Commit | Line | Data |
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3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
ecd75fc8 | 3 | Copyright (C) 2001-2014 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" | |
22 | #include "target.h" | |
96d7229d LM |
23 | #include "nat/linux-nat.h" |
24 | #include "nat/linux-waitpid.h" | |
0e9f083f | 25 | #include <string.h> |
3993f6b1 | 26 | #include "gdb_wait.h" |
d6b0e80f AC |
27 | #include "gdb_assert.h" |
28 | #ifdef HAVE_TKILL_SYSCALL | |
29 | #include <unistd.h> | |
30 | #include <sys/syscall.h> | |
31 | #endif | |
3993f6b1 | 32 | #include <sys/ptrace.h> |
0274a8ce | 33 | #include "linux-nat.h" |
af96c192 | 34 | #include "linux-ptrace.h" |
13da1c97 | 35 | #include "linux-procfs.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 */ | |
1777feb0 | 49 | #include "gdbthread.h" /* for struct thread_info etc. */ |
53ce3c39 | 50 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 51 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
52 | #include "inf-loop.h" |
53 | #include "event-loop.h" | |
54 | #include "event-top.h" | |
07e059b5 VP |
55 | #include <pwd.h> |
56 | #include <sys/types.h> | |
2978b111 | 57 | #include <dirent.h> |
07e059b5 | 58 | #include "xml-support.h" |
191c4426 | 59 | #include "terminal.h" |
efcbbd14 | 60 | #include <sys/vfs.h> |
6c95b8df | 61 | #include "solib.h" |
d26e3629 | 62 | #include "linux-osdata.h" |
6432734d | 63 | #include "linux-tdep.h" |
7dcd53a0 | 64 | #include "symfile.h" |
5808517f YQ |
65 | #include "agent.h" |
66 | #include "tracepoint.h" | |
87b0bb13 JK |
67 | #include "exceptions.h" |
68 | #include "linux-ptrace.h" | |
69 | #include "buffer.h" | |
6ecd4729 | 70 | #include "target-descriptions.h" |
614c279d | 71 | #include "filestuff.h" |
efcbbd14 UW |
72 | |
73 | #ifndef SPUFS_MAGIC | |
74 | #define SPUFS_MAGIC 0x23c9b64e | |
75 | #endif | |
dba24537 | 76 | |
10568435 JK |
77 | #ifdef HAVE_PERSONALITY |
78 | # include <sys/personality.h> | |
79 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
80 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
81 | # endif | |
82 | #endif /* HAVE_PERSONALITY */ | |
83 | ||
1777feb0 | 84 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
85 | |
86 | Waiting for events in sync mode | |
87 | =============================== | |
88 | ||
89 | When waiting for an event in a specific thread, we just use waitpid, passing | |
90 | the specific pid, and not passing WNOHANG. | |
91 | ||
1777feb0 | 92 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 93 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 94 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
95 | miss an event. The solution is to use non-blocking waitpid, together with |
96 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 97 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
98 | flag to check for events in cloned processes. If nothing is found, we use |
99 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
100 | happened to a child process -- and SIGCHLD will be delivered both for events | |
101 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
102 | an event, we get back to calling nonblocking waitpid with and without |
103 | __WCLONED. | |
8a77dff3 VP |
104 | |
105 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 106 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
107 | blocked, the signal becomes pending and sigsuspend immediately |
108 | notices it and returns. | |
109 | ||
110 | Waiting for events in async mode | |
111 | ================================ | |
112 | ||
7feb7d06 PA |
113 | In async mode, GDB should always be ready to handle both user input |
114 | and target events, so neither blocking waitpid nor sigsuspend are | |
115 | viable options. Instead, we should asynchronously notify the GDB main | |
116 | event loop whenever there's an unprocessed event from the target. We | |
117 | detect asynchronous target events by handling SIGCHLD signals. To | |
118 | notify the event loop about target events, the self-pipe trick is used | |
119 | --- a pipe is registered as waitable event source in the event loop, | |
120 | the event loop select/poll's on the read end of this pipe (as well on | |
121 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
122 | byte to this pipe. This is more portable than relying on | |
123 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
124 | emulates them with select/poll+sigprocmask, and that is racy | |
125 | (a.k.a. plain broken). | |
126 | ||
127 | Obviously, if we fail to notify the event loop if there's a target | |
128 | event, it's bad. OTOH, if we notify the event loop when there's no | |
129 | event from the target, linux_nat_wait will detect that there's no real | |
130 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
131 | This is mostly harmless, but it will waste time and is better avoided. | |
132 | ||
133 | The main design point is that every time GDB is outside linux-nat.c, | |
134 | we have a SIGCHLD handler installed that is called when something | |
135 | happens to the target and notifies the GDB event loop. Whenever GDB | |
136 | core decides to handle the event, and calls into linux-nat.c, we | |
137 | process things as in sync mode, except that the we never block in | |
138 | sigsuspend. | |
139 | ||
140 | While processing an event, we may end up momentarily blocked in | |
141 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
142 | return quickly. E.g., in all-stop mode, before reporting to the core | |
143 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
144 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
145 | Note that this is different from blocking indefinitely waiting for the | |
146 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
147 | |
148 | Use of signals | |
149 | ============== | |
150 | ||
151 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
152 | signal is not entirely significant; we just need for a signal to be delivered, | |
153 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
154 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
155 | be queued once; we do not keep track of other sources of SIGSTOP. | |
156 | ||
157 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
158 | use them, because they have special behavior when the signal is generated - | |
159 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
160 | kills the entire thread group. | |
161 | ||
162 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
163 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
164 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
165 | ||
166 | We could use a real-time signal instead. This would solve those problems; we | |
167 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
168 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
169 | generates it, and there are races with trying to find a signal that is not | |
170 | blocked. */ | |
a0ef4274 | 171 | |
dba24537 AC |
172 | #ifndef O_LARGEFILE |
173 | #define O_LARGEFILE 0 | |
174 | #endif | |
0274a8ce | 175 | |
10d6c8cd DJ |
176 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
177 | the use of the multi-threaded target. */ | |
178 | static struct target_ops *linux_ops; | |
f973ed9c | 179 | static struct target_ops linux_ops_saved; |
10d6c8cd | 180 | |
9f0bdab8 | 181 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
182 | static void (*linux_nat_new_thread) (struct lwp_info *); |
183 | ||
26cb8b7c PA |
184 | /* The method to call, if any, when a new fork is attached. */ |
185 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
186 | ||
187 | /* The method to call, if any, when a process is no longer | |
188 | attached. */ | |
189 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
190 | ||
7b50312a PA |
191 | /* Hook to call prior to resuming a thread. */ |
192 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 193 | |
5b009018 PA |
194 | /* The method to call, if any, when the siginfo object needs to be |
195 | converted between the layout returned by ptrace, and the layout in | |
196 | the architecture of the inferior. */ | |
a5362b9a | 197 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
198 | gdb_byte *, |
199 | int); | |
200 | ||
ac264b3b MS |
201 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
202 | Called by our to_xfer_partial. */ | |
4ac248ca | 203 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 204 | |
ccce17b0 | 205 | static unsigned int debug_linux_nat; |
920d2a44 AC |
206 | static void |
207 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
208 | struct cmd_list_element *c, const char *value) | |
209 | { | |
210 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
211 | value); | |
212 | } | |
d6b0e80f | 213 | |
ae087d01 DJ |
214 | struct simple_pid_list |
215 | { | |
216 | int pid; | |
3d799a95 | 217 | int status; |
ae087d01 DJ |
218 | struct simple_pid_list *next; |
219 | }; | |
220 | struct simple_pid_list *stopped_pids; | |
221 | ||
3dd5b83d PA |
222 | /* Async mode support. */ |
223 | ||
b84876c2 PA |
224 | /* The read/write ends of the pipe registered as waitable file in the |
225 | event loop. */ | |
226 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
227 | ||
7feb7d06 | 228 | /* Flush the event pipe. */ |
b84876c2 | 229 | |
7feb7d06 PA |
230 | static void |
231 | async_file_flush (void) | |
b84876c2 | 232 | { |
7feb7d06 PA |
233 | int ret; |
234 | char buf; | |
b84876c2 | 235 | |
7feb7d06 | 236 | do |
b84876c2 | 237 | { |
7feb7d06 | 238 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 239 | } |
7feb7d06 | 240 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
241 | } |
242 | ||
7feb7d06 PA |
243 | /* Put something (anything, doesn't matter what, or how much) in event |
244 | pipe, so that the select/poll in the event-loop realizes we have | |
245 | something to process. */ | |
252fbfc8 | 246 | |
b84876c2 | 247 | static void |
7feb7d06 | 248 | async_file_mark (void) |
b84876c2 | 249 | { |
7feb7d06 | 250 | int ret; |
b84876c2 | 251 | |
7feb7d06 PA |
252 | /* It doesn't really matter what the pipe contains, as long we end |
253 | up with something in it. Might as well flush the previous | |
254 | left-overs. */ | |
255 | async_file_flush (); | |
b84876c2 | 256 | |
7feb7d06 | 257 | do |
b84876c2 | 258 | { |
7feb7d06 | 259 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 260 | } |
7feb7d06 | 261 | while (ret == -1 && errno == EINTR); |
b84876c2 | 262 | |
7feb7d06 PA |
263 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
264 | be awakened anyway. */ | |
b84876c2 PA |
265 | } |
266 | ||
7feb7d06 | 267 | static void linux_nat_async (void (*callback) |
3e43a32a MS |
268 | (enum inferior_event_type event_type, |
269 | void *context), | |
7feb7d06 | 270 | void *context); |
7feb7d06 PA |
271 | static int kill_lwp (int lwpid, int signo); |
272 | ||
273 | static int stop_callback (struct lwp_info *lp, void *data); | |
274 | ||
275 | static void block_child_signals (sigset_t *prev_mask); | |
276 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
277 | |
278 | struct lwp_info; | |
279 | static struct lwp_info *add_lwp (ptid_t ptid); | |
280 | static void purge_lwp_list (int pid); | |
4403d8e9 | 281 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
282 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
283 | ||
ae087d01 DJ |
284 | \f |
285 | /* Trivial list manipulation functions to keep track of a list of | |
286 | new stopped processes. */ | |
287 | static void | |
3d799a95 | 288 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
289 | { |
290 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 291 | |
ae087d01 | 292 | new_pid->pid = pid; |
3d799a95 | 293 | new_pid->status = status; |
ae087d01 DJ |
294 | new_pid->next = *listp; |
295 | *listp = new_pid; | |
296 | } | |
297 | ||
84636d28 PA |
298 | static int |
299 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
300 | { | |
301 | struct simple_pid_list *p; | |
302 | ||
303 | for (p = list; p != NULL; p = p->next) | |
304 | if (p->pid == pid) | |
305 | return 1; | |
306 | return 0; | |
307 | } | |
308 | ||
ae087d01 | 309 | static int |
46a96992 | 310 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
311 | { |
312 | struct simple_pid_list **p; | |
313 | ||
314 | for (p = listp; *p != NULL; p = &(*p)->next) | |
315 | if ((*p)->pid == pid) | |
316 | { | |
317 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 318 | |
46a96992 | 319 | *statusp = (*p)->status; |
ae087d01 DJ |
320 | xfree (*p); |
321 | *p = next; | |
322 | return 1; | |
323 | } | |
324 | return 0; | |
325 | } | |
326 | ||
96d7229d LM |
327 | /* Initialize ptrace warnings and check for supported ptrace |
328 | features given PID. */ | |
3993f6b1 DJ |
329 | |
330 | static void | |
96d7229d | 331 | linux_init_ptrace (pid_t pid) |
3993f6b1 | 332 | { |
96d7229d LM |
333 | linux_enable_event_reporting (pid); |
334 | linux_ptrace_init_warnings (); | |
4de4c07c DJ |
335 | } |
336 | ||
6d8fd2b7 UW |
337 | static void |
338 | linux_child_post_attach (int pid) | |
4de4c07c | 339 | { |
96d7229d | 340 | linux_init_ptrace (pid); |
4de4c07c DJ |
341 | } |
342 | ||
10d6c8cd | 343 | static void |
4de4c07c DJ |
344 | linux_child_post_startup_inferior (ptid_t ptid) |
345 | { | |
96d7229d | 346 | linux_init_ptrace (ptid_get_pid (ptid)); |
4de4c07c DJ |
347 | } |
348 | ||
4403d8e9 JK |
349 | /* Return the number of known LWPs in the tgid given by PID. */ |
350 | ||
351 | static int | |
352 | num_lwps (int pid) | |
353 | { | |
354 | int count = 0; | |
355 | struct lwp_info *lp; | |
356 | ||
357 | for (lp = lwp_list; lp; lp = lp->next) | |
358 | if (ptid_get_pid (lp->ptid) == pid) | |
359 | count++; | |
360 | ||
361 | return count; | |
362 | } | |
363 | ||
364 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
365 | ||
366 | static void | |
367 | delete_lwp_cleanup (void *lp_voidp) | |
368 | { | |
369 | struct lwp_info *lp = lp_voidp; | |
370 | ||
371 | delete_lwp (lp->ptid); | |
372 | } | |
373 | ||
6d8fd2b7 | 374 | static int |
07107ca6 LM |
375 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
376 | int detach_fork) | |
3993f6b1 | 377 | { |
9016a515 | 378 | int has_vforked; |
4de4c07c DJ |
379 | int parent_pid, child_pid; |
380 | ||
e58b0e63 PA |
381 | has_vforked = (inferior_thread ()->pending_follow.kind |
382 | == TARGET_WAITKIND_VFORKED); | |
383 | parent_pid = ptid_get_lwp (inferior_ptid); | |
d3587048 | 384 | if (parent_pid == 0) |
e58b0e63 | 385 | parent_pid = ptid_get_pid (inferior_ptid); |
dfd4cc63 LM |
386 | child_pid |
387 | = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid); | |
4de4c07c | 388 | |
6c95b8df PA |
389 | if (has_vforked |
390 | && !non_stop /* Non-stop always resumes both branches. */ | |
391 | && (!target_is_async_p () || sync_execution) | |
392 | && !(follow_child || detach_fork || sched_multi)) | |
393 | { | |
394 | /* The parent stays blocked inside the vfork syscall until the | |
395 | child execs or exits. If we don't let the child run, then | |
396 | the parent stays blocked. If we're telling the parent to run | |
397 | in the foreground, the user will not be able to ctrl-c to get | |
398 | back the terminal, effectively hanging the debug session. */ | |
ac74f770 MS |
399 | fprintf_filtered (gdb_stderr, _("\ |
400 | Can not resume the parent process over vfork in the foreground while\n\ | |
401 | holding the child stopped. Try \"set detach-on-fork\" or \ | |
402 | \"set schedule-multiple\".\n")); | |
403 | /* FIXME output string > 80 columns. */ | |
6c95b8df PA |
404 | return 1; |
405 | } | |
406 | ||
4de4c07c DJ |
407 | if (! follow_child) |
408 | { | |
6c95b8df | 409 | struct lwp_info *child_lp = NULL; |
4de4c07c | 410 | |
1777feb0 | 411 | /* We're already attached to the parent, by default. */ |
4de4c07c | 412 | |
ac264b3b MS |
413 | /* Detach new forked process? */ |
414 | if (detach_fork) | |
f75c00e4 | 415 | { |
4403d8e9 JK |
416 | struct cleanup *old_chain; |
417 | ||
6c95b8df PA |
418 | /* Before detaching from the child, remove all breakpoints |
419 | from it. If we forked, then this has already been taken | |
420 | care of by infrun.c. If we vforked however, any | |
421 | breakpoint inserted in the parent is visible in the | |
422 | child, even those added while stopped in a vfork | |
423 | catchpoint. This will remove the breakpoints from the | |
424 | parent also, but they'll be reinserted below. */ | |
425 | if (has_vforked) | |
426 | { | |
427 | /* keep breakpoints list in sync. */ | |
dfd4cc63 | 428 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
6c95b8df PA |
429 | } |
430 | ||
e85a822c | 431 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
432 | { |
433 | target_terminal_ours (); | |
434 | fprintf_filtered (gdb_stdlog, | |
3e43a32a MS |
435 | "Detaching after fork from " |
436 | "child process %d.\n", | |
ac264b3b MS |
437 | child_pid); |
438 | } | |
4de4c07c | 439 | |
4403d8e9 JK |
440 | old_chain = save_inferior_ptid (); |
441 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
442 | ||
443 | child_lp = add_lwp (inferior_ptid); | |
444 | child_lp->stopped = 1; | |
445 | child_lp->last_resume_kind = resume_stop; | |
446 | make_cleanup (delete_lwp_cleanup, child_lp); | |
447 | ||
4403d8e9 JK |
448 | if (linux_nat_prepare_to_resume != NULL) |
449 | linux_nat_prepare_to_resume (child_lp); | |
ac264b3b | 450 | ptrace (PTRACE_DETACH, child_pid, 0, 0); |
4403d8e9 JK |
451 | |
452 | do_cleanups (old_chain); | |
ac264b3b MS |
453 | } |
454 | else | |
455 | { | |
77435e4c | 456 | struct inferior *parent_inf, *child_inf; |
2277426b | 457 | struct cleanup *old_chain; |
7f9f62ba PA |
458 | |
459 | /* Add process to GDB's tables. */ | |
77435e4c PA |
460 | child_inf = add_inferior (child_pid); |
461 | ||
e58b0e63 | 462 | parent_inf = current_inferior (); |
77435e4c | 463 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 464 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
465 | child_inf->gdbarch = parent_inf->gdbarch; |
466 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7f9f62ba | 467 | |
2277426b | 468 | old_chain = save_inferior_ptid (); |
6c95b8df | 469 | save_current_program_space (); |
2277426b PA |
470 | |
471 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
472 | add_thread (inferior_ptid); | |
6c95b8df PA |
473 | child_lp = add_lwp (inferior_ptid); |
474 | child_lp->stopped = 1; | |
25289eb2 | 475 | child_lp->last_resume_kind = resume_stop; |
7dcd53a0 | 476 | child_inf->symfile_flags = SYMFILE_NO_READ; |
2277426b | 477 | |
6c95b8df PA |
478 | /* If this is a vfork child, then the address-space is |
479 | shared with the parent. */ | |
480 | if (has_vforked) | |
481 | { | |
482 | child_inf->pspace = parent_inf->pspace; | |
483 | child_inf->aspace = parent_inf->aspace; | |
484 | ||
485 | /* The parent will be frozen until the child is done | |
486 | with the shared region. Keep track of the | |
487 | parent. */ | |
488 | child_inf->vfork_parent = parent_inf; | |
489 | child_inf->pending_detach = 0; | |
490 | parent_inf->vfork_child = child_inf; | |
491 | parent_inf->pending_detach = 0; | |
492 | } | |
493 | else | |
494 | { | |
495 | child_inf->aspace = new_address_space (); | |
496 | child_inf->pspace = add_program_space (child_inf->aspace); | |
497 | child_inf->removable = 1; | |
498 | set_current_program_space (child_inf->pspace); | |
499 | clone_program_space (child_inf->pspace, parent_inf->pspace); | |
500 | ||
501 | /* Let the shared library layer (solib-svr4) learn about | |
502 | this new process, relocate the cloned exec, pull in | |
503 | shared libraries, and install the solib event | |
504 | breakpoint. If a "cloned-VM" event was propagated | |
505 | better throughout the core, this wouldn't be | |
506 | required. */ | |
268a4a75 | 507 | solib_create_inferior_hook (0); |
6c95b8df PA |
508 | } |
509 | ||
510 | /* Let the thread_db layer learn about this new process. */ | |
2277426b PA |
511 | check_for_thread_db (); |
512 | ||
513 | do_cleanups (old_chain); | |
ac264b3b | 514 | } |
9016a515 DJ |
515 | |
516 | if (has_vforked) | |
517 | { | |
3ced3da4 | 518 | struct lwp_info *parent_lp; |
6c95b8df PA |
519 | struct inferior *parent_inf; |
520 | ||
521 | parent_inf = current_inferior (); | |
522 | ||
523 | /* If we detached from the child, then we have to be careful | |
524 | to not insert breakpoints in the parent until the child | |
525 | is done with the shared memory region. However, if we're | |
526 | staying attached to the child, then we can and should | |
527 | insert breakpoints, so that we can debug it. A | |
528 | subsequent child exec or exit is enough to know when does | |
529 | the child stops using the parent's address space. */ | |
530 | parent_inf->waiting_for_vfork_done = detach_fork; | |
56710373 | 531 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
6c95b8df | 532 | |
3ced3da4 | 533 | parent_lp = find_lwp_pid (pid_to_ptid (parent_pid)); |
96d7229d | 534 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 535 | |
96d7229d | 536 | if (linux_supports_tracevforkdone ()) |
9016a515 | 537 | { |
6c95b8df PA |
538 | if (debug_linux_nat) |
539 | fprintf_unfiltered (gdb_stdlog, | |
540 | "LCFF: waiting for VFORK_DONE on %d\n", | |
541 | parent_pid); | |
3ced3da4 | 542 | parent_lp->stopped = 1; |
9016a515 | 543 | |
6c95b8df PA |
544 | /* We'll handle the VFORK_DONE event like any other |
545 | event, in target_wait. */ | |
9016a515 DJ |
546 | } |
547 | else | |
548 | { | |
549 | /* We can't insert breakpoints until the child has | |
550 | finished with the shared memory region. We need to | |
551 | wait until that happens. Ideal would be to just | |
552 | call: | |
553 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
554 | - waitpid (parent_pid, &status, __WALL); | |
555 | However, most architectures can't handle a syscall | |
556 | being traced on the way out if it wasn't traced on | |
557 | the way in. | |
558 | ||
559 | We might also think to loop, continuing the child | |
560 | until it exits or gets a SIGTRAP. One problem is | |
561 | that the child might call ptrace with PTRACE_TRACEME. | |
562 | ||
563 | There's no simple and reliable way to figure out when | |
564 | the vforked child will be done with its copy of the | |
565 | shared memory. We could step it out of the syscall, | |
566 | two instructions, let it go, and then single-step the | |
567 | parent once. When we have hardware single-step, this | |
568 | would work; with software single-step it could still | |
569 | be made to work but we'd have to be able to insert | |
570 | single-step breakpoints in the child, and we'd have | |
571 | to insert -just- the single-step breakpoint in the | |
572 | parent. Very awkward. | |
573 | ||
574 | In the end, the best we can do is to make sure it | |
575 | runs for a little while. Hopefully it will be out of | |
576 | range of any breakpoints we reinsert. Usually this | |
577 | is only the single-step breakpoint at vfork's return | |
578 | point. */ | |
579 | ||
6c95b8df PA |
580 | if (debug_linux_nat) |
581 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
582 | "LCFF: no VFORK_DONE " |
583 | "support, sleeping a bit\n"); | |
6c95b8df | 584 | |
9016a515 | 585 | usleep (10000); |
9016a515 | 586 | |
6c95b8df PA |
587 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
588 | and leave it pending. The next linux_nat_resume call | |
589 | will notice a pending event, and bypasses actually | |
590 | resuming the inferior. */ | |
3ced3da4 PA |
591 | parent_lp->status = 0; |
592 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
593 | parent_lp->stopped = 1; | |
6c95b8df PA |
594 | |
595 | /* If we're in async mode, need to tell the event loop | |
596 | there's something here to process. */ | |
597 | if (target_can_async_p ()) | |
598 | async_file_mark (); | |
599 | } | |
9016a515 | 600 | } |
4de4c07c | 601 | } |
3993f6b1 | 602 | else |
4de4c07c | 603 | { |
77435e4c | 604 | struct inferior *parent_inf, *child_inf; |
3ced3da4 | 605 | struct lwp_info *child_lp; |
6c95b8df | 606 | struct program_space *parent_pspace; |
4de4c07c | 607 | |
e85a822c | 608 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
609 | { |
610 | target_terminal_ours (); | |
6c95b8df | 611 | if (has_vforked) |
3e43a32a MS |
612 | fprintf_filtered (gdb_stdlog, |
613 | _("Attaching after process %d " | |
614 | "vfork to child process %d.\n"), | |
6c95b8df PA |
615 | parent_pid, child_pid); |
616 | else | |
3e43a32a MS |
617 | fprintf_filtered (gdb_stdlog, |
618 | _("Attaching after process %d " | |
619 | "fork to child process %d.\n"), | |
6c95b8df | 620 | parent_pid, child_pid); |
f75c00e4 | 621 | } |
4de4c07c | 622 | |
7a7d3353 PA |
623 | /* Add the new inferior first, so that the target_detach below |
624 | doesn't unpush the target. */ | |
625 | ||
77435e4c PA |
626 | child_inf = add_inferior (child_pid); |
627 | ||
e58b0e63 | 628 | parent_inf = current_inferior (); |
77435e4c | 629 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 630 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
631 | child_inf->gdbarch = parent_inf->gdbarch; |
632 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7a7d3353 | 633 | |
6c95b8df | 634 | parent_pspace = parent_inf->pspace; |
9016a515 | 635 | |
6c95b8df PA |
636 | /* If we're vforking, we want to hold on to the parent until the |
637 | child exits or execs. At child exec or exit time we can | |
638 | remove the old breakpoints from the parent and detach or | |
639 | resume debugging it. Otherwise, detach the parent now; we'll | |
640 | want to reuse it's program/address spaces, but we can't set | |
641 | them to the child before removing breakpoints from the | |
642 | parent, otherwise, the breakpoints module could decide to | |
643 | remove breakpoints from the wrong process (since they'd be | |
644 | assigned to the same address space). */ | |
9016a515 DJ |
645 | |
646 | if (has_vforked) | |
7f9f62ba | 647 | { |
6c95b8df PA |
648 | gdb_assert (child_inf->vfork_parent == NULL); |
649 | gdb_assert (parent_inf->vfork_child == NULL); | |
650 | child_inf->vfork_parent = parent_inf; | |
651 | child_inf->pending_detach = 0; | |
652 | parent_inf->vfork_child = child_inf; | |
653 | parent_inf->pending_detach = detach_fork; | |
654 | parent_inf->waiting_for_vfork_done = 0; | |
ac264b3b | 655 | } |
2277426b | 656 | else if (detach_fork) |
b84876c2 | 657 | target_detach (NULL, 0); |
4de4c07c | 658 | |
6c95b8df PA |
659 | /* Note that the detach above makes PARENT_INF dangling. */ |
660 | ||
661 | /* Add the child thread to the appropriate lists, and switch to | |
662 | this new thread, before cloning the program space, and | |
663 | informing the solib layer about this new process. */ | |
664 | ||
9f0bdab8 | 665 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
2277426b | 666 | add_thread (inferior_ptid); |
3ced3da4 PA |
667 | child_lp = add_lwp (inferior_ptid); |
668 | child_lp->stopped = 1; | |
25289eb2 | 669 | child_lp->last_resume_kind = resume_stop; |
6c95b8df PA |
670 | |
671 | /* If this is a vfork child, then the address-space is shared | |
672 | with the parent. If we detached from the parent, then we can | |
673 | reuse the parent's program/address spaces. */ | |
674 | if (has_vforked || detach_fork) | |
675 | { | |
676 | child_inf->pspace = parent_pspace; | |
677 | child_inf->aspace = child_inf->pspace->aspace; | |
678 | } | |
679 | else | |
680 | { | |
681 | child_inf->aspace = new_address_space (); | |
682 | child_inf->pspace = add_program_space (child_inf->aspace); | |
683 | child_inf->removable = 1; | |
7dcd53a0 | 684 | child_inf->symfile_flags = SYMFILE_NO_READ; |
6c95b8df PA |
685 | set_current_program_space (child_inf->pspace); |
686 | clone_program_space (child_inf->pspace, parent_pspace); | |
687 | ||
688 | /* Let the shared library layer (solib-svr4) learn about | |
689 | this new process, relocate the cloned exec, pull in | |
690 | shared libraries, and install the solib event breakpoint. | |
691 | If a "cloned-VM" event was propagated better throughout | |
692 | the core, this wouldn't be required. */ | |
268a4a75 | 693 | solib_create_inferior_hook (0); |
6c95b8df | 694 | } |
ac264b3b | 695 | |
6c95b8df | 696 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 697 | check_for_thread_db (); |
4de4c07c DJ |
698 | } |
699 | ||
700 | return 0; | |
701 | } | |
702 | ||
4de4c07c | 703 | \f |
77b06cd7 | 704 | static int |
6d8fd2b7 | 705 | linux_child_insert_fork_catchpoint (int pid) |
4de4c07c | 706 | { |
96d7229d | 707 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
708 | } |
709 | ||
eb73ad13 PA |
710 | static int |
711 | linux_child_remove_fork_catchpoint (int pid) | |
712 | { | |
713 | return 0; | |
714 | } | |
715 | ||
77b06cd7 | 716 | static int |
6d8fd2b7 | 717 | linux_child_insert_vfork_catchpoint (int pid) |
3993f6b1 | 718 | { |
96d7229d | 719 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
720 | } |
721 | ||
eb73ad13 PA |
722 | static int |
723 | linux_child_remove_vfork_catchpoint (int pid) | |
724 | { | |
725 | return 0; | |
726 | } | |
727 | ||
77b06cd7 | 728 | static int |
6d8fd2b7 | 729 | linux_child_insert_exec_catchpoint (int pid) |
3993f6b1 | 730 | { |
96d7229d | 731 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
732 | } |
733 | ||
eb73ad13 PA |
734 | static int |
735 | linux_child_remove_exec_catchpoint (int pid) | |
736 | { | |
737 | return 0; | |
738 | } | |
739 | ||
a96d9b2e SDJ |
740 | static int |
741 | linux_child_set_syscall_catchpoint (int pid, int needed, int any_count, | |
742 | int table_size, int *table) | |
743 | { | |
96d7229d | 744 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
745 | return 1; |
746 | ||
a96d9b2e SDJ |
747 | /* On GNU/Linux, we ignore the arguments. It means that we only |
748 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 749 | |
a96d9b2e SDJ |
750 | Also, we do not use the `table' information because we do not |
751 | filter system calls here. We let GDB do the logic for us. */ | |
752 | return 0; | |
753 | } | |
754 | ||
d6b0e80f AC |
755 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
756 | are processes sharing the same VM space. A multi-threaded process | |
757 | is basically a group of such processes. However, such a grouping | |
758 | is almost entirely a user-space issue; the kernel doesn't enforce | |
759 | such a grouping at all (this might change in the future). In | |
760 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
761 | Threads library) to provide such a grouping. | |
762 | ||
763 | It is perfectly well possible to write a multi-threaded application | |
764 | without the assistance of a threads library, by using the clone | |
765 | system call directly. This module should be able to give some | |
766 | rudimentary support for debugging such applications if developers | |
767 | specify the CLONE_PTRACE flag in the clone system call, and are | |
768 | using the Linux kernel 2.4 or above. | |
769 | ||
770 | Note that there are some peculiarities in GNU/Linux that affect | |
771 | this code: | |
772 | ||
773 | - In general one should specify the __WCLONE flag to waitpid in | |
774 | order to make it report events for any of the cloned processes | |
775 | (and leave it out for the initial process). However, if a cloned | |
776 | process has exited the exit status is only reported if the | |
777 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
778 | we cannot use it since GDB must work on older systems too. | |
779 | ||
780 | - When a traced, cloned process exits and is waited for by the | |
781 | debugger, the kernel reassigns it to the original parent and | |
782 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
783 | library doesn't notice this, which leads to the "zombie problem": | |
784 | When debugged a multi-threaded process that spawns a lot of | |
785 | threads will run out of processes, even if the threads exit, | |
786 | because the "zombies" stay around. */ | |
787 | ||
788 | /* List of known LWPs. */ | |
9f0bdab8 | 789 | struct lwp_info *lwp_list; |
d6b0e80f AC |
790 | \f |
791 | ||
d6b0e80f AC |
792 | /* Original signal mask. */ |
793 | static sigset_t normal_mask; | |
794 | ||
795 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
796 | _initialize_linux_nat. */ | |
797 | static sigset_t suspend_mask; | |
798 | ||
7feb7d06 PA |
799 | /* Signals to block to make that sigsuspend work. */ |
800 | static sigset_t blocked_mask; | |
801 | ||
802 | /* SIGCHLD action. */ | |
803 | struct sigaction sigchld_action; | |
b84876c2 | 804 | |
7feb7d06 PA |
805 | /* Block child signals (SIGCHLD and linux threads signals), and store |
806 | the previous mask in PREV_MASK. */ | |
84e46146 | 807 | |
7feb7d06 PA |
808 | static void |
809 | block_child_signals (sigset_t *prev_mask) | |
810 | { | |
811 | /* Make sure SIGCHLD is blocked. */ | |
812 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
813 | sigaddset (&blocked_mask, SIGCHLD); | |
814 | ||
815 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
816 | } | |
817 | ||
818 | /* Restore child signals mask, previously returned by | |
819 | block_child_signals. */ | |
820 | ||
821 | static void | |
822 | restore_child_signals_mask (sigset_t *prev_mask) | |
823 | { | |
824 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
825 | } | |
2455069d UW |
826 | |
827 | /* Mask of signals to pass directly to the inferior. */ | |
828 | static sigset_t pass_mask; | |
829 | ||
830 | /* Update signals to pass to the inferior. */ | |
831 | static void | |
832 | linux_nat_pass_signals (int numsigs, unsigned char *pass_signals) | |
833 | { | |
834 | int signo; | |
835 | ||
836 | sigemptyset (&pass_mask); | |
837 | ||
838 | for (signo = 1; signo < NSIG; signo++) | |
839 | { | |
2ea28649 | 840 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
841 | if (target_signo < numsigs && pass_signals[target_signo]) |
842 | sigaddset (&pass_mask, signo); | |
843 | } | |
844 | } | |
845 | ||
d6b0e80f AC |
846 | \f |
847 | ||
848 | /* Prototypes for local functions. */ | |
849 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 850 | static int linux_thread_alive (ptid_t ptid); |
6d8fd2b7 | 851 | static char *linux_child_pid_to_exec_file (int pid); |
710151dd | 852 | |
d6b0e80f AC |
853 | \f |
854 | /* Convert wait status STATUS to a string. Used for printing debug | |
855 | messages only. */ | |
856 | ||
857 | static char * | |
858 | status_to_str (int status) | |
859 | { | |
860 | static char buf[64]; | |
861 | ||
862 | if (WIFSTOPPED (status)) | |
206aa767 | 863 | { |
ca2163eb | 864 | if (WSTOPSIG (status) == SYSCALL_SIGTRAP) |
206aa767 DE |
865 | snprintf (buf, sizeof (buf), "%s (stopped at syscall)", |
866 | strsignal (SIGTRAP)); | |
867 | else | |
868 | snprintf (buf, sizeof (buf), "%s (stopped)", | |
869 | strsignal (WSTOPSIG (status))); | |
870 | } | |
d6b0e80f AC |
871 | else if (WIFSIGNALED (status)) |
872 | snprintf (buf, sizeof (buf), "%s (terminated)", | |
ba9b2ec3 | 873 | strsignal (WTERMSIG (status))); |
d6b0e80f AC |
874 | else |
875 | snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status)); | |
876 | ||
877 | return buf; | |
878 | } | |
879 | ||
7b50312a PA |
880 | /* Destroy and free LP. */ |
881 | ||
882 | static void | |
883 | lwp_free (struct lwp_info *lp) | |
884 | { | |
885 | xfree (lp->arch_private); | |
886 | xfree (lp); | |
887 | } | |
888 | ||
d90e17a7 PA |
889 | /* Remove all LWPs belong to PID from the lwp list. */ |
890 | ||
891 | static void | |
892 | purge_lwp_list (int pid) | |
893 | { | |
894 | struct lwp_info *lp, *lpprev, *lpnext; | |
895 | ||
896 | lpprev = NULL; | |
897 | ||
898 | for (lp = lwp_list; lp; lp = lpnext) | |
899 | { | |
900 | lpnext = lp->next; | |
901 | ||
902 | if (ptid_get_pid (lp->ptid) == pid) | |
903 | { | |
904 | if (lp == lwp_list) | |
905 | lwp_list = lp->next; | |
906 | else | |
907 | lpprev->next = lp->next; | |
908 | ||
7b50312a | 909 | lwp_free (lp); |
d90e17a7 PA |
910 | } |
911 | else | |
912 | lpprev = lp; | |
913 | } | |
914 | } | |
915 | ||
26cb8b7c PA |
916 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
917 | in the process. Return a pointer to the structure describing the | |
918 | new LWP. | |
919 | ||
920 | This differs from add_lwp in that we don't let the arch specific | |
921 | bits know about this new thread. Current clients of this callback | |
922 | take the opportunity to install watchpoints in the new thread, and | |
923 | we shouldn't do that for the first thread. If we're spawning a | |
924 | child ("run"), the thread executes the shell wrapper first, and we | |
925 | shouldn't touch it until it execs the program we want to debug. | |
926 | For "attach", it'd be okay to call the callback, but it's not | |
927 | necessary, because watchpoints can't yet have been inserted into | |
928 | the inferior. */ | |
d6b0e80f AC |
929 | |
930 | static struct lwp_info * | |
26cb8b7c | 931 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
932 | { |
933 | struct lwp_info *lp; | |
934 | ||
dfd4cc63 | 935 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
936 | |
937 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
938 | ||
939 | memset (lp, 0, sizeof (struct lwp_info)); | |
940 | ||
25289eb2 | 941 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
942 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
943 | ||
944 | lp->ptid = ptid; | |
dc146f7c | 945 | lp->core = -1; |
d6b0e80f AC |
946 | |
947 | lp->next = lwp_list; | |
948 | lwp_list = lp; | |
d6b0e80f | 949 | |
26cb8b7c PA |
950 | return lp; |
951 | } | |
952 | ||
953 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
954 | structure describing the new LWP. The LWP should already be | |
955 | stopped. */ | |
956 | ||
957 | static struct lwp_info * | |
958 | add_lwp (ptid_t ptid) | |
959 | { | |
960 | struct lwp_info *lp; | |
961 | ||
962 | lp = add_initial_lwp (ptid); | |
963 | ||
6e012a6c PA |
964 | /* Let the arch specific bits know about this new thread. Current |
965 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
966 | watchpoints in the new thread. We don't do this for the first |
967 | thread though. See add_initial_lwp. */ | |
968 | if (linux_nat_new_thread != NULL) | |
7b50312a | 969 | linux_nat_new_thread (lp); |
9f0bdab8 | 970 | |
d6b0e80f AC |
971 | return lp; |
972 | } | |
973 | ||
974 | /* Remove the LWP specified by PID from the list. */ | |
975 | ||
976 | static void | |
977 | delete_lwp (ptid_t ptid) | |
978 | { | |
979 | struct lwp_info *lp, *lpprev; | |
980 | ||
981 | lpprev = NULL; | |
982 | ||
983 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
984 | if (ptid_equal (lp->ptid, ptid)) | |
985 | break; | |
986 | ||
987 | if (!lp) | |
988 | return; | |
989 | ||
d6b0e80f AC |
990 | if (lpprev) |
991 | lpprev->next = lp->next; | |
992 | else | |
993 | lwp_list = lp->next; | |
994 | ||
7b50312a | 995 | lwp_free (lp); |
d6b0e80f AC |
996 | } |
997 | ||
998 | /* Return a pointer to the structure describing the LWP corresponding | |
999 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1000 | ||
1001 | static struct lwp_info * | |
1002 | find_lwp_pid (ptid_t ptid) | |
1003 | { | |
1004 | struct lwp_info *lp; | |
1005 | int lwp; | |
1006 | ||
dfd4cc63 LM |
1007 | if (ptid_lwp_p (ptid)) |
1008 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 1009 | else |
dfd4cc63 | 1010 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
1011 | |
1012 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 1013 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
1014 | return lp; |
1015 | ||
1016 | return NULL; | |
1017 | } | |
1018 | ||
1019 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1020 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1021 | pointer to the structure describing that LWP immediately. | |
1022 | Otherwise return NULL. */ | |
1023 | ||
1024 | struct lwp_info * | |
d90e17a7 PA |
1025 | iterate_over_lwps (ptid_t filter, |
1026 | int (*callback) (struct lwp_info *, void *), | |
1027 | void *data) | |
d6b0e80f AC |
1028 | { |
1029 | struct lwp_info *lp, *lpnext; | |
1030 | ||
1031 | for (lp = lwp_list; lp; lp = lpnext) | |
1032 | { | |
1033 | lpnext = lp->next; | |
d90e17a7 PA |
1034 | |
1035 | if (ptid_match (lp->ptid, filter)) | |
1036 | { | |
1037 | if ((*callback) (lp, data)) | |
1038 | return lp; | |
1039 | } | |
d6b0e80f AC |
1040 | } |
1041 | ||
1042 | return NULL; | |
1043 | } | |
1044 | ||
2277426b PA |
1045 | /* Update our internal state when changing from one checkpoint to |
1046 | another indicated by NEW_PTID. We can only switch single-threaded | |
1047 | applications, so we only create one new LWP, and the previous list | |
1048 | is discarded. */ | |
f973ed9c DJ |
1049 | |
1050 | void | |
1051 | linux_nat_switch_fork (ptid_t new_ptid) | |
1052 | { | |
1053 | struct lwp_info *lp; | |
1054 | ||
dfd4cc63 | 1055 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 1056 | |
f973ed9c DJ |
1057 | lp = add_lwp (new_ptid); |
1058 | lp->stopped = 1; | |
e26af52f | 1059 | |
2277426b PA |
1060 | /* This changes the thread's ptid while preserving the gdb thread |
1061 | num. Also changes the inferior pid, while preserving the | |
1062 | inferior num. */ | |
1063 | thread_change_ptid (inferior_ptid, new_ptid); | |
1064 | ||
1065 | /* We've just told GDB core that the thread changed target id, but, | |
1066 | in fact, it really is a different thread, with different register | |
1067 | contents. */ | |
1068 | registers_changed (); | |
e26af52f DJ |
1069 | } |
1070 | ||
e26af52f DJ |
1071 | /* Handle the exit of a single thread LP. */ |
1072 | ||
1073 | static void | |
1074 | exit_lwp (struct lwp_info *lp) | |
1075 | { | |
e09875d4 | 1076 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1077 | |
1078 | if (th) | |
e26af52f | 1079 | { |
17faa917 DJ |
1080 | if (print_thread_events) |
1081 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1082 | ||
4f8d22e3 | 1083 | delete_thread (lp->ptid); |
e26af52f DJ |
1084 | } |
1085 | ||
1086 | delete_lwp (lp->ptid); | |
1087 | } | |
1088 | ||
a0ef4274 DJ |
1089 | /* Wait for the LWP specified by LP, which we have just attached to. |
1090 | Returns a wait status for that LWP, to cache. */ | |
1091 | ||
1092 | static int | |
1093 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1094 | int *signalled) | |
1095 | { | |
dfd4cc63 | 1096 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
1097 | int status; |
1098 | ||
644cebc9 | 1099 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1100 | { |
1101 | if (debug_linux_nat) | |
1102 | fprintf_unfiltered (gdb_stdlog, | |
1103 | "LNPAW: Attaching to a stopped process\n"); | |
1104 | ||
1105 | /* The process is definitely stopped. It is in a job control | |
1106 | stop, unless the kernel predates the TASK_STOPPED / | |
1107 | TASK_TRACED distinction, in which case it might be in a | |
1108 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1109 | can kill it, signal it, et cetera. | |
1110 | ||
1111 | First make sure there is a pending SIGSTOP. Since we are | |
1112 | already attached, the process can not transition from stopped | |
1113 | to running without a PTRACE_CONT; so we know this signal will | |
1114 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1115 | probably already in the queue (unless this kernel is old | |
1116 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1117 | is not an RT signal, it can only be queued once. */ | |
1118 | kill_lwp (pid, SIGSTOP); | |
1119 | ||
1120 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1121 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1122 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1123 | } | |
1124 | ||
1125 | /* Make sure the initial process is stopped. The user-level threads | |
1126 | layer might want to poke around in the inferior, and that won't | |
1127 | work if things haven't stabilized yet. */ | |
1128 | new_pid = my_waitpid (pid, &status, 0); | |
1129 | if (new_pid == -1 && errno == ECHILD) | |
1130 | { | |
1131 | if (first) | |
1132 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1133 | ||
1134 | /* Try again with __WCLONE to check cloned processes. */ | |
1135 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1136 | *cloned = 1; | |
1137 | } | |
1138 | ||
dacc9cb2 PP |
1139 | gdb_assert (pid == new_pid); |
1140 | ||
1141 | if (!WIFSTOPPED (status)) | |
1142 | { | |
1143 | /* The pid we tried to attach has apparently just exited. */ | |
1144 | if (debug_linux_nat) | |
1145 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1146 | pid, status_to_str (status)); | |
1147 | return status; | |
1148 | } | |
a0ef4274 DJ |
1149 | |
1150 | if (WSTOPSIG (status) != SIGSTOP) | |
1151 | { | |
1152 | *signalled = 1; | |
1153 | if (debug_linux_nat) | |
1154 | fprintf_unfiltered (gdb_stdlog, | |
1155 | "LNPAW: Received %s after attaching\n", | |
1156 | status_to_str (status)); | |
1157 | } | |
1158 | ||
1159 | return status; | |
1160 | } | |
1161 | ||
84636d28 PA |
1162 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1163 | the new LWP could not be attached, or 1 if we're already auto | |
1164 | attached to this thread, but haven't processed the | |
1165 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1166 | its existance, without considering it an error. */ | |
d6b0e80f | 1167 | |
9ee57c33 | 1168 | int |
93815fbf | 1169 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1170 | { |
9ee57c33 | 1171 | struct lwp_info *lp; |
84636d28 | 1172 | int lwpid; |
d6b0e80f | 1173 | |
dfd4cc63 | 1174 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1175 | |
9ee57c33 | 1176 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1177 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f AC |
1178 | |
1179 | /* We assume that we're already attached to any LWP that has an id | |
1180 | equal to the overall process id, and to any LWP that is already | |
1181 | in our list of LWPs. If we're not seeing exit events from threads | |
1182 | and we've had PID wraparound since we last tried to stop all threads, | |
1183 | this assumption might be wrong; fortunately, this is very unlikely | |
1184 | to happen. */ | |
dfd4cc63 | 1185 | if (lwpid != ptid_get_pid (ptid) && lp == NULL) |
d6b0e80f | 1186 | { |
a0ef4274 | 1187 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1188 | |
84636d28 | 1189 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1190 | { |
96d7229d | 1191 | if (linux_supports_tracefork ()) |
84636d28 PA |
1192 | { |
1193 | /* If we haven't stopped all threads when we get here, | |
1194 | we may have seen a thread listed in thread_db's list, | |
1195 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1196 | that's the case, ignore this new thread, and let | |
1197 | normal event handling discover it later. */ | |
1198 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1199 | { | |
1200 | /* We've already seen this thread stop, but we | |
1201 | haven't seen the PTRACE_EVENT_CLONE extended | |
1202 | event yet. */ | |
84636d28 PA |
1203 | return 0; |
1204 | } | |
1205 | else | |
1206 | { | |
1207 | int new_pid; | |
1208 | int status; | |
1209 | ||
1210 | /* See if we've got a stop for this new child | |
1211 | pending. If so, we're already attached. */ | |
1212 | new_pid = my_waitpid (lwpid, &status, WNOHANG); | |
1213 | if (new_pid == -1 && errno == ECHILD) | |
1214 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1215 | if (new_pid != -1) | |
1216 | { | |
1217 | if (WIFSTOPPED (status)) | |
1218 | add_to_pid_list (&stopped_pids, lwpid, status); | |
84636d28 PA |
1219 | return 1; |
1220 | } | |
1221 | } | |
1222 | } | |
1223 | ||
9ee57c33 DJ |
1224 | /* If we fail to attach to the thread, issue a warning, |
1225 | but continue. One way this can happen is if thread | |
e9efe249 | 1226 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1227 | bug may place threads in the thread list and then fail |
1228 | to create them. */ | |
1229 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1230 | safe_strerror (errno)); | |
1231 | return -1; | |
1232 | } | |
1233 | ||
d6b0e80f AC |
1234 | if (debug_linux_nat) |
1235 | fprintf_unfiltered (gdb_stdlog, | |
1236 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1237 | target_pid_to_str (ptid)); | |
1238 | ||
a0ef4274 | 1239 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1240 | if (!WIFSTOPPED (status)) |
12696c10 | 1241 | return 1; |
dacc9cb2 | 1242 | |
a0ef4274 DJ |
1243 | lp = add_lwp (ptid); |
1244 | lp->stopped = 1; | |
1245 | lp->cloned = cloned; | |
1246 | lp->signalled = signalled; | |
1247 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1248 | { |
a0ef4274 DJ |
1249 | lp->resumed = 1; |
1250 | lp->status = status; | |
d6b0e80f AC |
1251 | } |
1252 | ||
dfd4cc63 | 1253 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1254 | |
1255 | if (debug_linux_nat) | |
1256 | { | |
1257 | fprintf_unfiltered (gdb_stdlog, | |
1258 | "LLAL: waitpid %s received %s\n", | |
1259 | target_pid_to_str (ptid), | |
1260 | status_to_str (status)); | |
1261 | } | |
1262 | } | |
1263 | else | |
1264 | { | |
1265 | /* We assume that the LWP representing the original process is | |
1266 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1267 | that the GNU/linux ptrace layer uses to keep track of |
1268 | threads. Note that this won't have already been done since | |
1269 | the main thread will have, we assume, been stopped by an | |
1270 | attach from a different layer. */ | |
9ee57c33 DJ |
1271 | if (lp == NULL) |
1272 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1273 | lp->stopped = 1; |
1274 | } | |
9ee57c33 | 1275 | |
25289eb2 | 1276 | lp->last_resume_kind = resume_stop; |
9ee57c33 | 1277 | return 0; |
d6b0e80f AC |
1278 | } |
1279 | ||
b84876c2 | 1280 | static void |
136d6dae VP |
1281 | linux_nat_create_inferior (struct target_ops *ops, |
1282 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1283 | int from_tty) |
1284 | { | |
10568435 JK |
1285 | #ifdef HAVE_PERSONALITY |
1286 | int personality_orig = 0, personality_set = 0; | |
1287 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1288 | |
1289 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1290 | we have to mask the async mode. */ | |
1291 | ||
10568435 JK |
1292 | #ifdef HAVE_PERSONALITY |
1293 | if (disable_randomization) | |
1294 | { | |
1295 | errno = 0; | |
1296 | personality_orig = personality (0xffffffff); | |
1297 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1298 | { | |
1299 | personality_set = 1; | |
1300 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1301 | } | |
1302 | if (errno != 0 || (personality_set | |
1303 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1304 | warning (_("Error disabling address space randomization: %s"), | |
1305 | safe_strerror (errno)); | |
1306 | } | |
1307 | #endif /* HAVE_PERSONALITY */ | |
1308 | ||
2455069d UW |
1309 | /* Make sure we report all signals during startup. */ |
1310 | linux_nat_pass_signals (0, NULL); | |
1311 | ||
136d6dae | 1312 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1313 | |
10568435 JK |
1314 | #ifdef HAVE_PERSONALITY |
1315 | if (personality_set) | |
1316 | { | |
1317 | errno = 0; | |
1318 | personality (personality_orig); | |
1319 | if (errno != 0) | |
1320 | warning (_("Error restoring address space randomization: %s"), | |
1321 | safe_strerror (errno)); | |
1322 | } | |
1323 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1324 | } |
1325 | ||
d6b0e80f | 1326 | static void |
136d6dae | 1327 | linux_nat_attach (struct target_ops *ops, char *args, int from_tty) |
d6b0e80f AC |
1328 | { |
1329 | struct lwp_info *lp; | |
d6b0e80f | 1330 | int status; |
af990527 | 1331 | ptid_t ptid; |
87b0bb13 | 1332 | volatile struct gdb_exception ex; |
d6b0e80f | 1333 | |
2455069d UW |
1334 | /* Make sure we report all signals during attach. */ |
1335 | linux_nat_pass_signals (0, NULL); | |
1336 | ||
87b0bb13 JK |
1337 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
1338 | { | |
1339 | linux_ops->to_attach (ops, args, from_tty); | |
1340 | } | |
1341 | if (ex.reason < 0) | |
1342 | { | |
1343 | pid_t pid = parse_pid_to_attach (args); | |
1344 | struct buffer buffer; | |
1345 | char *message, *buffer_s; | |
1346 | ||
1347 | message = xstrdup (ex.message); | |
1348 | make_cleanup (xfree, message); | |
1349 | ||
1350 | buffer_init (&buffer); | |
1351 | linux_ptrace_attach_warnings (pid, &buffer); | |
1352 | ||
1353 | buffer_grow_str0 (&buffer, ""); | |
1354 | buffer_s = buffer_finish (&buffer); | |
1355 | make_cleanup (xfree, buffer_s); | |
1356 | ||
1357 | throw_error (ex.error, "%s%s", buffer_s, message); | |
1358 | } | |
d6b0e80f | 1359 | |
af990527 PA |
1360 | /* The ptrace base target adds the main thread with (pid,0,0) |
1361 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1362 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1363 | ptid_get_pid (inferior_ptid), | |
1364 | 0); | |
af990527 PA |
1365 | thread_change_ptid (inferior_ptid, ptid); |
1366 | ||
9f0bdab8 | 1367 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1368 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1369 | |
1370 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1371 | &lp->signalled); | |
dacc9cb2 PP |
1372 | if (!WIFSTOPPED (status)) |
1373 | { | |
1374 | if (WIFEXITED (status)) | |
1375 | { | |
1376 | int exit_code = WEXITSTATUS (status); | |
1377 | ||
1378 | target_terminal_ours (); | |
1379 | target_mourn_inferior (); | |
1380 | if (exit_code == 0) | |
1381 | error (_("Unable to attach: program exited normally.")); | |
1382 | else | |
1383 | error (_("Unable to attach: program exited with code %d."), | |
1384 | exit_code); | |
1385 | } | |
1386 | else if (WIFSIGNALED (status)) | |
1387 | { | |
2ea28649 | 1388 | enum gdb_signal signo; |
dacc9cb2 PP |
1389 | |
1390 | target_terminal_ours (); | |
1391 | target_mourn_inferior (); | |
1392 | ||
2ea28649 | 1393 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1394 | error (_("Unable to attach: program terminated with signal " |
1395 | "%s, %s."), | |
2ea28649 PA |
1396 | gdb_signal_to_name (signo), |
1397 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1398 | } |
1399 | ||
1400 | internal_error (__FILE__, __LINE__, | |
1401 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1402 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1403 | } |
1404 | ||
a0ef4274 | 1405 | lp->stopped = 1; |
9f0bdab8 | 1406 | |
a0ef4274 | 1407 | /* Save the wait status to report later. */ |
d6b0e80f | 1408 | lp->resumed = 1; |
a0ef4274 DJ |
1409 | if (debug_linux_nat) |
1410 | fprintf_unfiltered (gdb_stdlog, | |
1411 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1412 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1413 | |
7feb7d06 PA |
1414 | lp->status = status; |
1415 | ||
1416 | if (target_can_async_p ()) | |
1417 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1418 | } |
1419 | ||
a0ef4274 DJ |
1420 | /* Get pending status of LP. */ |
1421 | static int | |
1422 | get_pending_status (struct lwp_info *lp, int *status) | |
1423 | { | |
a493e3e2 | 1424 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1425 | |
1426 | /* If we paused threads momentarily, we may have stored pending | |
1427 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1428 | and GDB core hasn't seen any signal for those threads. | |
1429 | Otherwise, the last signal reported to the core is found in the | |
1430 | thread object's stop_signal. | |
1431 | ||
1432 | There's a corner case that isn't handled here at present. Only | |
1433 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1434 | stop_signal make sense as a real signal to pass to the inferior. | |
1435 | Some catchpoint related events, like | |
1436 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1437 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1438 | those traps are debug API (ptrace in our case) related and |
1439 | induced; the inferior wouldn't see them if it wasn't being | |
1440 | traced. Hence, we should never pass them to the inferior, even | |
1441 | when set to pass state. Since this corner case isn't handled by | |
1442 | infrun.c when proceeding with a signal, for consistency, neither | |
1443 | do we handle it here (or elsewhere in the file we check for | |
1444 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1445 | this is really a corner case. */ | |
1446 | ||
1447 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1448 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1449 | else if (lp->status) |
2ea28649 | 1450 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1451 | else if (non_stop && !is_executing (lp->ptid)) |
1452 | { | |
1453 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1454 | |
16c381f0 | 1455 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1456 | } |
1457 | else if (!non_stop) | |
a0ef4274 | 1458 | { |
ca2163eb PA |
1459 | struct target_waitstatus last; |
1460 | ptid_t last_ptid; | |
4c28f408 | 1461 | |
ca2163eb | 1462 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1463 | |
dfd4cc63 | 1464 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1465 | { |
e09875d4 | 1466 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1467 | |
16c381f0 | 1468 | signo = tp->suspend.stop_signal; |
4c28f408 | 1469 | } |
ca2163eb | 1470 | } |
4c28f408 | 1471 | |
ca2163eb | 1472 | *status = 0; |
4c28f408 | 1473 | |
a493e3e2 | 1474 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1475 | { |
1476 | if (debug_linux_nat) | |
1477 | fprintf_unfiltered (gdb_stdlog, | |
1478 | "GPT: lwp %s has no pending signal\n", | |
1479 | target_pid_to_str (lp->ptid)); | |
1480 | } | |
1481 | else if (!signal_pass_state (signo)) | |
1482 | { | |
1483 | if (debug_linux_nat) | |
3e43a32a MS |
1484 | fprintf_unfiltered (gdb_stdlog, |
1485 | "GPT: lwp %s had signal %s, " | |
1486 | "but it is in no pass state\n", | |
ca2163eb | 1487 | target_pid_to_str (lp->ptid), |
2ea28649 | 1488 | gdb_signal_to_string (signo)); |
a0ef4274 | 1489 | } |
a0ef4274 | 1490 | else |
4c28f408 | 1491 | { |
2ea28649 | 1492 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1493 | |
1494 | if (debug_linux_nat) | |
1495 | fprintf_unfiltered (gdb_stdlog, | |
1496 | "GPT: lwp %s has pending signal %s\n", | |
1497 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1498 | gdb_signal_to_string (signo)); |
4c28f408 | 1499 | } |
a0ef4274 DJ |
1500 | |
1501 | return 0; | |
1502 | } | |
1503 | ||
d6b0e80f AC |
1504 | static int |
1505 | detach_callback (struct lwp_info *lp, void *data) | |
1506 | { | |
1507 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1508 | ||
1509 | if (debug_linux_nat && lp->status) | |
1510 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1511 | strsignal (WSTOPSIG (lp->status)), | |
1512 | target_pid_to_str (lp->ptid)); | |
1513 | ||
a0ef4274 DJ |
1514 | /* If there is a pending SIGSTOP, get rid of it. */ |
1515 | if (lp->signalled) | |
d6b0e80f | 1516 | { |
d6b0e80f AC |
1517 | if (debug_linux_nat) |
1518 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1519 | "DC: Sending SIGCONT to %s\n", |
1520 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1521 | |
dfd4cc63 | 1522 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1523 | lp->signalled = 0; |
d6b0e80f AC |
1524 | } |
1525 | ||
1526 | /* We don't actually detach from the LWP that has an id equal to the | |
1527 | overall process id just yet. */ | |
dfd4cc63 | 1528 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1529 | { |
a0ef4274 DJ |
1530 | int status = 0; |
1531 | ||
1532 | /* Pass on any pending signal for this LWP. */ | |
1533 | get_pending_status (lp, &status); | |
1534 | ||
7b50312a PA |
1535 | if (linux_nat_prepare_to_resume != NULL) |
1536 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1537 | errno = 0; |
dfd4cc63 | 1538 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1539 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1540 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1541 | safe_strerror (errno)); |
1542 | ||
1543 | if (debug_linux_nat) | |
1544 | fprintf_unfiltered (gdb_stdlog, | |
1545 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1546 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1547 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1548 | |
1549 | delete_lwp (lp->ptid); | |
1550 | } | |
1551 | ||
1552 | return 0; | |
1553 | } | |
1554 | ||
1555 | static void | |
52554a0e | 1556 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1557 | { |
b84876c2 | 1558 | int pid; |
a0ef4274 | 1559 | int status; |
d90e17a7 PA |
1560 | struct lwp_info *main_lwp; |
1561 | ||
dfd4cc63 | 1562 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1563 | |
ae5e0686 MK |
1564 | /* Don't unregister from the event loop, as there may be other |
1565 | inferiors running. */ | |
b84876c2 | 1566 | |
4c28f408 PA |
1567 | /* Stop all threads before detaching. ptrace requires that the |
1568 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1569 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1570 | /* ... and wait until all of them have reported back that |
1571 | they're no longer running. */ | |
d90e17a7 | 1572 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1573 | |
d90e17a7 | 1574 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1575 | |
1576 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1577 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1578 | |
1579 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1580 | |
a0ef4274 DJ |
1581 | /* Pass on any pending signal for the last LWP. */ |
1582 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1583 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1584 | && WIFSTOPPED (status)) |
1585 | { | |
52554a0e TT |
1586 | char *tem; |
1587 | ||
a0ef4274 DJ |
1588 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1589 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1590 | tem = alloca (8); |
cde33bf1 | 1591 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1592 | args = tem; |
ddabfc73 TT |
1593 | if (debug_linux_nat) |
1594 | fprintf_unfiltered (gdb_stdlog, | |
1595 | "LND: Sending signal %s to %s\n", | |
1596 | args, | |
1597 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1598 | } |
1599 | ||
7b50312a PA |
1600 | if (linux_nat_prepare_to_resume != NULL) |
1601 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1602 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1603 | |
7a7d3353 PA |
1604 | if (forks_exist_p ()) |
1605 | { | |
1606 | /* Multi-fork case. The current inferior_ptid is being detached | |
1607 | from, but there are other viable forks to debug. Detach from | |
1608 | the current fork, and context-switch to the first | |
1609 | available. */ | |
1610 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1611 | } |
1612 | else | |
1613 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1614 | } |
1615 | ||
1616 | /* Resume LP. */ | |
1617 | ||
25289eb2 | 1618 | static void |
e5ef252a | 1619 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1620 | { |
25289eb2 | 1621 | if (lp->stopped) |
6c95b8df | 1622 | { |
dfd4cc63 | 1623 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
25289eb2 PA |
1624 | |
1625 | if (inf->vfork_child != NULL) | |
1626 | { | |
1627 | if (debug_linux_nat) | |
1628 | fprintf_unfiltered (gdb_stdlog, | |
1629 | "RC: Not resuming %s (vfork parent)\n", | |
1630 | target_pid_to_str (lp->ptid)); | |
1631 | } | |
1632 | else if (lp->status == 0 | |
1633 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
1634 | { | |
1635 | if (debug_linux_nat) | |
1636 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1637 | "RC: Resuming sibling %s, %s, %s\n", |
1638 | target_pid_to_str (lp->ptid), | |
1639 | (signo != GDB_SIGNAL_0 | |
1640 | ? strsignal (gdb_signal_to_host (signo)) | |
1641 | : "0"), | |
1642 | step ? "step" : "resume"); | |
25289eb2 | 1643 | |
7b50312a PA |
1644 | if (linux_nat_prepare_to_resume != NULL) |
1645 | linux_nat_prepare_to_resume (lp); | |
25289eb2 | 1646 | linux_ops->to_resume (linux_ops, |
dfd4cc63 | 1647 | pid_to_ptid (ptid_get_lwp (lp->ptid)), |
e5ef252a | 1648 | step, signo); |
25289eb2 PA |
1649 | lp->stopped = 0; |
1650 | lp->step = step; | |
25289eb2 PA |
1651 | lp->stopped_by_watchpoint = 0; |
1652 | } | |
1653 | else | |
1654 | { | |
1655 | if (debug_linux_nat) | |
1656 | fprintf_unfiltered (gdb_stdlog, | |
1657 | "RC: Not resuming sibling %s (has pending)\n", | |
1658 | target_pid_to_str (lp->ptid)); | |
1659 | } | |
6c95b8df | 1660 | } |
25289eb2 | 1661 | else |
d6b0e80f | 1662 | { |
d90e17a7 PA |
1663 | if (debug_linux_nat) |
1664 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1665 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1666 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1667 | } |
25289eb2 | 1668 | } |
d6b0e80f | 1669 | |
e5ef252a PA |
1670 | /* Resume LWP, with the last stop signal, if it is in pass state. */ |
1671 | ||
25289eb2 | 1672 | static int |
e5ef252a | 1673 | linux_nat_resume_callback (struct lwp_info *lp, void *data) |
25289eb2 | 1674 | { |
e5ef252a PA |
1675 | enum gdb_signal signo = GDB_SIGNAL_0; |
1676 | ||
1677 | if (lp->stopped) | |
1678 | { | |
1679 | struct thread_info *thread; | |
1680 | ||
1681 | thread = find_thread_ptid (lp->ptid); | |
1682 | if (thread != NULL) | |
1683 | { | |
1684 | if (signal_pass_state (thread->suspend.stop_signal)) | |
1685 | signo = thread->suspend.stop_signal; | |
1686 | thread->suspend.stop_signal = GDB_SIGNAL_0; | |
1687 | } | |
1688 | } | |
1689 | ||
1690 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1691 | return 0; |
1692 | } | |
1693 | ||
1694 | static int | |
1695 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1696 | { | |
1697 | lp->resumed = 0; | |
25289eb2 | 1698 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1699 | return 0; |
1700 | } | |
1701 | ||
1702 | static int | |
1703 | resume_set_callback (struct lwp_info *lp, void *data) | |
1704 | { | |
1705 | lp->resumed = 1; | |
25289eb2 | 1706 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1707 | return 0; |
1708 | } | |
1709 | ||
1710 | static void | |
28439f5e | 1711 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1712 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1713 | { |
1714 | struct lwp_info *lp; | |
d90e17a7 | 1715 | int resume_many; |
d6b0e80f | 1716 | |
76f50ad1 DJ |
1717 | if (debug_linux_nat) |
1718 | fprintf_unfiltered (gdb_stdlog, | |
1719 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1720 | step ? "step" : "resume", | |
1721 | target_pid_to_str (ptid), | |
a493e3e2 | 1722 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1723 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1724 | target_pid_to_str (inferior_ptid)); |
1725 | ||
d6b0e80f | 1726 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1727 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1728 | || ptid_is_pid (ptid)); | |
4c28f408 | 1729 | |
e3e9f5a2 PA |
1730 | /* Mark the lwps we're resuming as resumed. */ |
1731 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1732 | |
d90e17a7 PA |
1733 | /* See if it's the current inferior that should be handled |
1734 | specially. */ | |
1735 | if (resume_many) | |
1736 | lp = find_lwp_pid (inferior_ptid); | |
1737 | else | |
1738 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1739 | gdb_assert (lp != NULL); |
d6b0e80f | 1740 | |
9f0bdab8 DJ |
1741 | /* Remember if we're stepping. */ |
1742 | lp->step = step; | |
25289eb2 | 1743 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1744 | |
9f0bdab8 DJ |
1745 | /* If we have a pending wait status for this thread, there is no |
1746 | point in resuming the process. But first make sure that | |
1747 | linux_nat_wait won't preemptively handle the event - we | |
1748 | should never take this short-circuit if we are going to | |
1749 | leave LP running, since we have skipped resuming all the | |
1750 | other threads. This bit of code needs to be synchronized | |
1751 | with linux_nat_wait. */ | |
76f50ad1 | 1752 | |
9f0bdab8 DJ |
1753 | if (lp->status && WIFSTOPPED (lp->status)) |
1754 | { | |
2455069d UW |
1755 | if (!lp->step |
1756 | && WSTOPSIG (lp->status) | |
1757 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1758 | { |
9f0bdab8 DJ |
1759 | if (debug_linux_nat) |
1760 | fprintf_unfiltered (gdb_stdlog, | |
1761 | "LLR: Not short circuiting for ignored " | |
1762 | "status 0x%x\n", lp->status); | |
1763 | ||
d6b0e80f AC |
1764 | /* FIXME: What should we do if we are supposed to continue |
1765 | this thread with a signal? */ | |
a493e3e2 | 1766 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1767 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1768 | lp->status = 0; |
1769 | } | |
1770 | } | |
76f50ad1 | 1771 | |
6c95b8df | 1772 | if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) |
9f0bdab8 DJ |
1773 | { |
1774 | /* FIXME: What should we do if we are supposed to continue | |
1775 | this thread with a signal? */ | |
a493e3e2 | 1776 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1777 | |
9f0bdab8 DJ |
1778 | if (debug_linux_nat) |
1779 | fprintf_unfiltered (gdb_stdlog, | |
1780 | "LLR: Short circuiting for status 0x%x\n", | |
1781 | lp->status); | |
d6b0e80f | 1782 | |
7feb7d06 PA |
1783 | if (target_can_async_p ()) |
1784 | { | |
1785 | target_async (inferior_event_handler, 0); | |
1786 | /* Tell the event loop we have something to process. */ | |
1787 | async_file_mark (); | |
1788 | } | |
9f0bdab8 | 1789 | return; |
d6b0e80f AC |
1790 | } |
1791 | ||
9f0bdab8 | 1792 | /* Mark LWP as not stopped to prevent it from being continued by |
e5ef252a | 1793 | linux_nat_resume_callback. */ |
9f0bdab8 DJ |
1794 | lp->stopped = 0; |
1795 | ||
d90e17a7 | 1796 | if (resume_many) |
e5ef252a | 1797 | iterate_over_lwps (ptid, linux_nat_resume_callback, NULL); |
d90e17a7 PA |
1798 | |
1799 | /* Convert to something the lower layer understands. */ | |
dfd4cc63 | 1800 | ptid = pid_to_ptid (ptid_get_lwp (lp->ptid)); |
d6b0e80f | 1801 | |
7b50312a PA |
1802 | if (linux_nat_prepare_to_resume != NULL) |
1803 | linux_nat_prepare_to_resume (lp); | |
28439f5e | 1804 | linux_ops->to_resume (linux_ops, ptid, step, signo); |
ebec9a0f | 1805 | lp->stopped_by_watchpoint = 0; |
9f0bdab8 | 1806 | |
d6b0e80f AC |
1807 | if (debug_linux_nat) |
1808 | fprintf_unfiltered (gdb_stdlog, | |
1809 | "LLR: %s %s, %s (resume event thread)\n", | |
1810 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1811 | target_pid_to_str (ptid), | |
a493e3e2 | 1812 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1813 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1814 | |
1815 | if (target_can_async_p ()) | |
8ea051c5 | 1816 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1817 | } |
1818 | ||
c5f62d5f | 1819 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1820 | |
1821 | static int | |
1822 | kill_lwp (int lwpid, int signo) | |
1823 | { | |
c5f62d5f DE |
1824 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1825 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1826 | |
1827 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1828 | { |
1829 | static int tkill_failed; | |
1830 | ||
1831 | if (!tkill_failed) | |
1832 | { | |
1833 | int ret; | |
1834 | ||
1835 | errno = 0; | |
1836 | ret = syscall (__NR_tkill, lwpid, signo); | |
1837 | if (errno != ENOSYS) | |
1838 | return ret; | |
1839 | tkill_failed = 1; | |
1840 | } | |
1841 | } | |
d6b0e80f AC |
1842 | #endif |
1843 | ||
1844 | return kill (lwpid, signo); | |
1845 | } | |
1846 | ||
ca2163eb PA |
1847 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1848 | event, check if the core is interested in it: if not, ignore the | |
1849 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1850 | syscall entry/exit status, since the ptrace event itself doesn't | |
1851 | indicate it, and report the trap to higher layers. */ | |
1852 | ||
1853 | static int | |
1854 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1855 | { | |
1856 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1857 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1858 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1859 | ||
1860 | if (stopping) | |
1861 | { | |
1862 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1863 | makes it so that the LWP reports an immediate syscall return, | |
1864 | followed by the SIGSTOP. Skip seeing that "return" using | |
1865 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1866 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1867 | entry event. If we didn't do this (and returned 0), we'd | |
1868 | leave a syscall entry pending, and our caller, by using | |
1869 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1870 | itself. Later, when the user re-resumes this LWP, we'd see | |
1871 | another syscall entry event and we'd mistake it for a return. | |
1872 | ||
1873 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1874 | (leaving immediately with LWP->signalled set, without issuing | |
1875 | a PTRACE_CONT), it would still be problematic to leave this | |
1876 | syscall enter pending, as later when the thread is resumed, | |
1877 | it would then see the same syscall exit mentioned above, | |
1878 | followed by the delayed SIGSTOP, while the syscall didn't | |
1879 | actually get to execute. It seems it would be even more | |
1880 | confusing to the user. */ | |
1881 | ||
1882 | if (debug_linux_nat) | |
1883 | fprintf_unfiltered (gdb_stdlog, | |
1884 | "LHST: ignoring syscall %d " | |
1885 | "for LWP %ld (stopping threads), " | |
1886 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1887 | syscall_number, | |
dfd4cc63 | 1888 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1889 | |
1890 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1891 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
ca2163eb PA |
1892 | return 1; |
1893 | } | |
1894 | ||
1895 | if (catch_syscall_enabled ()) | |
1896 | { | |
1897 | /* Always update the entry/return state, even if this particular | |
1898 | syscall isn't interesting to the core now. In async mode, | |
1899 | the user could install a new catchpoint for this syscall | |
1900 | between syscall enter/return, and we'll need to know to | |
1901 | report a syscall return if that happens. */ | |
1902 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1903 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1904 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1905 | ||
1906 | if (catching_syscall_number (syscall_number)) | |
1907 | { | |
1908 | /* Alright, an event to report. */ | |
1909 | ourstatus->kind = lp->syscall_state; | |
1910 | ourstatus->value.syscall_number = syscall_number; | |
1911 | ||
1912 | if (debug_linux_nat) | |
1913 | fprintf_unfiltered (gdb_stdlog, | |
1914 | "LHST: stopping for %s of syscall %d" | |
1915 | " for LWP %ld\n", | |
3e43a32a MS |
1916 | lp->syscall_state |
1917 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1918 | ? "entry" : "return", |
1919 | syscall_number, | |
dfd4cc63 | 1920 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1921 | return 0; |
1922 | } | |
1923 | ||
1924 | if (debug_linux_nat) | |
1925 | fprintf_unfiltered (gdb_stdlog, | |
1926 | "LHST: ignoring %s of syscall %d " | |
1927 | "for LWP %ld\n", | |
1928 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1929 | ? "entry" : "return", | |
1930 | syscall_number, | |
dfd4cc63 | 1931 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1932 | } |
1933 | else | |
1934 | { | |
1935 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1936 | before on this LWP, it could happen that the user removes all | |
1937 | syscall catchpoints before we get to process this event. | |
1938 | There are two noteworthy issues here: | |
1939 | ||
1940 | - When stopped at a syscall entry event, resuming with | |
1941 | PT_STEP still resumes executing the syscall and reports a | |
1942 | syscall return. | |
1943 | ||
1944 | - Only PT_SYSCALL catches syscall enters. If we last | |
1945 | single-stepped this thread, then this event can't be a | |
1946 | syscall enter. If we last single-stepped this thread, this | |
1947 | has to be a syscall exit. | |
1948 | ||
1949 | The points above mean that the next resume, be it PT_STEP or | |
1950 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1951 | if (debug_linux_nat) | |
1952 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1953 | "LHST: caught syscall event " |
1954 | "with no syscall catchpoints." | |
ca2163eb PA |
1955 | " %d for LWP %ld, ignoring\n", |
1956 | syscall_number, | |
dfd4cc63 | 1957 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1958 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1959 | } | |
1960 | ||
1961 | /* The core isn't interested in this event. For efficiency, avoid | |
1962 | stopping all threads only to have the core resume them all again. | |
1963 | Since we're not stopping threads, if we're still syscall tracing | |
1964 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1965 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1966 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1967 | ||
1968 | /* Note that gdbarch_get_syscall_number may access registers, hence | |
1969 | fill a regcache. */ | |
1970 | registers_changed (); | |
7b50312a PA |
1971 | if (linux_nat_prepare_to_resume != NULL) |
1972 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 1973 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 1974 | lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1975 | return 1; |
1976 | } | |
1977 | ||
3d799a95 DJ |
1978 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1979 | event, we need to add the new LWP to our list (and not report the | |
1980 | trap to higher layers). This function returns non-zero if the | |
1981 | event should be ignored and we should wait again. If STOPPING is | |
1982 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1983 | |
1984 | static int | |
3d799a95 DJ |
1985 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1986 | int stopping) | |
d6b0e80f | 1987 | { |
dfd4cc63 | 1988 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1989 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
3d799a95 | 1990 | int event = status >> 16; |
d6b0e80f | 1991 | |
3d799a95 DJ |
1992 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1993 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1994 | { |
3d799a95 DJ |
1995 | unsigned long new_pid; |
1996 | int ret; | |
1997 | ||
1998 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1999 | |
3d799a95 DJ |
2000 | /* If we haven't already seen the new PID stop, wait for it now. */ |
2001 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2002 | { | |
2003 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2004 | hits the SIGSTOP, but we're already attached. */ | |
2005 | ret = my_waitpid (new_pid, &status, | |
2006 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2007 | if (ret == -1) | |
2008 | perror_with_name (_("waiting for new child")); | |
2009 | else if (ret != new_pid) | |
2010 | internal_error (__FILE__, __LINE__, | |
2011 | _("wait returned unexpected PID %d"), ret); | |
2012 | else if (!WIFSTOPPED (status)) | |
2013 | internal_error (__FILE__, __LINE__, | |
2014 | _("wait returned unexpected status 0x%x"), status); | |
2015 | } | |
2016 | ||
3a3e9ee3 | 2017 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2018 | |
26cb8b7c PA |
2019 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2020 | { | |
2021 | /* The arch-specific native code may need to know about new | |
2022 | forks even if those end up never mapped to an | |
2023 | inferior. */ | |
2024 | if (linux_nat_new_fork != NULL) | |
2025 | linux_nat_new_fork (lp, new_pid); | |
2026 | } | |
2027 | ||
2277426b | 2028 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2029 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2030 | { |
2277426b PA |
2031 | /* Handle checkpointing by linux-fork.c here as a special |
2032 | case. We don't want the follow-fork-mode or 'catch fork' | |
2033 | to interfere with this. */ | |
2034 | ||
2035 | /* This won't actually modify the breakpoint list, but will | |
2036 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2037 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2038 | |
2039 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2040 | if (!find_fork_pid (new_pid)) |
2041 | add_fork (new_pid); | |
2277426b PA |
2042 | |
2043 | /* Report as spurious, so that infrun doesn't want to follow | |
2044 | this fork. We're actually doing an infcall in | |
2045 | linux-fork.c. */ | |
2046 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2047 | |
2048 | /* Report the stop to the core. */ | |
2049 | return 0; | |
2050 | } | |
2051 | ||
3d799a95 DJ |
2052 | if (event == PTRACE_EVENT_FORK) |
2053 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2054 | else if (event == PTRACE_EVENT_VFORK) | |
2055 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2056 | else |
3d799a95 | 2057 | { |
78768c4a JK |
2058 | struct lwp_info *new_lp; |
2059 | ||
3d799a95 | 2060 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2061 | |
3c4d7e12 PA |
2062 | if (debug_linux_nat) |
2063 | fprintf_unfiltered (gdb_stdlog, | |
2064 | "LHEW: Got clone event " | |
2065 | "from LWP %d, new child is LWP %ld\n", | |
2066 | pid, new_pid); | |
2067 | ||
dfd4cc63 | 2068 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2069 | new_lp->cloned = 1; |
4c28f408 | 2070 | new_lp->stopped = 1; |
d6b0e80f | 2071 | |
3d799a95 DJ |
2072 | if (WSTOPSIG (status) != SIGSTOP) |
2073 | { | |
2074 | /* This can happen if someone starts sending signals to | |
2075 | the new thread before it gets a chance to run, which | |
2076 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2077 | This is an unlikely case, and harder to handle for | |
2078 | fork / vfork than for clone, so we do not try - but | |
2079 | we handle it for clone events here. We'll send | |
2080 | the other signal on to the thread below. */ | |
2081 | ||
2082 | new_lp->signalled = 1; | |
2083 | } | |
2084 | else | |
79395f92 PA |
2085 | { |
2086 | struct thread_info *tp; | |
2087 | ||
2088 | /* When we stop for an event in some other thread, and | |
2089 | pull the thread list just as this thread has cloned, | |
2090 | we'll have seen the new thread in the thread_db list | |
2091 | before handling the CLONE event (glibc's | |
2092 | pthread_create adds the new thread to the thread list | |
2093 | before clone'ing, and has the kernel fill in the | |
2094 | thread's tid on the clone call with | |
2095 | CLONE_PARENT_SETTID). If that happened, and the core | |
2096 | had requested the new thread to stop, we'll have | |
2097 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2098 | RT signal, it can only be queued once. We need to be | |
2099 | careful to not resume the LWP if we wanted it to | |
2100 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2101 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2102 | tp = find_thread_ptid (new_lp->ptid); |
2103 | if (tp != NULL && tp->stop_requested) | |
2104 | new_lp->last_resume_kind = resume_stop; | |
2105 | else | |
2106 | status = 0; | |
2107 | } | |
d6b0e80f | 2108 | |
4c28f408 | 2109 | if (non_stop) |
3d799a95 | 2110 | { |
4c28f408 PA |
2111 | /* Add the new thread to GDB's lists as soon as possible |
2112 | so that: | |
2113 | ||
2114 | 1) the frontend doesn't have to wait for a stop to | |
2115 | display them, and, | |
2116 | ||
2117 | 2) we tag it with the correct running state. */ | |
2118 | ||
2119 | /* If the thread_db layer is active, let it know about | |
2120 | this new thread, and add it to GDB's list. */ | |
2121 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
2122 | { | |
2123 | /* We're not using thread_db. Add it to GDB's | |
2124 | list. */ | |
dfd4cc63 | 2125 | target_post_attach (ptid_get_lwp (new_lp->ptid)); |
4c28f408 PA |
2126 | add_thread (new_lp->ptid); |
2127 | } | |
2128 | ||
2129 | if (!stopping) | |
2130 | { | |
2131 | set_running (new_lp->ptid, 1); | |
2132 | set_executing (new_lp->ptid, 1); | |
e21ffe51 PA |
2133 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced |
2134 | resume_stop. */ | |
2135 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2136 | } |
2137 | } | |
2138 | ||
79395f92 PA |
2139 | if (status != 0) |
2140 | { | |
2141 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2142 | gdb_assert (new_lp->status == 0); | |
2143 | ||
2144 | /* Save the wait status to report later. */ | |
2145 | if (debug_linux_nat) | |
2146 | fprintf_unfiltered (gdb_stdlog, | |
2147 | "LHEW: waitpid of new LWP %ld, " | |
2148 | "saving status %s\n", | |
dfd4cc63 | 2149 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2150 | status_to_str (status)); |
2151 | new_lp->status = status; | |
2152 | } | |
2153 | ||
ca2163eb PA |
2154 | /* Note the need to use the low target ops to resume, to |
2155 | handle resuming with PT_SYSCALL if we have syscall | |
2156 | catchpoints. */ | |
4c28f408 PA |
2157 | if (!stopping) |
2158 | { | |
3d799a95 | 2159 | new_lp->resumed = 1; |
ca2163eb | 2160 | |
79395f92 | 2161 | if (status == 0) |
ad34eb2f | 2162 | { |
e21ffe51 | 2163 | gdb_assert (new_lp->last_resume_kind == resume_continue); |
ad34eb2f JK |
2164 | if (debug_linux_nat) |
2165 | fprintf_unfiltered (gdb_stdlog, | |
79395f92 | 2166 | "LHEW: resuming new LWP %ld\n", |
dfd4cc63 | 2167 | ptid_get_lwp (new_lp->ptid)); |
7b50312a PA |
2168 | if (linux_nat_prepare_to_resume != NULL) |
2169 | linux_nat_prepare_to_resume (new_lp); | |
79395f92 | 2170 | linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid), |
a493e3e2 | 2171 | 0, GDB_SIGNAL_0); |
79395f92 | 2172 | new_lp->stopped = 0; |
ad34eb2f JK |
2173 | } |
2174 | } | |
d6b0e80f | 2175 | |
3d799a95 DJ |
2176 | if (debug_linux_nat) |
2177 | fprintf_unfiltered (gdb_stdlog, | |
3c4d7e12 | 2178 | "LHEW: resuming parent LWP %d\n", pid); |
7b50312a PA |
2179 | if (linux_nat_prepare_to_resume != NULL) |
2180 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
2181 | linux_ops->to_resume (linux_ops, |
2182 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
a493e3e2 | 2183 | 0, GDB_SIGNAL_0); |
3d799a95 DJ |
2184 | |
2185 | return 1; | |
2186 | } | |
2187 | ||
2188 | return 0; | |
d6b0e80f AC |
2189 | } |
2190 | ||
3d799a95 DJ |
2191 | if (event == PTRACE_EVENT_EXEC) |
2192 | { | |
a75724bc PA |
2193 | if (debug_linux_nat) |
2194 | fprintf_unfiltered (gdb_stdlog, | |
2195 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2196 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2197 | |
3d799a95 DJ |
2198 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2199 | ourstatus->value.execd_pathname | |
6d8fd2b7 | 2200 | = xstrdup (linux_child_pid_to_exec_file (pid)); |
3d799a95 | 2201 | |
6c95b8df PA |
2202 | return 0; |
2203 | } | |
2204 | ||
2205 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2206 | { | |
2207 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2208 | { |
6c95b8df | 2209 | if (debug_linux_nat) |
3e43a32a MS |
2210 | fprintf_unfiltered (gdb_stdlog, |
2211 | "LHEW: Got expected PTRACE_EVENT_" | |
2212 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2213 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2214 | |
6c95b8df PA |
2215 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2216 | return 0; | |
3d799a95 DJ |
2217 | } |
2218 | ||
6c95b8df | 2219 | if (debug_linux_nat) |
3e43a32a MS |
2220 | fprintf_unfiltered (gdb_stdlog, |
2221 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
2222 | "from LWP %ld: resuming\n", | |
dfd4cc63 LM |
2223 | ptid_get_lwp (lp->ptid)); |
2224 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); | |
6c95b8df | 2225 | return 1; |
3d799a95 DJ |
2226 | } |
2227 | ||
2228 | internal_error (__FILE__, __LINE__, | |
2229 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2230 | } |
2231 | ||
2232 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2233 | exited. */ | |
2234 | ||
2235 | static int | |
2236 | wait_lwp (struct lwp_info *lp) | |
2237 | { | |
2238 | pid_t pid; | |
432b4d03 | 2239 | int status = 0; |
d6b0e80f | 2240 | int thread_dead = 0; |
432b4d03 | 2241 | sigset_t prev_mask; |
d6b0e80f AC |
2242 | |
2243 | gdb_assert (!lp->stopped); | |
2244 | gdb_assert (lp->status == 0); | |
2245 | ||
432b4d03 JK |
2246 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2247 | block_child_signals (&prev_mask); | |
2248 | ||
2249 | for (;;) | |
d6b0e80f | 2250 | { |
432b4d03 JK |
2251 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2252 | was right and we should just call sigsuspend. */ | |
2253 | ||
dfd4cc63 | 2254 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2255 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2256 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2257 | if (pid == -1 && errno == ECHILD) |
2258 | { | |
2259 | /* The thread has previously exited. We need to delete it | |
2260 | now because, for some vendor 2.4 kernels with NPTL | |
2261 | support backported, there won't be an exit event unless | |
2262 | it is the main thread. 2.6 kernels will report an exit | |
2263 | event for each thread that exits, as expected. */ | |
2264 | thread_dead = 1; | |
2265 | if (debug_linux_nat) | |
2266 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2267 | target_pid_to_str (lp->ptid)); | |
2268 | } | |
432b4d03 JK |
2269 | if (pid != 0) |
2270 | break; | |
2271 | ||
2272 | /* Bugs 10970, 12702. | |
2273 | Thread group leader may have exited in which case we'll lock up in | |
2274 | waitpid if there are other threads, even if they are all zombies too. | |
2275 | Basically, we're not supposed to use waitpid this way. | |
2276 | __WCLONE is not applicable for the leader so we can't use that. | |
2277 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2278 | process; it gets ESRCH both for the zombie and for running processes. | |
2279 | ||
2280 | As a workaround, check if we're waiting for the thread group leader and | |
2281 | if it's a zombie, and avoid calling waitpid if it is. | |
2282 | ||
2283 | This is racy, what if the tgl becomes a zombie right after we check? | |
2284 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2285 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2286 | |
dfd4cc63 LM |
2287 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2288 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2289 | { |
d6b0e80f AC |
2290 | thread_dead = 1; |
2291 | if (debug_linux_nat) | |
432b4d03 JK |
2292 | fprintf_unfiltered (gdb_stdlog, |
2293 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2294 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2295 | break; |
d6b0e80f | 2296 | } |
432b4d03 JK |
2297 | |
2298 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2299 | get invoked despite our caller had them intentionally blocked by | |
2300 | block_child_signals. This is sensitive only to the loop of | |
2301 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2302 | again before it gets to sigsuspend so we can safely let the handlers | |
2303 | get executed here. */ | |
2304 | ||
2305 | sigsuspend (&suspend_mask); | |
2306 | } | |
2307 | ||
2308 | restore_child_signals_mask (&prev_mask); | |
2309 | ||
d6b0e80f AC |
2310 | if (!thread_dead) |
2311 | { | |
dfd4cc63 | 2312 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2313 | |
2314 | if (debug_linux_nat) | |
2315 | { | |
2316 | fprintf_unfiltered (gdb_stdlog, | |
2317 | "WL: waitpid %s received %s\n", | |
2318 | target_pid_to_str (lp->ptid), | |
2319 | status_to_str (status)); | |
2320 | } | |
d6b0e80f | 2321 | |
a9f4bb21 PA |
2322 | /* Check if the thread has exited. */ |
2323 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2324 | { | |
2325 | thread_dead = 1; | |
2326 | if (debug_linux_nat) | |
2327 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2328 | target_pid_to_str (lp->ptid)); | |
2329 | } | |
d6b0e80f AC |
2330 | } |
2331 | ||
2332 | if (thread_dead) | |
2333 | { | |
e26af52f | 2334 | exit_lwp (lp); |
d6b0e80f AC |
2335 | return 0; |
2336 | } | |
2337 | ||
2338 | gdb_assert (WIFSTOPPED (status)); | |
2339 | ||
ca2163eb PA |
2340 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2341 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2342 | { | |
2343 | /* No longer need the sysgood bit. The ptrace event ends up | |
2344 | recorded in lp->waitstatus if we care for it. We can carry | |
2345 | on handling the event like a regular SIGTRAP from here | |
2346 | on. */ | |
2347 | status = W_STOPCODE (SIGTRAP); | |
2348 | if (linux_handle_syscall_trap (lp, 1)) | |
2349 | return wait_lwp (lp); | |
2350 | } | |
2351 | ||
d6b0e80f AC |
2352 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2353 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2354 | { | |
2355 | if (debug_linux_nat) | |
2356 | fprintf_unfiltered (gdb_stdlog, | |
2357 | "WL: Handling extended status 0x%06x\n", | |
2358 | status); | |
3d799a95 | 2359 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
2360 | return wait_lwp (lp); |
2361 | } | |
2362 | ||
2363 | return status; | |
2364 | } | |
2365 | ||
2366 | /* Send a SIGSTOP to LP. */ | |
2367 | ||
2368 | static int | |
2369 | stop_callback (struct lwp_info *lp, void *data) | |
2370 | { | |
2371 | if (!lp->stopped && !lp->signalled) | |
2372 | { | |
2373 | int ret; | |
2374 | ||
2375 | if (debug_linux_nat) | |
2376 | { | |
2377 | fprintf_unfiltered (gdb_stdlog, | |
2378 | "SC: kill %s **<SIGSTOP>**\n", | |
2379 | target_pid_to_str (lp->ptid)); | |
2380 | } | |
2381 | errno = 0; | |
dfd4cc63 | 2382 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2383 | if (debug_linux_nat) |
2384 | { | |
2385 | fprintf_unfiltered (gdb_stdlog, | |
2386 | "SC: lwp kill %d %s\n", | |
2387 | ret, | |
2388 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2389 | } | |
2390 | ||
2391 | lp->signalled = 1; | |
2392 | gdb_assert (lp->status == 0); | |
2393 | } | |
2394 | ||
2395 | return 0; | |
2396 | } | |
2397 | ||
7b50312a PA |
2398 | /* Request a stop on LWP. */ |
2399 | ||
2400 | void | |
2401 | linux_stop_lwp (struct lwp_info *lwp) | |
2402 | { | |
2403 | stop_callback (lwp, NULL); | |
2404 | } | |
2405 | ||
57380f4e | 2406 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2407 | |
2408 | static int | |
57380f4e DJ |
2409 | linux_nat_has_pending_sigint (int pid) |
2410 | { | |
2411 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2412 | |
2413 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2414 | ||
2415 | if (sigismember (&pending, SIGINT) | |
2416 | && !sigismember (&ignored, SIGINT)) | |
2417 | return 1; | |
2418 | ||
2419 | return 0; | |
2420 | } | |
2421 | ||
2422 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2423 | ||
2424 | static int | |
2425 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2426 | { |
57380f4e DJ |
2427 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2428 | flag to consume the next one. */ | |
2429 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2430 | && WSTOPSIG (lp->status) == SIGINT) | |
2431 | lp->status = 0; | |
2432 | else | |
2433 | lp->ignore_sigint = 1; | |
2434 | ||
2435 | return 0; | |
2436 | } | |
2437 | ||
2438 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2439 | This function is called after we know the LWP has stopped; if the LWP | |
2440 | stopped before the expected SIGINT was delivered, then it will never have | |
2441 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2442 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2443 | |
57380f4e DJ |
2444 | static void |
2445 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2446 | { | |
2447 | if (!lp->ignore_sigint) | |
2448 | return; | |
2449 | ||
dfd4cc63 | 2450 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2451 | { |
2452 | if (debug_linux_nat) | |
2453 | fprintf_unfiltered (gdb_stdlog, | |
2454 | "MCIS: Clearing bogus flag for %s\n", | |
2455 | target_pid_to_str (lp->ptid)); | |
2456 | lp->ignore_sigint = 0; | |
2457 | } | |
2458 | } | |
2459 | ||
ebec9a0f PA |
2460 | /* Fetch the possible triggered data watchpoint info and store it in |
2461 | LP. | |
2462 | ||
2463 | On some archs, like x86, that use debug registers to set | |
2464 | watchpoints, it's possible that the way to know which watched | |
2465 | address trapped, is to check the register that is used to select | |
2466 | which address to watch. Problem is, between setting the watchpoint | |
2467 | and reading back which data address trapped, the user may change | |
2468 | the set of watchpoints, and, as a consequence, GDB changes the | |
2469 | debug registers in the inferior. To avoid reading back a stale | |
2470 | stopped-data-address when that happens, we cache in LP the fact | |
2471 | that a watchpoint trapped, and the corresponding data address, as | |
2472 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2473 | registers meanwhile, we have the cached data we can rely on. */ | |
2474 | ||
2475 | static void | |
2476 | save_sigtrap (struct lwp_info *lp) | |
2477 | { | |
2478 | struct cleanup *old_chain; | |
2479 | ||
2480 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
2481 | { | |
2482 | lp->stopped_by_watchpoint = 0; | |
2483 | return; | |
2484 | } | |
2485 | ||
2486 | old_chain = save_inferior_ptid (); | |
2487 | inferior_ptid = lp->ptid; | |
2488 | ||
2489 | lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint (); | |
2490 | ||
2491 | if (lp->stopped_by_watchpoint) | |
2492 | { | |
2493 | if (linux_ops->to_stopped_data_address != NULL) | |
2494 | lp->stopped_data_address_p = | |
2495 | linux_ops->to_stopped_data_address (¤t_target, | |
2496 | &lp->stopped_data_address); | |
2497 | else | |
2498 | lp->stopped_data_address_p = 0; | |
2499 | } | |
2500 | ||
2501 | do_cleanups (old_chain); | |
2502 | } | |
2503 | ||
2504 | /* See save_sigtrap. */ | |
2505 | ||
2506 | static int | |
2507 | linux_nat_stopped_by_watchpoint (void) | |
2508 | { | |
2509 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2510 | ||
2511 | gdb_assert (lp != NULL); | |
2512 | ||
2513 | return lp->stopped_by_watchpoint; | |
2514 | } | |
2515 | ||
2516 | static int | |
2517 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2518 | { | |
2519 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2520 | ||
2521 | gdb_assert (lp != NULL); | |
2522 | ||
2523 | *addr_p = lp->stopped_data_address; | |
2524 | ||
2525 | return lp->stopped_data_address_p; | |
2526 | } | |
2527 | ||
26ab7092 JK |
2528 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2529 | ||
2530 | static int | |
2531 | sigtrap_is_event (int status) | |
2532 | { | |
2533 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2534 | } | |
2535 | ||
2536 | /* SIGTRAP-like events recognizer. */ | |
2537 | ||
2538 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
2539 | ||
00390b84 JK |
2540 | /* Check for SIGTRAP-like events in LP. */ |
2541 | ||
2542 | static int | |
2543 | linux_nat_lp_status_is_event (struct lwp_info *lp) | |
2544 | { | |
2545 | /* We check for lp->waitstatus in addition to lp->status, because we can | |
2546 | have pending process exits recorded in lp->status | |
2547 | and W_EXITCODE(0,0) == 0. We should probably have an additional | |
2548 | lp->status_p flag. */ | |
2549 | ||
2550 | return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE | |
2551 | && linux_nat_status_is_event (lp->status)); | |
2552 | } | |
2553 | ||
26ab7092 JK |
2554 | /* Set alternative SIGTRAP-like events recognizer. If |
2555 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2556 | applied. */ | |
2557 | ||
2558 | void | |
2559 | linux_nat_set_status_is_event (struct target_ops *t, | |
2560 | int (*status_is_event) (int status)) | |
2561 | { | |
2562 | linux_nat_status_is_event = status_is_event; | |
2563 | } | |
2564 | ||
57380f4e DJ |
2565 | /* Wait until LP is stopped. */ |
2566 | ||
2567 | static int | |
2568 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2569 | { | |
dfd4cc63 | 2570 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
6c95b8df PA |
2571 | |
2572 | /* If this is a vfork parent, bail out, it is not going to report | |
2573 | any SIGSTOP until the vfork is done with. */ | |
2574 | if (inf->vfork_child != NULL) | |
2575 | return 0; | |
2576 | ||
d6b0e80f AC |
2577 | if (!lp->stopped) |
2578 | { | |
2579 | int status; | |
2580 | ||
2581 | status = wait_lwp (lp); | |
2582 | if (status == 0) | |
2583 | return 0; | |
2584 | ||
57380f4e DJ |
2585 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2586 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2587 | { |
57380f4e | 2588 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2589 | |
2590 | errno = 0; | |
dfd4cc63 | 2591 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f AC |
2592 | if (debug_linux_nat) |
2593 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2594 | "PTRACE_CONT %s, 0, 0 (%s) " |
2595 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2596 | target_pid_to_str (lp->ptid), |
2597 | errno ? safe_strerror (errno) : "OK"); | |
2598 | ||
57380f4e | 2599 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2600 | } |
2601 | ||
57380f4e DJ |
2602 | maybe_clear_ignore_sigint (lp); |
2603 | ||
d6b0e80f AC |
2604 | if (WSTOPSIG (status) != SIGSTOP) |
2605 | { | |
e5ef252a | 2606 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2607 | |
e5ef252a PA |
2608 | save_sigtrap (lp); |
2609 | ||
2610 | if (debug_linux_nat) | |
2611 | fprintf_unfiltered (gdb_stdlog, | |
2612 | "SWC: Pending event %s in %s\n", | |
2613 | status_to_str ((int) status), | |
2614 | target_pid_to_str (lp->ptid)); | |
2615 | ||
2616 | /* Save the sigtrap event. */ | |
2617 | lp->status = status; | |
2618 | gdb_assert (!lp->stopped); | |
2619 | gdb_assert (lp->signalled); | |
2620 | lp->stopped = 1; | |
d6b0e80f AC |
2621 | } |
2622 | else | |
2623 | { | |
2624 | /* We caught the SIGSTOP that we intended to catch, so | |
2625 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2626 | |
2627 | if (debug_linux_nat) | |
2628 | fprintf_unfiltered (gdb_stdlog, | |
2629 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2630 | target_pid_to_str (lp->ptid)); | |
2631 | ||
d6b0e80f | 2632 | lp->stopped = 1; |
e5ef252a PA |
2633 | |
2634 | /* Reset SIGNALLED only after the stop_wait_callback call | |
2635 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2636 | lp->signalled = 0; |
2637 | } | |
2638 | } | |
2639 | ||
2640 | return 0; | |
2641 | } | |
2642 | ||
d6b0e80f AC |
2643 | /* Return non-zero if LP has a wait status pending. */ |
2644 | ||
2645 | static int | |
2646 | status_callback (struct lwp_info *lp, void *data) | |
2647 | { | |
2648 | /* Only report a pending wait status if we pretend that this has | |
2649 | indeed been resumed. */ | |
ca2163eb PA |
2650 | if (!lp->resumed) |
2651 | return 0; | |
2652 | ||
2653 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2654 | { | |
2655 | /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event, | |
766062f6 | 2656 | or a pending process exit. Note that `W_EXITCODE(0,0) == |
ca2163eb PA |
2657 | 0', so a clean process exit can not be stored pending in |
2658 | lp->status, it is indistinguishable from | |
2659 | no-pending-status. */ | |
2660 | return 1; | |
2661 | } | |
2662 | ||
2663 | if (lp->status != 0) | |
2664 | return 1; | |
2665 | ||
2666 | return 0; | |
d6b0e80f AC |
2667 | } |
2668 | ||
2669 | /* Return non-zero if LP isn't stopped. */ | |
2670 | ||
2671 | static int | |
2672 | running_callback (struct lwp_info *lp, void *data) | |
2673 | { | |
25289eb2 PA |
2674 | return (!lp->stopped |
2675 | || ((lp->status != 0 | |
2676 | || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2677 | && lp->resumed)); | |
d6b0e80f AC |
2678 | } |
2679 | ||
2680 | /* Count the LWP's that have had events. */ | |
2681 | ||
2682 | static int | |
2683 | count_events_callback (struct lwp_info *lp, void *data) | |
2684 | { | |
2685 | int *count = data; | |
2686 | ||
2687 | gdb_assert (count != NULL); | |
2688 | ||
e09490f1 | 2689 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2690 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2691 | (*count)++; |
2692 | ||
2693 | return 0; | |
2694 | } | |
2695 | ||
2696 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2697 | ||
2698 | static int | |
2699 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2700 | { | |
25289eb2 PA |
2701 | if (lp->last_resume_kind == resume_step |
2702 | && lp->status != 0) | |
d6b0e80f AC |
2703 | return 1; |
2704 | else | |
2705 | return 0; | |
2706 | } | |
2707 | ||
2708 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2709 | ||
2710 | static int | |
2711 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2712 | { | |
2713 | int *selector = data; | |
2714 | ||
2715 | gdb_assert (selector != NULL); | |
2716 | ||
1777feb0 | 2717 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2718 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2719 | if ((*selector)-- == 0) |
2720 | return 1; | |
2721 | ||
2722 | return 0; | |
2723 | } | |
2724 | ||
710151dd PA |
2725 | static int |
2726 | cancel_breakpoint (struct lwp_info *lp) | |
2727 | { | |
2728 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2729 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2730 | LWP. We will handle the current event, eventually we will resume | |
2731 | this LWP, and this breakpoint will trap again. | |
2732 | ||
2733 | If we do not do this, then we run the risk that the user will | |
2734 | delete or disable the breakpoint, but the LWP will have already | |
2735 | tripped on it. */ | |
2736 | ||
515630c5 UW |
2737 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2738 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2739 | CORE_ADDR pc; | |
2740 | ||
2741 | pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch); | |
6c95b8df | 2742 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
710151dd PA |
2743 | { |
2744 | if (debug_linux_nat) | |
2745 | fprintf_unfiltered (gdb_stdlog, | |
2746 | "CB: Push back breakpoint for %s\n", | |
2747 | target_pid_to_str (lp->ptid)); | |
2748 | ||
2749 | /* Back up the PC if necessary. */ | |
515630c5 UW |
2750 | if (gdbarch_decr_pc_after_break (gdbarch)) |
2751 | regcache_write_pc (regcache, pc); | |
2752 | ||
710151dd PA |
2753 | return 1; |
2754 | } | |
2755 | return 0; | |
2756 | } | |
2757 | ||
d6b0e80f AC |
2758 | static int |
2759 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2760 | { | |
2761 | struct lwp_info *event_lp = data; | |
2762 | ||
2763 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2764 | if (lp == event_lp) | |
2765 | return 0; | |
2766 | ||
2767 | /* If a LWP other than the LWP that we're reporting an event for has | |
2768 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2769 | then just arrange for it to hit it again later. We don't keep | |
2770 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2771 | LWP. We will handle the current event, eventually we will resume | |
2772 | all LWPs, and this one will get its breakpoint trap again. | |
2773 | ||
2774 | If we do not do this, then we run the risk that the user will | |
2775 | delete or disable the breakpoint, but the LWP will have already | |
2776 | tripped on it. */ | |
2777 | ||
00390b84 | 2778 | if (linux_nat_lp_status_is_event (lp) |
710151dd PA |
2779 | && cancel_breakpoint (lp)) |
2780 | /* Throw away the SIGTRAP. */ | |
2781 | lp->status = 0; | |
d6b0e80f AC |
2782 | |
2783 | return 0; | |
2784 | } | |
2785 | ||
2786 | /* Select one LWP out of those that have events pending. */ | |
2787 | ||
2788 | static void | |
d90e17a7 | 2789 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2790 | { |
2791 | int num_events = 0; | |
2792 | int random_selector; | |
2793 | struct lwp_info *event_lp; | |
2794 | ||
ac264b3b | 2795 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2796 | (*orig_lp)->status = *status; |
2797 | ||
2798 | /* Give preference to any LWP that is being single-stepped. */ | |
d90e17a7 PA |
2799 | event_lp = iterate_over_lwps (filter, |
2800 | select_singlestep_lwp_callback, NULL); | |
d6b0e80f AC |
2801 | if (event_lp != NULL) |
2802 | { | |
2803 | if (debug_linux_nat) | |
2804 | fprintf_unfiltered (gdb_stdlog, | |
2805 | "SEL: Select single-step %s\n", | |
2806 | target_pid_to_str (event_lp->ptid)); | |
2807 | } | |
2808 | else | |
2809 | { | |
2810 | /* No single-stepping LWP. Select one at random, out of those | |
2811 | which have had SIGTRAP events. */ | |
2812 | ||
2813 | /* First see how many SIGTRAP events we have. */ | |
d90e17a7 | 2814 | iterate_over_lwps (filter, count_events_callback, &num_events); |
d6b0e80f AC |
2815 | |
2816 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2817 | random_selector = (int) | |
2818 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2819 | ||
2820 | if (debug_linux_nat && num_events > 1) | |
2821 | fprintf_unfiltered (gdb_stdlog, | |
2822 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2823 | num_events, random_selector); | |
2824 | ||
d90e17a7 PA |
2825 | event_lp = iterate_over_lwps (filter, |
2826 | select_event_lwp_callback, | |
d6b0e80f AC |
2827 | &random_selector); |
2828 | } | |
2829 | ||
2830 | if (event_lp != NULL) | |
2831 | { | |
2832 | /* Switch the event LWP. */ | |
2833 | *orig_lp = event_lp; | |
2834 | *status = event_lp->status; | |
2835 | } | |
2836 | ||
2837 | /* Flush the wait status for the event LWP. */ | |
2838 | (*orig_lp)->status = 0; | |
2839 | } | |
2840 | ||
2841 | /* Return non-zero if LP has been resumed. */ | |
2842 | ||
2843 | static int | |
2844 | resumed_callback (struct lwp_info *lp, void *data) | |
2845 | { | |
2846 | return lp->resumed; | |
2847 | } | |
2848 | ||
12d9289a PA |
2849 | /* Stop an active thread, verify it still exists, then resume it. If |
2850 | the thread ends up with a pending status, then it is not resumed, | |
2851 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2852 | |
2853 | static int | |
2854 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2855 | { | |
12d9289a PA |
2856 | int *new_pending_p = data; |
2857 | ||
25289eb2 | 2858 | if (!lp->stopped) |
d6b0e80f | 2859 | { |
25289eb2 PA |
2860 | ptid_t ptid = lp->ptid; |
2861 | ||
d6b0e80f AC |
2862 | stop_callback (lp, NULL); |
2863 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2864 | |
2865 | /* Resume if the lwp still exists, and the core wanted it | |
2866 | running. */ | |
12d9289a PA |
2867 | lp = find_lwp_pid (ptid); |
2868 | if (lp != NULL) | |
25289eb2 | 2869 | { |
12d9289a PA |
2870 | if (lp->last_resume_kind == resume_stop |
2871 | && lp->status == 0) | |
2872 | { | |
2873 | /* The core wanted the LWP to stop. Even if it stopped | |
2874 | cleanly (with SIGSTOP), leave the event pending. */ | |
2875 | if (debug_linux_nat) | |
2876 | fprintf_unfiltered (gdb_stdlog, | |
2877 | "SARC: core wanted LWP %ld stopped " | |
2878 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2879 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2880 | lp->status = W_STOPCODE (SIGSTOP); |
2881 | } | |
2882 | ||
2883 | if (lp->status == 0) | |
2884 | { | |
2885 | if (debug_linux_nat) | |
2886 | fprintf_unfiltered (gdb_stdlog, | |
2887 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2888 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2889 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2890 | } |
2891 | else | |
2892 | { | |
2893 | if (debug_linux_nat) | |
2894 | fprintf_unfiltered (gdb_stdlog, | |
2895 | "SARC: not re-resuming LWP %ld " | |
2896 | "(has pending)\n", | |
dfd4cc63 | 2897 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2898 | if (new_pending_p) |
2899 | *new_pending_p = 1; | |
2900 | } | |
25289eb2 | 2901 | } |
d6b0e80f AC |
2902 | } |
2903 | return 0; | |
2904 | } | |
2905 | ||
02f3fc28 | 2906 | /* Check if we should go on and pass this event to common code. |
12d9289a PA |
2907 | Return the affected lwp if we are, or NULL otherwise. If we stop |
2908 | all lwps temporarily, we may end up with new pending events in some | |
2909 | other lwp. In that case set *NEW_PENDING_P to true. */ | |
2910 | ||
02f3fc28 | 2911 | static struct lwp_info * |
0e5bf2a8 | 2912 | linux_nat_filter_event (int lwpid, int status, int *new_pending_p) |
02f3fc28 PA |
2913 | { |
2914 | struct lwp_info *lp; | |
2915 | ||
12d9289a PA |
2916 | *new_pending_p = 0; |
2917 | ||
02f3fc28 PA |
2918 | lp = find_lwp_pid (pid_to_ptid (lwpid)); |
2919 | ||
2920 | /* Check for stop events reported by a process we didn't already | |
2921 | know about - anything not already in our LWP list. | |
2922 | ||
2923 | If we're expecting to receive stopped processes after | |
2924 | fork, vfork, and clone events, then we'll just add the | |
2925 | new one to our list and go back to waiting for the event | |
2926 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2927 | from waitpid before or after the event is. |
2928 | ||
2929 | But note the case of a non-leader thread exec'ing after the | |
2930 | leader having exited, and gone from our lists. The non-leader | |
2931 | thread changes its tid to the tgid. */ | |
2932 | ||
2933 | if (WIFSTOPPED (status) && lp == NULL | |
2934 | && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC)) | |
2935 | { | |
2936 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2937 | if (debug_linux_nat) | |
2938 | fprintf_unfiltered (gdb_stdlog, | |
2939 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2940 | lwpid); | |
2941 | ||
dfd4cc63 | 2942 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2943 | lp->stopped = 1; |
2944 | lp->resumed = 1; | |
2945 | add_thread (lp->ptid); | |
2946 | } | |
2947 | ||
02f3fc28 PA |
2948 | if (WIFSTOPPED (status) && !lp) |
2949 | { | |
84636d28 | 2950 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2951 | return NULL; |
2952 | } | |
2953 | ||
2954 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2955 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2956 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2957 | exits. */ |
2958 | if (!WIFSTOPPED (status) && !lp) | |
2959 | return NULL; | |
2960 | ||
ca2163eb PA |
2961 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2962 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2963 | { | |
2964 | /* No longer need the sysgood bit. The ptrace event ends up | |
2965 | recorded in lp->waitstatus if we care for it. We can carry | |
2966 | on handling the event like a regular SIGTRAP from here | |
2967 | on. */ | |
2968 | status = W_STOPCODE (SIGTRAP); | |
2969 | if (linux_handle_syscall_trap (lp, 0)) | |
2970 | return NULL; | |
2971 | } | |
02f3fc28 | 2972 | |
ca2163eb PA |
2973 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2974 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
02f3fc28 PA |
2975 | { |
2976 | if (debug_linux_nat) | |
2977 | fprintf_unfiltered (gdb_stdlog, | |
2978 | "LLW: Handling extended status 0x%06x\n", | |
2979 | status); | |
2980 | if (linux_handle_extended_wait (lp, status, 0)) | |
2981 | return NULL; | |
2982 | } | |
2983 | ||
26ab7092 | 2984 | if (linux_nat_status_is_event (status)) |
da559b09 | 2985 | save_sigtrap (lp); |
ca2163eb | 2986 | |
02f3fc28 | 2987 | /* Check if the thread has exited. */ |
d90e17a7 | 2988 | if ((WIFEXITED (status) || WIFSIGNALED (status)) |
dfd4cc63 | 2989 | && num_lwps (ptid_get_pid (lp->ptid)) > 1) |
02f3fc28 | 2990 | { |
9db03742 JB |
2991 | /* If this is the main thread, we must stop all threads and verify |
2992 | if they are still alive. This is because in the nptl thread model | |
2993 | on Linux 2.4, there is no signal issued for exiting LWPs | |
02f3fc28 PA |
2994 | other than the main thread. We only get the main thread exit |
2995 | signal once all child threads have already exited. If we | |
2996 | stop all the threads and use the stop_wait_callback to check | |
2997 | if they have exited we can determine whether this signal | |
2998 | should be ignored or whether it means the end of the debugged | |
2999 | application, regardless of which threading model is being | |
5d3b6af6 | 3000 | used. */ |
dfd4cc63 | 3001 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
02f3fc28 PA |
3002 | { |
3003 | lp->stopped = 1; | |
dfd4cc63 | 3004 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), |
12d9289a | 3005 | stop_and_resume_callback, new_pending_p); |
02f3fc28 PA |
3006 | } |
3007 | ||
3008 | if (debug_linux_nat) | |
3009 | fprintf_unfiltered (gdb_stdlog, | |
3010 | "LLW: %s exited.\n", | |
3011 | target_pid_to_str (lp->ptid)); | |
3012 | ||
dfd4cc63 | 3013 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) |
9db03742 JB |
3014 | { |
3015 | /* If there is at least one more LWP, then the exit signal | |
3016 | was not the end of the debugged application and should be | |
3017 | ignored. */ | |
3018 | exit_lwp (lp); | |
3019 | return NULL; | |
3020 | } | |
02f3fc28 PA |
3021 | } |
3022 | ||
3023 | /* Check if the current LWP has previously exited. In the nptl | |
3024 | thread model, LWPs other than the main thread do not issue | |
3025 | signals when they exit so we must check whenever the thread has | |
3026 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3027 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3028 | { |
dfd4cc63 | 3029 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3030 | |
02f3fc28 PA |
3031 | if (debug_linux_nat) |
3032 | fprintf_unfiltered (gdb_stdlog, | |
3033 | "LLW: %s exited.\n", | |
3034 | target_pid_to_str (lp->ptid)); | |
3035 | ||
3036 | exit_lwp (lp); | |
3037 | ||
3038 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3039 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3040 | |
3041 | /* Discard the event. */ | |
3042 | return NULL; | |
3043 | } | |
3044 | ||
3045 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3046 | an attempt to stop an LWP. */ | |
3047 | if (lp->signalled | |
3048 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3049 | { | |
3050 | if (debug_linux_nat) | |
3051 | fprintf_unfiltered (gdb_stdlog, | |
3052 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3053 | target_pid_to_str (lp->ptid)); | |
3054 | ||
02f3fc28 PA |
3055 | lp->signalled = 0; |
3056 | ||
25289eb2 PA |
3057 | if (lp->last_resume_kind != resume_stop) |
3058 | { | |
3059 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3060 | |
25289eb2 PA |
3061 | registers_changed (); |
3062 | ||
7b50312a PA |
3063 | if (linux_nat_prepare_to_resume != NULL) |
3064 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3065 | linux_ops->to_resume (linux_ops, |
3066 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
3067 | lp->step, GDB_SIGNAL_0); | |
25289eb2 PA |
3068 | if (debug_linux_nat) |
3069 | fprintf_unfiltered (gdb_stdlog, | |
3070 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3071 | lp->step ? | |
3072 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3073 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3074 | |
25289eb2 PA |
3075 | lp->stopped = 0; |
3076 | gdb_assert (lp->resumed); | |
02f3fc28 | 3077 | |
25289eb2 PA |
3078 | /* Discard the event. */ |
3079 | return NULL; | |
3080 | } | |
02f3fc28 PA |
3081 | } |
3082 | ||
57380f4e DJ |
3083 | /* Make sure we don't report a SIGINT that we have already displayed |
3084 | for another thread. */ | |
3085 | if (lp->ignore_sigint | |
3086 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3087 | { | |
3088 | if (debug_linux_nat) | |
3089 | fprintf_unfiltered (gdb_stdlog, | |
3090 | "LLW: Delayed SIGINT caught for %s.\n", | |
3091 | target_pid_to_str (lp->ptid)); | |
3092 | ||
3093 | /* This is a delayed SIGINT. */ | |
3094 | lp->ignore_sigint = 0; | |
3095 | ||
3096 | registers_changed (); | |
7b50312a PA |
3097 | if (linux_nat_prepare_to_resume != NULL) |
3098 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3099 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3100 | lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3101 | if (debug_linux_nat) |
3102 | fprintf_unfiltered (gdb_stdlog, | |
3103 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3104 | lp->step ? | |
3105 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3106 | target_pid_to_str (lp->ptid)); | |
3107 | ||
3108 | lp->stopped = 0; | |
3109 | gdb_assert (lp->resumed); | |
3110 | ||
3111 | /* Discard the event. */ | |
3112 | return NULL; | |
3113 | } | |
3114 | ||
02f3fc28 PA |
3115 | /* An interesting event. */ |
3116 | gdb_assert (lp); | |
ca2163eb | 3117 | lp->status = status; |
02f3fc28 PA |
3118 | return lp; |
3119 | } | |
3120 | ||
0e5bf2a8 PA |
3121 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3122 | their exits until all other threads in the group have exited. */ | |
3123 | ||
3124 | static void | |
3125 | check_zombie_leaders (void) | |
3126 | { | |
3127 | struct inferior *inf; | |
3128 | ||
3129 | ALL_INFERIORS (inf) | |
3130 | { | |
3131 | struct lwp_info *leader_lp; | |
3132 | ||
3133 | if (inf->pid == 0) | |
3134 | continue; | |
3135 | ||
3136 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3137 | if (leader_lp != NULL | |
3138 | /* Check if there are other threads in the group, as we may | |
3139 | have raced with the inferior simply exiting. */ | |
3140 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3141 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3142 | { |
3143 | if (debug_linux_nat) | |
3144 | fprintf_unfiltered (gdb_stdlog, | |
3145 | "CZL: Thread group leader %d zombie " | |
3146 | "(it exited, or another thread execd).\n", | |
3147 | inf->pid); | |
3148 | ||
3149 | /* A leader zombie can mean one of two things: | |
3150 | ||
3151 | - It exited, and there's an exit status pending | |
3152 | available, or only the leader exited (not the whole | |
3153 | program). In the latter case, we can't waitpid the | |
3154 | leader's exit status until all other threads are gone. | |
3155 | ||
3156 | - There are 3 or more threads in the group, and a thread | |
3157 | other than the leader exec'd. On an exec, the Linux | |
3158 | kernel destroys all other threads (except the execing | |
3159 | one) in the thread group, and resets the execing thread's | |
3160 | tid to the tgid. No exit notification is sent for the | |
3161 | execing thread -- from the ptracer's perspective, it | |
3162 | appears as though the execing thread just vanishes. | |
3163 | Until we reap all other threads except the leader and the | |
3164 | execing thread, the leader will be zombie, and the | |
3165 | execing thread will be in `D (disc sleep)'. As soon as | |
3166 | all other threads are reaped, the execing thread changes | |
3167 | it's tid to the tgid, and the previous (zombie) leader | |
3168 | vanishes, giving place to the "new" leader. We could try | |
3169 | distinguishing the exit and exec cases, by waiting once | |
3170 | more, and seeing if something comes out, but it doesn't | |
3171 | sound useful. The previous leader _does_ go away, and | |
3172 | we'll re-add the new one once we see the exec event | |
3173 | (which is just the same as what would happen if the | |
3174 | previous leader did exit voluntarily before some other | |
3175 | thread execs). */ | |
3176 | ||
3177 | if (debug_linux_nat) | |
3178 | fprintf_unfiltered (gdb_stdlog, | |
3179 | "CZL: Thread group leader %d vanished.\n", | |
3180 | inf->pid); | |
3181 | exit_lwp (leader_lp); | |
3182 | } | |
3183 | } | |
3184 | } | |
3185 | ||
d6b0e80f | 3186 | static ptid_t |
7feb7d06 | 3187 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3188 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3189 | int target_options) | |
d6b0e80f | 3190 | { |
7feb7d06 | 3191 | static sigset_t prev_mask; |
4b60df3d | 3192 | enum resume_kind last_resume_kind; |
12d9289a | 3193 | struct lwp_info *lp; |
12d9289a | 3194 | int status; |
d6b0e80f | 3195 | |
01124a23 | 3196 | if (debug_linux_nat) |
b84876c2 PA |
3197 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3198 | ||
f973ed9c DJ |
3199 | /* The first time we get here after starting a new inferior, we may |
3200 | not have added it to the LWP list yet - this is the earliest | |
3201 | moment at which we know its PID. */ | |
d90e17a7 | 3202 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3203 | { |
27c9d204 PA |
3204 | /* Upgrade the main thread's ptid. */ |
3205 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3206 | ptid_build (ptid_get_pid (inferior_ptid), |
3207 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3208 | |
26cb8b7c | 3209 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3210 | lp->resumed = 1; |
3211 | } | |
3212 | ||
12696c10 | 3213 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3214 | block_child_signals (&prev_mask); |
d6b0e80f AC |
3215 | |
3216 | retry: | |
d90e17a7 PA |
3217 | lp = NULL; |
3218 | status = 0; | |
d6b0e80f AC |
3219 | |
3220 | /* First check if there is a LWP with a wait status pending. */ | |
0e5bf2a8 | 3221 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d6b0e80f | 3222 | { |
0e5bf2a8 | 3223 | /* Any LWP in the PTID group that's been resumed will do. */ |
d90e17a7 | 3224 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
d6b0e80f AC |
3225 | if (lp) |
3226 | { | |
ca2163eb | 3227 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3228 | fprintf_unfiltered (gdb_stdlog, |
3229 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3230 | status_to_str (lp->status), |
d6b0e80f AC |
3231 | target_pid_to_str (lp->ptid)); |
3232 | } | |
d6b0e80f | 3233 | } |
dfd4cc63 | 3234 | else if (ptid_lwp_p (ptid)) |
d6b0e80f AC |
3235 | { |
3236 | if (debug_linux_nat) | |
3237 | fprintf_unfiltered (gdb_stdlog, | |
3238 | "LLW: Waiting for specific LWP %s.\n", | |
3239 | target_pid_to_str (ptid)); | |
3240 | ||
3241 | /* We have a specific LWP to check. */ | |
3242 | lp = find_lwp_pid (ptid); | |
3243 | gdb_assert (lp); | |
d6b0e80f | 3244 | |
ca2163eb | 3245 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3246 | fprintf_unfiltered (gdb_stdlog, |
3247 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3248 | status_to_str (lp->status), |
d6b0e80f AC |
3249 | target_pid_to_str (lp->ptid)); |
3250 | ||
d90e17a7 PA |
3251 | /* We check for lp->waitstatus in addition to lp->status, |
3252 | because we can have pending process exits recorded in | |
3253 | lp->status and W_EXITCODE(0,0) == 0. We should probably have | |
3254 | an additional lp->status_p flag. */ | |
ca2163eb | 3255 | if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) |
d90e17a7 | 3256 | lp = NULL; |
d6b0e80f AC |
3257 | } |
3258 | ||
b84876c2 PA |
3259 | if (!target_can_async_p ()) |
3260 | { | |
3261 | /* Causes SIGINT to be passed on to the attached process. */ | |
3262 | set_sigint_trap (); | |
b84876c2 | 3263 | } |
d6b0e80f | 3264 | |
0e5bf2a8 | 3265 | /* But if we don't find a pending event, we'll have to wait. */ |
7feb7d06 | 3266 | |
d90e17a7 | 3267 | while (lp == NULL) |
d6b0e80f AC |
3268 | { |
3269 | pid_t lwpid; | |
3270 | ||
0e5bf2a8 PA |
3271 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3272 | quirks: | |
3273 | ||
3274 | - If the thread group leader exits while other threads in the | |
3275 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3276 | waitpid won't return an exit status until the other threads | |
3277 | in the group are reapped. | |
3278 | ||
3279 | - When a non-leader thread execs, that thread just vanishes | |
3280 | without reporting an exit (so we'd hang if we waited for it | |
3281 | explicitly in that case). The exec event is reported to | |
3282 | the TGID pid. */ | |
3283 | ||
3284 | errno = 0; | |
3285 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3286 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3287 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3288 | ||
3289 | if (debug_linux_nat) | |
3290 | fprintf_unfiltered (gdb_stdlog, | |
3291 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3292 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3293 | |
d6b0e80f AC |
3294 | if (lwpid > 0) |
3295 | { | |
12d9289a PA |
3296 | /* If this is true, then we paused LWPs momentarily, and may |
3297 | now have pending events to handle. */ | |
3298 | int new_pending; | |
3299 | ||
d6b0e80f AC |
3300 | if (debug_linux_nat) |
3301 | { | |
3302 | fprintf_unfiltered (gdb_stdlog, | |
3303 | "LLW: waitpid %ld received %s\n", | |
3304 | (long) lwpid, status_to_str (status)); | |
3305 | } | |
3306 | ||
0e5bf2a8 | 3307 | lp = linux_nat_filter_event (lwpid, status, &new_pending); |
d90e17a7 | 3308 | |
33355866 JK |
3309 | /* STATUS is now no longer valid, use LP->STATUS instead. */ |
3310 | status = 0; | |
3311 | ||
0e5bf2a8 | 3312 | if (lp && !ptid_match (lp->ptid, ptid)) |
d6b0e80f | 3313 | { |
e3e9f5a2 PA |
3314 | gdb_assert (lp->resumed); |
3315 | ||
d90e17a7 | 3316 | if (debug_linux_nat) |
3e43a32a MS |
3317 | fprintf (stderr, |
3318 | "LWP %ld got an event %06x, leaving pending.\n", | |
33355866 | 3319 | ptid_get_lwp (lp->ptid), lp->status); |
d90e17a7 | 3320 | |
ca2163eb | 3321 | if (WIFSTOPPED (lp->status)) |
d90e17a7 | 3322 | { |
ca2163eb | 3323 | if (WSTOPSIG (lp->status) != SIGSTOP) |
d90e17a7 | 3324 | { |
e3e9f5a2 PA |
3325 | /* Cancel breakpoint hits. The breakpoint may |
3326 | be removed before we fetch events from this | |
3327 | process to report to the core. It is best | |
3328 | not to assume the moribund breakpoints | |
3329 | heuristic always handles these cases --- it | |
3330 | could be too many events go through to the | |
3331 | core before this one is handled. All-stop | |
3332 | always cancels breakpoint hits in all | |
3333 | threads. */ | |
3334 | if (non_stop | |
00390b84 | 3335 | && linux_nat_lp_status_is_event (lp) |
e3e9f5a2 PA |
3336 | && cancel_breakpoint (lp)) |
3337 | { | |
3338 | /* Throw away the SIGTRAP. */ | |
3339 | lp->status = 0; | |
3340 | ||
3341 | if (debug_linux_nat) | |
3342 | fprintf (stderr, | |
3e43a32a MS |
3343 | "LLW: LWP %ld hit a breakpoint while" |
3344 | " waiting for another process;" | |
3345 | " cancelled it\n", | |
e3e9f5a2 PA |
3346 | ptid_get_lwp (lp->ptid)); |
3347 | } | |
3348 | lp->stopped = 1; | |
d90e17a7 PA |
3349 | } |
3350 | else | |
3351 | { | |
3352 | lp->stopped = 1; | |
3353 | lp->signalled = 0; | |
3354 | } | |
3355 | } | |
33355866 | 3356 | else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status)) |
d90e17a7 PA |
3357 | { |
3358 | if (debug_linux_nat) | |
3e43a32a MS |
3359 | fprintf (stderr, |
3360 | "Process %ld exited while stopping LWPs\n", | |
d90e17a7 PA |
3361 | ptid_get_lwp (lp->ptid)); |
3362 | ||
3363 | /* This was the last lwp in the process. Since | |
3364 | events are serialized to GDB core, and we can't | |
3365 | report this one right now, but GDB core and the | |
3366 | other target layers will want to be notified | |
3367 | about the exit code/signal, leave the status | |
3368 | pending for the next time we're able to report | |
3369 | it. */ | |
d90e17a7 PA |
3370 | |
3371 | /* Prevent trying to stop this thread again. We'll | |
3372 | never try to resume it because it has a pending | |
3373 | status. */ | |
3374 | lp->stopped = 1; | |
3375 | ||
3376 | /* Dead LWP's aren't expected to reported a pending | |
3377 | sigstop. */ | |
3378 | lp->signalled = 0; | |
3379 | ||
3380 | /* Store the pending event in the waitstatus as | |
3381 | well, because W_EXITCODE(0,0) == 0. */ | |
ca2163eb | 3382 | store_waitstatus (&lp->waitstatus, lp->status); |
d90e17a7 PA |
3383 | } |
3384 | ||
3385 | /* Keep looking. */ | |
3386 | lp = NULL; | |
d6b0e80f AC |
3387 | } |
3388 | ||
0e5bf2a8 | 3389 | if (new_pending) |
d90e17a7 | 3390 | { |
0e5bf2a8 PA |
3391 | /* Some LWP now has a pending event. Go all the way |
3392 | back to check it. */ | |
3393 | goto retry; | |
3394 | } | |
12d9289a | 3395 | |
0e5bf2a8 PA |
3396 | if (lp) |
3397 | { | |
3398 | /* We got an event to report to the core. */ | |
3399 | break; | |
d90e17a7 | 3400 | } |
0e5bf2a8 PA |
3401 | |
3402 | /* Retry until nothing comes out of waitpid. A single | |
3403 | SIGCHLD can indicate more than one child stopped. */ | |
3404 | continue; | |
d6b0e80f AC |
3405 | } |
3406 | ||
0e5bf2a8 PA |
3407 | /* Check for zombie thread group leaders. Those can't be reaped |
3408 | until all other threads in the thread group are. */ | |
3409 | check_zombie_leaders (); | |
d6b0e80f | 3410 | |
0e5bf2a8 PA |
3411 | /* If there are no resumed children left, bail. We'd be stuck |
3412 | forever in the sigsuspend call below otherwise. */ | |
3413 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3414 | { | |
3415 | if (debug_linux_nat) | |
3416 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3417 | |
0e5bf2a8 | 3418 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3419 | |
0e5bf2a8 PA |
3420 | if (!target_can_async_p ()) |
3421 | clear_sigint_trap (); | |
b84876c2 | 3422 | |
0e5bf2a8 PA |
3423 | restore_child_signals_mask (&prev_mask); |
3424 | return minus_one_ptid; | |
d6b0e80f | 3425 | } |
28736962 | 3426 | |
0e5bf2a8 PA |
3427 | /* No interesting event to report to the core. */ |
3428 | ||
3429 | if (target_options & TARGET_WNOHANG) | |
3430 | { | |
01124a23 | 3431 | if (debug_linux_nat) |
28736962 PA |
3432 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3433 | ||
0e5bf2a8 | 3434 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3435 | restore_child_signals_mask (&prev_mask); |
3436 | return minus_one_ptid; | |
3437 | } | |
d6b0e80f AC |
3438 | |
3439 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3440 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3441 | |
3442 | /* Block until we get an event reported with SIGCHLD. */ | |
3443 | sigsuspend (&suspend_mask); | |
d6b0e80f AC |
3444 | } |
3445 | ||
b84876c2 | 3446 | if (!target_can_async_p ()) |
d26b5354 | 3447 | clear_sigint_trap (); |
d6b0e80f AC |
3448 | |
3449 | gdb_assert (lp); | |
3450 | ||
ca2163eb PA |
3451 | status = lp->status; |
3452 | lp->status = 0; | |
3453 | ||
d6b0e80f AC |
3454 | /* Don't report signals that GDB isn't interested in, such as |
3455 | signals that are neither printed nor stopped upon. Stopping all | |
3456 | threads can be a bit time-consuming so if we want decent | |
3457 | performance with heavily multi-threaded programs, especially when | |
3458 | they're using a high frequency timer, we'd better avoid it if we | |
3459 | can. */ | |
3460 | ||
3461 | if (WIFSTOPPED (status)) | |
3462 | { | |
2ea28649 | 3463 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); |
d6b0e80f | 3464 | |
2455069d UW |
3465 | /* When using hardware single-step, we need to report every signal. |
3466 | Otherwise, signals in pass_mask may be short-circuited. */ | |
d539ed7e | 3467 | if (!lp->step |
2455069d | 3468 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))) |
d6b0e80f AC |
3469 | { |
3470 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
3471 | here? It is not clear we should. GDB may not expect | |
3472 | other threads to run. On the other hand, not resuming | |
3473 | newly attached threads may cause an unwanted delay in | |
3474 | getting them running. */ | |
3475 | registers_changed (); | |
7b50312a PA |
3476 | if (linux_nat_prepare_to_resume != NULL) |
3477 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3478 | linux_ops->to_resume (linux_ops, |
3479 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
10d6c8cd | 3480 | lp->step, signo); |
d6b0e80f AC |
3481 | if (debug_linux_nat) |
3482 | fprintf_unfiltered (gdb_stdlog, | |
3483 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3484 | lp->step ? | |
3485 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3486 | target_pid_to_str (lp->ptid), | |
a493e3e2 | 3487 | (signo != GDB_SIGNAL_0 |
2ea28649 | 3488 | ? strsignal (gdb_signal_to_host (signo)) |
423ec54c | 3489 | : "0")); |
d6b0e80f | 3490 | lp->stopped = 0; |
d6b0e80f AC |
3491 | goto retry; |
3492 | } | |
3493 | ||
1ad15515 | 3494 | if (!non_stop) |
d6b0e80f | 3495 | { |
1ad15515 PA |
3496 | /* Only do the below in all-stop, as we currently use SIGINT |
3497 | to implement target_stop (see linux_nat_stop) in | |
3498 | non-stop. */ | |
a493e3e2 | 3499 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) |
1ad15515 PA |
3500 | { |
3501 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3502 | forwarded to the entire process group, that is, all LWPs | |
3503 | will receive it - unless they're using CLONE_THREAD to | |
3504 | share signals. Since we only want to report it once, we | |
3505 | mark it as ignored for all LWPs except this one. */ | |
d90e17a7 PA |
3506 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)), |
3507 | set_ignore_sigint, NULL); | |
1ad15515 PA |
3508 | lp->ignore_sigint = 0; |
3509 | } | |
3510 | else | |
3511 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
3512 | } |
3513 | } | |
3514 | ||
3515 | /* This LWP is stopped now. */ | |
3516 | lp->stopped = 1; | |
3517 | ||
3518 | if (debug_linux_nat) | |
3519 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
3520 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
3521 | ||
4c28f408 PA |
3522 | if (!non_stop) |
3523 | { | |
3524 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3525 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3526 | |
3527 | /* ... and wait until all of them have reported back that | |
3528 | they're no longer running. */ | |
d90e17a7 | 3529 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
4c28f408 PA |
3530 | |
3531 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3532 | from among those that have had events. Giving equal priority | |
3533 | to all LWPs that have had events helps prevent | |
3534 | starvation. */ | |
0e5bf2a8 | 3535 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d90e17a7 | 3536 | select_event_lwp (ptid, &lp, &status); |
d6b0e80f | 3537 | |
e3e9f5a2 PA |
3538 | /* Now that we've selected our final event LWP, cancel any |
3539 | breakpoints in other LWPs that have hit a GDB breakpoint. | |
3540 | See the comment in cancel_breakpoints_callback to find out | |
3541 | why. */ | |
3542 | iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp); | |
3543 | ||
4b60df3d PA |
3544 | /* We'll need this to determine whether to report a SIGSTOP as |
3545 | TARGET_WAITKIND_0. Need to take a copy because | |
3546 | resume_clear_callback clears it. */ | |
3547 | last_resume_kind = lp->last_resume_kind; | |
3548 | ||
e3e9f5a2 PA |
3549 | /* In all-stop, from the core's perspective, all LWPs are now |
3550 | stopped until a new resume action is sent over. */ | |
3551 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3552 | } | |
3553 | else | |
25289eb2 | 3554 | { |
4b60df3d PA |
3555 | /* See above. */ |
3556 | last_resume_kind = lp->last_resume_kind; | |
3557 | resume_clear_callback (lp, NULL); | |
25289eb2 | 3558 | } |
d6b0e80f | 3559 | |
26ab7092 | 3560 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3561 | { |
d6b0e80f AC |
3562 | if (debug_linux_nat) |
3563 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3564 | "LLW: trap ptid is %s.\n", |
3565 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3566 | } |
d6b0e80f AC |
3567 | |
3568 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3569 | { | |
3570 | *ourstatus = lp->waitstatus; | |
3571 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3572 | } | |
3573 | else | |
3574 | store_waitstatus (ourstatus, status); | |
3575 | ||
01124a23 | 3576 | if (debug_linux_nat) |
b84876c2 PA |
3577 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3578 | ||
7feb7d06 | 3579 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3580 | |
4b60df3d | 3581 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3582 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3583 | && WSTOPSIG (status) == SIGSTOP) | |
3584 | { | |
3585 | /* A thread that has been requested to stop by GDB with | |
3586 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3587 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3588 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3589 | } |
3590 | ||
1e225492 JK |
3591 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3592 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3593 | lp->core = -1; | |
3594 | else | |
2e794194 | 3595 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3596 | |
f973ed9c | 3597 | return lp->ptid; |
d6b0e80f AC |
3598 | } |
3599 | ||
e3e9f5a2 PA |
3600 | /* Resume LWPs that are currently stopped without any pending status |
3601 | to report, but are resumed from the core's perspective. */ | |
3602 | ||
3603 | static int | |
3604 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3605 | { | |
3606 | ptid_t *wait_ptid_p = data; | |
3607 | ||
3608 | if (lp->stopped | |
3609 | && lp->resumed | |
3610 | && lp->status == 0 | |
3611 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
3612 | { | |
336060f3 PA |
3613 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3614 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
3615 | CORE_ADDR pc = regcache_read_pc (regcache); | |
3616 | ||
e3e9f5a2 PA |
3617 | gdb_assert (is_executing (lp->ptid)); |
3618 | ||
3619 | /* Don't bother if there's a breakpoint at PC that we'd hit | |
3620 | immediately, and we're not waiting for this LWP. */ | |
3621 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3622 | { | |
e3e9f5a2 PA |
3623 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
3624 | return 0; | |
3625 | } | |
3626 | ||
3627 | if (debug_linux_nat) | |
3628 | fprintf_unfiltered (gdb_stdlog, | |
336060f3 PA |
3629 | "RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", |
3630 | target_pid_to_str (lp->ptid), | |
3631 | paddress (gdbarch, pc), | |
3632 | lp->step); | |
e3e9f5a2 | 3633 | |
336060f3 | 3634 | registers_changed (); |
7b50312a PA |
3635 | if (linux_nat_prepare_to_resume != NULL) |
3636 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3637 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3638 | lp->step, GDB_SIGNAL_0); |
e3e9f5a2 | 3639 | lp->stopped = 0; |
e3e9f5a2 PA |
3640 | lp->stopped_by_watchpoint = 0; |
3641 | } | |
3642 | ||
3643 | return 0; | |
3644 | } | |
3645 | ||
7feb7d06 PA |
3646 | static ptid_t |
3647 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3648 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3649 | int target_options) | |
7feb7d06 PA |
3650 | { |
3651 | ptid_t event_ptid; | |
3652 | ||
3653 | if (debug_linux_nat) | |
09826ec5 PA |
3654 | { |
3655 | char *options_string; | |
3656 | ||
3657 | options_string = target_options_to_string (target_options); | |
3658 | fprintf_unfiltered (gdb_stdlog, | |
3659 | "linux_nat_wait: [%s], [%s]\n", | |
3660 | target_pid_to_str (ptid), | |
3661 | options_string); | |
3662 | xfree (options_string); | |
3663 | } | |
7feb7d06 PA |
3664 | |
3665 | /* Flush the async file first. */ | |
3666 | if (target_can_async_p ()) | |
3667 | async_file_flush (); | |
3668 | ||
e3e9f5a2 PA |
3669 | /* Resume LWPs that are currently stopped without any pending status |
3670 | to report, but are resumed from the core's perspective. LWPs get | |
3671 | in this state if we find them stopping at a time we're not | |
3672 | interested in reporting the event (target_wait on a | |
3673 | specific_process, for example, see linux_nat_wait_1), and | |
3674 | meanwhile the event became uninteresting. Don't bother resuming | |
3675 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3676 | if (non_stop) | |
3677 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3678 | ||
47608cb1 | 3679 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3680 | |
3681 | /* If we requested any event, and something came out, assume there | |
3682 | may be more. If we requested a specific lwp or process, also | |
3683 | assume there may be more. */ | |
3684 | if (target_can_async_p () | |
6953d224 PA |
3685 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3686 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3687 | || !ptid_equal (ptid, minus_one_ptid))) |
3688 | async_file_mark (); | |
3689 | ||
3690 | /* Get ready for the next event. */ | |
3691 | if (target_can_async_p ()) | |
3692 | target_async (inferior_event_handler, 0); | |
3693 | ||
3694 | return event_ptid; | |
3695 | } | |
3696 | ||
d6b0e80f AC |
3697 | static int |
3698 | kill_callback (struct lwp_info *lp, void *data) | |
3699 | { | |
ed731959 JK |
3700 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3701 | ||
3702 | errno = 0; | |
dfd4cc63 | 3703 | kill (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 JK |
3704 | if (debug_linux_nat) |
3705 | fprintf_unfiltered (gdb_stdlog, | |
3706 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3707 | target_pid_to_str (lp->ptid), | |
3708 | errno ? safe_strerror (errno) : "OK"); | |
3709 | ||
3710 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3711 | ||
d6b0e80f | 3712 | errno = 0; |
dfd4cc63 | 3713 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f AC |
3714 | if (debug_linux_nat) |
3715 | fprintf_unfiltered (gdb_stdlog, | |
3716 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3717 | target_pid_to_str (lp->ptid), | |
3718 | errno ? safe_strerror (errno) : "OK"); | |
3719 | ||
3720 | return 0; | |
3721 | } | |
3722 | ||
3723 | static int | |
3724 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3725 | { | |
3726 | pid_t pid; | |
3727 | ||
3728 | /* We must make sure that there are no pending events (delayed | |
3729 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3730 | program doesn't interfere with any following debugging session. */ | |
3731 | ||
3732 | /* For cloned processes we must check both with __WCLONE and | |
3733 | without, since the exit status of a cloned process isn't reported | |
3734 | with __WCLONE. */ | |
3735 | if (lp->cloned) | |
3736 | { | |
3737 | do | |
3738 | { | |
dfd4cc63 | 3739 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3740 | if (pid != (pid_t) -1) |
d6b0e80f | 3741 | { |
e85a822c DJ |
3742 | if (debug_linux_nat) |
3743 | fprintf_unfiltered (gdb_stdlog, | |
3744 | "KWC: wait %s received unknown.\n", | |
3745 | target_pid_to_str (lp->ptid)); | |
3746 | /* The Linux kernel sometimes fails to kill a thread | |
3747 | completely after PTRACE_KILL; that goes from the stop | |
3748 | point in do_fork out to the one in | |
3749 | get_signal_to_deliever and waits again. So kill it | |
3750 | again. */ | |
3751 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3752 | } |
3753 | } | |
dfd4cc63 | 3754 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3755 | |
3756 | gdb_assert (pid == -1 && errno == ECHILD); | |
3757 | } | |
3758 | ||
3759 | do | |
3760 | { | |
dfd4cc63 | 3761 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3762 | if (pid != (pid_t) -1) |
d6b0e80f | 3763 | { |
e85a822c DJ |
3764 | if (debug_linux_nat) |
3765 | fprintf_unfiltered (gdb_stdlog, | |
3766 | "KWC: wait %s received unk.\n", | |
3767 | target_pid_to_str (lp->ptid)); | |
3768 | /* See the call to kill_callback above. */ | |
3769 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3770 | } |
3771 | } | |
dfd4cc63 | 3772 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3773 | |
3774 | gdb_assert (pid == -1 && errno == ECHILD); | |
3775 | return 0; | |
3776 | } | |
3777 | ||
3778 | static void | |
7d85a9c0 | 3779 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3780 | { |
f973ed9c DJ |
3781 | struct target_waitstatus last; |
3782 | ptid_t last_ptid; | |
3783 | int status; | |
d6b0e80f | 3784 | |
f973ed9c DJ |
3785 | /* If we're stopped while forking and we haven't followed yet, |
3786 | kill the other task. We need to do this first because the | |
3787 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3788 | |
f973ed9c | 3789 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3790 | |
f973ed9c DJ |
3791 | if (last.kind == TARGET_WAITKIND_FORKED |
3792 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3793 | { | |
dfd4cc63 | 3794 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3795 | wait (&status); |
26cb8b7c PA |
3796 | |
3797 | /* Let the arch-specific native code know this process is | |
3798 | gone. */ | |
dfd4cc63 | 3799 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3800 | } |
3801 | ||
3802 | if (forks_exist_p ()) | |
7feb7d06 | 3803 | linux_fork_killall (); |
f973ed9c DJ |
3804 | else |
3805 | { | |
d90e17a7 | 3806 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3807 | |
4c28f408 PA |
3808 | /* Stop all threads before killing them, since ptrace requires |
3809 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3810 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3811 | /* ... and wait until all of them have reported back that |
3812 | they're no longer running. */ | |
d90e17a7 | 3813 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3814 | |
f973ed9c | 3815 | /* Kill all LWP's ... */ |
d90e17a7 | 3816 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3817 | |
3818 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3819 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3820 | } |
3821 | ||
3822 | target_mourn_inferior (); | |
d6b0e80f AC |
3823 | } |
3824 | ||
3825 | static void | |
136d6dae | 3826 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3827 | { |
26cb8b7c PA |
3828 | int pid = ptid_get_pid (inferior_ptid); |
3829 | ||
3830 | purge_lwp_list (pid); | |
d6b0e80f | 3831 | |
f973ed9c | 3832 | if (! forks_exist_p ()) |
d90e17a7 PA |
3833 | /* Normal case, no other forks available. */ |
3834 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3835 | else |
3836 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3837 | there are other viable forks to debug. Delete the exiting | |
3838 | one and context-switch to the first available. */ | |
3839 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3840 | |
3841 | /* Let the arch-specific native code know this process is gone. */ | |
3842 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3843 | } |
3844 | ||
5b009018 PA |
3845 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3846 | layout of the inferiors' architecture. */ | |
3847 | ||
3848 | static void | |
a5362b9a | 3849 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3850 | { |
3851 | int done = 0; | |
3852 | ||
3853 | if (linux_nat_siginfo_fixup != NULL) | |
3854 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3855 | ||
3856 | /* If there was no callback, or the callback didn't do anything, | |
3857 | then just do a straight memcpy. */ | |
3858 | if (!done) | |
3859 | { | |
3860 | if (direction == 1) | |
a5362b9a | 3861 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3862 | else |
a5362b9a | 3863 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3864 | } |
3865 | } | |
3866 | ||
4aa995e1 PA |
3867 | static LONGEST |
3868 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, | |
3869 | const char *annex, gdb_byte *readbuf, | |
3870 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
3871 | { | |
4aa995e1 | 3872 | int pid; |
a5362b9a TS |
3873 | siginfo_t siginfo; |
3874 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3875 | |
3876 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3877 | gdb_assert (readbuf || writebuf); | |
3878 | ||
dfd4cc63 | 3879 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3880 | if (pid == 0) |
dfd4cc63 | 3881 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3882 | |
3883 | if (offset > sizeof (siginfo)) | |
3884 | return -1; | |
3885 | ||
3886 | errno = 0; | |
3887 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3888 | if (errno != 0) | |
3889 | return -1; | |
3890 | ||
5b009018 PA |
3891 | /* When GDB is built as a 64-bit application, ptrace writes into |
3892 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3893 | inferior with a 64-bit GDB should look the same as debugging it | |
3894 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3895 | the converted layout, so any read/write will have to be done | |
3896 | post-conversion. */ | |
3897 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3898 | ||
4aa995e1 PA |
3899 | if (offset + len > sizeof (siginfo)) |
3900 | len = sizeof (siginfo) - offset; | |
3901 | ||
3902 | if (readbuf != NULL) | |
5b009018 | 3903 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3904 | else |
3905 | { | |
5b009018 PA |
3906 | memcpy (inf_siginfo + offset, writebuf, len); |
3907 | ||
3908 | /* Convert back to ptrace layout before flushing it out. */ | |
3909 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3910 | ||
4aa995e1 PA |
3911 | errno = 0; |
3912 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3913 | if (errno != 0) | |
3914 | return -1; | |
3915 | } | |
3916 | ||
3917 | return len; | |
3918 | } | |
3919 | ||
10d6c8cd DJ |
3920 | static LONGEST |
3921 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, | |
3922 | const char *annex, gdb_byte *readbuf, | |
3923 | const gdb_byte *writebuf, | |
3924 | ULONGEST offset, LONGEST len) | |
d6b0e80f | 3925 | { |
4aa995e1 | 3926 | struct cleanup *old_chain; |
10d6c8cd | 3927 | LONGEST xfer; |
d6b0e80f | 3928 | |
4aa995e1 PA |
3929 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3930 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
3931 | offset, len); | |
3932 | ||
c35b1492 PA |
3933 | /* The target is connected but no live inferior is selected. Pass |
3934 | this request down to a lower stratum (e.g., the executable | |
3935 | file). */ | |
3936 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
3937 | return 0; | |
3938 | ||
4aa995e1 PA |
3939 | old_chain = save_inferior_ptid (); |
3940 | ||
dfd4cc63 LM |
3941 | if (ptid_lwp_p (inferior_ptid)) |
3942 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3943 | |
10d6c8cd DJ |
3944 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
3945 | offset, len); | |
d6b0e80f AC |
3946 | |
3947 | do_cleanups (old_chain); | |
3948 | return xfer; | |
3949 | } | |
3950 | ||
3951 | static int | |
28439f5e | 3952 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3953 | { |
8c6a60d1 | 3954 | int err, tmp_errno; |
4c28f408 | 3955 | |
dfd4cc63 | 3956 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3957 | |
4c28f408 PA |
3958 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3959 | running thread errors out claiming that the thread doesn't | |
3960 | exist. */ | |
dfd4cc63 | 3961 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3962 | tmp_errno = errno; |
d6b0e80f AC |
3963 | if (debug_linux_nat) |
3964 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3965 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3966 | target_pid_to_str (ptid), |
8c6a60d1 | 3967 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3968 | |
4c28f408 | 3969 | if (err != 0) |
d6b0e80f AC |
3970 | return 0; |
3971 | ||
3972 | return 1; | |
3973 | } | |
3974 | ||
28439f5e PA |
3975 | static int |
3976 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3977 | { | |
3978 | return linux_thread_alive (ptid); | |
3979 | } | |
3980 | ||
d6b0e80f | 3981 | static char * |
117de6a9 | 3982 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3983 | { |
3984 | static char buf[64]; | |
3985 | ||
dfd4cc63 LM |
3986 | if (ptid_lwp_p (ptid) |
3987 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
3988 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 3989 | { |
dfd4cc63 | 3990 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
3991 | return buf; |
3992 | } | |
3993 | ||
3994 | return normal_pid_to_str (ptid); | |
3995 | } | |
3996 | ||
4694da01 TT |
3997 | static char * |
3998 | linux_nat_thread_name (struct thread_info *thr) | |
3999 | { | |
4000 | int pid = ptid_get_pid (thr->ptid); | |
4001 | long lwp = ptid_get_lwp (thr->ptid); | |
4002 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4003 | char buf[sizeof (FORMAT) + 30]; | |
4004 | FILE *comm_file; | |
4005 | char *result = NULL; | |
4006 | ||
4007 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4008 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4009 | if (comm_file) |
4010 | { | |
4011 | /* Not exported by the kernel, so we define it here. */ | |
4012 | #define COMM_LEN 16 | |
4013 | static char line[COMM_LEN + 1]; | |
4014 | ||
4015 | if (fgets (line, sizeof (line), comm_file)) | |
4016 | { | |
4017 | char *nl = strchr (line, '\n'); | |
4018 | ||
4019 | if (nl) | |
4020 | *nl = '\0'; | |
4021 | if (*line != '\0') | |
4022 | result = line; | |
4023 | } | |
4024 | ||
4025 | fclose (comm_file); | |
4026 | } | |
4027 | ||
4028 | #undef COMM_LEN | |
4029 | #undef FORMAT | |
4030 | ||
4031 | return result; | |
4032 | } | |
4033 | ||
dba24537 AC |
4034 | /* Accepts an integer PID; Returns a string representing a file that |
4035 | can be opened to get the symbols for the child process. */ | |
4036 | ||
6d8fd2b7 UW |
4037 | static char * |
4038 | linux_child_pid_to_exec_file (int pid) | |
dba24537 AC |
4039 | { |
4040 | char *name1, *name2; | |
4041 | ||
d8d2a3ee PA |
4042 | name1 = xmalloc (PATH_MAX); |
4043 | name2 = xmalloc (PATH_MAX); | |
dba24537 AC |
4044 | make_cleanup (xfree, name1); |
4045 | make_cleanup (xfree, name2); | |
d8d2a3ee | 4046 | memset (name2, 0, PATH_MAX); |
dba24537 | 4047 | |
cde33bf1 | 4048 | xsnprintf (name1, PATH_MAX, "/proc/%d/exe", pid); |
d8d2a3ee | 4049 | if (readlink (name1, name2, PATH_MAX - 1) > 0) |
dba24537 AC |
4050 | return name2; |
4051 | else | |
4052 | return name1; | |
4053 | } | |
4054 | ||
dba24537 AC |
4055 | /* Records the thread's register state for the corefile note |
4056 | section. */ | |
4057 | ||
4058 | static char * | |
6432734d UW |
4059 | linux_nat_collect_thread_registers (const struct regcache *regcache, |
4060 | ptid_t ptid, bfd *obfd, | |
4061 | char *note_data, int *note_size, | |
2ea28649 | 4062 | enum gdb_signal stop_signal) |
dba24537 | 4063 | { |
6432734d | 4064 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
4f844a66 | 4065 | const struct regset *regset; |
55e969c1 | 4066 | int core_regset_p; |
6432734d UW |
4067 | gdb_gregset_t gregs; |
4068 | gdb_fpregset_t fpregs; | |
4f844a66 DM |
4069 | |
4070 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
dba24537 | 4071 | |
6432734d UW |
4072 | if (core_regset_p |
4073 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
4074 | sizeof (gregs))) | |
4075 | != NULL && regset->collect_regset != NULL) | |
4076 | regset->collect_regset (regset, regcache, -1, &gregs, sizeof (gregs)); | |
4f844a66 | 4077 | else |
6432734d | 4078 | fill_gregset (regcache, &gregs, -1); |
2f2241f1 | 4079 | |
6432734d UW |
4080 | note_data = (char *) elfcore_write_prstatus |
4081 | (obfd, note_data, note_size, ptid_get_lwp (ptid), | |
2ea28649 | 4082 | gdb_signal_to_host (stop_signal), &gregs); |
2f2241f1 | 4083 | |
6432734d UW |
4084 | if (core_regset_p |
4085 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
4086 | sizeof (fpregs))) | |
3e43a32a | 4087 | != NULL && regset->collect_regset != NULL) |
6432734d UW |
4088 | regset->collect_regset (regset, regcache, -1, &fpregs, sizeof (fpregs)); |
4089 | else | |
4090 | fill_fpregset (regcache, &fpregs, -1); | |
17ea7499 | 4091 | |
6432734d UW |
4092 | note_data = (char *) elfcore_write_prfpreg (obfd, note_data, note_size, |
4093 | &fpregs, sizeof (fpregs)); | |
4f844a66 | 4094 | |
dba24537 AC |
4095 | return note_data; |
4096 | } | |
4097 | ||
dba24537 AC |
4098 | /* Fills the "to_make_corefile_note" target vector. Builds the note |
4099 | section for a corefile, and returns it in a malloc buffer. */ | |
4100 | ||
4101 | static char * | |
4102 | linux_nat_make_corefile_notes (bfd *obfd, int *note_size) | |
4103 | { | |
6432734d UW |
4104 | /* FIXME: uweigand/2011-10-06: Once all GNU/Linux architectures have been |
4105 | converted to gdbarch_core_regset_sections, this function can go away. */ | |
f5656ead | 4106 | return linux_make_corefile_notes (target_gdbarch (), obfd, note_size, |
6432734d | 4107 | linux_nat_collect_thread_registers); |
dba24537 AC |
4108 | } |
4109 | ||
10d6c8cd DJ |
4110 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4111 | filesystem. Because we can use a single read() call for /proc, this | |
4112 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4113 | but it doesn't support writes. */ | |
4114 | ||
4115 | static LONGEST | |
4116 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, | |
4117 | const char *annex, gdb_byte *readbuf, | |
4118 | const gdb_byte *writebuf, | |
4119 | ULONGEST offset, LONGEST len) | |
dba24537 | 4120 | { |
10d6c8cd DJ |
4121 | LONGEST ret; |
4122 | int fd; | |
dba24537 AC |
4123 | char filename[64]; |
4124 | ||
10d6c8cd | 4125 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4126 | return 0; |
4127 | ||
4128 | /* Don't bother for one word. */ | |
4129 | if (len < 3 * sizeof (long)) | |
4130 | return 0; | |
4131 | ||
4132 | /* We could keep this file open and cache it - possibly one per | |
4133 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4134 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4135 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4136 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 AC |
4137 | if (fd == -1) |
4138 | return 0; | |
4139 | ||
4140 | /* If pread64 is available, use it. It's faster if the kernel | |
4141 | supports it (only one syscall), and it's 64-bit safe even on | |
4142 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4143 | application). */ | |
4144 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4145 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4146 | #else |
10d6c8cd | 4147 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4148 | #endif |
4149 | ret = 0; | |
4150 | else | |
4151 | ret = len; | |
4152 | ||
4153 | close (fd); | |
4154 | return ret; | |
4155 | } | |
4156 | ||
efcbbd14 UW |
4157 | |
4158 | /* Enumerate spufs IDs for process PID. */ | |
4159 | static LONGEST | |
4160 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, LONGEST len) | |
4161 | { | |
f5656ead | 4162 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4163 | LONGEST pos = 0; |
4164 | LONGEST written = 0; | |
4165 | char path[128]; | |
4166 | DIR *dir; | |
4167 | struct dirent *entry; | |
4168 | ||
4169 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4170 | dir = opendir (path); | |
4171 | if (!dir) | |
4172 | return -1; | |
4173 | ||
4174 | rewinddir (dir); | |
4175 | while ((entry = readdir (dir)) != NULL) | |
4176 | { | |
4177 | struct stat st; | |
4178 | struct statfs stfs; | |
4179 | int fd; | |
4180 | ||
4181 | fd = atoi (entry->d_name); | |
4182 | if (!fd) | |
4183 | continue; | |
4184 | ||
4185 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4186 | if (stat (path, &st) != 0) | |
4187 | continue; | |
4188 | if (!S_ISDIR (st.st_mode)) | |
4189 | continue; | |
4190 | ||
4191 | if (statfs (path, &stfs) != 0) | |
4192 | continue; | |
4193 | if (stfs.f_type != SPUFS_MAGIC) | |
4194 | continue; | |
4195 | ||
4196 | if (pos >= offset && pos + 4 <= offset + len) | |
4197 | { | |
4198 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4199 | written += 4; | |
4200 | } | |
4201 | pos += 4; | |
4202 | } | |
4203 | ||
4204 | closedir (dir); | |
4205 | return written; | |
4206 | } | |
4207 | ||
4208 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4209 | object type, using the /proc file system. */ | |
4210 | static LONGEST | |
4211 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, | |
4212 | const char *annex, gdb_byte *readbuf, | |
4213 | const gdb_byte *writebuf, | |
4214 | ULONGEST offset, LONGEST len) | |
4215 | { | |
4216 | char buf[128]; | |
4217 | int fd = 0; | |
4218 | int ret = -1; | |
dfd4cc63 | 4219 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4220 | |
4221 | if (!annex) | |
4222 | { | |
4223 | if (!readbuf) | |
4224 | return -1; | |
4225 | else | |
4226 | return spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4227 | } | |
4228 | ||
4229 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4230 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 UW |
4231 | if (fd <= 0) |
4232 | return -1; | |
4233 | ||
4234 | if (offset != 0 | |
4235 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4236 | { | |
4237 | close (fd); | |
4238 | return 0; | |
4239 | } | |
4240 | ||
4241 | if (writebuf) | |
4242 | ret = write (fd, writebuf, (size_t) len); | |
4243 | else if (readbuf) | |
4244 | ret = read (fd, readbuf, (size_t) len); | |
4245 | ||
4246 | close (fd); | |
4247 | return ret; | |
4248 | } | |
4249 | ||
4250 | ||
dba24537 AC |
4251 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4252 | ||
4253 | static void | |
4254 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4255 | { | |
4256 | int len = strlen (line) - 1; | |
4257 | const char *p; | |
4258 | int signum; | |
4259 | ||
4260 | if (line[len] != '\n') | |
8a3fe4f8 | 4261 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4262 | |
4263 | p = line; | |
4264 | signum = len * 4; | |
4265 | while (len-- > 0) | |
4266 | { | |
4267 | int digit; | |
4268 | ||
4269 | if (*p >= '0' && *p <= '9') | |
4270 | digit = *p - '0'; | |
4271 | else if (*p >= 'a' && *p <= 'f') | |
4272 | digit = *p - 'a' + 10; | |
4273 | else | |
8a3fe4f8 | 4274 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4275 | |
4276 | signum -= 4; | |
4277 | ||
4278 | if (digit & 1) | |
4279 | sigaddset (sigs, signum + 1); | |
4280 | if (digit & 2) | |
4281 | sigaddset (sigs, signum + 2); | |
4282 | if (digit & 4) | |
4283 | sigaddset (sigs, signum + 3); | |
4284 | if (digit & 8) | |
4285 | sigaddset (sigs, signum + 4); | |
4286 | ||
4287 | p++; | |
4288 | } | |
4289 | } | |
4290 | ||
4291 | /* Find process PID's pending signals from /proc/pid/status and set | |
4292 | SIGS to match. */ | |
4293 | ||
4294 | void | |
3e43a32a MS |
4295 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4296 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4297 | { |
4298 | FILE *procfile; | |
d8d2a3ee | 4299 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4300 | struct cleanup *cleanup; |
dba24537 AC |
4301 | |
4302 | sigemptyset (pending); | |
4303 | sigemptyset (blocked); | |
4304 | sigemptyset (ignored); | |
cde33bf1 | 4305 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4306 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4307 | if (procfile == NULL) |
8a3fe4f8 | 4308 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4309 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4310 | |
d8d2a3ee | 4311 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4312 | { |
4313 | /* Normal queued signals are on the SigPnd line in the status | |
4314 | file. However, 2.6 kernels also have a "shared" pending | |
4315 | queue for delivering signals to a thread group, so check for | |
4316 | a ShdPnd line also. | |
4317 | ||
4318 | Unfortunately some Red Hat kernels include the shared pending | |
4319 | queue but not the ShdPnd status field. */ | |
4320 | ||
4321 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
4322 | add_line_to_sigset (buffer + 8, pending); | |
4323 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
4324 | add_line_to_sigset (buffer + 8, pending); | |
4325 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
4326 | add_line_to_sigset (buffer + 8, blocked); | |
4327 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
4328 | add_line_to_sigset (buffer + 8, ignored); | |
4329 | } | |
4330 | ||
7c8a8b04 | 4331 | do_cleanups (cleanup); |
dba24537 AC |
4332 | } |
4333 | ||
07e059b5 VP |
4334 | static LONGEST |
4335 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, | |
e0881a8e MS |
4336 | const char *annex, gdb_byte *readbuf, |
4337 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
07e059b5 | 4338 | { |
07e059b5 VP |
4339 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4340 | ||
d26e3629 | 4341 | return linux_common_xfer_osdata (annex, readbuf, offset, len); |
07e059b5 VP |
4342 | } |
4343 | ||
10d6c8cd DJ |
4344 | static LONGEST |
4345 | linux_xfer_partial (struct target_ops *ops, enum target_object object, | |
4346 | const char *annex, gdb_byte *readbuf, | |
4347 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
4348 | { | |
4349 | LONGEST xfer; | |
4350 | ||
4351 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4352 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
10d6c8cd DJ |
4353 | offset, len); |
4354 | ||
07e059b5 VP |
4355 | if (object == TARGET_OBJECT_OSDATA) |
4356 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
4357 | offset, len); | |
4358 | ||
efcbbd14 UW |
4359 | if (object == TARGET_OBJECT_SPU) |
4360 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
4361 | offset, len); | |
4362 | ||
8f313923 JK |
4363 | /* GDB calculates all the addresses in possibly larget width of the address. |
4364 | Address width needs to be masked before its final use - either by | |
4365 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4366 | ||
4367 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4368 | ||
4369 | if (object == TARGET_OBJECT_MEMORY) | |
4370 | { | |
f5656ead | 4371 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4372 | |
4373 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4374 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4375 | } | |
4376 | ||
10d6c8cd DJ |
4377 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
4378 | offset, len); | |
4379 | if (xfer != 0) | |
4380 | return xfer; | |
4381 | ||
4382 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
4383 | offset, len); | |
4384 | } | |
4385 | ||
5808517f YQ |
4386 | static void |
4387 | cleanup_target_stop (void *arg) | |
4388 | { | |
4389 | ptid_t *ptid = (ptid_t *) arg; | |
4390 | ||
4391 | gdb_assert (arg != NULL); | |
4392 | ||
4393 | /* Unpause all */ | |
a493e3e2 | 4394 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4395 | } |
4396 | ||
4397 | static VEC(static_tracepoint_marker_p) * | |
4398 | linux_child_static_tracepoint_markers_by_strid (const char *strid) | |
4399 | { | |
4400 | char s[IPA_CMD_BUF_SIZE]; | |
4401 | struct cleanup *old_chain; | |
4402 | int pid = ptid_get_pid (inferior_ptid); | |
4403 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4404 | struct static_tracepoint_marker *marker = NULL; | |
4405 | char *p = s; | |
4406 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4407 | ||
4408 | /* Pause all */ | |
4409 | target_stop (ptid); | |
4410 | ||
4411 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4412 | s[sizeof ("qTfSTM")] = 0; | |
4413 | ||
42476b70 | 4414 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4415 | |
4416 | old_chain = make_cleanup (free_current_marker, &marker); | |
4417 | make_cleanup (cleanup_target_stop, &ptid); | |
4418 | ||
4419 | while (*p++ == 'm') | |
4420 | { | |
4421 | if (marker == NULL) | |
4422 | marker = XCNEW (struct static_tracepoint_marker); | |
4423 | ||
4424 | do | |
4425 | { | |
4426 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4427 | ||
4428 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4429 | { | |
4430 | VEC_safe_push (static_tracepoint_marker_p, | |
4431 | markers, marker); | |
4432 | marker = NULL; | |
4433 | } | |
4434 | else | |
4435 | { | |
4436 | release_static_tracepoint_marker (marker); | |
4437 | memset (marker, 0, sizeof (*marker)); | |
4438 | } | |
4439 | } | |
4440 | while (*p++ == ','); /* comma-separated list */ | |
4441 | ||
4442 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4443 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4444 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4445 | p = s; |
4446 | } | |
4447 | ||
4448 | do_cleanups (old_chain); | |
4449 | ||
4450 | return markers; | |
4451 | } | |
4452 | ||
e9efe249 | 4453 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4454 | it with local methods. */ |
4455 | ||
910122bf UW |
4456 | static void |
4457 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4458 | { |
6d8fd2b7 | 4459 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4460 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4461 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4462 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4463 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4464 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4465 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4466 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4467 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4468 | t->to_post_attach = linux_child_post_attach; |
4469 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4470 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; |
4471 | ||
4472 | super_xfer_partial = t->to_xfer_partial; | |
4473 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4474 | |
4475 | t->to_static_tracepoint_markers_by_strid | |
4476 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4477 | } |
4478 | ||
4479 | struct target_ops * | |
4480 | linux_target (void) | |
4481 | { | |
4482 | struct target_ops *t; | |
4483 | ||
4484 | t = inf_ptrace_target (); | |
4485 | linux_target_install_ops (t); | |
4486 | ||
4487 | return t; | |
4488 | } | |
4489 | ||
4490 | struct target_ops * | |
7714d83a | 4491 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4492 | { |
4493 | struct target_ops *t; | |
4494 | ||
4495 | t = inf_ptrace_trad_target (register_u_offset); | |
4496 | linux_target_install_ops (t); | |
10d6c8cd | 4497 | |
10d6c8cd DJ |
4498 | return t; |
4499 | } | |
4500 | ||
b84876c2 PA |
4501 | /* target_is_async_p implementation. */ |
4502 | ||
4503 | static int | |
4504 | linux_nat_is_async_p (void) | |
4505 | { | |
4506 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4507 | it explicitly with the "set target-async" command. |
b84876c2 | 4508 | Someday, linux will always be async. */ |
3dd5b83d | 4509 | return target_async_permitted; |
b84876c2 PA |
4510 | } |
4511 | ||
4512 | /* target_can_async_p implementation. */ | |
4513 | ||
4514 | static int | |
4515 | linux_nat_can_async_p (void) | |
4516 | { | |
4517 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4518 | it explicitly with the "set target-async" command. |
b84876c2 | 4519 | Someday, linux will always be async. */ |
3dd5b83d | 4520 | return target_async_permitted; |
b84876c2 PA |
4521 | } |
4522 | ||
9908b566 VP |
4523 | static int |
4524 | linux_nat_supports_non_stop (void) | |
4525 | { | |
4526 | return 1; | |
4527 | } | |
4528 | ||
d90e17a7 PA |
4529 | /* True if we want to support multi-process. To be removed when GDB |
4530 | supports multi-exec. */ | |
4531 | ||
2277426b | 4532 | int linux_multi_process = 1; |
d90e17a7 PA |
4533 | |
4534 | static int | |
4535 | linux_nat_supports_multi_process (void) | |
4536 | { | |
4537 | return linux_multi_process; | |
4538 | } | |
4539 | ||
03583c20 UW |
4540 | static int |
4541 | linux_nat_supports_disable_randomization (void) | |
4542 | { | |
4543 | #ifdef HAVE_PERSONALITY | |
4544 | return 1; | |
4545 | #else | |
4546 | return 0; | |
4547 | #endif | |
4548 | } | |
4549 | ||
b84876c2 PA |
4550 | static int async_terminal_is_ours = 1; |
4551 | ||
4552 | /* target_terminal_inferior implementation. */ | |
4553 | ||
4554 | static void | |
4555 | linux_nat_terminal_inferior (void) | |
4556 | { | |
4557 | if (!target_is_async_p ()) | |
4558 | { | |
4559 | /* Async mode is disabled. */ | |
4560 | terminal_inferior (); | |
4561 | return; | |
4562 | } | |
4563 | ||
b84876c2 PA |
4564 | terminal_inferior (); |
4565 | ||
d9d2d8b6 | 4566 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4567 | if (!async_terminal_is_ours) |
4568 | return; | |
4569 | ||
4570 | delete_file_handler (input_fd); | |
4571 | async_terminal_is_ours = 0; | |
4572 | set_sigint_trap (); | |
4573 | } | |
4574 | ||
4575 | /* target_terminal_ours implementation. */ | |
4576 | ||
2c0b251b | 4577 | static void |
b84876c2 PA |
4578 | linux_nat_terminal_ours (void) |
4579 | { | |
4580 | if (!target_is_async_p ()) | |
4581 | { | |
4582 | /* Async mode is disabled. */ | |
4583 | terminal_ours (); | |
4584 | return; | |
4585 | } | |
4586 | ||
4587 | /* GDB should never give the terminal to the inferior if the | |
4588 | inferior is running in the background (run&, continue&, etc.), | |
4589 | but claiming it sure should. */ | |
4590 | terminal_ours (); | |
4591 | ||
b84876c2 PA |
4592 | if (async_terminal_is_ours) |
4593 | return; | |
4594 | ||
4595 | clear_sigint_trap (); | |
4596 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4597 | async_terminal_is_ours = 1; | |
4598 | } | |
4599 | ||
4600 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4601 | void *context); | |
4602 | static void *async_client_context; | |
4603 | ||
7feb7d06 PA |
4604 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4605 | so we notice when any child changes state, and notify the | |
4606 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4607 | above to wait for the arrival of a SIGCHLD. */ | |
4608 | ||
b84876c2 | 4609 | static void |
7feb7d06 | 4610 | sigchld_handler (int signo) |
b84876c2 | 4611 | { |
7feb7d06 PA |
4612 | int old_errno = errno; |
4613 | ||
01124a23 DE |
4614 | if (debug_linux_nat) |
4615 | ui_file_write_async_safe (gdb_stdlog, | |
4616 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4617 | |
4618 | if (signo == SIGCHLD | |
4619 | && linux_nat_event_pipe[0] != -1) | |
4620 | async_file_mark (); /* Let the event loop know that there are | |
4621 | events to handle. */ | |
4622 | ||
4623 | errno = old_errno; | |
4624 | } | |
4625 | ||
4626 | /* Callback registered with the target events file descriptor. */ | |
4627 | ||
4628 | static void | |
4629 | handle_target_event (int error, gdb_client_data client_data) | |
4630 | { | |
4631 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4632 | } | |
4633 | ||
4634 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4635 | ||
4636 | static int | |
4637 | linux_async_pipe (int enable) | |
4638 | { | |
4639 | int previous = (linux_nat_event_pipe[0] != -1); | |
4640 | ||
4641 | if (previous != enable) | |
4642 | { | |
4643 | sigset_t prev_mask; | |
4644 | ||
12696c10 PA |
4645 | /* Block child signals while we create/destroy the pipe, as |
4646 | their handler writes to it. */ | |
7feb7d06 PA |
4647 | block_child_signals (&prev_mask); |
4648 | ||
4649 | if (enable) | |
4650 | { | |
614c279d | 4651 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4652 | internal_error (__FILE__, __LINE__, |
4653 | "creating event pipe failed."); | |
4654 | ||
4655 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4656 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4657 | } | |
4658 | else | |
4659 | { | |
4660 | close (linux_nat_event_pipe[0]); | |
4661 | close (linux_nat_event_pipe[1]); | |
4662 | linux_nat_event_pipe[0] = -1; | |
4663 | linux_nat_event_pipe[1] = -1; | |
4664 | } | |
4665 | ||
4666 | restore_child_signals_mask (&prev_mask); | |
4667 | } | |
4668 | ||
4669 | return previous; | |
b84876c2 PA |
4670 | } |
4671 | ||
4672 | /* target_async implementation. */ | |
4673 | ||
4674 | static void | |
4675 | linux_nat_async (void (*callback) (enum inferior_event_type event_type, | |
4676 | void *context), void *context) | |
4677 | { | |
b84876c2 PA |
4678 | if (callback != NULL) |
4679 | { | |
4680 | async_client_callback = callback; | |
4681 | async_client_context = context; | |
7feb7d06 PA |
4682 | if (!linux_async_pipe (1)) |
4683 | { | |
4684 | add_file_handler (linux_nat_event_pipe[0], | |
4685 | handle_target_event, NULL); | |
4686 | /* There may be pending events to handle. Tell the event loop | |
4687 | to poll them. */ | |
4688 | async_file_mark (); | |
4689 | } | |
b84876c2 PA |
4690 | } |
4691 | else | |
4692 | { | |
4693 | async_client_callback = callback; | |
4694 | async_client_context = context; | |
b84876c2 | 4695 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4696 | linux_async_pipe (0); |
b84876c2 PA |
4697 | } |
4698 | return; | |
4699 | } | |
4700 | ||
a493e3e2 | 4701 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4702 | event came out. */ |
4703 | ||
4c28f408 | 4704 | static int |
252fbfc8 | 4705 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4706 | { |
d90e17a7 | 4707 | if (!lwp->stopped) |
252fbfc8 | 4708 | { |
d90e17a7 PA |
4709 | if (debug_linux_nat) |
4710 | fprintf_unfiltered (gdb_stdlog, | |
4711 | "LNSL: running -> suspending %s\n", | |
4712 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4713 | |
252fbfc8 | 4714 | |
25289eb2 PA |
4715 | if (lwp->last_resume_kind == resume_stop) |
4716 | { | |
4717 | if (debug_linux_nat) | |
4718 | fprintf_unfiltered (gdb_stdlog, | |
4719 | "linux-nat: already stopping LWP %ld at " | |
4720 | "GDB's request\n", | |
4721 | ptid_get_lwp (lwp->ptid)); | |
4722 | return 0; | |
4723 | } | |
252fbfc8 | 4724 | |
25289eb2 PA |
4725 | stop_callback (lwp, NULL); |
4726 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4727 | } |
4728 | else | |
4729 | { | |
4730 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4731 | |
d90e17a7 PA |
4732 | if (debug_linux_nat) |
4733 | { | |
e09875d4 | 4734 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4735 | fprintf_unfiltered (gdb_stdlog, |
4736 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4737 | target_pid_to_str (lwp->ptid)); |
4738 | else | |
3e43a32a MS |
4739 | fprintf_unfiltered (gdb_stdlog, |
4740 | "LNSL: already stopped/no " | |
4741 | "stop_requested yet %s\n", | |
d90e17a7 | 4742 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4743 | } |
4744 | } | |
4c28f408 PA |
4745 | return 0; |
4746 | } | |
4747 | ||
4748 | static void | |
4749 | linux_nat_stop (ptid_t ptid) | |
4750 | { | |
4751 | if (non_stop) | |
d90e17a7 | 4752 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 PA |
4753 | else |
4754 | linux_ops->to_stop (ptid); | |
4755 | } | |
4756 | ||
d90e17a7 | 4757 | static void |
460014f5 | 4758 | linux_nat_close (void) |
d90e17a7 PA |
4759 | { |
4760 | /* Unregister from the event loop. */ | |
305436e0 PA |
4761 | if (linux_nat_is_async_p ()) |
4762 | linux_nat_async (NULL, 0); | |
d90e17a7 | 4763 | |
d90e17a7 | 4764 | if (linux_ops->to_close) |
460014f5 | 4765 | linux_ops->to_close (); |
d90e17a7 PA |
4766 | } |
4767 | ||
c0694254 PA |
4768 | /* When requests are passed down from the linux-nat layer to the |
4769 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4770 | used. The address space pointer is stored in the inferior object, | |
4771 | but the common code that is passed such ptid can't tell whether | |
4772 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4773 | look up the "main" process id from the lwp here. */ | |
4774 | ||
70221824 | 4775 | static struct address_space * |
c0694254 PA |
4776 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4777 | { | |
4778 | struct lwp_info *lwp; | |
4779 | struct inferior *inf; | |
4780 | int pid; | |
4781 | ||
dfd4cc63 LM |
4782 | pid = ptid_get_lwp (ptid); |
4783 | if (ptid_get_lwp (ptid) == 0) | |
c0694254 PA |
4784 | { |
4785 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4786 | tgid. */ | |
4787 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4788 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4789 | } |
4790 | else | |
4791 | { | |
4792 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4793 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4794 | } |
4795 | ||
4796 | inf = find_inferior_pid (pid); | |
4797 | gdb_assert (inf != NULL); | |
4798 | return inf->aspace; | |
4799 | } | |
4800 | ||
dc146f7c VP |
4801 | /* Return the cached value of the processor core for thread PTID. */ |
4802 | ||
70221824 | 4803 | static int |
dc146f7c VP |
4804 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4805 | { | |
4806 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4807 | |
dc146f7c VP |
4808 | if (info) |
4809 | return info->core; | |
4810 | return -1; | |
4811 | } | |
4812 | ||
f973ed9c DJ |
4813 | void |
4814 | linux_nat_add_target (struct target_ops *t) | |
4815 | { | |
f973ed9c DJ |
4816 | /* Save the provided single-threaded target. We save this in a separate |
4817 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4818 | may have saved a pointer to T; we want to use it for the final | |
4819 | process stratum target. */ | |
4820 | linux_ops_saved = *t; | |
4821 | linux_ops = &linux_ops_saved; | |
4822 | ||
4823 | /* Override some methods for multithreading. */ | |
b84876c2 | 4824 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4825 | t->to_attach = linux_nat_attach; |
4826 | t->to_detach = linux_nat_detach; | |
4827 | t->to_resume = linux_nat_resume; | |
4828 | t->to_wait = linux_nat_wait; | |
2455069d | 4829 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4830 | t->to_xfer_partial = linux_nat_xfer_partial; |
4831 | t->to_kill = linux_nat_kill; | |
4832 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4833 | t->to_thread_alive = linux_nat_thread_alive; | |
4834 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4835 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4836 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4837 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4838 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4839 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
f973ed9c | 4840 | |
b84876c2 PA |
4841 | t->to_can_async_p = linux_nat_can_async_p; |
4842 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4843 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4844 | t->to_async = linux_nat_async; |
b84876c2 PA |
4845 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4846 | t->to_terminal_ours = linux_nat_terminal_ours; | |
d90e17a7 | 4847 | t->to_close = linux_nat_close; |
b84876c2 | 4848 | |
4c28f408 PA |
4849 | /* Methods for non-stop support. */ |
4850 | t->to_stop = linux_nat_stop; | |
4851 | ||
d90e17a7 PA |
4852 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4853 | ||
03583c20 UW |
4854 | t->to_supports_disable_randomization |
4855 | = linux_nat_supports_disable_randomization; | |
4856 | ||
dc146f7c VP |
4857 | t->to_core_of_thread = linux_nat_core_of_thread; |
4858 | ||
f973ed9c DJ |
4859 | /* We don't change the stratum; this target will sit at |
4860 | process_stratum and thread_db will set at thread_stratum. This | |
4861 | is a little strange, since this is a multi-threaded-capable | |
4862 | target, but we want to be on the stack below thread_db, and we | |
4863 | also want to be used for single-threaded processes. */ | |
4864 | ||
4865 | add_target (t); | |
f973ed9c DJ |
4866 | } |
4867 | ||
9f0bdab8 DJ |
4868 | /* Register a method to call whenever a new thread is attached. */ |
4869 | void | |
7b50312a PA |
4870 | linux_nat_set_new_thread (struct target_ops *t, |
4871 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4872 | { |
4873 | /* Save the pointer. We only support a single registered instance | |
4874 | of the GNU/Linux native target, so we do not need to map this to | |
4875 | T. */ | |
4876 | linux_nat_new_thread = new_thread; | |
4877 | } | |
4878 | ||
26cb8b7c PA |
4879 | /* See declaration in linux-nat.h. */ |
4880 | ||
4881 | void | |
4882 | linux_nat_set_new_fork (struct target_ops *t, | |
4883 | linux_nat_new_fork_ftype *new_fork) | |
4884 | { | |
4885 | /* Save the pointer. */ | |
4886 | linux_nat_new_fork = new_fork; | |
4887 | } | |
4888 | ||
4889 | /* See declaration in linux-nat.h. */ | |
4890 | ||
4891 | void | |
4892 | linux_nat_set_forget_process (struct target_ops *t, | |
4893 | linux_nat_forget_process_ftype *fn) | |
4894 | { | |
4895 | /* Save the pointer. */ | |
4896 | linux_nat_forget_process_hook = fn; | |
4897 | } | |
4898 | ||
4899 | /* See declaration in linux-nat.h. */ | |
4900 | ||
4901 | void | |
4902 | linux_nat_forget_process (pid_t pid) | |
4903 | { | |
4904 | if (linux_nat_forget_process_hook != NULL) | |
4905 | linux_nat_forget_process_hook (pid); | |
4906 | } | |
4907 | ||
5b009018 PA |
4908 | /* Register a method that converts a siginfo object between the layout |
4909 | that ptrace returns, and the layout in the architecture of the | |
4910 | inferior. */ | |
4911 | void | |
4912 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4913 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4914 | gdb_byte *, |
4915 | int)) | |
4916 | { | |
4917 | /* Save the pointer. */ | |
4918 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4919 | } | |
4920 | ||
7b50312a PA |
4921 | /* Register a method to call prior to resuming a thread. */ |
4922 | ||
4923 | void | |
4924 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4925 | void (*prepare_to_resume) (struct lwp_info *)) | |
4926 | { | |
4927 | /* Save the pointer. */ | |
4928 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4929 | } | |
4930 | ||
f865ee35 JK |
4931 | /* See linux-nat.h. */ |
4932 | ||
4933 | int | |
4934 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4935 | { |
da559b09 | 4936 | int pid; |
9f0bdab8 | 4937 | |
dfd4cc63 | 4938 | pid = ptid_get_lwp (ptid); |
da559b09 | 4939 | if (pid == 0) |
dfd4cc63 | 4940 | pid = ptid_get_pid (ptid); |
f865ee35 | 4941 | |
da559b09 JK |
4942 | errno = 0; |
4943 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4944 | if (errno != 0) | |
4945 | { | |
4946 | memset (siginfo, 0, sizeof (*siginfo)); | |
4947 | return 0; | |
4948 | } | |
f865ee35 | 4949 | return 1; |
9f0bdab8 DJ |
4950 | } |
4951 | ||
2c0b251b PA |
4952 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4953 | extern initialize_file_ftype _initialize_linux_nat; | |
4954 | ||
d6b0e80f AC |
4955 | void |
4956 | _initialize_linux_nat (void) | |
4957 | { | |
ccce17b0 YQ |
4958 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4959 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4960 | Set debugging of GNU/Linux lwp module."), _("\ |
4961 | Show debugging of GNU/Linux lwp module."), _("\ | |
4962 | Enables printf debugging output."), | |
ccce17b0 YQ |
4963 | NULL, |
4964 | show_debug_linux_nat, | |
4965 | &setdebuglist, &showdebuglist); | |
b84876c2 | 4966 | |
b84876c2 | 4967 | /* Save this mask as the default. */ |
d6b0e80f AC |
4968 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4969 | ||
7feb7d06 PA |
4970 | /* Install a SIGCHLD handler. */ |
4971 | sigchld_action.sa_handler = sigchld_handler; | |
4972 | sigemptyset (&sigchld_action.sa_mask); | |
4973 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
4974 | |
4975 | /* Make it the default. */ | |
7feb7d06 | 4976 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
4977 | |
4978 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4979 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4980 | sigdelset (&suspend_mask, SIGCHLD); | |
4981 | ||
7feb7d06 | 4982 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
4983 | } |
4984 | \f | |
4985 | ||
4986 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4987 | the GNU/Linux Threads library and therefore doesn't really belong | |
4988 | here. */ | |
4989 | ||
4990 | /* Read variable NAME in the target and return its value if found. | |
4991 | Otherwise return zero. It is assumed that the type of the variable | |
4992 | is `int'. */ | |
4993 | ||
4994 | static int | |
4995 | get_signo (const char *name) | |
4996 | { | |
4997 | struct minimal_symbol *ms; | |
4998 | int signo; | |
4999 | ||
5000 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
5001 | if (ms == NULL) | |
5002 | return 0; | |
5003 | ||
8e70166d | 5004 | if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5005 | sizeof (signo)) != 0) |
5006 | return 0; | |
5007 | ||
5008 | return signo; | |
5009 | } | |
5010 | ||
5011 | /* Return the set of signals used by the threads library in *SET. */ | |
5012 | ||
5013 | void | |
5014 | lin_thread_get_thread_signals (sigset_t *set) | |
5015 | { | |
5016 | struct sigaction action; | |
5017 | int restart, cancel; | |
5018 | ||
b84876c2 | 5019 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5020 | sigemptyset (set); |
5021 | ||
5022 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5023 | cancel = get_signo ("__pthread_sig_cancel"); |
5024 | ||
5025 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5026 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5027 | not provide any way for the debugger to query the signal numbers - | |
5028 | fortunately they don't change! */ | |
5029 | ||
d6b0e80f | 5030 | if (restart == 0) |
17fbb0bd | 5031 | restart = __SIGRTMIN; |
d6b0e80f | 5032 | |
d6b0e80f | 5033 | if (cancel == 0) |
17fbb0bd | 5034 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5035 | |
5036 | sigaddset (set, restart); | |
5037 | sigaddset (set, cancel); | |
5038 | ||
5039 | /* The GNU/Linux Threads library makes terminating threads send a | |
5040 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5041 | those (to prevent them from terminating GDB itself, which is | |
5042 | likely to be their default action) and treat them the same way as | |
5043 | SIGCHLD. */ | |
5044 | ||
5045 | action.sa_handler = sigchld_handler; | |
5046 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5047 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5048 | sigaction (cancel, &action, NULL); |
5049 | ||
5050 | /* We block the "cancel" signal throughout this code ... */ | |
5051 | sigaddset (&blocked_mask, cancel); | |
5052 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5053 | ||
5054 | /* ... except during a sigsuspend. */ | |
5055 | sigdelset (&suspend_mask, cancel); | |
5056 | } |