3762 | target_mourn_inferior (); | |
d6b0e80f AC |
3763 | } |
3764 | ||
3765 | static void | |
136d6dae | 3766 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3767 | { |
26cb8b7c PA |
3768 | int pid = ptid_get_pid (inferior_ptid); |
3769 | ||
3770 | purge_lwp_list (pid); | |
d6b0e80f | 3771 | |
f973ed9c | 3772 | if (! forks_exist_p ()) |
d90e17a7 PA |
3773 | /* Normal case, no other forks available. */ |
3774 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3775 | else |
3776 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3777 | there are other viable forks to debug. Delete the exiting | |
3778 | one and context-switch to the first available. */ | |
3779 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3780 | |
3781 | /* Let the arch-specific native code know this process is gone. */ | |
3782 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3783 | } |
3784 | ||
5b009018 PA |
3785 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3786 | layout of the inferiors' architecture. */ | |
3787 | ||
3788 | static void | |
a5362b9a | 3789 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3790 | { |
3791 | int done = 0; | |
3792 | ||
3793 | if (linux_nat_siginfo_fixup != NULL) | |
3794 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3795 | ||
3796 | /* If there was no callback, or the callback didn't do anything, | |
3797 | then just do a straight memcpy. */ | |
3798 | if (!done) | |
3799 | { | |
3800 | if (direction == 1) | |
a5362b9a | 3801 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3802 | else |
a5362b9a | 3803 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3804 | } |
3805 | } | |
3806 | ||
9b409511 | 3807 | static enum target_xfer_status |
4aa995e1 PA |
3808 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3809 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3810 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3811 | ULONGEST *xfered_len) | |
4aa995e1 | 3812 | { |
4aa995e1 | 3813 | int pid; |
a5362b9a TS |
3814 | siginfo_t siginfo; |
3815 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3816 | |
3817 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3818 | gdb_assert (readbuf || writebuf); | |
3819 | ||
dfd4cc63 | 3820 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3821 | if (pid == 0) |
dfd4cc63 | 3822 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3823 | |
3824 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3825 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3826 | |
3827 | errno = 0; | |
3828 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3829 | if (errno != 0) | |
2ed4b548 | 3830 | return TARGET_XFER_E_IO; |
4aa995e1 | 3831 | |
5b009018 PA |
3832 | /* When GDB is built as a 64-bit application, ptrace writes into |
3833 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3834 | inferior with a 64-bit GDB should look the same as debugging it | |
3835 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3836 | the converted layout, so any read/write will have to be done | |
3837 | post-conversion. */ | |
3838 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3839 | ||
4aa995e1 PA |
3840 | if (offset + len > sizeof (siginfo)) |
3841 | len = sizeof (siginfo) - offset; | |
3842 | ||
3843 | if (readbuf != NULL) | |
5b009018 | 3844 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3845 | else |
3846 | { | |
5b009018 PA |
3847 | memcpy (inf_siginfo + offset, writebuf, len); |
3848 | ||
3849 | /* Convert back to ptrace layout before flushing it out. */ | |
3850 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3851 | ||
4aa995e1 PA |
3852 | errno = 0; |
3853 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3854 | if (errno != 0) | |
2ed4b548 | 3855 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3856 | } |
3857 | ||
9b409511 YQ |
3858 | *xfered_len = len; |
3859 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3860 | } |
3861 | ||
9b409511 | 3862 | static enum target_xfer_status |
10d6c8cd DJ |
3863 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3864 | const char *annex, gdb_byte *readbuf, | |
3865 | const gdb_byte *writebuf, | |
9b409511 | 3866 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3867 | { |
4aa995e1 | 3868 | struct cleanup *old_chain; |
9b409511 | 3869 | enum target_xfer_status xfer; |
d6b0e80f | 3870 | |
4aa995e1 PA |
3871 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3872 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3873 | offset, len, xfered_len); |
4aa995e1 | 3874 | |
c35b1492 PA |
3875 | /* The target is connected but no live inferior is selected. Pass |
3876 | this request down to a lower stratum (e.g., the executable | |
3877 | file). */ | |
3878 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 3879 | return TARGET_XFER_EOF; |
c35b1492 | 3880 | |
4aa995e1 PA |
3881 | old_chain = save_inferior_ptid (); |
3882 | ||
dfd4cc63 LM |
3883 | if (ptid_lwp_p (inferior_ptid)) |
3884 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3885 | |
10d6c8cd | 3886 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3887 | offset, len, xfered_len); |
d6b0e80f AC |
3888 | |
3889 | do_cleanups (old_chain); | |
3890 | return xfer; | |
3891 | } | |
3892 | ||
3893 | static int | |
28439f5e | 3894 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3895 | { |
8c6a60d1 | 3896 | int err, tmp_errno; |
4c28f408 | 3897 | |
dfd4cc63 | 3898 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3899 | |
4c28f408 PA |
3900 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3901 | running thread errors out claiming that the thread doesn't | |
3902 | exist. */ | |
dfd4cc63 | 3903 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3904 | tmp_errno = errno; |
d6b0e80f AC |
3905 | if (debug_linux_nat) |
3906 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3907 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3908 | target_pid_to_str (ptid), |
8c6a60d1 | 3909 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3910 | |
4c28f408 | 3911 | if (err != 0) |
d6b0e80f AC |
3912 | return 0; |
3913 | ||
3914 | return 1; | |
3915 | } | |
3916 | ||
28439f5e PA |
3917 | static int |
3918 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3919 | { | |
3920 | return linux_thread_alive (ptid); | |
3921 | } | |
3922 | ||
8a06aea7 PA |
3923 | /* Implement the to_update_thread_list target method for this |
3924 | target. */ | |
3925 | ||
3926 | static void | |
3927 | linux_nat_update_thread_list (struct target_ops *ops) | |
3928 | { | |
3929 | if (linux_supports_traceclone ()) | |
3930 | { | |
3931 | /* With support for clone events, we add/delete threads from the | |
3932 | list as clone/exit events are processed, so just try deleting | |
3933 | exited threads still in the thread list. */ | |
3934 | delete_exited_threads (); | |
3935 | } | |
3936 | else | |
3937 | prune_threads (); | |
3938 | } | |
3939 | ||
d6b0e80f | 3940 | static char * |
117de6a9 | 3941 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3942 | { |
3943 | static char buf[64]; | |
3944 | ||
dfd4cc63 LM |
3945 | if (ptid_lwp_p (ptid) |
3946 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
3947 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 3948 | { |
dfd4cc63 | 3949 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
3950 | return buf; |
3951 | } | |
3952 | ||
3953 | return normal_pid_to_str (ptid); | |
3954 | } | |
3955 | ||
73ede765 | 3956 | static const char * |
503a628d | 3957 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 | 3958 | { |
79efa585 | 3959 | return linux_proc_tid_get_name (thr->ptid); |
4694da01 TT |
3960 | } |
3961 | ||
dba24537 AC |
3962 | /* Accepts an integer PID; Returns a string representing a file that |
3963 | can be opened to get the symbols for the child process. */ | |
3964 | ||
6d8fd2b7 | 3965 | static char * |
8dd27370 | 3966 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 3967 | { |
e0d86d2c | 3968 | return linux_proc_pid_to_exec_file (pid); |
dba24537 AC |
3969 | } |
3970 | ||
10d6c8cd DJ |
3971 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
3972 | filesystem. Because we can use a single read() call for /proc, this | |
3973 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
3974 | but it doesn't support writes. */ | |
3975 | ||
9b409511 | 3976 | static enum target_xfer_status |
10d6c8cd DJ |
3977 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
3978 | const char *annex, gdb_byte *readbuf, | |
3979 | const gdb_byte *writebuf, | |
9b409511 | 3980 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 3981 | { |
10d6c8cd DJ |
3982 | LONGEST ret; |
3983 | int fd; | |
dba24537 AC |
3984 | char filename[64]; |
3985 | ||
10d6c8cd | 3986 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
f486487f | 3987 | return TARGET_XFER_EOF; |
dba24537 AC |
3988 | |
3989 | /* Don't bother for one word. */ | |
3990 | if (len < 3 * sizeof (long)) | |
9b409511 | 3991 | return TARGET_XFER_EOF; |
dba24537 AC |
3992 | |
3993 | /* We could keep this file open and cache it - possibly one per | |
3994 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
3995 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
3996 | ptid_get_pid (inferior_ptid)); | |
614c279d | 3997 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 3998 | if (fd == -1) |
9b409511 | 3999 | return TARGET_XFER_EOF; |
dba24537 AC |
4000 | |
4001 | /* If pread64 is available, use it. It's faster if the kernel | |
4002 | supports it (only one syscall), and it's 64-bit safe even on | |
4003 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4004 | application). */ | |
4005 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4006 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4007 | #else |
10d6c8cd | 4008 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4009 | #endif |
4010 | ret = 0; | |
4011 | else | |
4012 | ret = len; | |
4013 | ||
4014 | close (fd); | |
9b409511 YQ |
4015 | |
4016 | if (ret == 0) | |
4017 | return TARGET_XFER_EOF; | |
4018 | else | |
4019 | { | |
4020 | *xfered_len = ret; | |
4021 | return TARGET_XFER_OK; | |
4022 | } | |
dba24537 AC |
4023 | } |
4024 | ||
efcbbd14 UW |
4025 | |
4026 | /* Enumerate spufs IDs for process PID. */ | |
4027 | static LONGEST | |
b55e14c7 | 4028 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4029 | { |
f5656ead | 4030 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4031 | LONGEST pos = 0; |
4032 | LONGEST written = 0; | |
4033 | char path[128]; | |
4034 | DIR *dir; | |
4035 | struct dirent *entry; | |
4036 | ||
4037 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4038 | dir = opendir (path); | |
4039 | if (!dir) | |
4040 | return -1; | |
4041 | ||
4042 | rewinddir (dir); | |
4043 | while ((entry = readdir (dir)) != NULL) | |
4044 | { | |
4045 | struct stat st; | |
4046 | struct statfs stfs; | |
4047 | int fd; | |
4048 | ||
4049 | fd = atoi (entry->d_name); | |
4050 | if (!fd) | |
4051 | continue; | |
4052 | ||
4053 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4054 | if (stat (path, &st) != 0) | |
4055 | continue; | |
4056 | if (!S_ISDIR (st.st_mode)) | |
4057 | continue; | |
4058 | ||
4059 | if (statfs (path, &stfs) != 0) | |
4060 | continue; | |
4061 | if (stfs.f_type != SPUFS_MAGIC) | |
4062 | continue; | |
4063 | ||
4064 | if (pos >= offset && pos + 4 <= offset + len) | |
4065 | { | |
4066 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4067 | written += 4; | |
4068 | } | |
4069 | pos += 4; | |
4070 | } | |
4071 | ||
4072 | closedir (dir); | |
4073 | return written; | |
4074 | } | |
4075 | ||
4076 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4077 | object type, using the /proc file system. */ | |
9b409511 YQ |
4078 | |
4079 | static enum target_xfer_status | |
efcbbd14 UW |
4080 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4081 | const char *annex, gdb_byte *readbuf, | |
4082 | const gdb_byte *writebuf, | |
9b409511 | 4083 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4084 | { |
4085 | char buf[128]; | |
4086 | int fd = 0; | |
4087 | int ret = -1; | |
dfd4cc63 | 4088 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4089 | |
4090 | if (!annex) | |
4091 | { | |
4092 | if (!readbuf) | |
2ed4b548 | 4093 | return TARGET_XFER_E_IO; |
efcbbd14 | 4094 | else |
9b409511 YQ |
4095 | { |
4096 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4097 | ||
4098 | if (l < 0) | |
4099 | return TARGET_XFER_E_IO; | |
4100 | else if (l == 0) | |
4101 | return TARGET_XFER_EOF; | |
4102 | else | |
4103 | { | |
4104 | *xfered_len = (ULONGEST) l; | |
4105 | return TARGET_XFER_OK; | |
4106 | } | |
4107 | } | |
efcbbd14 UW |
4108 | } |
4109 | ||
4110 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4111 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4112 | if (fd <= 0) |
2ed4b548 | 4113 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4114 | |
4115 | if (offset != 0 | |
4116 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4117 | { | |
4118 | close (fd); | |
9b409511 | 4119 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4120 | } |
4121 | ||
4122 | if (writebuf) | |
4123 | ret = write (fd, writebuf, (size_t) len); | |
4124 | else if (readbuf) | |
4125 | ret = read (fd, readbuf, (size_t) len); | |
4126 | ||
4127 | close (fd); | |
9b409511 YQ |
4128 | |
4129 | if (ret < 0) | |
4130 | return TARGET_XFER_E_IO; | |
4131 | else if (ret == 0) | |
4132 | return TARGET_XFER_EOF; | |
4133 | else | |
4134 | { | |
4135 | *xfered_len = (ULONGEST) ret; | |
4136 | return TARGET_XFER_OK; | |
4137 | } | |
efcbbd14 UW |
4138 | } |
4139 | ||
4140 | ||
dba24537 AC |
4141 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4142 | ||
4143 | static void | |
4144 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4145 | { | |
4146 | int len = strlen (line) - 1; | |
4147 | const char *p; | |
4148 | int signum; | |
4149 | ||
4150 | if (line[len] != '\n') | |
8a3fe4f8 | 4151 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4152 | |
4153 | p = line; | |
4154 | signum = len * 4; | |
4155 | while (len-- > 0) | |
4156 | { | |
4157 | int digit; | |
4158 | ||
4159 | if (*p >= '0' && *p <= '9') | |
4160 | digit = *p - '0'; | |
4161 | else if (*p >= 'a' && *p <= 'f') | |
4162 | digit = *p - 'a' + 10; | |
4163 | else | |
8a3fe4f8 | 4164 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4165 | |
4166 | signum -= 4; | |
4167 | ||
4168 | if (digit & 1) | |
4169 | sigaddset (sigs, signum + 1); | |
4170 | if (digit & 2) | |
4171 | sigaddset (sigs, signum + 2); | |
4172 | if (digit & 4) | |
4173 | sigaddset (sigs, signum + 3); | |
4174 | if (digit & 8) | |
4175 | sigaddset (sigs, signum + 4); | |
4176 | ||
4177 | p++; | |
4178 | } | |
4179 | } | |
4180 | ||
4181 | /* Find process PID's pending signals from /proc/pid/status and set | |
4182 | SIGS to match. */ | |
4183 | ||
4184 | void | |
3e43a32a MS |
4185 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4186 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4187 | { |
4188 | FILE *procfile; | |
d8d2a3ee | 4189 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4190 | struct cleanup *cleanup; |
dba24537 AC |
4191 | |
4192 | sigemptyset (pending); | |
4193 | sigemptyset (blocked); | |
4194 | sigemptyset (ignored); | |
cde33bf1 | 4195 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4196 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4197 | if (procfile == NULL) |
8a3fe4f8 | 4198 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4199 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4200 | |
d8d2a3ee | 4201 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4202 | { |
4203 | /* Normal queued signals are on the SigPnd line in the status | |
4204 | file. However, 2.6 kernels also have a "shared" pending | |
4205 | queue for delivering signals to a thread group, so check for | |
4206 | a ShdPnd line also. | |
4207 | ||
4208 | Unfortunately some Red Hat kernels include the shared pending | |
4209 | queue but not the ShdPnd status field. */ | |
4210 | ||
61012eef | 4211 | if (startswith (buffer, "SigPnd:\t")) |
dba24537 | 4212 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4213 | else if (startswith (buffer, "ShdPnd:\t")) |
dba24537 | 4214 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4215 | else if (startswith (buffer, "SigBlk:\t")) |
dba24537 | 4216 | add_line_to_sigset (buffer + 8, blocked); |
61012eef | 4217 | else if (startswith (buffer, "SigIgn:\t")) |
dba24537 AC |
4218 | add_line_to_sigset (buffer + 8, ignored); |
4219 | } | |
4220 | ||
7c8a8b04 | 4221 | do_cleanups (cleanup); |
dba24537 AC |
4222 | } |
4223 | ||
9b409511 | 4224 | static enum target_xfer_status |
07e059b5 | 4225 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4226 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4227 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4228 | ULONGEST *xfered_len) | |
07e059b5 | 4229 | { |
07e059b5 VP |
4230 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4231 | ||
9b409511 YQ |
4232 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4233 | if (*xfered_len == 0) | |
4234 | return TARGET_XFER_EOF; | |
4235 | else | |
4236 | return TARGET_XFER_OK; | |
07e059b5 VP |
4237 | } |
4238 | ||
9b409511 | 4239 | static enum target_xfer_status |
10d6c8cd DJ |
4240 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4241 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4242 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4243 | ULONGEST *xfered_len) | |
10d6c8cd | 4244 | { |
9b409511 | 4245 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4246 | |
4247 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4248 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4249 | offset, len, xfered_len); |
10d6c8cd | 4250 | |
07e059b5 VP |
4251 | if (object == TARGET_OBJECT_OSDATA) |
4252 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4253 | offset, len, xfered_len); |
07e059b5 | 4254 | |
efcbbd14 UW |
4255 | if (object == TARGET_OBJECT_SPU) |
4256 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4257 | offset, len, xfered_len); |
efcbbd14 | 4258 | |
8f313923 JK |
4259 | /* GDB calculates all the addresses in possibly larget width of the address. |
4260 | Address width needs to be masked before its final use - either by | |
4261 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4262 | ||
4263 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4264 | ||
4265 | if (object == TARGET_OBJECT_MEMORY) | |
4266 | { | |
f5656ead | 4267 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4268 | |
4269 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4270 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4271 | } | |
4272 | ||
10d6c8cd | 4273 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4274 | offset, len, xfered_len); |
4275 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4276 | return xfer; |
4277 | ||
4278 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4279 | offset, len, xfered_len); |
10d6c8cd DJ |
4280 | } |
4281 | ||
5808517f YQ |
4282 | static void |
4283 | cleanup_target_stop (void *arg) | |
4284 | { | |
4285 | ptid_t *ptid = (ptid_t *) arg; | |
4286 | ||
4287 | gdb_assert (arg != NULL); | |
4288 | ||
4289 | /* Unpause all */ | |
a493e3e2 | 4290 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4291 | } |
4292 | ||
4293 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4294 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4295 | const char *strid) | |
5808517f YQ |
4296 | { |
4297 | char s[IPA_CMD_BUF_SIZE]; | |
4298 | struct cleanup *old_chain; | |
4299 | int pid = ptid_get_pid (inferior_ptid); | |
4300 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4301 | struct static_tracepoint_marker *marker = NULL; | |
4302 | char *p = s; | |
4303 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4304 | ||
4305 | /* Pause all */ | |
4306 | target_stop (ptid); | |
4307 | ||
4308 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4309 | s[sizeof ("qTfSTM")] = 0; | |
4310 | ||
42476b70 | 4311 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4312 | |
4313 | old_chain = make_cleanup (free_current_marker, &marker); | |
4314 | make_cleanup (cleanup_target_stop, &ptid); | |
4315 | ||
4316 | while (*p++ == 'm') | |
4317 | { | |
4318 | if (marker == NULL) | |
4319 | marker = XCNEW (struct static_tracepoint_marker); | |
4320 | ||
4321 | do | |
4322 | { | |
4323 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4324 | ||
4325 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4326 | { | |
4327 | VEC_safe_push (static_tracepoint_marker_p, | |
4328 | markers, marker); | |
4329 | marker = NULL; | |
4330 | } | |
4331 | else | |
4332 | { | |
4333 | release_static_tracepoint_marker (marker); | |
4334 | memset (marker, 0, sizeof (*marker)); | |
4335 | } | |
4336 | } | |
4337 | while (*p++ == ','); /* comma-separated list */ | |
4338 | ||
4339 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4340 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4341 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4342 | p = s; |
4343 | } | |
4344 | ||
4345 | do_cleanups (old_chain); | |
4346 | ||
4347 | return markers; | |
4348 | } | |
4349 | ||
e9efe249 | 4350 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4351 | it with local methods. */ |
4352 | ||
910122bf UW |
4353 | static void |
4354 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4355 | { |
6d8fd2b7 | 4356 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4357 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4358 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4359 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4360 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4361 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4362 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4363 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4364 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4365 | t->to_post_attach = linux_child_post_attach; |
4366 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4367 | |
4368 | super_xfer_partial = t->to_xfer_partial; | |
4369 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4370 | |
4371 | t->to_static_tracepoint_markers_by_strid | |
4372 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4373 | } |
4374 | ||
4375 | struct target_ops * | |
4376 | linux_target (void) | |
4377 | { | |
4378 | struct target_ops *t; | |
4379 | ||
4380 | t = inf_ptrace_target (); | |
4381 | linux_target_install_ops (t); | |
4382 | ||
4383 | return t; | |
4384 | } | |
4385 | ||
4386 | struct target_ops * | |
7714d83a | 4387 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4388 | { |
4389 | struct target_ops *t; | |
4390 | ||
4391 | t = inf_ptrace_trad_target (register_u_offset); | |
4392 | linux_target_install_ops (t); | |
10d6c8cd | 4393 | |
10d6c8cd DJ |
4394 | return t; |
4395 | } | |
4396 | ||
b84876c2 PA |
4397 | /* target_is_async_p implementation. */ |
4398 | ||
4399 | static int | |
6a109b6b | 4400 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 | 4401 | { |
198297aa | 4402 | return linux_is_async_p (); |
b84876c2 PA |
4403 | } |
4404 | ||
4405 | /* target_can_async_p implementation. */ | |
4406 | ||
4407 | static int | |
6a109b6b | 4408 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4409 | { |
4410 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4411 | it explicitly with the "set target-async" command. |
b84876c2 | 4412 | Someday, linux will always be async. */ |
3dd5b83d | 4413 | return target_async_permitted; |
b84876c2 PA |
4414 | } |
4415 | ||
9908b566 | 4416 | static int |
2a9a2795 | 4417 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4418 | { |
4419 | return 1; | |
4420 | } | |
4421 | ||
fbea99ea PA |
4422 | /* to_always_non_stop_p implementation. */ |
4423 | ||
4424 | static int | |
4425 | linux_nat_always_non_stop_p (struct target_ops *self) | |
4426 | { | |
f12899e9 | 4427 | return 1; |
fbea99ea PA |
4428 | } |
4429 | ||
d90e17a7 PA |
4430 | /* True if we want to support multi-process. To be removed when GDB |
4431 | supports multi-exec. */ | |
4432 | ||
2277426b | 4433 | int linux_multi_process = 1; |
d90e17a7 PA |
4434 | |
4435 | static int | |
86ce2668 | 4436 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4437 | { |
4438 | return linux_multi_process; | |
4439 | } | |
4440 | ||
03583c20 | 4441 | static int |
2bfc0540 | 4442 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4443 | { |
4444 | #ifdef HAVE_PERSONALITY | |
4445 | return 1; | |
4446 | #else | |
4447 | return 0; | |
4448 | #endif | |
4449 | } | |
4450 | ||
b84876c2 PA |
4451 | static int async_terminal_is_ours = 1; |
4452 | ||
4d4ca2a1 DE |
4453 | /* target_terminal_inferior implementation. |
4454 | ||
4455 | This is a wrapper around child_terminal_inferior to add async support. */ | |
b84876c2 PA |
4456 | |
4457 | static void | |
d2f640d4 | 4458 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 | 4459 | { |
d6b64346 | 4460 | child_terminal_inferior (self); |
b84876c2 | 4461 | |
d9d2d8b6 | 4462 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4463 | if (!async_terminal_is_ours) |
4464 | return; | |
4465 | ||
4466 | delete_file_handler (input_fd); | |
4467 | async_terminal_is_ours = 0; | |
4468 | set_sigint_trap (); | |
4469 | } | |
4470 | ||
4d4ca2a1 DE |
4471 | /* target_terminal_ours implementation. |
4472 | ||
4473 | This is a wrapper around child_terminal_ours to add async support (and | |
4474 | implement the target_terminal_ours vs target_terminal_ours_for_output | |
4475 | distinction). child_terminal_ours is currently no different than | |
4476 | child_terminal_ours_for_output. | |
4477 | We leave target_terminal_ours_for_output alone, leaving it to | |
4478 | child_terminal_ours_for_output. */ | |
b84876c2 | 4479 | |
2c0b251b | 4480 | static void |
e3594fd1 | 4481 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 | 4482 | { |
b84876c2 PA |
4483 | /* GDB should never give the terminal to the inferior if the |
4484 | inferior is running in the background (run&, continue&, etc.), | |
4485 | but claiming it sure should. */ | |
d6b64346 | 4486 | child_terminal_ours (self); |
b84876c2 | 4487 | |
b84876c2 PA |
4488 | if (async_terminal_is_ours) |
4489 | return; | |
4490 | ||
4491 | clear_sigint_trap (); | |
4492 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4493 | async_terminal_is_ours = 1; | |
4494 | } | |
4495 | ||
7feb7d06 PA |
4496 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4497 | so we notice when any child changes state, and notify the | |
4498 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4499 | above to wait for the arrival of a SIGCHLD. */ | |
4500 | ||
b84876c2 | 4501 | static void |
7feb7d06 | 4502 | sigchld_handler (int signo) |
b84876c2 | 4503 | { |
7feb7d06 PA |
4504 | int old_errno = errno; |
4505 | ||
01124a23 DE |
4506 | if (debug_linux_nat) |
4507 | ui_file_write_async_safe (gdb_stdlog, | |
4508 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4509 | |
4510 | if (signo == SIGCHLD | |
4511 | && linux_nat_event_pipe[0] != -1) | |
4512 | async_file_mark (); /* Let the event loop know that there are | |
4513 | events to handle. */ | |
4514 | ||
4515 | errno = old_errno; | |
4516 | } | |
4517 | ||
4518 | /* Callback registered with the target events file descriptor. */ | |
4519 | ||
4520 | static void | |
4521 | handle_target_event (int error, gdb_client_data client_data) | |
4522 | { | |
6a3753b3 | 4523 | inferior_event_handler (INF_REG_EVENT, NULL); |
7feb7d06 PA |
4524 | } |
4525 | ||
4526 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4527 | ||
4528 | static int | |
4529 | linux_async_pipe (int enable) | |
4530 | { | |
198297aa | 4531 | int previous = linux_is_async_p (); |
7feb7d06 PA |
4532 | |
4533 | if (previous != enable) | |
4534 | { | |
4535 | sigset_t prev_mask; | |
4536 | ||
12696c10 PA |
4537 | /* Block child signals while we create/destroy the pipe, as |
4538 | their handler writes to it. */ | |
7feb7d06 PA |
4539 | block_child_signals (&prev_mask); |
4540 | ||
4541 | if (enable) | |
4542 | { | |
614c279d | 4543 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4544 | internal_error (__FILE__, __LINE__, |
4545 | "creating event pipe failed."); | |
4546 | ||
4547 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4548 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4549 | } | |
4550 | else | |
4551 | { | |
4552 | close (linux_nat_event_pipe[0]); | |
4553 | close (linux_nat_event_pipe[1]); | |
4554 | linux_nat_event_pipe[0] = -1; | |
4555 | linux_nat_event_pipe[1] = -1; | |
4556 | } | |
4557 | ||
4558 | restore_child_signals_mask (&prev_mask); | |
4559 | } | |
4560 | ||
4561 | return previous; | |
b84876c2 PA |
4562 | } |
4563 | ||
4564 | /* target_async implementation. */ | |
4565 | ||
4566 | static void | |
6a3753b3 | 4567 | linux_nat_async (struct target_ops *ops, int enable) |
b84876c2 | 4568 | { |
6a3753b3 | 4569 | if (enable) |
b84876c2 | 4570 | { |
7feb7d06 PA |
4571 | if (!linux_async_pipe (1)) |
4572 | { | |
4573 | add_file_handler (linux_nat_event_pipe[0], | |
4574 | handle_target_event, NULL); | |
4575 | /* There may be pending events to handle. Tell the event loop | |
4576 | to poll them. */ | |
4577 | async_file_mark (); | |
4578 | } | |
b84876c2 PA |
4579 | } |
4580 | else | |
4581 | { | |
b84876c2 | 4582 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4583 | linux_async_pipe (0); |
b84876c2 PA |
4584 | } |
4585 | return; | |
4586 | } | |
4587 | ||
a493e3e2 | 4588 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4589 | event came out. */ |
4590 | ||
4c28f408 | 4591 | static int |
252fbfc8 | 4592 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4593 | { |
d90e17a7 | 4594 | if (!lwp->stopped) |
252fbfc8 | 4595 | { |
d90e17a7 PA |
4596 | if (debug_linux_nat) |
4597 | fprintf_unfiltered (gdb_stdlog, | |
4598 | "LNSL: running -> suspending %s\n", | |
4599 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4600 | |
252fbfc8 | 4601 | |
25289eb2 PA |
4602 | if (lwp->last_resume_kind == resume_stop) |
4603 | { | |
4604 | if (debug_linux_nat) | |
4605 | fprintf_unfiltered (gdb_stdlog, | |
4606 | "linux-nat: already stopping LWP %ld at " | |
4607 | "GDB's request\n", | |
4608 | ptid_get_lwp (lwp->ptid)); | |
4609 | return 0; | |
4610 | } | |
252fbfc8 | 4611 | |
25289eb2 PA |
4612 | stop_callback (lwp, NULL); |
4613 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4614 | } |
4615 | else | |
4616 | { | |
4617 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4618 | |
d90e17a7 PA |
4619 | if (debug_linux_nat) |
4620 | { | |
e09875d4 | 4621 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4622 | fprintf_unfiltered (gdb_stdlog, |
4623 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4624 | target_pid_to_str (lwp->ptid)); |
4625 | else | |
3e43a32a MS |
4626 | fprintf_unfiltered (gdb_stdlog, |
4627 | "LNSL: already stopped/no " | |
4628 | "stop_requested yet %s\n", | |
d90e17a7 | 4629 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4630 | } |
4631 | } | |
4c28f408 PA |
4632 | return 0; |
4633 | } | |
4634 | ||
4635 | static void | |
1eab8a48 | 4636 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 | 4637 | { |
bfedc46a PA |
4638 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4639 | } | |
4640 | ||
4641 | static void | |
4642 | linux_nat_interrupt (struct target_ops *self, ptid_t ptid) | |
4643 | { | |
4644 | if (non_stop) | |
d90e17a7 | 4645 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4646 | else |
bfedc46a | 4647 | linux_ops->to_interrupt (linux_ops, ptid); |
4c28f408 PA |
4648 | } |
4649 | ||
d90e17a7 | 4650 | static void |
de90e03d | 4651 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4652 | { |
4653 | /* Unregister from the event loop. */ | |
9debeba0 | 4654 | if (linux_nat_is_async_p (self)) |
6a3753b3 | 4655 | linux_nat_async (self, 0); |
d90e17a7 | 4656 | |
d90e17a7 | 4657 | if (linux_ops->to_close) |
de90e03d | 4658 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4659 | |
4660 | super_close (self); | |
d90e17a7 PA |
4661 | } |
4662 | ||
c0694254 PA |
4663 | /* When requests are passed down from the linux-nat layer to the |
4664 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4665 | used. The address space pointer is stored in the inferior object, | |
4666 | but the common code that is passed such ptid can't tell whether | |
4667 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4668 | look up the "main" process id from the lwp here. */ | |
4669 | ||
70221824 | 4670 | static struct address_space * |
c0694254 PA |
4671 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4672 | { | |
4673 | struct lwp_info *lwp; | |
4674 | struct inferior *inf; | |
4675 | int pid; | |
4676 | ||
dfd4cc63 | 4677 | if (ptid_get_lwp (ptid) == 0) |
c0694254 PA |
4678 | { |
4679 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4680 | tgid. */ | |
4681 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4682 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4683 | } |
4684 | else | |
4685 | { | |
4686 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4687 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4688 | } |
4689 | ||
4690 | inf = find_inferior_pid (pid); | |
4691 | gdb_assert (inf != NULL); | |
4692 | return inf->aspace; | |
4693 | } | |
4694 | ||
dc146f7c VP |
4695 | /* Return the cached value of the processor core for thread PTID. */ |
4696 | ||
70221824 | 4697 | static int |
dc146f7c VP |
4698 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4699 | { | |
4700 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4701 | |
dc146f7c VP |
4702 | if (info) |
4703 | return info->core; | |
4704 | return -1; | |
4705 | } | |
4706 | ||
7a6a1731 GB |
4707 | /* Implementation of to_filesystem_is_local. */ |
4708 | ||
4709 | static int | |
4710 | linux_nat_filesystem_is_local (struct target_ops *ops) | |
4711 | { | |
4712 | struct inferior *inf = current_inferior (); | |
4713 | ||
4714 | if (inf->fake_pid_p || inf->pid == 0) | |
4715 | return 1; | |
4716 | ||
4717 | return linux_ns_same (inf->pid, LINUX_NS_MNT); | |
4718 | } | |
4719 | ||
4720 | /* Convert the INF argument passed to a to_fileio_* method | |
4721 | to a process ID suitable for passing to its corresponding | |
4722 | linux_mntns_* function. If INF is non-NULL then the | |
4723 | caller is requesting the filesystem seen by INF. If INF | |
4724 | is NULL then the caller is requesting the filesystem seen | |
4725 | by the GDB. We fall back to GDB's filesystem in the case | |
4726 | that INF is non-NULL but its PID is unknown. */ | |
4727 | ||
4728 | static pid_t | |
4729 | linux_nat_fileio_pid_of (struct inferior *inf) | |
4730 | { | |
4731 | if (inf == NULL || inf->fake_pid_p || inf->pid == 0) | |
4732 | return getpid (); | |
4733 | else | |
4734 | return inf->pid; | |
4735 | } | |
4736 | ||
4737 | /* Implementation of to_fileio_open. */ | |
4738 | ||
4739 | static int | |
4740 | linux_nat_fileio_open (struct target_ops *self, | |
4741 | struct inferior *inf, const char *filename, | |
4313b8c0 GB |
4742 | int flags, int mode, int warn_if_slow, |
4743 | int *target_errno) | |
7a6a1731 GB |
4744 | { |
4745 | int nat_flags; | |
4746 | mode_t nat_mode; | |
4747 | int fd; | |
4748 | ||
4749 | if (fileio_to_host_openflags (flags, &nat_flags) == -1 | |
4750 | || fileio_to_host_mode (mode, &nat_mode) == -1) | |
4751 | { | |
4752 | *target_errno = FILEIO_EINVAL; | |
4753 | return -1; | |
4754 | } | |
4755 | ||
4756 | fd = linux_mntns_open_cloexec (linux_nat_fileio_pid_of (inf), | |
4757 | filename, nat_flags, nat_mode); | |
4758 | if (fd == -1) | |
4759 | *target_errno = host_to_fileio_error (errno); | |
4760 | ||
4761 | return fd; | |
4762 | } | |
4763 | ||
4764 | /* Implementation of to_fileio_readlink. */ | |
4765 | ||
4766 | static char * | |
4767 | linux_nat_fileio_readlink (struct target_ops *self, | |
4768 | struct inferior *inf, const char *filename, | |
4769 | int *target_errno) | |
4770 | { | |
4771 | char buf[PATH_MAX]; | |
4772 | int len; | |
4773 | char *ret; | |
4774 | ||
4775 | len = linux_mntns_readlink (linux_nat_fileio_pid_of (inf), | |
4776 | filename, buf, sizeof (buf)); | |
4777 | if (len < 0) | |
4778 | { | |
4779 | *target_errno = host_to_fileio_error (errno); | |
4780 | return NULL; | |
4781 | } | |
4782 | ||
224c3ddb | 4783 | ret = (char *) xmalloc (len + 1); |
7a6a1731 GB |
4784 | memcpy (ret, buf, len); |
4785 | ret[len] = '\0'; | |
4786 | return ret; | |
4787 | } | |
4788 | ||
4789 | /* Implementation of to_fileio_unlink. */ | |
4790 | ||
4791 | static int | |
4792 | linux_nat_fileio_unlink (struct target_ops *self, | |
4793 | struct inferior *inf, const char *filename, | |
4794 | int *target_errno) | |
4795 | { | |
4796 | int ret; | |
4797 | ||
4798 | ret = linux_mntns_unlink (linux_nat_fileio_pid_of (inf), | |
4799 | filename); | |
4800 | if (ret == -1) | |
4801 | *target_errno = host_to_fileio_error (errno); | |
4802 | ||
4803 | return ret; | |
4804 | } | |
4805 | ||
f973ed9c DJ |
4806 | void |
4807 | linux_nat_add_target (struct target_ops *t) | |
4808 | { | |
f973ed9c DJ |
4809 | /* Save the provided single-threaded target. We save this in a separate |
4810 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4811 | may have saved a pointer to T; we want to use it for the final | |
4812 | process stratum target. */ | |
4813 | linux_ops_saved = *t; | |
4814 | linux_ops = &linux_ops_saved; | |
4815 | ||
4816 | /* Override some methods for multithreading. */ | |
b84876c2 | 4817 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4818 | t->to_attach = linux_nat_attach; |
4819 | t->to_detach = linux_nat_detach; | |
4820 | t->to_resume = linux_nat_resume; | |
4821 | t->to_wait = linux_nat_wait; | |
2455069d | 4822 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4823 | t->to_xfer_partial = linux_nat_xfer_partial; |
4824 | t->to_kill = linux_nat_kill; | |
4825 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4826 | t->to_thread_alive = linux_nat_thread_alive; | |
8a06aea7 | 4827 | t->to_update_thread_list = linux_nat_update_thread_list; |
f973ed9c | 4828 | t->to_pid_to_str = linux_nat_pid_to_str; |
4694da01 | 4829 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4830 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4831 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4832 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4833 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
faf09f01 PA |
4834 | t->to_stopped_by_sw_breakpoint = linux_nat_stopped_by_sw_breakpoint; |
4835 | t->to_supports_stopped_by_sw_breakpoint = linux_nat_supports_stopped_by_sw_breakpoint; | |
4836 | t->to_stopped_by_hw_breakpoint = linux_nat_stopped_by_hw_breakpoint; | |
4837 | t->to_supports_stopped_by_hw_breakpoint = linux_nat_supports_stopped_by_hw_breakpoint; | |
f973ed9c | 4838 | |
b84876c2 PA |
4839 | t->to_can_async_p = linux_nat_can_async_p; |
4840 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4841 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
fbea99ea | 4842 | t->to_always_non_stop_p = linux_nat_always_non_stop_p; |
b84876c2 | 4843 | t->to_async = linux_nat_async; |
b84876c2 PA |
4844 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4845 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4846 | |
4847 | super_close = t->to_close; | |
d90e17a7 | 4848 | t->to_close = linux_nat_close; |
b84876c2 | 4849 | |
4c28f408 | 4850 | t->to_stop = linux_nat_stop; |
bfedc46a | 4851 | t->to_interrupt = linux_nat_interrupt; |
4c28f408 | 4852 | |
d90e17a7 PA |
4853 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4854 | ||
03583c20 UW |
4855 | t->to_supports_disable_randomization |
4856 | = linux_nat_supports_disable_randomization; | |
4857 | ||
dc146f7c VP |
4858 | t->to_core_of_thread = linux_nat_core_of_thread; |
4859 | ||
7a6a1731 GB |
4860 | t->to_filesystem_is_local = linux_nat_filesystem_is_local; |
4861 | t->to_fileio_open = linux_nat_fileio_open; | |
4862 | t->to_fileio_readlink = linux_nat_fileio_readlink; | |
4863 | t->to_fileio_unlink = linux_nat_fileio_unlink; | |
4864 | ||
f973ed9c DJ |
4865 | /* We don't change the stratum; this target will sit at |
4866 | process_stratum and thread_db will set at thread_stratum. This | |
4867 | is a little strange, since this is a multi-threaded-capable | |
4868 | target, but we want to be on the stack below thread_db, and we | |
4869 | also want to be used for single-threaded processes. */ | |
4870 | ||
4871 | add_target (t); | |
f973ed9c DJ |
4872 | } |
4873 | ||
9f0bdab8 DJ |
4874 | /* Register a method to call whenever a new thread is attached. */ |
4875 | void | |
7b50312a PA |
4876 | linux_nat_set_new_thread (struct target_ops *t, |
4877 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4878 | { |
4879 | /* Save the pointer. We only support a single registered instance | |
4880 | of the GNU/Linux native target, so we do not need to map this to | |
4881 | T. */ | |
4882 | linux_nat_new_thread = new_thread; | |
4883 | } | |
4884 | ||
26cb8b7c PA |
4885 | /* See declaration in linux-nat.h. */ |
4886 | ||
4887 | void | |
4888 | linux_nat_set_new_fork (struct target_ops *t, | |
4889 | linux_nat_new_fork_ftype *new_fork) | |
4890 | { | |
4891 | /* Save the pointer. */ | |
4892 | linux_nat_new_fork = new_fork; | |
4893 | } | |
4894 | ||
4895 | /* See declaration in linux-nat.h. */ | |
4896 | ||
4897 | void | |
4898 | linux_nat_set_forget_process (struct target_ops *t, | |
4899 | linux_nat_forget_process_ftype *fn) | |
4900 | { | |
4901 | /* Save the pointer. */ | |
4902 | linux_nat_forget_process_hook = fn; | |
4903 | } | |
4904 | ||
4905 | /* See declaration in linux-nat.h. */ | |
4906 | ||
4907 | void | |
4908 | linux_nat_forget_process (pid_t pid) | |
4909 | { | |
4910 | if (linux_nat_forget_process_hook != NULL) | |
4911 | linux_nat_forget_process_hook (pid); | |
4912 | } | |
4913 | ||
5b009018 PA |
4914 | /* Register a method that converts a siginfo object between the layout |
4915 | that ptrace returns, and the layout in the architecture of the | |
4916 | inferior. */ | |
4917 | void | |
4918 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4919 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4920 | gdb_byte *, |
4921 | int)) | |
4922 | { | |
4923 | /* Save the pointer. */ | |
4924 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4925 | } | |
4926 | ||
7b50312a PA |
4927 | /* Register a method to call prior to resuming a thread. */ |
4928 | ||
4929 | void | |
4930 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4931 | void (*prepare_to_resume) (struct lwp_info *)) | |
4932 | { | |
4933 | /* Save the pointer. */ | |
4934 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4935 | } | |
4936 | ||
f865ee35 JK |
4937 | /* See linux-nat.h. */ |
4938 | ||
4939 | int | |
4940 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4941 | { |
da559b09 | 4942 | int pid; |
9f0bdab8 | 4943 | |
dfd4cc63 | 4944 | pid = ptid_get_lwp (ptid); |
da559b09 | 4945 | if (pid == 0) |
dfd4cc63 | 4946 | pid = ptid_get_pid (ptid); |
f865ee35 | 4947 | |
da559b09 JK |
4948 | errno = 0; |
4949 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4950 | if (errno != 0) | |
4951 | { | |
4952 | memset (siginfo, 0, sizeof (*siginfo)); | |
4953 | return 0; | |
4954 | } | |
f865ee35 | 4955 | return 1; |
9f0bdab8 DJ |
4956 | } |
4957 | ||
7b669087 GB |
4958 | /* See nat/linux-nat.h. */ |
4959 | ||
4960 | ptid_t | |
4961 | current_lwp_ptid (void) | |
4962 | { | |
4963 | gdb_assert (ptid_lwp_p (inferior_ptid)); | |
4964 | return inferior_ptid; | |
4965 | } | |
4966 | ||
2c0b251b PA |
4967 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4968 | extern initialize_file_ftype _initialize_linux_nat; | |
4969 | ||
d6b0e80f AC |
4970 | void |
4971 | _initialize_linux_nat (void) | |
4972 | { | |
ccce17b0 YQ |
4973 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4974 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4975 | Set debugging of GNU/Linux lwp module."), _("\ |
4976 | Show debugging of GNU/Linux lwp module."), _("\ | |
4977 | Enables printf debugging output."), | |
ccce17b0 YQ |
4978 | NULL, |
4979 | show_debug_linux_nat, | |
4980 | &setdebuglist, &showdebuglist); | |
b84876c2 | 4981 | |
7a6a1731 GB |
4982 | add_setshow_boolean_cmd ("linux-namespaces", class_maintenance, |
4983 | &debug_linux_namespaces, _("\ | |
4984 | Set debugging of GNU/Linux namespaces module."), _("\ | |
4985 | Show debugging of GNU/Linux namespaces module."), _("\ | |
4986 | Enables printf debugging output."), | |
4987 | NULL, | |
4988 | NULL, | |
4989 | &setdebuglist, &showdebuglist); | |
4990 | ||
b84876c2 | 4991 | /* Save this mask as the default. */ |
d6b0e80f AC |
4992 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4993 | ||
7feb7d06 PA |
4994 | /* Install a SIGCHLD handler. */ |
4995 | sigchld_action.sa_handler = sigchld_handler; | |
4996 | sigemptyset (&sigchld_action.sa_mask); | |
4997 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
4998 | |
4999 | /* Make it the default. */ | |
7feb7d06 | 5000 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5001 | |
5002 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5003 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5004 | sigdelset (&suspend_mask, SIGCHLD); | |
5005 | ||
7feb7d06 | 5006 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5007 | } |
5008 | \f | |
5009 | ||
5010 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5011 | the GNU/Linux Threads library and therefore doesn't really belong | |
5012 | here. */ | |
5013 | ||
5014 | /* Read variable NAME in the target and return its value if found. | |
5015 | Otherwise return zero. It is assumed that the type of the variable | |
5016 | is `int'. */ | |
5017 | ||
5018 | static int | |
5019 | get_signo (const char *name) | |
5020 | { | |
3b7344d5 | 5021 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5022 | int signo; |
5023 | ||
5024 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5025 | if (ms.minsym == NULL) |
d6b0e80f AC |
5026 | return 0; |
5027 | ||
77e371c0 | 5028 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5029 | sizeof (signo)) != 0) |
5030 | return 0; | |
5031 | ||
5032 | return signo; | |
5033 | } | |
5034 | ||
5035 | /* Return the set of signals used by the threads library in *SET. */ | |
5036 | ||
5037 | void | |
5038 | lin_thread_get_thread_signals (sigset_t *set) | |
5039 | { | |
5040 | struct sigaction action; | |
5041 | int restart, cancel; | |
5042 | ||
b84876c2 | 5043 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5044 | sigemptyset (set); |
5045 | ||
5046 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5047 | cancel = get_signo ("__pthread_sig_cancel"); |
5048 | ||
5049 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5050 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5051 | not provide any way for the debugger to query the signal numbers - | |
5052 | fortunately they don't change! */ | |
5053 | ||
d6b0e80f | 5054 | if (restart == 0) |
17fbb0bd | 5055 | restart = __SIGRTMIN; |
d6b0e80f | 5056 | |
d6b0e80f | 5057 | if (cancel == 0) |
17fbb0bd | 5058 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5059 | |
5060 | sigaddset (set, restart); | |
5061 | sigaddset (set, cancel); | |
5062 | ||
5063 | /* The GNU/Linux Threads library makes terminating threads send a | |
5064 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5065 | those (to prevent them from terminating GDB itself, which is | |
5066 | likely to be their default action) and treat them the same way as | |
5067 | SIGCHLD. */ | |
5068 | ||
5069 | action.sa_handler = sigchld_handler; | |
5070 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5071 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5072 | sigaction (cancel, &action, NULL); |
5073 | ||
5074 | /* We block the "cancel" signal throughout this code ... */ | |
5075 | sigaddset (&blocked_mask, cancel); | |
5076 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5077 | ||
5078 | /* ... except during a sigsuspend. */ | |
5079 | sigdelset (&suspend_mask, cancel); | |
5080 | } |