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 */ | |
53ce3c39 | 49 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 50 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
51 | #include "inf-loop.h" |
52 | #include "event-loop.h" | |
53 | #include "event-top.h" | |
07e059b5 VP |
54 | #include <pwd.h> |
55 | #include <sys/types.h> | |
2978b111 | 56 | #include <dirent.h> |
07e059b5 | 57 | #include "xml-support.h" |
191c4426 | 58 | #include "terminal.h" |
efcbbd14 | 59 | #include <sys/vfs.h> |
6c95b8df | 60 | #include "solib.h" |
d26e3629 | 61 | #include "linux-osdata.h" |
6432734d | 62 | #include "linux-tdep.h" |
7dcd53a0 | 63 | #include "symfile.h" |
5808517f YQ |
64 | #include "agent.h" |
65 | #include "tracepoint.h" | |
87b0bb13 | 66 | #include "exceptions.h" |
87b0bb13 | 67 | #include "buffer.h" |
6ecd4729 | 68 | #include "target-descriptions.h" |
614c279d | 69 | #include "filestuff.h" |
efcbbd14 UW |
70 | |
71 | #ifndef SPUFS_MAGIC | |
72 | #define SPUFS_MAGIC 0x23c9b64e | |
73 | #endif | |
dba24537 | 74 | |
10568435 JK |
75 | #ifdef HAVE_PERSONALITY |
76 | # include <sys/personality.h> | |
77 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
78 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
79 | # endif | |
80 | #endif /* HAVE_PERSONALITY */ | |
81 | ||
1777feb0 | 82 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
83 | |
84 | Waiting for events in sync mode | |
85 | =============================== | |
86 | ||
87 | When waiting for an event in a specific thread, we just use waitpid, passing | |
88 | the specific pid, and not passing WNOHANG. | |
89 | ||
1777feb0 | 90 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 91 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 92 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
93 | miss an event. The solution is to use non-blocking waitpid, together with |
94 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 95 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
96 | flag to check for events in cloned processes. If nothing is found, we use |
97 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
98 | happened to a child process -- and SIGCHLD will be delivered both for events | |
99 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
100 | an event, we get back to calling nonblocking waitpid with and without |
101 | __WCLONED. | |
8a77dff3 VP |
102 | |
103 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 104 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
105 | blocked, the signal becomes pending and sigsuspend immediately |
106 | notices it and returns. | |
107 | ||
108 | Waiting for events in async mode | |
109 | ================================ | |
110 | ||
7feb7d06 PA |
111 | In async mode, GDB should always be ready to handle both user input |
112 | and target events, so neither blocking waitpid nor sigsuspend are | |
113 | viable options. Instead, we should asynchronously notify the GDB main | |
114 | event loop whenever there's an unprocessed event from the target. We | |
115 | detect asynchronous target events by handling SIGCHLD signals. To | |
116 | notify the event loop about target events, the self-pipe trick is used | |
117 | --- a pipe is registered as waitable event source in the event loop, | |
118 | the event loop select/poll's on the read end of this pipe (as well on | |
119 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
120 | byte to this pipe. This is more portable than relying on | |
121 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
122 | emulates them with select/poll+sigprocmask, and that is racy | |
123 | (a.k.a. plain broken). | |
124 | ||
125 | Obviously, if we fail to notify the event loop if there's a target | |
126 | event, it's bad. OTOH, if we notify the event loop when there's no | |
127 | event from the target, linux_nat_wait will detect that there's no real | |
128 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
129 | This is mostly harmless, but it will waste time and is better avoided. | |
130 | ||
131 | The main design point is that every time GDB is outside linux-nat.c, | |
132 | we have a SIGCHLD handler installed that is called when something | |
133 | happens to the target and notifies the GDB event loop. Whenever GDB | |
134 | core decides to handle the event, and calls into linux-nat.c, we | |
135 | process things as in sync mode, except that the we never block in | |
136 | sigsuspend. | |
137 | ||
138 | While processing an event, we may end up momentarily blocked in | |
139 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
140 | return quickly. E.g., in all-stop mode, before reporting to the core | |
141 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
142 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
143 | Note that this is different from blocking indefinitely waiting for the | |
144 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
145 | |
146 | Use of signals | |
147 | ============== | |
148 | ||
149 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
150 | signal is not entirely significant; we just need for a signal to be delivered, | |
151 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
152 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
153 | be queued once; we do not keep track of other sources of SIGSTOP. | |
154 | ||
155 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
156 | use them, because they have special behavior when the signal is generated - | |
157 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
158 | kills the entire thread group. | |
159 | ||
160 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
161 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
162 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
163 | ||
164 | We could use a real-time signal instead. This would solve those problems; we | |
165 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
166 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
167 | generates it, and there are races with trying to find a signal that is not | |
168 | blocked. */ | |
a0ef4274 | 169 | |
dba24537 AC |
170 | #ifndef O_LARGEFILE |
171 | #define O_LARGEFILE 0 | |
172 | #endif | |
0274a8ce | 173 | |
10d6c8cd DJ |
174 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
175 | the use of the multi-threaded target. */ | |
176 | static struct target_ops *linux_ops; | |
f973ed9c | 177 | static struct target_ops linux_ops_saved; |
10d6c8cd | 178 | |
9f0bdab8 | 179 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
180 | static void (*linux_nat_new_thread) (struct lwp_info *); |
181 | ||
26cb8b7c PA |
182 | /* The method to call, if any, when a new fork is attached. */ |
183 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
184 | ||
185 | /* The method to call, if any, when a process is no longer | |
186 | attached. */ | |
187 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
188 | ||
7b50312a PA |
189 | /* Hook to call prior to resuming a thread. */ |
190 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 191 | |
5b009018 PA |
192 | /* The method to call, if any, when the siginfo object needs to be |
193 | converted between the layout returned by ptrace, and the layout in | |
194 | the architecture of the inferior. */ | |
a5362b9a | 195 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
196 | gdb_byte *, |
197 | int); | |
198 | ||
ac264b3b MS |
199 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
200 | Called by our to_xfer_partial. */ | |
4ac248ca | 201 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 202 | |
ccce17b0 | 203 | static unsigned int debug_linux_nat; |
920d2a44 AC |
204 | static void |
205 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
206 | struct cmd_list_element *c, const char *value) | |
207 | { | |
208 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
209 | value); | |
210 | } | |
d6b0e80f | 211 | |
ae087d01 DJ |
212 | struct simple_pid_list |
213 | { | |
214 | int pid; | |
3d799a95 | 215 | int status; |
ae087d01 DJ |
216 | struct simple_pid_list *next; |
217 | }; | |
218 | struct simple_pid_list *stopped_pids; | |
219 | ||
3dd5b83d PA |
220 | /* Async mode support. */ |
221 | ||
b84876c2 PA |
222 | /* The read/write ends of the pipe registered as waitable file in the |
223 | event loop. */ | |
224 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
225 | ||
7feb7d06 | 226 | /* Flush the event pipe. */ |
b84876c2 | 227 | |
7feb7d06 PA |
228 | static void |
229 | async_file_flush (void) | |
b84876c2 | 230 | { |
7feb7d06 PA |
231 | int ret; |
232 | char buf; | |
b84876c2 | 233 | |
7feb7d06 | 234 | do |
b84876c2 | 235 | { |
7feb7d06 | 236 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 237 | } |
7feb7d06 | 238 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
239 | } |
240 | ||
7feb7d06 PA |
241 | /* Put something (anything, doesn't matter what, or how much) in event |
242 | pipe, so that the select/poll in the event-loop realizes we have | |
243 | something to process. */ | |
252fbfc8 | 244 | |
b84876c2 | 245 | static void |
7feb7d06 | 246 | async_file_mark (void) |
b84876c2 | 247 | { |
7feb7d06 | 248 | int ret; |
b84876c2 | 249 | |
7feb7d06 PA |
250 | /* It doesn't really matter what the pipe contains, as long we end |
251 | up with something in it. Might as well flush the previous | |
252 | left-overs. */ | |
253 | async_file_flush (); | |
b84876c2 | 254 | |
7feb7d06 | 255 | do |
b84876c2 | 256 | { |
7feb7d06 | 257 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 258 | } |
7feb7d06 | 259 | while (ret == -1 && errno == EINTR); |
b84876c2 | 260 | |
7feb7d06 PA |
261 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
262 | be awakened anyway. */ | |
b84876c2 PA |
263 | } |
264 | ||
7feb7d06 | 265 | static void linux_nat_async (void (*callback) |
3e43a32a MS |
266 | (enum inferior_event_type event_type, |
267 | void *context), | |
7feb7d06 | 268 | void *context); |
7feb7d06 PA |
269 | static int kill_lwp (int lwpid, int signo); |
270 | ||
271 | static int stop_callback (struct lwp_info *lp, void *data); | |
272 | ||
273 | static void block_child_signals (sigset_t *prev_mask); | |
274 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
275 | |
276 | struct lwp_info; | |
277 | static struct lwp_info *add_lwp (ptid_t ptid); | |
278 | static void purge_lwp_list (int pid); | |
4403d8e9 | 279 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
280 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
281 | ||
ae087d01 DJ |
282 | \f |
283 | /* Trivial list manipulation functions to keep track of a list of | |
284 | new stopped processes. */ | |
285 | static void | |
3d799a95 | 286 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
287 | { |
288 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 289 | |
ae087d01 | 290 | new_pid->pid = pid; |
3d799a95 | 291 | new_pid->status = status; |
ae087d01 DJ |
292 | new_pid->next = *listp; |
293 | *listp = new_pid; | |
294 | } | |
295 | ||
84636d28 PA |
296 | static int |
297 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
298 | { | |
299 | struct simple_pid_list *p; | |
300 | ||
301 | for (p = list; p != NULL; p = p->next) | |
302 | if (p->pid == pid) | |
303 | return 1; | |
304 | return 0; | |
305 | } | |
306 | ||
ae087d01 | 307 | static int |
46a96992 | 308 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
309 | { |
310 | struct simple_pid_list **p; | |
311 | ||
312 | for (p = listp; *p != NULL; p = &(*p)->next) | |
313 | if ((*p)->pid == pid) | |
314 | { | |
315 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 316 | |
46a96992 | 317 | *statusp = (*p)->status; |
ae087d01 DJ |
318 | xfree (*p); |
319 | *p = next; | |
320 | return 1; | |
321 | } | |
322 | return 0; | |
323 | } | |
324 | ||
96d7229d LM |
325 | /* Initialize ptrace warnings and check for supported ptrace |
326 | features given PID. */ | |
3993f6b1 DJ |
327 | |
328 | static void | |
96d7229d | 329 | linux_init_ptrace (pid_t pid) |
3993f6b1 | 330 | { |
96d7229d LM |
331 | linux_enable_event_reporting (pid); |
332 | linux_ptrace_init_warnings (); | |
4de4c07c DJ |
333 | } |
334 | ||
6d8fd2b7 UW |
335 | static void |
336 | linux_child_post_attach (int pid) | |
4de4c07c | 337 | { |
96d7229d | 338 | linux_init_ptrace (pid); |
4de4c07c DJ |
339 | } |
340 | ||
10d6c8cd | 341 | static void |
4de4c07c DJ |
342 | linux_child_post_startup_inferior (ptid_t ptid) |
343 | { | |
96d7229d | 344 | linux_init_ptrace (ptid_get_pid (ptid)); |
4de4c07c DJ |
345 | } |
346 | ||
4403d8e9 JK |
347 | /* Return the number of known LWPs in the tgid given by PID. */ |
348 | ||
349 | static int | |
350 | num_lwps (int pid) | |
351 | { | |
352 | int count = 0; | |
353 | struct lwp_info *lp; | |
354 | ||
355 | for (lp = lwp_list; lp; lp = lp->next) | |
356 | if (ptid_get_pid (lp->ptid) == pid) | |
357 | count++; | |
358 | ||
359 | return count; | |
360 | } | |
361 | ||
362 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
363 | ||
364 | static void | |
365 | delete_lwp_cleanup (void *lp_voidp) | |
366 | { | |
367 | struct lwp_info *lp = lp_voidp; | |
368 | ||
369 | delete_lwp (lp->ptid); | |
370 | } | |
371 | ||
6d8fd2b7 | 372 | static int |
07107ca6 LM |
373 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
374 | int detach_fork) | |
3993f6b1 | 375 | { |
9016a515 | 376 | int has_vforked; |
4de4c07c DJ |
377 | int parent_pid, child_pid; |
378 | ||
e58b0e63 PA |
379 | has_vforked = (inferior_thread ()->pending_follow.kind |
380 | == TARGET_WAITKIND_VFORKED); | |
381 | parent_pid = ptid_get_lwp (inferior_ptid); | |
d3587048 | 382 | if (parent_pid == 0) |
e58b0e63 | 383 | parent_pid = ptid_get_pid (inferior_ptid); |
dfd4cc63 LM |
384 | child_pid |
385 | = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid); | |
4de4c07c | 386 | |
6c95b8df PA |
387 | if (has_vforked |
388 | && !non_stop /* Non-stop always resumes both branches. */ | |
389 | && (!target_is_async_p () || sync_execution) | |
390 | && !(follow_child || detach_fork || sched_multi)) | |
391 | { | |
392 | /* The parent stays blocked inside the vfork syscall until the | |
393 | child execs or exits. If we don't let the child run, then | |
394 | the parent stays blocked. If we're telling the parent to run | |
395 | in the foreground, the user will not be able to ctrl-c to get | |
396 | back the terminal, effectively hanging the debug session. */ | |
ac74f770 MS |
397 | fprintf_filtered (gdb_stderr, _("\ |
398 | Can not resume the parent process over vfork in the foreground while\n\ | |
399 | holding the child stopped. Try \"set detach-on-fork\" or \ | |
400 | \"set schedule-multiple\".\n")); | |
401 | /* FIXME output string > 80 columns. */ | |
6c95b8df PA |
402 | return 1; |
403 | } | |
404 | ||
4de4c07c DJ |
405 | if (! follow_child) |
406 | { | |
6c95b8df | 407 | struct lwp_info *child_lp = NULL; |
4de4c07c | 408 | |
1777feb0 | 409 | /* We're already attached to the parent, by default. */ |
4de4c07c | 410 | |
ac264b3b MS |
411 | /* Detach new forked process? */ |
412 | if (detach_fork) | |
f75c00e4 | 413 | { |
4403d8e9 JK |
414 | struct cleanup *old_chain; |
415 | ||
6c95b8df PA |
416 | /* Before detaching from the child, remove all breakpoints |
417 | from it. If we forked, then this has already been taken | |
418 | care of by infrun.c. If we vforked however, any | |
419 | breakpoint inserted in the parent is visible in the | |
420 | child, even those added while stopped in a vfork | |
421 | catchpoint. This will remove the breakpoints from the | |
422 | parent also, but they'll be reinserted below. */ | |
423 | if (has_vforked) | |
424 | { | |
425 | /* keep breakpoints list in sync. */ | |
dfd4cc63 | 426 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
6c95b8df PA |
427 | } |
428 | ||
e85a822c | 429 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
430 | { |
431 | target_terminal_ours (); | |
432 | fprintf_filtered (gdb_stdlog, | |
3e43a32a MS |
433 | "Detaching after fork from " |
434 | "child process %d.\n", | |
ac264b3b MS |
435 | child_pid); |
436 | } | |
4de4c07c | 437 | |
4403d8e9 JK |
438 | old_chain = save_inferior_ptid (); |
439 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
440 | ||
441 | child_lp = add_lwp (inferior_ptid); | |
442 | child_lp->stopped = 1; | |
443 | child_lp->last_resume_kind = resume_stop; | |
444 | make_cleanup (delete_lwp_cleanup, child_lp); | |
445 | ||
4403d8e9 JK |
446 | if (linux_nat_prepare_to_resume != NULL) |
447 | linux_nat_prepare_to_resume (child_lp); | |
ac264b3b | 448 | ptrace (PTRACE_DETACH, child_pid, 0, 0); |
4403d8e9 JK |
449 | |
450 | do_cleanups (old_chain); | |
ac264b3b MS |
451 | } |
452 | else | |
453 | { | |
77435e4c | 454 | struct inferior *parent_inf, *child_inf; |
2277426b | 455 | struct cleanup *old_chain; |
7f9f62ba PA |
456 | |
457 | /* Add process to GDB's tables. */ | |
77435e4c PA |
458 | child_inf = add_inferior (child_pid); |
459 | ||
e58b0e63 | 460 | parent_inf = current_inferior (); |
77435e4c | 461 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 462 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
463 | child_inf->gdbarch = parent_inf->gdbarch; |
464 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7f9f62ba | 465 | |
2277426b | 466 | old_chain = save_inferior_ptid (); |
6c95b8df | 467 | save_current_program_space (); |
2277426b PA |
468 | |
469 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
470 | add_thread (inferior_ptid); | |
6c95b8df PA |
471 | child_lp = add_lwp (inferior_ptid); |
472 | child_lp->stopped = 1; | |
25289eb2 | 473 | child_lp->last_resume_kind = resume_stop; |
7dcd53a0 | 474 | child_inf->symfile_flags = SYMFILE_NO_READ; |
2277426b | 475 | |
6c95b8df PA |
476 | /* If this is a vfork child, then the address-space is |
477 | shared with the parent. */ | |
478 | if (has_vforked) | |
479 | { | |
480 | child_inf->pspace = parent_inf->pspace; | |
481 | child_inf->aspace = parent_inf->aspace; | |
482 | ||
483 | /* The parent will be frozen until the child is done | |
484 | with the shared region. Keep track of the | |
485 | parent. */ | |
486 | child_inf->vfork_parent = parent_inf; | |
487 | child_inf->pending_detach = 0; | |
488 | parent_inf->vfork_child = child_inf; | |
489 | parent_inf->pending_detach = 0; | |
490 | } | |
491 | else | |
492 | { | |
493 | child_inf->aspace = new_address_space (); | |
494 | child_inf->pspace = add_program_space (child_inf->aspace); | |
495 | child_inf->removable = 1; | |
496 | set_current_program_space (child_inf->pspace); | |
497 | clone_program_space (child_inf->pspace, parent_inf->pspace); | |
498 | ||
499 | /* Let the shared library layer (solib-svr4) learn about | |
500 | this new process, relocate the cloned exec, pull in | |
501 | shared libraries, and install the solib event | |
502 | breakpoint. If a "cloned-VM" event was propagated | |
503 | better throughout the core, this wouldn't be | |
504 | required. */ | |
268a4a75 | 505 | solib_create_inferior_hook (0); |
6c95b8df PA |
506 | } |
507 | ||
508 | /* Let the thread_db layer learn about this new process. */ | |
2277426b PA |
509 | check_for_thread_db (); |
510 | ||
511 | do_cleanups (old_chain); | |
ac264b3b | 512 | } |
9016a515 DJ |
513 | |
514 | if (has_vforked) | |
515 | { | |
3ced3da4 | 516 | struct lwp_info *parent_lp; |
6c95b8df PA |
517 | struct inferior *parent_inf; |
518 | ||
519 | parent_inf = current_inferior (); | |
520 | ||
521 | /* If we detached from the child, then we have to be careful | |
522 | to not insert breakpoints in the parent until the child | |
523 | is done with the shared memory region. However, if we're | |
524 | staying attached to the child, then we can and should | |
525 | insert breakpoints, so that we can debug it. A | |
526 | subsequent child exec or exit is enough to know when does | |
527 | the child stops using the parent's address space. */ | |
528 | parent_inf->waiting_for_vfork_done = detach_fork; | |
56710373 | 529 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
6c95b8df | 530 | |
3ced3da4 | 531 | parent_lp = find_lwp_pid (pid_to_ptid (parent_pid)); |
96d7229d | 532 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 533 | |
96d7229d | 534 | if (linux_supports_tracevforkdone ()) |
9016a515 | 535 | { |
6c95b8df PA |
536 | if (debug_linux_nat) |
537 | fprintf_unfiltered (gdb_stdlog, | |
538 | "LCFF: waiting for VFORK_DONE on %d\n", | |
539 | parent_pid); | |
3ced3da4 | 540 | parent_lp->stopped = 1; |
9016a515 | 541 | |
6c95b8df PA |
542 | /* We'll handle the VFORK_DONE event like any other |
543 | event, in target_wait. */ | |
9016a515 DJ |
544 | } |
545 | else | |
546 | { | |
547 | /* We can't insert breakpoints until the child has | |
548 | finished with the shared memory region. We need to | |
549 | wait until that happens. Ideal would be to just | |
550 | call: | |
551 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
552 | - waitpid (parent_pid, &status, __WALL); | |
553 | However, most architectures can't handle a syscall | |
554 | being traced on the way out if it wasn't traced on | |
555 | the way in. | |
556 | ||
557 | We might also think to loop, continuing the child | |
558 | until it exits or gets a SIGTRAP. One problem is | |
559 | that the child might call ptrace with PTRACE_TRACEME. | |
560 | ||
561 | There's no simple and reliable way to figure out when | |
562 | the vforked child will be done with its copy of the | |
563 | shared memory. We could step it out of the syscall, | |
564 | two instructions, let it go, and then single-step the | |
565 | parent once. When we have hardware single-step, this | |
566 | would work; with software single-step it could still | |
567 | be made to work but we'd have to be able to insert | |
568 | single-step breakpoints in the child, and we'd have | |
569 | to insert -just- the single-step breakpoint in the | |
570 | parent. Very awkward. | |
571 | ||
572 | In the end, the best we can do is to make sure it | |
573 | runs for a little while. Hopefully it will be out of | |
574 | range of any breakpoints we reinsert. Usually this | |
575 | is only the single-step breakpoint at vfork's return | |
576 | point. */ | |
577 | ||
6c95b8df PA |
578 | if (debug_linux_nat) |
579 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
580 | "LCFF: no VFORK_DONE " |
581 | "support, sleeping a bit\n"); | |
6c95b8df | 582 | |
9016a515 | 583 | usleep (10000); |
9016a515 | 584 | |
6c95b8df PA |
585 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
586 | and leave it pending. The next linux_nat_resume call | |
587 | will notice a pending event, and bypasses actually | |
588 | resuming the inferior. */ | |
3ced3da4 PA |
589 | parent_lp->status = 0; |
590 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
591 | parent_lp->stopped = 1; | |
6c95b8df PA |
592 | |
593 | /* If we're in async mode, need to tell the event loop | |
594 | there's something here to process. */ | |
595 | if (target_can_async_p ()) | |
596 | async_file_mark (); | |
597 | } | |
9016a515 | 598 | } |
4de4c07c | 599 | } |
3993f6b1 | 600 | else |
4de4c07c | 601 | { |
77435e4c | 602 | struct inferior *parent_inf, *child_inf; |
3ced3da4 | 603 | struct lwp_info *child_lp; |
6c95b8df | 604 | struct program_space *parent_pspace; |
4de4c07c | 605 | |
e85a822c | 606 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
607 | { |
608 | target_terminal_ours (); | |
6c95b8df | 609 | if (has_vforked) |
3e43a32a MS |
610 | fprintf_filtered (gdb_stdlog, |
611 | _("Attaching after process %d " | |
612 | "vfork to child process %d.\n"), | |
6c95b8df PA |
613 | parent_pid, child_pid); |
614 | else | |
3e43a32a MS |
615 | fprintf_filtered (gdb_stdlog, |
616 | _("Attaching after process %d " | |
617 | "fork to child process %d.\n"), | |
6c95b8df | 618 | parent_pid, child_pid); |
f75c00e4 | 619 | } |
4de4c07c | 620 | |
7a7d3353 PA |
621 | /* Add the new inferior first, so that the target_detach below |
622 | doesn't unpush the target. */ | |
623 | ||
77435e4c PA |
624 | child_inf = add_inferior (child_pid); |
625 | ||
e58b0e63 | 626 | parent_inf = current_inferior (); |
77435e4c | 627 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 628 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
629 | child_inf->gdbarch = parent_inf->gdbarch; |
630 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7a7d3353 | 631 | |
6c95b8df | 632 | parent_pspace = parent_inf->pspace; |
9016a515 | 633 | |
6c95b8df PA |
634 | /* If we're vforking, we want to hold on to the parent until the |
635 | child exits or execs. At child exec or exit time we can | |
636 | remove the old breakpoints from the parent and detach or | |
637 | resume debugging it. Otherwise, detach the parent now; we'll | |
638 | want to reuse it's program/address spaces, but we can't set | |
639 | them to the child before removing breakpoints from the | |
640 | parent, otherwise, the breakpoints module could decide to | |
641 | remove breakpoints from the wrong process (since they'd be | |
642 | assigned to the same address space). */ | |
9016a515 DJ |
643 | |
644 | if (has_vforked) | |
7f9f62ba | 645 | { |
6c95b8df PA |
646 | gdb_assert (child_inf->vfork_parent == NULL); |
647 | gdb_assert (parent_inf->vfork_child == NULL); | |
648 | child_inf->vfork_parent = parent_inf; | |
649 | child_inf->pending_detach = 0; | |
650 | parent_inf->vfork_child = child_inf; | |
651 | parent_inf->pending_detach = detach_fork; | |
652 | parent_inf->waiting_for_vfork_done = 0; | |
ac264b3b | 653 | } |
2277426b | 654 | else if (detach_fork) |
b84876c2 | 655 | target_detach (NULL, 0); |
4de4c07c | 656 | |
6c95b8df PA |
657 | /* Note that the detach above makes PARENT_INF dangling. */ |
658 | ||
659 | /* Add the child thread to the appropriate lists, and switch to | |
660 | this new thread, before cloning the program space, and | |
661 | informing the solib layer about this new process. */ | |
662 | ||
9f0bdab8 | 663 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
2277426b | 664 | add_thread (inferior_ptid); |
3ced3da4 PA |
665 | child_lp = add_lwp (inferior_ptid); |
666 | child_lp->stopped = 1; | |
25289eb2 | 667 | child_lp->last_resume_kind = resume_stop; |
6c95b8df PA |
668 | |
669 | /* If this is a vfork child, then the address-space is shared | |
670 | with the parent. If we detached from the parent, then we can | |
671 | reuse the parent's program/address spaces. */ | |
672 | if (has_vforked || detach_fork) | |
673 | { | |
674 | child_inf->pspace = parent_pspace; | |
675 | child_inf->aspace = child_inf->pspace->aspace; | |
676 | } | |
677 | else | |
678 | { | |
679 | child_inf->aspace = new_address_space (); | |
680 | child_inf->pspace = add_program_space (child_inf->aspace); | |
681 | child_inf->removable = 1; | |
7dcd53a0 | 682 | child_inf->symfile_flags = SYMFILE_NO_READ; |
6c95b8df PA |
683 | set_current_program_space (child_inf->pspace); |
684 | clone_program_space (child_inf->pspace, parent_pspace); | |
685 | ||
686 | /* Let the shared library layer (solib-svr4) learn about | |
687 | this new process, relocate the cloned exec, pull in | |
688 | shared libraries, and install the solib event breakpoint. | |
689 | If a "cloned-VM" event was propagated better throughout | |
690 | the core, this wouldn't be required. */ | |
268a4a75 | 691 | solib_create_inferior_hook (0); |
6c95b8df | 692 | } |
ac264b3b | 693 | |
6c95b8df | 694 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 695 | check_for_thread_db (); |
4de4c07c DJ |
696 | } |
697 | ||
698 | return 0; | |
699 | } | |
700 | ||
4de4c07c | 701 | \f |
77b06cd7 | 702 | static int |
6d8fd2b7 | 703 | linux_child_insert_fork_catchpoint (int pid) |
4de4c07c | 704 | { |
96d7229d | 705 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
706 | } |
707 | ||
eb73ad13 PA |
708 | static int |
709 | linux_child_remove_fork_catchpoint (int pid) | |
710 | { | |
711 | return 0; | |
712 | } | |
713 | ||
77b06cd7 | 714 | static int |
6d8fd2b7 | 715 | linux_child_insert_vfork_catchpoint (int pid) |
3993f6b1 | 716 | { |
96d7229d | 717 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
718 | } |
719 | ||
eb73ad13 PA |
720 | static int |
721 | linux_child_remove_vfork_catchpoint (int pid) | |
722 | { | |
723 | return 0; | |
724 | } | |
725 | ||
77b06cd7 | 726 | static int |
6d8fd2b7 | 727 | linux_child_insert_exec_catchpoint (int pid) |
3993f6b1 | 728 | { |
96d7229d | 729 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
730 | } |
731 | ||
eb73ad13 PA |
732 | static int |
733 | linux_child_remove_exec_catchpoint (int pid) | |
734 | { | |
735 | return 0; | |
736 | } | |
737 | ||
a96d9b2e SDJ |
738 | static int |
739 | linux_child_set_syscall_catchpoint (int pid, int needed, int any_count, | |
740 | int table_size, int *table) | |
741 | { | |
96d7229d | 742 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
743 | return 1; |
744 | ||
a96d9b2e SDJ |
745 | /* On GNU/Linux, we ignore the arguments. It means that we only |
746 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 747 | |
a96d9b2e SDJ |
748 | Also, we do not use the `table' information because we do not |
749 | filter system calls here. We let GDB do the logic for us. */ | |
750 | return 0; | |
751 | } | |
752 | ||
d6b0e80f AC |
753 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
754 | are processes sharing the same VM space. A multi-threaded process | |
755 | is basically a group of such processes. However, such a grouping | |
756 | is almost entirely a user-space issue; the kernel doesn't enforce | |
757 | such a grouping at all (this might change in the future). In | |
758 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
759 | Threads library) to provide such a grouping. | |
760 | ||
761 | It is perfectly well possible to write a multi-threaded application | |
762 | without the assistance of a threads library, by using the clone | |
763 | system call directly. This module should be able to give some | |
764 | rudimentary support for debugging such applications if developers | |
765 | specify the CLONE_PTRACE flag in the clone system call, and are | |
766 | using the Linux kernel 2.4 or above. | |
767 | ||
768 | Note that there are some peculiarities in GNU/Linux that affect | |
769 | this code: | |
770 | ||
771 | - In general one should specify the __WCLONE flag to waitpid in | |
772 | order to make it report events for any of the cloned processes | |
773 | (and leave it out for the initial process). However, if a cloned | |
774 | process has exited the exit status is only reported if the | |
775 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
776 | we cannot use it since GDB must work on older systems too. | |
777 | ||
778 | - When a traced, cloned process exits and is waited for by the | |
779 | debugger, the kernel reassigns it to the original parent and | |
780 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
781 | library doesn't notice this, which leads to the "zombie problem": | |
782 | When debugged a multi-threaded process that spawns a lot of | |
783 | threads will run out of processes, even if the threads exit, | |
784 | because the "zombies" stay around. */ | |
785 | ||
786 | /* List of known LWPs. */ | |
9f0bdab8 | 787 | struct lwp_info *lwp_list; |
d6b0e80f AC |
788 | \f |
789 | ||
d6b0e80f AC |
790 | /* Original signal mask. */ |
791 | static sigset_t normal_mask; | |
792 | ||
793 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
794 | _initialize_linux_nat. */ | |
795 | static sigset_t suspend_mask; | |
796 | ||
7feb7d06 PA |
797 | /* Signals to block to make that sigsuspend work. */ |
798 | static sigset_t blocked_mask; | |
799 | ||
800 | /* SIGCHLD action. */ | |
801 | struct sigaction sigchld_action; | |
b84876c2 | 802 | |
7feb7d06 PA |
803 | /* Block child signals (SIGCHLD and linux threads signals), and store |
804 | the previous mask in PREV_MASK. */ | |
84e46146 | 805 | |
7feb7d06 PA |
806 | static void |
807 | block_child_signals (sigset_t *prev_mask) | |
808 | { | |
809 | /* Make sure SIGCHLD is blocked. */ | |
810 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
811 | sigaddset (&blocked_mask, SIGCHLD); | |
812 | ||
813 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
814 | } | |
815 | ||
816 | /* Restore child signals mask, previously returned by | |
817 | block_child_signals. */ | |
818 | ||
819 | static void | |
820 | restore_child_signals_mask (sigset_t *prev_mask) | |
821 | { | |
822 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
823 | } | |
2455069d UW |
824 | |
825 | /* Mask of signals to pass directly to the inferior. */ | |
826 | static sigset_t pass_mask; | |
827 | ||
828 | /* Update signals to pass to the inferior. */ | |
829 | static void | |
830 | linux_nat_pass_signals (int numsigs, unsigned char *pass_signals) | |
831 | { | |
832 | int signo; | |
833 | ||
834 | sigemptyset (&pass_mask); | |
835 | ||
836 | for (signo = 1; signo < NSIG; signo++) | |
837 | { | |
2ea28649 | 838 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
839 | if (target_signo < numsigs && pass_signals[target_signo]) |
840 | sigaddset (&pass_mask, signo); | |
841 | } | |
842 | } | |
843 | ||
d6b0e80f AC |
844 | \f |
845 | ||
846 | /* Prototypes for local functions. */ | |
847 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 848 | static int linux_thread_alive (ptid_t ptid); |
6d8fd2b7 | 849 | static char *linux_child_pid_to_exec_file (int pid); |
710151dd | 850 | |
d6b0e80f AC |
851 | \f |
852 | /* Convert wait status STATUS to a string. Used for printing debug | |
853 | messages only. */ | |
854 | ||
855 | static char * | |
856 | status_to_str (int status) | |
857 | { | |
858 | static char buf[64]; | |
859 | ||
860 | if (WIFSTOPPED (status)) | |
206aa767 | 861 | { |
ca2163eb | 862 | if (WSTOPSIG (status) == SYSCALL_SIGTRAP) |
206aa767 DE |
863 | snprintf (buf, sizeof (buf), "%s (stopped at syscall)", |
864 | strsignal (SIGTRAP)); | |
865 | else | |
866 | snprintf (buf, sizeof (buf), "%s (stopped)", | |
867 | strsignal (WSTOPSIG (status))); | |
868 | } | |
d6b0e80f AC |
869 | else if (WIFSIGNALED (status)) |
870 | snprintf (buf, sizeof (buf), "%s (terminated)", | |
ba9b2ec3 | 871 | strsignal (WTERMSIG (status))); |
d6b0e80f AC |
872 | else |
873 | snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status)); | |
874 | ||
875 | return buf; | |
876 | } | |
877 | ||
7b50312a PA |
878 | /* Destroy and free LP. */ |
879 | ||
880 | static void | |
881 | lwp_free (struct lwp_info *lp) | |
882 | { | |
883 | xfree (lp->arch_private); | |
884 | xfree (lp); | |
885 | } | |
886 | ||
d90e17a7 PA |
887 | /* Remove all LWPs belong to PID from the lwp list. */ |
888 | ||
889 | static void | |
890 | purge_lwp_list (int pid) | |
891 | { | |
892 | struct lwp_info *lp, *lpprev, *lpnext; | |
893 | ||
894 | lpprev = NULL; | |
895 | ||
896 | for (lp = lwp_list; lp; lp = lpnext) | |
897 | { | |
898 | lpnext = lp->next; | |
899 | ||
900 | if (ptid_get_pid (lp->ptid) == pid) | |
901 | { | |
902 | if (lp == lwp_list) | |
903 | lwp_list = lp->next; | |
904 | else | |
905 | lpprev->next = lp->next; | |
906 | ||
7b50312a | 907 | lwp_free (lp); |
d90e17a7 PA |
908 | } |
909 | else | |
910 | lpprev = lp; | |
911 | } | |
912 | } | |
913 | ||
26cb8b7c PA |
914 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
915 | in the process. Return a pointer to the structure describing the | |
916 | new LWP. | |
917 | ||
918 | This differs from add_lwp in that we don't let the arch specific | |
919 | bits know about this new thread. Current clients of this callback | |
920 | take the opportunity to install watchpoints in the new thread, and | |
921 | we shouldn't do that for the first thread. If we're spawning a | |
922 | child ("run"), the thread executes the shell wrapper first, and we | |
923 | shouldn't touch it until it execs the program we want to debug. | |
924 | For "attach", it'd be okay to call the callback, but it's not | |
925 | necessary, because watchpoints can't yet have been inserted into | |
926 | the inferior. */ | |
d6b0e80f AC |
927 | |
928 | static struct lwp_info * | |
26cb8b7c | 929 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
930 | { |
931 | struct lwp_info *lp; | |
932 | ||
dfd4cc63 | 933 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
934 | |
935 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
936 | ||
937 | memset (lp, 0, sizeof (struct lwp_info)); | |
938 | ||
25289eb2 | 939 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
940 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
941 | ||
942 | lp->ptid = ptid; | |
dc146f7c | 943 | lp->core = -1; |
d6b0e80f AC |
944 | |
945 | lp->next = lwp_list; | |
946 | lwp_list = lp; | |
d6b0e80f | 947 | |
26cb8b7c PA |
948 | return lp; |
949 | } | |
950 | ||
951 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
952 | structure describing the new LWP. The LWP should already be | |
953 | stopped. */ | |
954 | ||
955 | static struct lwp_info * | |
956 | add_lwp (ptid_t ptid) | |
957 | { | |
958 | struct lwp_info *lp; | |
959 | ||
960 | lp = add_initial_lwp (ptid); | |
961 | ||
6e012a6c PA |
962 | /* Let the arch specific bits know about this new thread. Current |
963 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
964 | watchpoints in the new thread. We don't do this for the first |
965 | thread though. See add_initial_lwp. */ | |
966 | if (linux_nat_new_thread != NULL) | |
7b50312a | 967 | linux_nat_new_thread (lp); |
9f0bdab8 | 968 | |
d6b0e80f AC |
969 | return lp; |
970 | } | |
971 | ||
972 | /* Remove the LWP specified by PID from the list. */ | |
973 | ||
974 | static void | |
975 | delete_lwp (ptid_t ptid) | |
976 | { | |
977 | struct lwp_info *lp, *lpprev; | |
978 | ||
979 | lpprev = NULL; | |
980 | ||
981 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
982 | if (ptid_equal (lp->ptid, ptid)) | |
983 | break; | |
984 | ||
985 | if (!lp) | |
986 | return; | |
987 | ||
d6b0e80f AC |
988 | if (lpprev) |
989 | lpprev->next = lp->next; | |
990 | else | |
991 | lwp_list = lp->next; | |
992 | ||
7b50312a | 993 | lwp_free (lp); |
d6b0e80f AC |
994 | } |
995 | ||
996 | /* Return a pointer to the structure describing the LWP corresponding | |
997 | to PID. If no corresponding LWP could be found, return NULL. */ | |
998 | ||
999 | static struct lwp_info * | |
1000 | find_lwp_pid (ptid_t ptid) | |
1001 | { | |
1002 | struct lwp_info *lp; | |
1003 | int lwp; | |
1004 | ||
dfd4cc63 LM |
1005 | if (ptid_lwp_p (ptid)) |
1006 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 1007 | else |
dfd4cc63 | 1008 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
1009 | |
1010 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 1011 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
1012 | return lp; |
1013 | ||
1014 | return NULL; | |
1015 | } | |
1016 | ||
1017 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1018 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1019 | pointer to the structure describing that LWP immediately. | |
1020 | Otherwise return NULL. */ | |
1021 | ||
1022 | struct lwp_info * | |
d90e17a7 PA |
1023 | iterate_over_lwps (ptid_t filter, |
1024 | int (*callback) (struct lwp_info *, void *), | |
1025 | void *data) | |
d6b0e80f AC |
1026 | { |
1027 | struct lwp_info *lp, *lpnext; | |
1028 | ||
1029 | for (lp = lwp_list; lp; lp = lpnext) | |
1030 | { | |
1031 | lpnext = lp->next; | |
d90e17a7 PA |
1032 | |
1033 | if (ptid_match (lp->ptid, filter)) | |
1034 | { | |
1035 | if ((*callback) (lp, data)) | |
1036 | return lp; | |
1037 | } | |
d6b0e80f AC |
1038 | } |
1039 | ||
1040 | return NULL; | |
1041 | } | |
1042 | ||
2277426b PA |
1043 | /* Update our internal state when changing from one checkpoint to |
1044 | another indicated by NEW_PTID. We can only switch single-threaded | |
1045 | applications, so we only create one new LWP, and the previous list | |
1046 | is discarded. */ | |
f973ed9c DJ |
1047 | |
1048 | void | |
1049 | linux_nat_switch_fork (ptid_t new_ptid) | |
1050 | { | |
1051 | struct lwp_info *lp; | |
1052 | ||
dfd4cc63 | 1053 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 1054 | |
f973ed9c DJ |
1055 | lp = add_lwp (new_ptid); |
1056 | lp->stopped = 1; | |
e26af52f | 1057 | |
2277426b PA |
1058 | /* This changes the thread's ptid while preserving the gdb thread |
1059 | num. Also changes the inferior pid, while preserving the | |
1060 | inferior num. */ | |
1061 | thread_change_ptid (inferior_ptid, new_ptid); | |
1062 | ||
1063 | /* We've just told GDB core that the thread changed target id, but, | |
1064 | in fact, it really is a different thread, with different register | |
1065 | contents. */ | |
1066 | registers_changed (); | |
e26af52f DJ |
1067 | } |
1068 | ||
e26af52f DJ |
1069 | /* Handle the exit of a single thread LP. */ |
1070 | ||
1071 | static void | |
1072 | exit_lwp (struct lwp_info *lp) | |
1073 | { | |
e09875d4 | 1074 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1075 | |
1076 | if (th) | |
e26af52f | 1077 | { |
17faa917 DJ |
1078 | if (print_thread_events) |
1079 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1080 | ||
4f8d22e3 | 1081 | delete_thread (lp->ptid); |
e26af52f DJ |
1082 | } |
1083 | ||
1084 | delete_lwp (lp->ptid); | |
1085 | } | |
1086 | ||
a0ef4274 DJ |
1087 | /* Wait for the LWP specified by LP, which we have just attached to. |
1088 | Returns a wait status for that LWP, to cache. */ | |
1089 | ||
1090 | static int | |
1091 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1092 | int *signalled) | |
1093 | { | |
dfd4cc63 | 1094 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
1095 | int status; |
1096 | ||
644cebc9 | 1097 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1098 | { |
1099 | if (debug_linux_nat) | |
1100 | fprintf_unfiltered (gdb_stdlog, | |
1101 | "LNPAW: Attaching to a stopped process\n"); | |
1102 | ||
1103 | /* The process is definitely stopped. It is in a job control | |
1104 | stop, unless the kernel predates the TASK_STOPPED / | |
1105 | TASK_TRACED distinction, in which case it might be in a | |
1106 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1107 | can kill it, signal it, et cetera. | |
1108 | ||
1109 | First make sure there is a pending SIGSTOP. Since we are | |
1110 | already attached, the process can not transition from stopped | |
1111 | to running without a PTRACE_CONT; so we know this signal will | |
1112 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1113 | probably already in the queue (unless this kernel is old | |
1114 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1115 | is not an RT signal, it can only be queued once. */ | |
1116 | kill_lwp (pid, SIGSTOP); | |
1117 | ||
1118 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1119 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1120 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1121 | } | |
1122 | ||
1123 | /* Make sure the initial process is stopped. The user-level threads | |
1124 | layer might want to poke around in the inferior, and that won't | |
1125 | work if things haven't stabilized yet. */ | |
1126 | new_pid = my_waitpid (pid, &status, 0); | |
1127 | if (new_pid == -1 && errno == ECHILD) | |
1128 | { | |
1129 | if (first) | |
1130 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1131 | ||
1132 | /* Try again with __WCLONE to check cloned processes. */ | |
1133 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1134 | *cloned = 1; | |
1135 | } | |
1136 | ||
dacc9cb2 PP |
1137 | gdb_assert (pid == new_pid); |
1138 | ||
1139 | if (!WIFSTOPPED (status)) | |
1140 | { | |
1141 | /* The pid we tried to attach has apparently just exited. */ | |
1142 | if (debug_linux_nat) | |
1143 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1144 | pid, status_to_str (status)); | |
1145 | return status; | |
1146 | } | |
a0ef4274 DJ |
1147 | |
1148 | if (WSTOPSIG (status) != SIGSTOP) | |
1149 | { | |
1150 | *signalled = 1; | |
1151 | if (debug_linux_nat) | |
1152 | fprintf_unfiltered (gdb_stdlog, | |
1153 | "LNPAW: Received %s after attaching\n", | |
1154 | status_to_str (status)); | |
1155 | } | |
1156 | ||
1157 | return status; | |
1158 | } | |
1159 | ||
84636d28 PA |
1160 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1161 | the new LWP could not be attached, or 1 if we're already auto | |
1162 | attached to this thread, but haven't processed the | |
1163 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1164 | its existance, without considering it an error. */ | |
d6b0e80f | 1165 | |
9ee57c33 | 1166 | int |
93815fbf | 1167 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1168 | { |
9ee57c33 | 1169 | struct lwp_info *lp; |
84636d28 | 1170 | int lwpid; |
d6b0e80f | 1171 | |
dfd4cc63 | 1172 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1173 | |
9ee57c33 | 1174 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1175 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f AC |
1176 | |
1177 | /* We assume that we're already attached to any LWP that has an id | |
1178 | equal to the overall process id, and to any LWP that is already | |
1179 | in our list of LWPs. If we're not seeing exit events from threads | |
1180 | and we've had PID wraparound since we last tried to stop all threads, | |
1181 | this assumption might be wrong; fortunately, this is very unlikely | |
1182 | to happen. */ | |
dfd4cc63 | 1183 | if (lwpid != ptid_get_pid (ptid) && lp == NULL) |
d6b0e80f | 1184 | { |
a0ef4274 | 1185 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1186 | |
84636d28 | 1187 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1188 | { |
96d7229d | 1189 | if (linux_supports_tracefork ()) |
84636d28 PA |
1190 | { |
1191 | /* If we haven't stopped all threads when we get here, | |
1192 | we may have seen a thread listed in thread_db's list, | |
1193 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1194 | that's the case, ignore this new thread, and let | |
1195 | normal event handling discover it later. */ | |
1196 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1197 | { | |
1198 | /* We've already seen this thread stop, but we | |
1199 | haven't seen the PTRACE_EVENT_CLONE extended | |
1200 | event yet. */ | |
84636d28 PA |
1201 | return 0; |
1202 | } | |
1203 | else | |
1204 | { | |
1205 | int new_pid; | |
1206 | int status; | |
1207 | ||
1208 | /* See if we've got a stop for this new child | |
1209 | pending. If so, we're already attached. */ | |
1210 | new_pid = my_waitpid (lwpid, &status, WNOHANG); | |
1211 | if (new_pid == -1 && errno == ECHILD) | |
1212 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1213 | if (new_pid != -1) | |
1214 | { | |
1215 | if (WIFSTOPPED (status)) | |
1216 | add_to_pid_list (&stopped_pids, lwpid, status); | |
84636d28 PA |
1217 | return 1; |
1218 | } | |
1219 | } | |
1220 | } | |
1221 | ||
9ee57c33 DJ |
1222 | /* If we fail to attach to the thread, issue a warning, |
1223 | but continue. One way this can happen is if thread | |
e9efe249 | 1224 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1225 | bug may place threads in the thread list and then fail |
1226 | to create them. */ | |
1227 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1228 | safe_strerror (errno)); | |
1229 | return -1; | |
1230 | } | |
1231 | ||
d6b0e80f AC |
1232 | if (debug_linux_nat) |
1233 | fprintf_unfiltered (gdb_stdlog, | |
1234 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1235 | target_pid_to_str (ptid)); | |
1236 | ||
a0ef4274 | 1237 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1238 | if (!WIFSTOPPED (status)) |
12696c10 | 1239 | return 1; |
dacc9cb2 | 1240 | |
a0ef4274 DJ |
1241 | lp = add_lwp (ptid); |
1242 | lp->stopped = 1; | |
1243 | lp->cloned = cloned; | |
1244 | lp->signalled = signalled; | |
1245 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1246 | { |
a0ef4274 DJ |
1247 | lp->resumed = 1; |
1248 | lp->status = status; | |
d6b0e80f AC |
1249 | } |
1250 | ||
dfd4cc63 | 1251 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1252 | |
1253 | if (debug_linux_nat) | |
1254 | { | |
1255 | fprintf_unfiltered (gdb_stdlog, | |
1256 | "LLAL: waitpid %s received %s\n", | |
1257 | target_pid_to_str (ptid), | |
1258 | status_to_str (status)); | |
1259 | } | |
1260 | } | |
1261 | else | |
1262 | { | |
1263 | /* We assume that the LWP representing the original process is | |
1264 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1265 | that the GNU/linux ptrace layer uses to keep track of |
1266 | threads. Note that this won't have already been done since | |
1267 | the main thread will have, we assume, been stopped by an | |
1268 | attach from a different layer. */ | |
9ee57c33 DJ |
1269 | if (lp == NULL) |
1270 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1271 | lp->stopped = 1; |
1272 | } | |
9ee57c33 | 1273 | |
25289eb2 | 1274 | lp->last_resume_kind = resume_stop; |
9ee57c33 | 1275 | return 0; |
d6b0e80f AC |
1276 | } |
1277 | ||
b84876c2 | 1278 | static void |
136d6dae VP |
1279 | linux_nat_create_inferior (struct target_ops *ops, |
1280 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1281 | int from_tty) |
1282 | { | |
10568435 JK |
1283 | #ifdef HAVE_PERSONALITY |
1284 | int personality_orig = 0, personality_set = 0; | |
1285 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1286 | |
1287 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1288 | we have to mask the async mode. */ | |
1289 | ||
10568435 JK |
1290 | #ifdef HAVE_PERSONALITY |
1291 | if (disable_randomization) | |
1292 | { | |
1293 | errno = 0; | |
1294 | personality_orig = personality (0xffffffff); | |
1295 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1296 | { | |
1297 | personality_set = 1; | |
1298 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1299 | } | |
1300 | if (errno != 0 || (personality_set | |
1301 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1302 | warning (_("Error disabling address space randomization: %s"), | |
1303 | safe_strerror (errno)); | |
1304 | } | |
1305 | #endif /* HAVE_PERSONALITY */ | |
1306 | ||
2455069d UW |
1307 | /* Make sure we report all signals during startup. */ |
1308 | linux_nat_pass_signals (0, NULL); | |
1309 | ||
136d6dae | 1310 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1311 | |
10568435 JK |
1312 | #ifdef HAVE_PERSONALITY |
1313 | if (personality_set) | |
1314 | { | |
1315 | errno = 0; | |
1316 | personality (personality_orig); | |
1317 | if (errno != 0) | |
1318 | warning (_("Error restoring address space randomization: %s"), | |
1319 | safe_strerror (errno)); | |
1320 | } | |
1321 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1322 | } |
1323 | ||
d6b0e80f | 1324 | static void |
136d6dae | 1325 | linux_nat_attach (struct target_ops *ops, char *args, int from_tty) |
d6b0e80f AC |
1326 | { |
1327 | struct lwp_info *lp; | |
d6b0e80f | 1328 | int status; |
af990527 | 1329 | ptid_t ptid; |
87b0bb13 | 1330 | volatile struct gdb_exception ex; |
d6b0e80f | 1331 | |
2455069d UW |
1332 | /* Make sure we report all signals during attach. */ |
1333 | linux_nat_pass_signals (0, NULL); | |
1334 | ||
87b0bb13 JK |
1335 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
1336 | { | |
1337 | linux_ops->to_attach (ops, args, from_tty); | |
1338 | } | |
1339 | if (ex.reason < 0) | |
1340 | { | |
1341 | pid_t pid = parse_pid_to_attach (args); | |
1342 | struct buffer buffer; | |
1343 | char *message, *buffer_s; | |
1344 | ||
1345 | message = xstrdup (ex.message); | |
1346 | make_cleanup (xfree, message); | |
1347 | ||
1348 | buffer_init (&buffer); | |
1349 | linux_ptrace_attach_warnings (pid, &buffer); | |
1350 | ||
1351 | buffer_grow_str0 (&buffer, ""); | |
1352 | buffer_s = buffer_finish (&buffer); | |
1353 | make_cleanup (xfree, buffer_s); | |
1354 | ||
1355 | throw_error (ex.error, "%s%s", buffer_s, message); | |
1356 | } | |
d6b0e80f | 1357 | |
af990527 PA |
1358 | /* The ptrace base target adds the main thread with (pid,0,0) |
1359 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1360 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1361 | ptid_get_pid (inferior_ptid), | |
1362 | 0); | |
af990527 PA |
1363 | thread_change_ptid (inferior_ptid, ptid); |
1364 | ||
9f0bdab8 | 1365 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1366 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1367 | |
1368 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1369 | &lp->signalled); | |
dacc9cb2 PP |
1370 | if (!WIFSTOPPED (status)) |
1371 | { | |
1372 | if (WIFEXITED (status)) | |
1373 | { | |
1374 | int exit_code = WEXITSTATUS (status); | |
1375 | ||
1376 | target_terminal_ours (); | |
1377 | target_mourn_inferior (); | |
1378 | if (exit_code == 0) | |
1379 | error (_("Unable to attach: program exited normally.")); | |
1380 | else | |
1381 | error (_("Unable to attach: program exited with code %d."), | |
1382 | exit_code); | |
1383 | } | |
1384 | else if (WIFSIGNALED (status)) | |
1385 | { | |
2ea28649 | 1386 | enum gdb_signal signo; |
dacc9cb2 PP |
1387 | |
1388 | target_terminal_ours (); | |
1389 | target_mourn_inferior (); | |
1390 | ||
2ea28649 | 1391 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1392 | error (_("Unable to attach: program terminated with signal " |
1393 | "%s, %s."), | |
2ea28649 PA |
1394 | gdb_signal_to_name (signo), |
1395 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1396 | } |
1397 | ||
1398 | internal_error (__FILE__, __LINE__, | |
1399 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1400 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1401 | } |
1402 | ||
a0ef4274 | 1403 | lp->stopped = 1; |
9f0bdab8 | 1404 | |
a0ef4274 | 1405 | /* Save the wait status to report later. */ |
d6b0e80f | 1406 | lp->resumed = 1; |
a0ef4274 DJ |
1407 | if (debug_linux_nat) |
1408 | fprintf_unfiltered (gdb_stdlog, | |
1409 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1410 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1411 | |
7feb7d06 PA |
1412 | lp->status = status; |
1413 | ||
1414 | if (target_can_async_p ()) | |
1415 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1416 | } |
1417 | ||
a0ef4274 DJ |
1418 | /* Get pending status of LP. */ |
1419 | static int | |
1420 | get_pending_status (struct lwp_info *lp, int *status) | |
1421 | { | |
a493e3e2 | 1422 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1423 | |
1424 | /* If we paused threads momentarily, we may have stored pending | |
1425 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1426 | and GDB core hasn't seen any signal for those threads. | |
1427 | Otherwise, the last signal reported to the core is found in the | |
1428 | thread object's stop_signal. | |
1429 | ||
1430 | There's a corner case that isn't handled here at present. Only | |
1431 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1432 | stop_signal make sense as a real signal to pass to the inferior. | |
1433 | Some catchpoint related events, like | |
1434 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1435 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1436 | those traps are debug API (ptrace in our case) related and |
1437 | induced; the inferior wouldn't see them if it wasn't being | |
1438 | traced. Hence, we should never pass them to the inferior, even | |
1439 | when set to pass state. Since this corner case isn't handled by | |
1440 | infrun.c when proceeding with a signal, for consistency, neither | |
1441 | do we handle it here (or elsewhere in the file we check for | |
1442 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1443 | this is really a corner case. */ | |
1444 | ||
1445 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1446 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1447 | else if (lp->status) |
2ea28649 | 1448 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1449 | else if (non_stop && !is_executing (lp->ptid)) |
1450 | { | |
1451 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1452 | |
16c381f0 | 1453 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1454 | } |
1455 | else if (!non_stop) | |
a0ef4274 | 1456 | { |
ca2163eb PA |
1457 | struct target_waitstatus last; |
1458 | ptid_t last_ptid; | |
4c28f408 | 1459 | |
ca2163eb | 1460 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1461 | |
dfd4cc63 | 1462 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1463 | { |
e09875d4 | 1464 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1465 | |
16c381f0 | 1466 | signo = tp->suspend.stop_signal; |
4c28f408 | 1467 | } |
ca2163eb | 1468 | } |
4c28f408 | 1469 | |
ca2163eb | 1470 | *status = 0; |
4c28f408 | 1471 | |
a493e3e2 | 1472 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1473 | { |
1474 | if (debug_linux_nat) | |
1475 | fprintf_unfiltered (gdb_stdlog, | |
1476 | "GPT: lwp %s has no pending signal\n", | |
1477 | target_pid_to_str (lp->ptid)); | |
1478 | } | |
1479 | else if (!signal_pass_state (signo)) | |
1480 | { | |
1481 | if (debug_linux_nat) | |
3e43a32a MS |
1482 | fprintf_unfiltered (gdb_stdlog, |
1483 | "GPT: lwp %s had signal %s, " | |
1484 | "but it is in no pass state\n", | |
ca2163eb | 1485 | target_pid_to_str (lp->ptid), |
2ea28649 | 1486 | gdb_signal_to_string (signo)); |
a0ef4274 | 1487 | } |
a0ef4274 | 1488 | else |
4c28f408 | 1489 | { |
2ea28649 | 1490 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1491 | |
1492 | if (debug_linux_nat) | |
1493 | fprintf_unfiltered (gdb_stdlog, | |
1494 | "GPT: lwp %s has pending signal %s\n", | |
1495 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1496 | gdb_signal_to_string (signo)); |
4c28f408 | 1497 | } |
a0ef4274 DJ |
1498 | |
1499 | return 0; | |
1500 | } | |
1501 | ||
d6b0e80f AC |
1502 | static int |
1503 | detach_callback (struct lwp_info *lp, void *data) | |
1504 | { | |
1505 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1506 | ||
1507 | if (debug_linux_nat && lp->status) | |
1508 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1509 | strsignal (WSTOPSIG (lp->status)), | |
1510 | target_pid_to_str (lp->ptid)); | |
1511 | ||
a0ef4274 DJ |
1512 | /* If there is a pending SIGSTOP, get rid of it. */ |
1513 | if (lp->signalled) | |
d6b0e80f | 1514 | { |
d6b0e80f AC |
1515 | if (debug_linux_nat) |
1516 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1517 | "DC: Sending SIGCONT to %s\n", |
1518 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1519 | |
dfd4cc63 | 1520 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1521 | lp->signalled = 0; |
d6b0e80f AC |
1522 | } |
1523 | ||
1524 | /* We don't actually detach from the LWP that has an id equal to the | |
1525 | overall process id just yet. */ | |
dfd4cc63 | 1526 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1527 | { |
a0ef4274 DJ |
1528 | int status = 0; |
1529 | ||
1530 | /* Pass on any pending signal for this LWP. */ | |
1531 | get_pending_status (lp, &status); | |
1532 | ||
7b50312a PA |
1533 | if (linux_nat_prepare_to_resume != NULL) |
1534 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1535 | errno = 0; |
dfd4cc63 | 1536 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1537 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1538 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1539 | safe_strerror (errno)); |
1540 | ||
1541 | if (debug_linux_nat) | |
1542 | fprintf_unfiltered (gdb_stdlog, | |
1543 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1544 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1545 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1546 | |
1547 | delete_lwp (lp->ptid); | |
1548 | } | |
1549 | ||
1550 | return 0; | |
1551 | } | |
1552 | ||
1553 | static void | |
52554a0e | 1554 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1555 | { |
b84876c2 | 1556 | int pid; |
a0ef4274 | 1557 | int status; |
d90e17a7 PA |
1558 | struct lwp_info *main_lwp; |
1559 | ||
dfd4cc63 | 1560 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1561 | |
ae5e0686 MK |
1562 | /* Don't unregister from the event loop, as there may be other |
1563 | inferiors running. */ | |
b84876c2 | 1564 | |
4c28f408 PA |
1565 | /* Stop all threads before detaching. ptrace requires that the |
1566 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1567 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1568 | /* ... and wait until all of them have reported back that |
1569 | they're no longer running. */ | |
d90e17a7 | 1570 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1571 | |
d90e17a7 | 1572 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1573 | |
1574 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1575 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1576 | |
1577 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1578 | |
a0ef4274 DJ |
1579 | /* Pass on any pending signal for the last LWP. */ |
1580 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1581 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1582 | && WIFSTOPPED (status)) |
1583 | { | |
52554a0e TT |
1584 | char *tem; |
1585 | ||
a0ef4274 DJ |
1586 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1587 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1588 | tem = alloca (8); |
cde33bf1 | 1589 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1590 | args = tem; |
ddabfc73 TT |
1591 | if (debug_linux_nat) |
1592 | fprintf_unfiltered (gdb_stdlog, | |
1593 | "LND: Sending signal %s to %s\n", | |
1594 | args, | |
1595 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1596 | } |
1597 | ||
7b50312a PA |
1598 | if (linux_nat_prepare_to_resume != NULL) |
1599 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1600 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1601 | |
7a7d3353 PA |
1602 | if (forks_exist_p ()) |
1603 | { | |
1604 | /* Multi-fork case. The current inferior_ptid is being detached | |
1605 | from, but there are other viable forks to debug. Detach from | |
1606 | the current fork, and context-switch to the first | |
1607 | available. */ | |
1608 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1609 | } |
1610 | else | |
1611 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1612 | } |
1613 | ||
1614 | /* Resume LP. */ | |
1615 | ||
25289eb2 | 1616 | static void |
e5ef252a | 1617 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1618 | { |
25289eb2 | 1619 | if (lp->stopped) |
6c95b8df | 1620 | { |
dfd4cc63 | 1621 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
25289eb2 PA |
1622 | |
1623 | if (inf->vfork_child != NULL) | |
1624 | { | |
1625 | if (debug_linux_nat) | |
1626 | fprintf_unfiltered (gdb_stdlog, | |
1627 | "RC: Not resuming %s (vfork parent)\n", | |
1628 | target_pid_to_str (lp->ptid)); | |
1629 | } | |
1630 | else if (lp->status == 0 | |
1631 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
1632 | { | |
1633 | if (debug_linux_nat) | |
1634 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1635 | "RC: Resuming sibling %s, %s, %s\n", |
1636 | target_pid_to_str (lp->ptid), | |
1637 | (signo != GDB_SIGNAL_0 | |
1638 | ? strsignal (gdb_signal_to_host (signo)) | |
1639 | : "0"), | |
1640 | step ? "step" : "resume"); | |
25289eb2 | 1641 | |
7b50312a PA |
1642 | if (linux_nat_prepare_to_resume != NULL) |
1643 | linux_nat_prepare_to_resume (lp); | |
25289eb2 | 1644 | linux_ops->to_resume (linux_ops, |
dfd4cc63 | 1645 | pid_to_ptid (ptid_get_lwp (lp->ptid)), |
e5ef252a | 1646 | step, signo); |
25289eb2 PA |
1647 | lp->stopped = 0; |
1648 | lp->step = step; | |
25289eb2 PA |
1649 | lp->stopped_by_watchpoint = 0; |
1650 | } | |
1651 | else | |
1652 | { | |
1653 | if (debug_linux_nat) | |
1654 | fprintf_unfiltered (gdb_stdlog, | |
1655 | "RC: Not resuming sibling %s (has pending)\n", | |
1656 | target_pid_to_str (lp->ptid)); | |
1657 | } | |
6c95b8df | 1658 | } |
25289eb2 | 1659 | else |
d6b0e80f | 1660 | { |
d90e17a7 PA |
1661 | if (debug_linux_nat) |
1662 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1663 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1664 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1665 | } |
25289eb2 | 1666 | } |
d6b0e80f | 1667 | |
e5ef252a PA |
1668 | /* Resume LWP, with the last stop signal, if it is in pass state. */ |
1669 | ||
25289eb2 | 1670 | static int |
e5ef252a | 1671 | linux_nat_resume_callback (struct lwp_info *lp, void *data) |
25289eb2 | 1672 | { |
e5ef252a PA |
1673 | enum gdb_signal signo = GDB_SIGNAL_0; |
1674 | ||
1675 | if (lp->stopped) | |
1676 | { | |
1677 | struct thread_info *thread; | |
1678 | ||
1679 | thread = find_thread_ptid (lp->ptid); | |
1680 | if (thread != NULL) | |
1681 | { | |
1682 | if (signal_pass_state (thread->suspend.stop_signal)) | |
1683 | signo = thread->suspend.stop_signal; | |
1684 | thread->suspend.stop_signal = GDB_SIGNAL_0; | |
1685 | } | |
1686 | } | |
1687 | ||
1688 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1689 | return 0; |
1690 | } | |
1691 | ||
1692 | static int | |
1693 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1694 | { | |
1695 | lp->resumed = 0; | |
25289eb2 | 1696 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1697 | return 0; |
1698 | } | |
1699 | ||
1700 | static int | |
1701 | resume_set_callback (struct lwp_info *lp, void *data) | |
1702 | { | |
1703 | lp->resumed = 1; | |
25289eb2 | 1704 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1705 | return 0; |
1706 | } | |
1707 | ||
1708 | static void | |
28439f5e | 1709 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1710 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1711 | { |
1712 | struct lwp_info *lp; | |
d90e17a7 | 1713 | int resume_many; |
d6b0e80f | 1714 | |
76f50ad1 DJ |
1715 | if (debug_linux_nat) |
1716 | fprintf_unfiltered (gdb_stdlog, | |
1717 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1718 | step ? "step" : "resume", | |
1719 | target_pid_to_str (ptid), | |
a493e3e2 | 1720 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1721 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1722 | target_pid_to_str (inferior_ptid)); |
1723 | ||
d6b0e80f | 1724 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1725 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1726 | || ptid_is_pid (ptid)); | |
4c28f408 | 1727 | |
e3e9f5a2 PA |
1728 | /* Mark the lwps we're resuming as resumed. */ |
1729 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1730 | |
d90e17a7 PA |
1731 | /* See if it's the current inferior that should be handled |
1732 | specially. */ | |
1733 | if (resume_many) | |
1734 | lp = find_lwp_pid (inferior_ptid); | |
1735 | else | |
1736 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1737 | gdb_assert (lp != NULL); |
d6b0e80f | 1738 | |
9f0bdab8 DJ |
1739 | /* Remember if we're stepping. */ |
1740 | lp->step = step; | |
25289eb2 | 1741 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1742 | |
9f0bdab8 DJ |
1743 | /* If we have a pending wait status for this thread, there is no |
1744 | point in resuming the process. But first make sure that | |
1745 | linux_nat_wait won't preemptively handle the event - we | |
1746 | should never take this short-circuit if we are going to | |
1747 | leave LP running, since we have skipped resuming all the | |
1748 | other threads. This bit of code needs to be synchronized | |
1749 | with linux_nat_wait. */ | |
76f50ad1 | 1750 | |
9f0bdab8 DJ |
1751 | if (lp->status && WIFSTOPPED (lp->status)) |
1752 | { | |
2455069d UW |
1753 | if (!lp->step |
1754 | && WSTOPSIG (lp->status) | |
1755 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1756 | { |
9f0bdab8 DJ |
1757 | if (debug_linux_nat) |
1758 | fprintf_unfiltered (gdb_stdlog, | |
1759 | "LLR: Not short circuiting for ignored " | |
1760 | "status 0x%x\n", lp->status); | |
1761 | ||
d6b0e80f AC |
1762 | /* FIXME: What should we do if we are supposed to continue |
1763 | this thread with a signal? */ | |
a493e3e2 | 1764 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1765 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1766 | lp->status = 0; |
1767 | } | |
1768 | } | |
76f50ad1 | 1769 | |
6c95b8df | 1770 | if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) |
9f0bdab8 DJ |
1771 | { |
1772 | /* FIXME: What should we do if we are supposed to continue | |
1773 | this thread with a signal? */ | |
a493e3e2 | 1774 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1775 | |
9f0bdab8 DJ |
1776 | if (debug_linux_nat) |
1777 | fprintf_unfiltered (gdb_stdlog, | |
1778 | "LLR: Short circuiting for status 0x%x\n", | |
1779 | lp->status); | |
d6b0e80f | 1780 | |
7feb7d06 PA |
1781 | if (target_can_async_p ()) |
1782 | { | |
1783 | target_async (inferior_event_handler, 0); | |
1784 | /* Tell the event loop we have something to process. */ | |
1785 | async_file_mark (); | |
1786 | } | |
9f0bdab8 | 1787 | return; |
d6b0e80f AC |
1788 | } |
1789 | ||
9f0bdab8 | 1790 | /* Mark LWP as not stopped to prevent it from being continued by |
e5ef252a | 1791 | linux_nat_resume_callback. */ |
9f0bdab8 DJ |
1792 | lp->stopped = 0; |
1793 | ||
d90e17a7 | 1794 | if (resume_many) |
e5ef252a | 1795 | iterate_over_lwps (ptid, linux_nat_resume_callback, NULL); |
d90e17a7 PA |
1796 | |
1797 | /* Convert to something the lower layer understands. */ | |
dfd4cc63 | 1798 | ptid = pid_to_ptid (ptid_get_lwp (lp->ptid)); |
d6b0e80f | 1799 | |
7b50312a PA |
1800 | if (linux_nat_prepare_to_resume != NULL) |
1801 | linux_nat_prepare_to_resume (lp); | |
28439f5e | 1802 | linux_ops->to_resume (linux_ops, ptid, step, signo); |
ebec9a0f | 1803 | lp->stopped_by_watchpoint = 0; |
9f0bdab8 | 1804 | |
d6b0e80f AC |
1805 | if (debug_linux_nat) |
1806 | fprintf_unfiltered (gdb_stdlog, | |
1807 | "LLR: %s %s, %s (resume event thread)\n", | |
1808 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1809 | target_pid_to_str (ptid), | |
a493e3e2 | 1810 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1811 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1812 | |
1813 | if (target_can_async_p ()) | |
8ea051c5 | 1814 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1815 | } |
1816 | ||
c5f62d5f | 1817 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1818 | |
1819 | static int | |
1820 | kill_lwp (int lwpid, int signo) | |
1821 | { | |
c5f62d5f DE |
1822 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1823 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1824 | |
1825 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1826 | { |
1827 | static int tkill_failed; | |
1828 | ||
1829 | if (!tkill_failed) | |
1830 | { | |
1831 | int ret; | |
1832 | ||
1833 | errno = 0; | |
1834 | ret = syscall (__NR_tkill, lwpid, signo); | |
1835 | if (errno != ENOSYS) | |
1836 | return ret; | |
1837 | tkill_failed = 1; | |
1838 | } | |
1839 | } | |
d6b0e80f AC |
1840 | #endif |
1841 | ||
1842 | return kill (lwpid, signo); | |
1843 | } | |
1844 | ||
ca2163eb PA |
1845 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1846 | event, check if the core is interested in it: if not, ignore the | |
1847 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1848 | syscall entry/exit status, since the ptrace event itself doesn't | |
1849 | indicate it, and report the trap to higher layers. */ | |
1850 | ||
1851 | static int | |
1852 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1853 | { | |
1854 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1855 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1856 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1857 | ||
1858 | if (stopping) | |
1859 | { | |
1860 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1861 | makes it so that the LWP reports an immediate syscall return, | |
1862 | followed by the SIGSTOP. Skip seeing that "return" using | |
1863 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1864 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1865 | entry event. If we didn't do this (and returned 0), we'd | |
1866 | leave a syscall entry pending, and our caller, by using | |
1867 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1868 | itself. Later, when the user re-resumes this LWP, we'd see | |
1869 | another syscall entry event and we'd mistake it for a return. | |
1870 | ||
1871 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1872 | (leaving immediately with LWP->signalled set, without issuing | |
1873 | a PTRACE_CONT), it would still be problematic to leave this | |
1874 | syscall enter pending, as later when the thread is resumed, | |
1875 | it would then see the same syscall exit mentioned above, | |
1876 | followed by the delayed SIGSTOP, while the syscall didn't | |
1877 | actually get to execute. It seems it would be even more | |
1878 | confusing to the user. */ | |
1879 | ||
1880 | if (debug_linux_nat) | |
1881 | fprintf_unfiltered (gdb_stdlog, | |
1882 | "LHST: ignoring syscall %d " | |
1883 | "for LWP %ld (stopping threads), " | |
1884 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1885 | syscall_number, | |
dfd4cc63 | 1886 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1887 | |
1888 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1889 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
ca2163eb PA |
1890 | return 1; |
1891 | } | |
1892 | ||
1893 | if (catch_syscall_enabled ()) | |
1894 | { | |
1895 | /* Always update the entry/return state, even if this particular | |
1896 | syscall isn't interesting to the core now. In async mode, | |
1897 | the user could install a new catchpoint for this syscall | |
1898 | between syscall enter/return, and we'll need to know to | |
1899 | report a syscall return if that happens. */ | |
1900 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1901 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1902 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1903 | ||
1904 | if (catching_syscall_number (syscall_number)) | |
1905 | { | |
1906 | /* Alright, an event to report. */ | |
1907 | ourstatus->kind = lp->syscall_state; | |
1908 | ourstatus->value.syscall_number = syscall_number; | |
1909 | ||
1910 | if (debug_linux_nat) | |
1911 | fprintf_unfiltered (gdb_stdlog, | |
1912 | "LHST: stopping for %s of syscall %d" | |
1913 | " for LWP %ld\n", | |
3e43a32a MS |
1914 | lp->syscall_state |
1915 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1916 | ? "entry" : "return", |
1917 | syscall_number, | |
dfd4cc63 | 1918 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1919 | return 0; |
1920 | } | |
1921 | ||
1922 | if (debug_linux_nat) | |
1923 | fprintf_unfiltered (gdb_stdlog, | |
1924 | "LHST: ignoring %s of syscall %d " | |
1925 | "for LWP %ld\n", | |
1926 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1927 | ? "entry" : "return", | |
1928 | syscall_number, | |
dfd4cc63 | 1929 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1930 | } |
1931 | else | |
1932 | { | |
1933 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1934 | before on this LWP, it could happen that the user removes all | |
1935 | syscall catchpoints before we get to process this event. | |
1936 | There are two noteworthy issues here: | |
1937 | ||
1938 | - When stopped at a syscall entry event, resuming with | |
1939 | PT_STEP still resumes executing the syscall and reports a | |
1940 | syscall return. | |
1941 | ||
1942 | - Only PT_SYSCALL catches syscall enters. If we last | |
1943 | single-stepped this thread, then this event can't be a | |
1944 | syscall enter. If we last single-stepped this thread, this | |
1945 | has to be a syscall exit. | |
1946 | ||
1947 | The points above mean that the next resume, be it PT_STEP or | |
1948 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1949 | if (debug_linux_nat) | |
1950 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1951 | "LHST: caught syscall event " |
1952 | "with no syscall catchpoints." | |
ca2163eb PA |
1953 | " %d for LWP %ld, ignoring\n", |
1954 | syscall_number, | |
dfd4cc63 | 1955 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1956 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1957 | } | |
1958 | ||
1959 | /* The core isn't interested in this event. For efficiency, avoid | |
1960 | stopping all threads only to have the core resume them all again. | |
1961 | Since we're not stopping threads, if we're still syscall tracing | |
1962 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1963 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1964 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1965 | ||
1966 | /* Note that gdbarch_get_syscall_number may access registers, hence | |
1967 | fill a regcache. */ | |
1968 | registers_changed (); | |
7b50312a PA |
1969 | if (linux_nat_prepare_to_resume != NULL) |
1970 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 1971 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 1972 | lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1973 | return 1; |
1974 | } | |
1975 | ||
3d799a95 DJ |
1976 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1977 | event, we need to add the new LWP to our list (and not report the | |
1978 | trap to higher layers). This function returns non-zero if the | |
1979 | event should be ignored and we should wait again. If STOPPING is | |
1980 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1981 | |
1982 | static int | |
3d799a95 DJ |
1983 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1984 | int stopping) | |
d6b0e80f | 1985 | { |
dfd4cc63 | 1986 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1987 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
3d799a95 | 1988 | int event = status >> 16; |
d6b0e80f | 1989 | |
3d799a95 DJ |
1990 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1991 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1992 | { |
3d799a95 DJ |
1993 | unsigned long new_pid; |
1994 | int ret; | |
1995 | ||
1996 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1997 | |
3d799a95 DJ |
1998 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1999 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2000 | { | |
2001 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2002 | hits the SIGSTOP, but we're already attached. */ | |
2003 | ret = my_waitpid (new_pid, &status, | |
2004 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2005 | if (ret == -1) | |
2006 | perror_with_name (_("waiting for new child")); | |
2007 | else if (ret != new_pid) | |
2008 | internal_error (__FILE__, __LINE__, | |
2009 | _("wait returned unexpected PID %d"), ret); | |
2010 | else if (!WIFSTOPPED (status)) | |
2011 | internal_error (__FILE__, __LINE__, | |
2012 | _("wait returned unexpected status 0x%x"), status); | |
2013 | } | |
2014 | ||
3a3e9ee3 | 2015 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2016 | |
26cb8b7c PA |
2017 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2018 | { | |
2019 | /* The arch-specific native code may need to know about new | |
2020 | forks even if those end up never mapped to an | |
2021 | inferior. */ | |
2022 | if (linux_nat_new_fork != NULL) | |
2023 | linux_nat_new_fork (lp, new_pid); | |
2024 | } | |
2025 | ||
2277426b | 2026 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2027 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2028 | { |
2277426b PA |
2029 | /* Handle checkpointing by linux-fork.c here as a special |
2030 | case. We don't want the follow-fork-mode or 'catch fork' | |
2031 | to interfere with this. */ | |
2032 | ||
2033 | /* This won't actually modify the breakpoint list, but will | |
2034 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2035 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2036 | |
2037 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2038 | if (!find_fork_pid (new_pid)) |
2039 | add_fork (new_pid); | |
2277426b PA |
2040 | |
2041 | /* Report as spurious, so that infrun doesn't want to follow | |
2042 | this fork. We're actually doing an infcall in | |
2043 | linux-fork.c. */ | |
2044 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2045 | |
2046 | /* Report the stop to the core. */ | |
2047 | return 0; | |
2048 | } | |
2049 | ||
3d799a95 DJ |
2050 | if (event == PTRACE_EVENT_FORK) |
2051 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2052 | else if (event == PTRACE_EVENT_VFORK) | |
2053 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2054 | else |
3d799a95 | 2055 | { |
78768c4a JK |
2056 | struct lwp_info *new_lp; |
2057 | ||
3d799a95 | 2058 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2059 | |
3c4d7e12 PA |
2060 | if (debug_linux_nat) |
2061 | fprintf_unfiltered (gdb_stdlog, | |
2062 | "LHEW: Got clone event " | |
2063 | "from LWP %d, new child is LWP %ld\n", | |
2064 | pid, new_pid); | |
2065 | ||
dfd4cc63 | 2066 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2067 | new_lp->cloned = 1; |
4c28f408 | 2068 | new_lp->stopped = 1; |
d6b0e80f | 2069 | |
3d799a95 DJ |
2070 | if (WSTOPSIG (status) != SIGSTOP) |
2071 | { | |
2072 | /* This can happen if someone starts sending signals to | |
2073 | the new thread before it gets a chance to run, which | |
2074 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2075 | This is an unlikely case, and harder to handle for | |
2076 | fork / vfork than for clone, so we do not try - but | |
2077 | we handle it for clone events here. We'll send | |
2078 | the other signal on to the thread below. */ | |
2079 | ||
2080 | new_lp->signalled = 1; | |
2081 | } | |
2082 | else | |
79395f92 PA |
2083 | { |
2084 | struct thread_info *tp; | |
2085 | ||
2086 | /* When we stop for an event in some other thread, and | |
2087 | pull the thread list just as this thread has cloned, | |
2088 | we'll have seen the new thread in the thread_db list | |
2089 | before handling the CLONE event (glibc's | |
2090 | pthread_create adds the new thread to the thread list | |
2091 | before clone'ing, and has the kernel fill in the | |
2092 | thread's tid on the clone call with | |
2093 | CLONE_PARENT_SETTID). If that happened, and the core | |
2094 | had requested the new thread to stop, we'll have | |
2095 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2096 | RT signal, it can only be queued once. We need to be | |
2097 | careful to not resume the LWP if we wanted it to | |
2098 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2099 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2100 | tp = find_thread_ptid (new_lp->ptid); |
2101 | if (tp != NULL && tp->stop_requested) | |
2102 | new_lp->last_resume_kind = resume_stop; | |
2103 | else | |
2104 | status = 0; | |
2105 | } | |
d6b0e80f | 2106 | |
4c28f408 | 2107 | if (non_stop) |
3d799a95 | 2108 | { |
4c28f408 PA |
2109 | /* Add the new thread to GDB's lists as soon as possible |
2110 | so that: | |
2111 | ||
2112 | 1) the frontend doesn't have to wait for a stop to | |
2113 | display them, and, | |
2114 | ||
2115 | 2) we tag it with the correct running state. */ | |
2116 | ||
2117 | /* If the thread_db layer is active, let it know about | |
2118 | this new thread, and add it to GDB's list. */ | |
2119 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
2120 | { | |
2121 | /* We're not using thread_db. Add it to GDB's | |
2122 | list. */ | |
dfd4cc63 | 2123 | target_post_attach (ptid_get_lwp (new_lp->ptid)); |
4c28f408 PA |
2124 | add_thread (new_lp->ptid); |
2125 | } | |
2126 | ||
2127 | if (!stopping) | |
2128 | { | |
2129 | set_running (new_lp->ptid, 1); | |
2130 | set_executing (new_lp->ptid, 1); | |
e21ffe51 PA |
2131 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced |
2132 | resume_stop. */ | |
2133 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2134 | } |
2135 | } | |
2136 | ||
79395f92 PA |
2137 | if (status != 0) |
2138 | { | |
2139 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2140 | gdb_assert (new_lp->status == 0); | |
2141 | ||
2142 | /* Save the wait status to report later. */ | |
2143 | if (debug_linux_nat) | |
2144 | fprintf_unfiltered (gdb_stdlog, | |
2145 | "LHEW: waitpid of new LWP %ld, " | |
2146 | "saving status %s\n", | |
dfd4cc63 | 2147 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2148 | status_to_str (status)); |
2149 | new_lp->status = status; | |
2150 | } | |
2151 | ||
ca2163eb PA |
2152 | /* Note the need to use the low target ops to resume, to |
2153 | handle resuming with PT_SYSCALL if we have syscall | |
2154 | catchpoints. */ | |
4c28f408 PA |
2155 | if (!stopping) |
2156 | { | |
3d799a95 | 2157 | new_lp->resumed = 1; |
ca2163eb | 2158 | |
79395f92 | 2159 | if (status == 0) |
ad34eb2f | 2160 | { |
e21ffe51 | 2161 | gdb_assert (new_lp->last_resume_kind == resume_continue); |
ad34eb2f JK |
2162 | if (debug_linux_nat) |
2163 | fprintf_unfiltered (gdb_stdlog, | |
79395f92 | 2164 | "LHEW: resuming new LWP %ld\n", |
dfd4cc63 | 2165 | ptid_get_lwp (new_lp->ptid)); |
7b50312a PA |
2166 | if (linux_nat_prepare_to_resume != NULL) |
2167 | linux_nat_prepare_to_resume (new_lp); | |
79395f92 | 2168 | linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid), |
a493e3e2 | 2169 | 0, GDB_SIGNAL_0); |
79395f92 | 2170 | new_lp->stopped = 0; |
ad34eb2f JK |
2171 | } |
2172 | } | |
d6b0e80f | 2173 | |
3d799a95 DJ |
2174 | if (debug_linux_nat) |
2175 | fprintf_unfiltered (gdb_stdlog, | |
3c4d7e12 | 2176 | "LHEW: resuming parent LWP %d\n", pid); |
7b50312a PA |
2177 | if (linux_nat_prepare_to_resume != NULL) |
2178 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
2179 | linux_ops->to_resume (linux_ops, |
2180 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
a493e3e2 | 2181 | 0, GDB_SIGNAL_0); |
3d799a95 DJ |
2182 | |
2183 | return 1; | |
2184 | } | |
2185 | ||
2186 | return 0; | |
d6b0e80f AC |
2187 | } |
2188 | ||
3d799a95 DJ |
2189 | if (event == PTRACE_EVENT_EXEC) |
2190 | { | |
a75724bc PA |
2191 | if (debug_linux_nat) |
2192 | fprintf_unfiltered (gdb_stdlog, | |
2193 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2194 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2195 | |
3d799a95 DJ |
2196 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2197 | ourstatus->value.execd_pathname | |
6d8fd2b7 | 2198 | = xstrdup (linux_child_pid_to_exec_file (pid)); |
3d799a95 | 2199 | |
6c95b8df PA |
2200 | return 0; |
2201 | } | |
2202 | ||
2203 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2204 | { | |
2205 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2206 | { |
6c95b8df | 2207 | if (debug_linux_nat) |
3e43a32a MS |
2208 | fprintf_unfiltered (gdb_stdlog, |
2209 | "LHEW: Got expected PTRACE_EVENT_" | |
2210 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2211 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2212 | |
6c95b8df PA |
2213 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2214 | return 0; | |
3d799a95 DJ |
2215 | } |
2216 | ||
6c95b8df | 2217 | if (debug_linux_nat) |
3e43a32a MS |
2218 | fprintf_unfiltered (gdb_stdlog, |
2219 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
2220 | "from LWP %ld: resuming\n", | |
dfd4cc63 LM |
2221 | ptid_get_lwp (lp->ptid)); |
2222 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); | |
6c95b8df | 2223 | return 1; |
3d799a95 DJ |
2224 | } |
2225 | ||
2226 | internal_error (__FILE__, __LINE__, | |
2227 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2228 | } |
2229 | ||
2230 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2231 | exited. */ | |
2232 | ||
2233 | static int | |
2234 | wait_lwp (struct lwp_info *lp) | |
2235 | { | |
2236 | pid_t pid; | |
432b4d03 | 2237 | int status = 0; |
d6b0e80f | 2238 | int thread_dead = 0; |
432b4d03 | 2239 | sigset_t prev_mask; |
d6b0e80f AC |
2240 | |
2241 | gdb_assert (!lp->stopped); | |
2242 | gdb_assert (lp->status == 0); | |
2243 | ||
432b4d03 JK |
2244 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2245 | block_child_signals (&prev_mask); | |
2246 | ||
2247 | for (;;) | |
d6b0e80f | 2248 | { |
432b4d03 JK |
2249 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2250 | was right and we should just call sigsuspend. */ | |
2251 | ||
dfd4cc63 | 2252 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2253 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2254 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2255 | if (pid == -1 && errno == ECHILD) |
2256 | { | |
2257 | /* The thread has previously exited. We need to delete it | |
2258 | now because, for some vendor 2.4 kernels with NPTL | |
2259 | support backported, there won't be an exit event unless | |
2260 | it is the main thread. 2.6 kernels will report an exit | |
2261 | event for each thread that exits, as expected. */ | |
2262 | thread_dead = 1; | |
2263 | if (debug_linux_nat) | |
2264 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2265 | target_pid_to_str (lp->ptid)); | |
2266 | } | |
432b4d03 JK |
2267 | if (pid != 0) |
2268 | break; | |
2269 | ||
2270 | /* Bugs 10970, 12702. | |
2271 | Thread group leader may have exited in which case we'll lock up in | |
2272 | waitpid if there are other threads, even if they are all zombies too. | |
2273 | Basically, we're not supposed to use waitpid this way. | |
2274 | __WCLONE is not applicable for the leader so we can't use that. | |
2275 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2276 | process; it gets ESRCH both for the zombie and for running processes. | |
2277 | ||
2278 | As a workaround, check if we're waiting for the thread group leader and | |
2279 | if it's a zombie, and avoid calling waitpid if it is. | |
2280 | ||
2281 | This is racy, what if the tgl becomes a zombie right after we check? | |
2282 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2283 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2284 | |
dfd4cc63 LM |
2285 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2286 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2287 | { |
d6b0e80f AC |
2288 | thread_dead = 1; |
2289 | if (debug_linux_nat) | |
432b4d03 JK |
2290 | fprintf_unfiltered (gdb_stdlog, |
2291 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2292 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2293 | break; |
d6b0e80f | 2294 | } |
432b4d03 JK |
2295 | |
2296 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2297 | get invoked despite our caller had them intentionally blocked by | |
2298 | block_child_signals. This is sensitive only to the loop of | |
2299 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2300 | again before it gets to sigsuspend so we can safely let the handlers | |
2301 | get executed here. */ | |
2302 | ||
2303 | sigsuspend (&suspend_mask); | |
2304 | } | |
2305 | ||
2306 | restore_child_signals_mask (&prev_mask); | |
2307 | ||
d6b0e80f AC |
2308 | if (!thread_dead) |
2309 | { | |
dfd4cc63 | 2310 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2311 | |
2312 | if (debug_linux_nat) | |
2313 | { | |
2314 | fprintf_unfiltered (gdb_stdlog, | |
2315 | "WL: waitpid %s received %s\n", | |
2316 | target_pid_to_str (lp->ptid), | |
2317 | status_to_str (status)); | |
2318 | } | |
d6b0e80f | 2319 | |
a9f4bb21 PA |
2320 | /* Check if the thread has exited. */ |
2321 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2322 | { | |
2323 | thread_dead = 1; | |
2324 | if (debug_linux_nat) | |
2325 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2326 | target_pid_to_str (lp->ptid)); | |
2327 | } | |
d6b0e80f AC |
2328 | } |
2329 | ||
2330 | if (thread_dead) | |
2331 | { | |
e26af52f | 2332 | exit_lwp (lp); |
d6b0e80f AC |
2333 | return 0; |
2334 | } | |
2335 | ||
2336 | gdb_assert (WIFSTOPPED (status)); | |
2337 | ||
ca2163eb PA |
2338 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2339 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2340 | { | |
2341 | /* No longer need the sysgood bit. The ptrace event ends up | |
2342 | recorded in lp->waitstatus if we care for it. We can carry | |
2343 | on handling the event like a regular SIGTRAP from here | |
2344 | on. */ | |
2345 | status = W_STOPCODE (SIGTRAP); | |
2346 | if (linux_handle_syscall_trap (lp, 1)) | |
2347 | return wait_lwp (lp); | |
2348 | } | |
2349 | ||
d6b0e80f AC |
2350 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2351 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2352 | { | |
2353 | if (debug_linux_nat) | |
2354 | fprintf_unfiltered (gdb_stdlog, | |
2355 | "WL: Handling extended status 0x%06x\n", | |
2356 | status); | |
3d799a95 | 2357 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
2358 | return wait_lwp (lp); |
2359 | } | |
2360 | ||
2361 | return status; | |
2362 | } | |
2363 | ||
2364 | /* Send a SIGSTOP to LP. */ | |
2365 | ||
2366 | static int | |
2367 | stop_callback (struct lwp_info *lp, void *data) | |
2368 | { | |
2369 | if (!lp->stopped && !lp->signalled) | |
2370 | { | |
2371 | int ret; | |
2372 | ||
2373 | if (debug_linux_nat) | |
2374 | { | |
2375 | fprintf_unfiltered (gdb_stdlog, | |
2376 | "SC: kill %s **<SIGSTOP>**\n", | |
2377 | target_pid_to_str (lp->ptid)); | |
2378 | } | |
2379 | errno = 0; | |
dfd4cc63 | 2380 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2381 | if (debug_linux_nat) |
2382 | { | |
2383 | fprintf_unfiltered (gdb_stdlog, | |
2384 | "SC: lwp kill %d %s\n", | |
2385 | ret, | |
2386 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2387 | } | |
2388 | ||
2389 | lp->signalled = 1; | |
2390 | gdb_assert (lp->status == 0); | |
2391 | } | |
2392 | ||
2393 | return 0; | |
2394 | } | |
2395 | ||
7b50312a PA |
2396 | /* Request a stop on LWP. */ |
2397 | ||
2398 | void | |
2399 | linux_stop_lwp (struct lwp_info *lwp) | |
2400 | { | |
2401 | stop_callback (lwp, NULL); | |
2402 | } | |
2403 | ||
57380f4e | 2404 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2405 | |
2406 | static int | |
57380f4e DJ |
2407 | linux_nat_has_pending_sigint (int pid) |
2408 | { | |
2409 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2410 | |
2411 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2412 | ||
2413 | if (sigismember (&pending, SIGINT) | |
2414 | && !sigismember (&ignored, SIGINT)) | |
2415 | return 1; | |
2416 | ||
2417 | return 0; | |
2418 | } | |
2419 | ||
2420 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2421 | ||
2422 | static int | |
2423 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2424 | { |
57380f4e DJ |
2425 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2426 | flag to consume the next one. */ | |
2427 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2428 | && WSTOPSIG (lp->status) == SIGINT) | |
2429 | lp->status = 0; | |
2430 | else | |
2431 | lp->ignore_sigint = 1; | |
2432 | ||
2433 | return 0; | |
2434 | } | |
2435 | ||
2436 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2437 | This function is called after we know the LWP has stopped; if the LWP | |
2438 | stopped before the expected SIGINT was delivered, then it will never have | |
2439 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2440 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2441 | |
57380f4e DJ |
2442 | static void |
2443 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2444 | { | |
2445 | if (!lp->ignore_sigint) | |
2446 | return; | |
2447 | ||
dfd4cc63 | 2448 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2449 | { |
2450 | if (debug_linux_nat) | |
2451 | fprintf_unfiltered (gdb_stdlog, | |
2452 | "MCIS: Clearing bogus flag for %s\n", | |
2453 | target_pid_to_str (lp->ptid)); | |
2454 | lp->ignore_sigint = 0; | |
2455 | } | |
2456 | } | |
2457 | ||
ebec9a0f PA |
2458 | /* Fetch the possible triggered data watchpoint info and store it in |
2459 | LP. | |
2460 | ||
2461 | On some archs, like x86, that use debug registers to set | |
2462 | watchpoints, it's possible that the way to know which watched | |
2463 | address trapped, is to check the register that is used to select | |
2464 | which address to watch. Problem is, between setting the watchpoint | |
2465 | and reading back which data address trapped, the user may change | |
2466 | the set of watchpoints, and, as a consequence, GDB changes the | |
2467 | debug registers in the inferior. To avoid reading back a stale | |
2468 | stopped-data-address when that happens, we cache in LP the fact | |
2469 | that a watchpoint trapped, and the corresponding data address, as | |
2470 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2471 | registers meanwhile, we have the cached data we can rely on. */ | |
2472 | ||
2473 | static void | |
2474 | save_sigtrap (struct lwp_info *lp) | |
2475 | { | |
2476 | struct cleanup *old_chain; | |
2477 | ||
2478 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
2479 | { | |
2480 | lp->stopped_by_watchpoint = 0; | |
2481 | return; | |
2482 | } | |
2483 | ||
2484 | old_chain = save_inferior_ptid (); | |
2485 | inferior_ptid = lp->ptid; | |
2486 | ||
2487 | lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint (); | |
2488 | ||
2489 | if (lp->stopped_by_watchpoint) | |
2490 | { | |
2491 | if (linux_ops->to_stopped_data_address != NULL) | |
2492 | lp->stopped_data_address_p = | |
2493 | linux_ops->to_stopped_data_address (¤t_target, | |
2494 | &lp->stopped_data_address); | |
2495 | else | |
2496 | lp->stopped_data_address_p = 0; | |
2497 | } | |
2498 | ||
2499 | do_cleanups (old_chain); | |
2500 | } | |
2501 | ||
2502 | /* See save_sigtrap. */ | |
2503 | ||
2504 | static int | |
2505 | linux_nat_stopped_by_watchpoint (void) | |
2506 | { | |
2507 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2508 | ||
2509 | gdb_assert (lp != NULL); | |
2510 | ||
2511 | return lp->stopped_by_watchpoint; | |
2512 | } | |
2513 | ||
2514 | static int | |
2515 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2516 | { | |
2517 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2518 | ||
2519 | gdb_assert (lp != NULL); | |
2520 | ||
2521 | *addr_p = lp->stopped_data_address; | |
2522 | ||
2523 | return lp->stopped_data_address_p; | |
2524 | } | |
2525 | ||
26ab7092 JK |
2526 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2527 | ||
2528 | static int | |
2529 | sigtrap_is_event (int status) | |
2530 | { | |
2531 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2532 | } | |
2533 | ||
2534 | /* SIGTRAP-like events recognizer. */ | |
2535 | ||
2536 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
2537 | ||
00390b84 JK |
2538 | /* Check for SIGTRAP-like events in LP. */ |
2539 | ||
2540 | static int | |
2541 | linux_nat_lp_status_is_event (struct lwp_info *lp) | |
2542 | { | |
2543 | /* We check for lp->waitstatus in addition to lp->status, because we can | |
2544 | have pending process exits recorded in lp->status | |
2545 | and W_EXITCODE(0,0) == 0. We should probably have an additional | |
2546 | lp->status_p flag. */ | |
2547 | ||
2548 | return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE | |
2549 | && linux_nat_status_is_event (lp->status)); | |
2550 | } | |
2551 | ||
26ab7092 JK |
2552 | /* Set alternative SIGTRAP-like events recognizer. If |
2553 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2554 | applied. */ | |
2555 | ||
2556 | void | |
2557 | linux_nat_set_status_is_event (struct target_ops *t, | |
2558 | int (*status_is_event) (int status)) | |
2559 | { | |
2560 | linux_nat_status_is_event = status_is_event; | |
2561 | } | |
2562 | ||
57380f4e DJ |
2563 | /* Wait until LP is stopped. */ |
2564 | ||
2565 | static int | |
2566 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2567 | { | |
dfd4cc63 | 2568 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
6c95b8df PA |
2569 | |
2570 | /* If this is a vfork parent, bail out, it is not going to report | |
2571 | any SIGSTOP until the vfork is done with. */ | |
2572 | if (inf->vfork_child != NULL) | |
2573 | return 0; | |
2574 | ||
d6b0e80f AC |
2575 | if (!lp->stopped) |
2576 | { | |
2577 | int status; | |
2578 | ||
2579 | status = wait_lwp (lp); | |
2580 | if (status == 0) | |
2581 | return 0; | |
2582 | ||
57380f4e DJ |
2583 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2584 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2585 | { |
57380f4e | 2586 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2587 | |
2588 | errno = 0; | |
dfd4cc63 | 2589 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f AC |
2590 | if (debug_linux_nat) |
2591 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2592 | "PTRACE_CONT %s, 0, 0 (%s) " |
2593 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2594 | target_pid_to_str (lp->ptid), |
2595 | errno ? safe_strerror (errno) : "OK"); | |
2596 | ||
57380f4e | 2597 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2598 | } |
2599 | ||
57380f4e DJ |
2600 | maybe_clear_ignore_sigint (lp); |
2601 | ||
d6b0e80f AC |
2602 | if (WSTOPSIG (status) != SIGSTOP) |
2603 | { | |
e5ef252a | 2604 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2605 | |
e5ef252a PA |
2606 | save_sigtrap (lp); |
2607 | ||
2608 | if (debug_linux_nat) | |
2609 | fprintf_unfiltered (gdb_stdlog, | |
2610 | "SWC: Pending event %s in %s\n", | |
2611 | status_to_str ((int) status), | |
2612 | target_pid_to_str (lp->ptid)); | |
2613 | ||
2614 | /* Save the sigtrap event. */ | |
2615 | lp->status = status; | |
2616 | gdb_assert (!lp->stopped); | |
2617 | gdb_assert (lp->signalled); | |
2618 | lp->stopped = 1; | |
d6b0e80f AC |
2619 | } |
2620 | else | |
2621 | { | |
2622 | /* We caught the SIGSTOP that we intended to catch, so | |
2623 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2624 | |
2625 | if (debug_linux_nat) | |
2626 | fprintf_unfiltered (gdb_stdlog, | |
2627 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2628 | target_pid_to_str (lp->ptid)); | |
2629 | ||
d6b0e80f | 2630 | lp->stopped = 1; |
e5ef252a PA |
2631 | |
2632 | /* Reset SIGNALLED only after the stop_wait_callback call | |
2633 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2634 | lp->signalled = 0; |
2635 | } | |
2636 | } | |
2637 | ||
2638 | return 0; | |
2639 | } | |
2640 | ||
d6b0e80f AC |
2641 | /* Return non-zero if LP has a wait status pending. */ |
2642 | ||
2643 | static int | |
2644 | status_callback (struct lwp_info *lp, void *data) | |
2645 | { | |
2646 | /* Only report a pending wait status if we pretend that this has | |
2647 | indeed been resumed. */ | |
ca2163eb PA |
2648 | if (!lp->resumed) |
2649 | return 0; | |
2650 | ||
2651 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2652 | { | |
2653 | /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event, | |
766062f6 | 2654 | or a pending process exit. Note that `W_EXITCODE(0,0) == |
ca2163eb PA |
2655 | 0', so a clean process exit can not be stored pending in |
2656 | lp->status, it is indistinguishable from | |
2657 | no-pending-status. */ | |
2658 | return 1; | |
2659 | } | |
2660 | ||
2661 | if (lp->status != 0) | |
2662 | return 1; | |
2663 | ||
2664 | return 0; | |
d6b0e80f AC |
2665 | } |
2666 | ||
2667 | /* Return non-zero if LP isn't stopped. */ | |
2668 | ||
2669 | static int | |
2670 | running_callback (struct lwp_info *lp, void *data) | |
2671 | { | |
25289eb2 PA |
2672 | return (!lp->stopped |
2673 | || ((lp->status != 0 | |
2674 | || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2675 | && lp->resumed)); | |
d6b0e80f AC |
2676 | } |
2677 | ||
2678 | /* Count the LWP's that have had events. */ | |
2679 | ||
2680 | static int | |
2681 | count_events_callback (struct lwp_info *lp, void *data) | |
2682 | { | |
2683 | int *count = data; | |
2684 | ||
2685 | gdb_assert (count != NULL); | |
2686 | ||
e09490f1 | 2687 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2688 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2689 | (*count)++; |
2690 | ||
2691 | return 0; | |
2692 | } | |
2693 | ||
2694 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2695 | ||
2696 | static int | |
2697 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2698 | { | |
25289eb2 PA |
2699 | if (lp->last_resume_kind == resume_step |
2700 | && lp->status != 0) | |
d6b0e80f AC |
2701 | return 1; |
2702 | else | |
2703 | return 0; | |
2704 | } | |
2705 | ||
2706 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2707 | ||
2708 | static int | |
2709 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2710 | { | |
2711 | int *selector = data; | |
2712 | ||
2713 | gdb_assert (selector != NULL); | |
2714 | ||
1777feb0 | 2715 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2716 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2717 | if ((*selector)-- == 0) |
2718 | return 1; | |
2719 | ||
2720 | return 0; | |
2721 | } | |
2722 | ||
710151dd PA |
2723 | static int |
2724 | cancel_breakpoint (struct lwp_info *lp) | |
2725 | { | |
2726 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2727 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2728 | LWP. We will handle the current event, eventually we will resume | |
2729 | this LWP, and this breakpoint will trap again. | |
2730 | ||
2731 | If we do not do this, then we run the risk that the user will | |
2732 | delete or disable the breakpoint, but the LWP will have already | |
2733 | tripped on it. */ | |
2734 | ||
515630c5 UW |
2735 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2736 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2737 | CORE_ADDR pc; | |
2738 | ||
118e6252 | 2739 | pc = regcache_read_pc (regcache) - target_decr_pc_after_break (gdbarch); |
6c95b8df | 2740 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
710151dd PA |
2741 | { |
2742 | if (debug_linux_nat) | |
2743 | fprintf_unfiltered (gdb_stdlog, | |
2744 | "CB: Push back breakpoint for %s\n", | |
2745 | target_pid_to_str (lp->ptid)); | |
2746 | ||
2747 | /* Back up the PC if necessary. */ | |
118e6252 | 2748 | if (target_decr_pc_after_break (gdbarch)) |
515630c5 UW |
2749 | regcache_write_pc (regcache, pc); |
2750 | ||
710151dd PA |
2751 | return 1; |
2752 | } | |
2753 | return 0; | |
2754 | } | |
2755 | ||
d6b0e80f AC |
2756 | static int |
2757 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2758 | { | |
2759 | struct lwp_info *event_lp = data; | |
2760 | ||
2761 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2762 | if (lp == event_lp) | |
2763 | return 0; | |
2764 | ||
2765 | /* If a LWP other than the LWP that we're reporting an event for has | |
2766 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2767 | then just arrange for it to hit it again later. We don't keep | |
2768 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2769 | LWP. We will handle the current event, eventually we will resume | |
2770 | all LWPs, and this one will get its breakpoint trap again. | |
2771 | ||
2772 | If we do not do this, then we run the risk that the user will | |
2773 | delete or disable the breakpoint, but the LWP will have already | |
2774 | tripped on it. */ | |
2775 | ||
00390b84 | 2776 | if (linux_nat_lp_status_is_event (lp) |
710151dd PA |
2777 | && cancel_breakpoint (lp)) |
2778 | /* Throw away the SIGTRAP. */ | |
2779 | lp->status = 0; | |
d6b0e80f AC |
2780 | |
2781 | return 0; | |
2782 | } | |
2783 | ||
2784 | /* Select one LWP out of those that have events pending. */ | |
2785 | ||
2786 | static void | |
d90e17a7 | 2787 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2788 | { |
2789 | int num_events = 0; | |
2790 | int random_selector; | |
2791 | struct lwp_info *event_lp; | |
2792 | ||
ac264b3b | 2793 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2794 | (*orig_lp)->status = *status; |
2795 | ||
2796 | /* Give preference to any LWP that is being single-stepped. */ | |
d90e17a7 PA |
2797 | event_lp = iterate_over_lwps (filter, |
2798 | select_singlestep_lwp_callback, NULL); | |
d6b0e80f AC |
2799 | if (event_lp != NULL) |
2800 | { | |
2801 | if (debug_linux_nat) | |
2802 | fprintf_unfiltered (gdb_stdlog, | |
2803 | "SEL: Select single-step %s\n", | |
2804 | target_pid_to_str (event_lp->ptid)); | |
2805 | } | |
2806 | else | |
2807 | { | |
2808 | /* No single-stepping LWP. Select one at random, out of those | |
2809 | which have had SIGTRAP events. */ | |
2810 | ||
2811 | /* First see how many SIGTRAP events we have. */ | |
d90e17a7 | 2812 | iterate_over_lwps (filter, count_events_callback, &num_events); |
d6b0e80f AC |
2813 | |
2814 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2815 | random_selector = (int) | |
2816 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2817 | ||
2818 | if (debug_linux_nat && num_events > 1) | |
2819 | fprintf_unfiltered (gdb_stdlog, | |
2820 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2821 | num_events, random_selector); | |
2822 | ||
d90e17a7 PA |
2823 | event_lp = iterate_over_lwps (filter, |
2824 | select_event_lwp_callback, | |
d6b0e80f AC |
2825 | &random_selector); |
2826 | } | |
2827 | ||
2828 | if (event_lp != NULL) | |
2829 | { | |
2830 | /* Switch the event LWP. */ | |
2831 | *orig_lp = event_lp; | |
2832 | *status = event_lp->status; | |
2833 | } | |
2834 | ||
2835 | /* Flush the wait status for the event LWP. */ | |
2836 | (*orig_lp)->status = 0; | |
2837 | } | |
2838 | ||
2839 | /* Return non-zero if LP has been resumed. */ | |
2840 | ||
2841 | static int | |
2842 | resumed_callback (struct lwp_info *lp, void *data) | |
2843 | { | |
2844 | return lp->resumed; | |
2845 | } | |
2846 | ||
12d9289a PA |
2847 | /* Stop an active thread, verify it still exists, then resume it. If |
2848 | the thread ends up with a pending status, then it is not resumed, | |
2849 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2850 | |
2851 | static int | |
2852 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2853 | { | |
12d9289a PA |
2854 | int *new_pending_p = data; |
2855 | ||
25289eb2 | 2856 | if (!lp->stopped) |
d6b0e80f | 2857 | { |
25289eb2 PA |
2858 | ptid_t ptid = lp->ptid; |
2859 | ||
d6b0e80f AC |
2860 | stop_callback (lp, NULL); |
2861 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2862 | |
2863 | /* Resume if the lwp still exists, and the core wanted it | |
2864 | running. */ | |
12d9289a PA |
2865 | lp = find_lwp_pid (ptid); |
2866 | if (lp != NULL) | |
25289eb2 | 2867 | { |
12d9289a PA |
2868 | if (lp->last_resume_kind == resume_stop |
2869 | && lp->status == 0) | |
2870 | { | |
2871 | /* The core wanted the LWP to stop. Even if it stopped | |
2872 | cleanly (with SIGSTOP), leave the event pending. */ | |
2873 | if (debug_linux_nat) | |
2874 | fprintf_unfiltered (gdb_stdlog, | |
2875 | "SARC: core wanted LWP %ld stopped " | |
2876 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2877 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2878 | lp->status = W_STOPCODE (SIGSTOP); |
2879 | } | |
2880 | ||
2881 | if (lp->status == 0) | |
2882 | { | |
2883 | if (debug_linux_nat) | |
2884 | fprintf_unfiltered (gdb_stdlog, | |
2885 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2886 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2887 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2888 | } |
2889 | else | |
2890 | { | |
2891 | if (debug_linux_nat) | |
2892 | fprintf_unfiltered (gdb_stdlog, | |
2893 | "SARC: not re-resuming LWP %ld " | |
2894 | "(has pending)\n", | |
dfd4cc63 | 2895 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2896 | if (new_pending_p) |
2897 | *new_pending_p = 1; | |
2898 | } | |
25289eb2 | 2899 | } |
d6b0e80f AC |
2900 | } |
2901 | return 0; | |
2902 | } | |
2903 | ||
02f3fc28 | 2904 | /* Check if we should go on and pass this event to common code. |
12d9289a PA |
2905 | Return the affected lwp if we are, or NULL otherwise. If we stop |
2906 | all lwps temporarily, we may end up with new pending events in some | |
2907 | other lwp. In that case set *NEW_PENDING_P to true. */ | |
2908 | ||
02f3fc28 | 2909 | static struct lwp_info * |
0e5bf2a8 | 2910 | linux_nat_filter_event (int lwpid, int status, int *new_pending_p) |
02f3fc28 PA |
2911 | { |
2912 | struct lwp_info *lp; | |
2913 | ||
12d9289a PA |
2914 | *new_pending_p = 0; |
2915 | ||
02f3fc28 PA |
2916 | lp = find_lwp_pid (pid_to_ptid (lwpid)); |
2917 | ||
2918 | /* Check for stop events reported by a process we didn't already | |
2919 | know about - anything not already in our LWP list. | |
2920 | ||
2921 | If we're expecting to receive stopped processes after | |
2922 | fork, vfork, and clone events, then we'll just add the | |
2923 | new one to our list and go back to waiting for the event | |
2924 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2925 | from waitpid before or after the event is. |
2926 | ||
2927 | But note the case of a non-leader thread exec'ing after the | |
2928 | leader having exited, and gone from our lists. The non-leader | |
2929 | thread changes its tid to the tgid. */ | |
2930 | ||
2931 | if (WIFSTOPPED (status) && lp == NULL | |
2932 | && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC)) | |
2933 | { | |
2934 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2935 | if (debug_linux_nat) | |
2936 | fprintf_unfiltered (gdb_stdlog, | |
2937 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2938 | lwpid); | |
2939 | ||
dfd4cc63 | 2940 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2941 | lp->stopped = 1; |
2942 | lp->resumed = 1; | |
2943 | add_thread (lp->ptid); | |
2944 | } | |
2945 | ||
02f3fc28 PA |
2946 | if (WIFSTOPPED (status) && !lp) |
2947 | { | |
84636d28 | 2948 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2949 | return NULL; |
2950 | } | |
2951 | ||
2952 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2953 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2954 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2955 | exits. */ |
2956 | if (!WIFSTOPPED (status) && !lp) | |
2957 | return NULL; | |
2958 | ||
ca2163eb PA |
2959 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2960 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2961 | { | |
2962 | /* No longer need the sysgood bit. The ptrace event ends up | |
2963 | recorded in lp->waitstatus if we care for it. We can carry | |
2964 | on handling the event like a regular SIGTRAP from here | |
2965 | on. */ | |
2966 | status = W_STOPCODE (SIGTRAP); | |
2967 | if (linux_handle_syscall_trap (lp, 0)) | |
2968 | return NULL; | |
2969 | } | |
02f3fc28 | 2970 | |
ca2163eb PA |
2971 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2972 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
02f3fc28 PA |
2973 | { |
2974 | if (debug_linux_nat) | |
2975 | fprintf_unfiltered (gdb_stdlog, | |
2976 | "LLW: Handling extended status 0x%06x\n", | |
2977 | status); | |
2978 | if (linux_handle_extended_wait (lp, status, 0)) | |
2979 | return NULL; | |
2980 | } | |
2981 | ||
26ab7092 | 2982 | if (linux_nat_status_is_event (status)) |
da559b09 | 2983 | save_sigtrap (lp); |
ca2163eb | 2984 | |
02f3fc28 | 2985 | /* Check if the thread has exited. */ |
d90e17a7 | 2986 | if ((WIFEXITED (status) || WIFSIGNALED (status)) |
dfd4cc63 | 2987 | && num_lwps (ptid_get_pid (lp->ptid)) > 1) |
02f3fc28 | 2988 | { |
9db03742 JB |
2989 | /* If this is the main thread, we must stop all threads and verify |
2990 | if they are still alive. This is because in the nptl thread model | |
2991 | on Linux 2.4, there is no signal issued for exiting LWPs | |
02f3fc28 PA |
2992 | other than the main thread. We only get the main thread exit |
2993 | signal once all child threads have already exited. If we | |
2994 | stop all the threads and use the stop_wait_callback to check | |
2995 | if they have exited we can determine whether this signal | |
2996 | should be ignored or whether it means the end of the debugged | |
2997 | application, regardless of which threading model is being | |
5d3b6af6 | 2998 | used. */ |
dfd4cc63 | 2999 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
02f3fc28 PA |
3000 | { |
3001 | lp->stopped = 1; | |
dfd4cc63 | 3002 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), |
12d9289a | 3003 | stop_and_resume_callback, new_pending_p); |
02f3fc28 PA |
3004 | } |
3005 | ||
3006 | if (debug_linux_nat) | |
3007 | fprintf_unfiltered (gdb_stdlog, | |
3008 | "LLW: %s exited.\n", | |
3009 | target_pid_to_str (lp->ptid)); | |
3010 | ||
dfd4cc63 | 3011 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) |
9db03742 JB |
3012 | { |
3013 | /* If there is at least one more LWP, then the exit signal | |
3014 | was not the end of the debugged application and should be | |
3015 | ignored. */ | |
3016 | exit_lwp (lp); | |
3017 | return NULL; | |
3018 | } | |
02f3fc28 PA |
3019 | } |
3020 | ||
3021 | /* Check if the current LWP has previously exited. In the nptl | |
3022 | thread model, LWPs other than the main thread do not issue | |
3023 | signals when they exit so we must check whenever the thread has | |
3024 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3025 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3026 | { |
dfd4cc63 | 3027 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3028 | |
02f3fc28 PA |
3029 | if (debug_linux_nat) |
3030 | fprintf_unfiltered (gdb_stdlog, | |
3031 | "LLW: %s exited.\n", | |
3032 | target_pid_to_str (lp->ptid)); | |
3033 | ||
3034 | exit_lwp (lp); | |
3035 | ||
3036 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3037 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3038 | |
3039 | /* Discard the event. */ | |
3040 | return NULL; | |
3041 | } | |
3042 | ||
3043 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3044 | an attempt to stop an LWP. */ | |
3045 | if (lp->signalled | |
3046 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3047 | { | |
3048 | if (debug_linux_nat) | |
3049 | fprintf_unfiltered (gdb_stdlog, | |
3050 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3051 | target_pid_to_str (lp->ptid)); | |
3052 | ||
02f3fc28 PA |
3053 | lp->signalled = 0; |
3054 | ||
25289eb2 PA |
3055 | if (lp->last_resume_kind != resume_stop) |
3056 | { | |
3057 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3058 | |
25289eb2 PA |
3059 | registers_changed (); |
3060 | ||
7b50312a PA |
3061 | if (linux_nat_prepare_to_resume != NULL) |
3062 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3063 | linux_ops->to_resume (linux_ops, |
3064 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
3065 | lp->step, GDB_SIGNAL_0); | |
25289eb2 PA |
3066 | if (debug_linux_nat) |
3067 | fprintf_unfiltered (gdb_stdlog, | |
3068 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3069 | lp->step ? | |
3070 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3071 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3072 | |
25289eb2 PA |
3073 | lp->stopped = 0; |
3074 | gdb_assert (lp->resumed); | |
02f3fc28 | 3075 | |
25289eb2 PA |
3076 | /* Discard the event. */ |
3077 | return NULL; | |
3078 | } | |
02f3fc28 PA |
3079 | } |
3080 | ||
57380f4e DJ |
3081 | /* Make sure we don't report a SIGINT that we have already displayed |
3082 | for another thread. */ | |
3083 | if (lp->ignore_sigint | |
3084 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3085 | { | |
3086 | if (debug_linux_nat) | |
3087 | fprintf_unfiltered (gdb_stdlog, | |
3088 | "LLW: Delayed SIGINT caught for %s.\n", | |
3089 | target_pid_to_str (lp->ptid)); | |
3090 | ||
3091 | /* This is a delayed SIGINT. */ | |
3092 | lp->ignore_sigint = 0; | |
3093 | ||
3094 | registers_changed (); | |
7b50312a PA |
3095 | if (linux_nat_prepare_to_resume != NULL) |
3096 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3097 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3098 | lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3099 | if (debug_linux_nat) |
3100 | fprintf_unfiltered (gdb_stdlog, | |
3101 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3102 | lp->step ? | |
3103 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3104 | target_pid_to_str (lp->ptid)); | |
3105 | ||
3106 | lp->stopped = 0; | |
3107 | gdb_assert (lp->resumed); | |
3108 | ||
3109 | /* Discard the event. */ | |
3110 | return NULL; | |
3111 | } | |
3112 | ||
02f3fc28 PA |
3113 | /* An interesting event. */ |
3114 | gdb_assert (lp); | |
ca2163eb | 3115 | lp->status = status; |
02f3fc28 PA |
3116 | return lp; |
3117 | } | |
3118 | ||
0e5bf2a8 PA |
3119 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3120 | their exits until all other threads in the group have exited. */ | |
3121 | ||
3122 | static void | |
3123 | check_zombie_leaders (void) | |
3124 | { | |
3125 | struct inferior *inf; | |
3126 | ||
3127 | ALL_INFERIORS (inf) | |
3128 | { | |
3129 | struct lwp_info *leader_lp; | |
3130 | ||
3131 | if (inf->pid == 0) | |
3132 | continue; | |
3133 | ||
3134 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3135 | if (leader_lp != NULL | |
3136 | /* Check if there are other threads in the group, as we may | |
3137 | have raced with the inferior simply exiting. */ | |
3138 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3139 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3140 | { |
3141 | if (debug_linux_nat) | |
3142 | fprintf_unfiltered (gdb_stdlog, | |
3143 | "CZL: Thread group leader %d zombie " | |
3144 | "(it exited, or another thread execd).\n", | |
3145 | inf->pid); | |
3146 | ||
3147 | /* A leader zombie can mean one of two things: | |
3148 | ||
3149 | - It exited, and there's an exit status pending | |
3150 | available, or only the leader exited (not the whole | |
3151 | program). In the latter case, we can't waitpid the | |
3152 | leader's exit status until all other threads are gone. | |
3153 | ||
3154 | - There are 3 or more threads in the group, and a thread | |
3155 | other than the leader exec'd. On an exec, the Linux | |
3156 | kernel destroys all other threads (except the execing | |
3157 | one) in the thread group, and resets the execing thread's | |
3158 | tid to the tgid. No exit notification is sent for the | |
3159 | execing thread -- from the ptracer's perspective, it | |
3160 | appears as though the execing thread just vanishes. | |
3161 | Until we reap all other threads except the leader and the | |
3162 | execing thread, the leader will be zombie, and the | |
3163 | execing thread will be in `D (disc sleep)'. As soon as | |
3164 | all other threads are reaped, the execing thread changes | |
3165 | it's tid to the tgid, and the previous (zombie) leader | |
3166 | vanishes, giving place to the "new" leader. We could try | |
3167 | distinguishing the exit and exec cases, by waiting once | |
3168 | more, and seeing if something comes out, but it doesn't | |
3169 | sound useful. The previous leader _does_ go away, and | |
3170 | we'll re-add the new one once we see the exec event | |
3171 | (which is just the same as what would happen if the | |
3172 | previous leader did exit voluntarily before some other | |
3173 | thread execs). */ | |
3174 | ||
3175 | if (debug_linux_nat) | |
3176 | fprintf_unfiltered (gdb_stdlog, | |
3177 | "CZL: Thread group leader %d vanished.\n", | |
3178 | inf->pid); | |
3179 | exit_lwp (leader_lp); | |
3180 | } | |
3181 | } | |
3182 | } | |
3183 | ||
d6b0e80f | 3184 | static ptid_t |
7feb7d06 | 3185 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3186 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3187 | int target_options) | |
d6b0e80f | 3188 | { |
7feb7d06 | 3189 | static sigset_t prev_mask; |
4b60df3d | 3190 | enum resume_kind last_resume_kind; |
12d9289a | 3191 | struct lwp_info *lp; |
12d9289a | 3192 | int status; |
d6b0e80f | 3193 | |
01124a23 | 3194 | if (debug_linux_nat) |
b84876c2 PA |
3195 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3196 | ||
f973ed9c DJ |
3197 | /* The first time we get here after starting a new inferior, we may |
3198 | not have added it to the LWP list yet - this is the earliest | |
3199 | moment at which we know its PID. */ | |
d90e17a7 | 3200 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3201 | { |
27c9d204 PA |
3202 | /* Upgrade the main thread's ptid. */ |
3203 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3204 | ptid_build (ptid_get_pid (inferior_ptid), |
3205 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3206 | |
26cb8b7c | 3207 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3208 | lp->resumed = 1; |
3209 | } | |
3210 | ||
12696c10 | 3211 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3212 | block_child_signals (&prev_mask); |
d6b0e80f AC |
3213 | |
3214 | retry: | |
d90e17a7 PA |
3215 | lp = NULL; |
3216 | status = 0; | |
d6b0e80f AC |
3217 | |
3218 | /* First check if there is a LWP with a wait status pending. */ | |
0e5bf2a8 | 3219 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d6b0e80f | 3220 | { |
0e5bf2a8 | 3221 | /* Any LWP in the PTID group that's been resumed will do. */ |
d90e17a7 | 3222 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
d6b0e80f AC |
3223 | if (lp) |
3224 | { | |
ca2163eb | 3225 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3226 | fprintf_unfiltered (gdb_stdlog, |
3227 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3228 | status_to_str (lp->status), |
d6b0e80f AC |
3229 | target_pid_to_str (lp->ptid)); |
3230 | } | |
d6b0e80f | 3231 | } |
dfd4cc63 | 3232 | else if (ptid_lwp_p (ptid)) |
d6b0e80f AC |
3233 | { |
3234 | if (debug_linux_nat) | |
3235 | fprintf_unfiltered (gdb_stdlog, | |
3236 | "LLW: Waiting for specific LWP %s.\n", | |
3237 | target_pid_to_str (ptid)); | |
3238 | ||
3239 | /* We have a specific LWP to check. */ | |
3240 | lp = find_lwp_pid (ptid); | |
3241 | gdb_assert (lp); | |
d6b0e80f | 3242 | |
ca2163eb | 3243 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3244 | fprintf_unfiltered (gdb_stdlog, |
3245 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3246 | status_to_str (lp->status), |
d6b0e80f AC |
3247 | target_pid_to_str (lp->ptid)); |
3248 | ||
d90e17a7 PA |
3249 | /* We check for lp->waitstatus in addition to lp->status, |
3250 | because we can have pending process exits recorded in | |
3251 | lp->status and W_EXITCODE(0,0) == 0. We should probably have | |
3252 | an additional lp->status_p flag. */ | |
ca2163eb | 3253 | if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) |
d90e17a7 | 3254 | lp = NULL; |
d6b0e80f AC |
3255 | } |
3256 | ||
b84876c2 PA |
3257 | if (!target_can_async_p ()) |
3258 | { | |
3259 | /* Causes SIGINT to be passed on to the attached process. */ | |
3260 | set_sigint_trap (); | |
b84876c2 | 3261 | } |
d6b0e80f | 3262 | |
0e5bf2a8 | 3263 | /* But if we don't find a pending event, we'll have to wait. */ |
7feb7d06 | 3264 | |
d90e17a7 | 3265 | while (lp == NULL) |
d6b0e80f AC |
3266 | { |
3267 | pid_t lwpid; | |
3268 | ||
0e5bf2a8 PA |
3269 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3270 | quirks: | |
3271 | ||
3272 | - If the thread group leader exits while other threads in the | |
3273 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3274 | waitpid won't return an exit status until the other threads | |
3275 | in the group are reapped. | |
3276 | ||
3277 | - When a non-leader thread execs, that thread just vanishes | |
3278 | without reporting an exit (so we'd hang if we waited for it | |
3279 | explicitly in that case). The exec event is reported to | |
3280 | the TGID pid. */ | |
3281 | ||
3282 | errno = 0; | |
3283 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3284 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3285 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3286 | ||
3287 | if (debug_linux_nat) | |
3288 | fprintf_unfiltered (gdb_stdlog, | |
3289 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3290 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3291 | |
d6b0e80f AC |
3292 | if (lwpid > 0) |
3293 | { | |
12d9289a PA |
3294 | /* If this is true, then we paused LWPs momentarily, and may |
3295 | now have pending events to handle. */ | |
3296 | int new_pending; | |
3297 | ||
d6b0e80f AC |
3298 | if (debug_linux_nat) |
3299 | { | |
3300 | fprintf_unfiltered (gdb_stdlog, | |
3301 | "LLW: waitpid %ld received %s\n", | |
3302 | (long) lwpid, status_to_str (status)); | |
3303 | } | |
3304 | ||
0e5bf2a8 | 3305 | lp = linux_nat_filter_event (lwpid, status, &new_pending); |
d90e17a7 | 3306 | |
33355866 JK |
3307 | /* STATUS is now no longer valid, use LP->STATUS instead. */ |
3308 | status = 0; | |
3309 | ||
0e5bf2a8 | 3310 | if (lp && !ptid_match (lp->ptid, ptid)) |
d6b0e80f | 3311 | { |
e3e9f5a2 PA |
3312 | gdb_assert (lp->resumed); |
3313 | ||
d90e17a7 | 3314 | if (debug_linux_nat) |
3e43a32a MS |
3315 | fprintf (stderr, |
3316 | "LWP %ld got an event %06x, leaving pending.\n", | |
33355866 | 3317 | ptid_get_lwp (lp->ptid), lp->status); |
d90e17a7 | 3318 | |
ca2163eb | 3319 | if (WIFSTOPPED (lp->status)) |
d90e17a7 | 3320 | { |
ca2163eb | 3321 | if (WSTOPSIG (lp->status) != SIGSTOP) |
d90e17a7 | 3322 | { |
e3e9f5a2 PA |
3323 | /* Cancel breakpoint hits. The breakpoint may |
3324 | be removed before we fetch events from this | |
3325 | process to report to the core. It is best | |
3326 | not to assume the moribund breakpoints | |
3327 | heuristic always handles these cases --- it | |
3328 | could be too many events go through to the | |
3329 | core before this one is handled. All-stop | |
3330 | always cancels breakpoint hits in all | |
3331 | threads. */ | |
3332 | if (non_stop | |
00390b84 | 3333 | && linux_nat_lp_status_is_event (lp) |
e3e9f5a2 PA |
3334 | && cancel_breakpoint (lp)) |
3335 | { | |
3336 | /* Throw away the SIGTRAP. */ | |
3337 | lp->status = 0; | |
3338 | ||
3339 | if (debug_linux_nat) | |
3340 | fprintf (stderr, | |
3e43a32a MS |
3341 | "LLW: LWP %ld hit a breakpoint while" |
3342 | " waiting for another process;" | |
3343 | " cancelled it\n", | |
e3e9f5a2 PA |
3344 | ptid_get_lwp (lp->ptid)); |
3345 | } | |
3346 | lp->stopped = 1; | |
d90e17a7 PA |
3347 | } |
3348 | else | |
3349 | { | |
3350 | lp->stopped = 1; | |
3351 | lp->signalled = 0; | |
3352 | } | |
3353 | } | |
33355866 | 3354 | else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status)) |
d90e17a7 PA |
3355 | { |
3356 | if (debug_linux_nat) | |
3e43a32a MS |
3357 | fprintf (stderr, |
3358 | "Process %ld exited while stopping LWPs\n", | |
d90e17a7 PA |
3359 | ptid_get_lwp (lp->ptid)); |
3360 | ||
3361 | /* This was the last lwp in the process. Since | |
3362 | events are serialized to GDB core, and we can't | |
3363 | report this one right now, but GDB core and the | |
3364 | other target layers will want to be notified | |
3365 | about the exit code/signal, leave the status | |
3366 | pending for the next time we're able to report | |
3367 | it. */ | |
d90e17a7 PA |
3368 | |
3369 | /* Prevent trying to stop this thread again. We'll | |
3370 | never try to resume it because it has a pending | |
3371 | status. */ | |
3372 | lp->stopped = 1; | |
3373 | ||
3374 | /* Dead LWP's aren't expected to reported a pending | |
3375 | sigstop. */ | |
3376 | lp->signalled = 0; | |
3377 | ||
3378 | /* Store the pending event in the waitstatus as | |
3379 | well, because W_EXITCODE(0,0) == 0. */ | |
ca2163eb | 3380 | store_waitstatus (&lp->waitstatus, lp->status); |
d90e17a7 PA |
3381 | } |
3382 | ||
3383 | /* Keep looking. */ | |
3384 | lp = NULL; | |
d6b0e80f AC |
3385 | } |
3386 | ||
0e5bf2a8 | 3387 | if (new_pending) |
d90e17a7 | 3388 | { |
0e5bf2a8 PA |
3389 | /* Some LWP now has a pending event. Go all the way |
3390 | back to check it. */ | |
3391 | goto retry; | |
3392 | } | |
12d9289a | 3393 | |
0e5bf2a8 PA |
3394 | if (lp) |
3395 | { | |
3396 | /* We got an event to report to the core. */ | |
3397 | break; | |
d90e17a7 | 3398 | } |
0e5bf2a8 PA |
3399 | |
3400 | /* Retry until nothing comes out of waitpid. A single | |
3401 | SIGCHLD can indicate more than one child stopped. */ | |
3402 | continue; | |
d6b0e80f AC |
3403 | } |
3404 | ||
0e5bf2a8 PA |
3405 | /* Check for zombie thread group leaders. Those can't be reaped |
3406 | until all other threads in the thread group are. */ | |
3407 | check_zombie_leaders (); | |
d6b0e80f | 3408 | |
0e5bf2a8 PA |
3409 | /* If there are no resumed children left, bail. We'd be stuck |
3410 | forever in the sigsuspend call below otherwise. */ | |
3411 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3412 | { | |
3413 | if (debug_linux_nat) | |
3414 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3415 | |
0e5bf2a8 | 3416 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3417 | |
0e5bf2a8 PA |
3418 | if (!target_can_async_p ()) |
3419 | clear_sigint_trap (); | |
b84876c2 | 3420 | |
0e5bf2a8 PA |
3421 | restore_child_signals_mask (&prev_mask); |
3422 | return minus_one_ptid; | |
d6b0e80f | 3423 | } |
28736962 | 3424 | |
0e5bf2a8 PA |
3425 | /* No interesting event to report to the core. */ |
3426 | ||
3427 | if (target_options & TARGET_WNOHANG) | |
3428 | { | |
01124a23 | 3429 | if (debug_linux_nat) |
28736962 PA |
3430 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3431 | ||
0e5bf2a8 | 3432 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3433 | restore_child_signals_mask (&prev_mask); |
3434 | return minus_one_ptid; | |
3435 | } | |
d6b0e80f AC |
3436 | |
3437 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3438 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3439 | |
3440 | /* Block until we get an event reported with SIGCHLD. */ | |
3441 | sigsuspend (&suspend_mask); | |
d6b0e80f AC |
3442 | } |
3443 | ||
b84876c2 | 3444 | if (!target_can_async_p ()) |
d26b5354 | 3445 | clear_sigint_trap (); |
d6b0e80f AC |
3446 | |
3447 | gdb_assert (lp); | |
3448 | ||
ca2163eb PA |
3449 | status = lp->status; |
3450 | lp->status = 0; | |
3451 | ||
d6b0e80f AC |
3452 | /* Don't report signals that GDB isn't interested in, such as |
3453 | signals that are neither printed nor stopped upon. Stopping all | |
3454 | threads can be a bit time-consuming so if we want decent | |
3455 | performance with heavily multi-threaded programs, especially when | |
3456 | they're using a high frequency timer, we'd better avoid it if we | |
3457 | can. */ | |
3458 | ||
3459 | if (WIFSTOPPED (status)) | |
3460 | { | |
2ea28649 | 3461 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); |
d6b0e80f | 3462 | |
2455069d UW |
3463 | /* When using hardware single-step, we need to report every signal. |
3464 | Otherwise, signals in pass_mask may be short-circuited. */ | |
d539ed7e | 3465 | if (!lp->step |
2455069d | 3466 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))) |
d6b0e80f AC |
3467 | { |
3468 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
3469 | here? It is not clear we should. GDB may not expect | |
3470 | other threads to run. On the other hand, not resuming | |
3471 | newly attached threads may cause an unwanted delay in | |
3472 | getting them running. */ | |
3473 | registers_changed (); | |
7b50312a PA |
3474 | if (linux_nat_prepare_to_resume != NULL) |
3475 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3476 | linux_ops->to_resume (linux_ops, |
3477 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
10d6c8cd | 3478 | lp->step, signo); |
d6b0e80f AC |
3479 | if (debug_linux_nat) |
3480 | fprintf_unfiltered (gdb_stdlog, | |
3481 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3482 | lp->step ? | |
3483 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3484 | target_pid_to_str (lp->ptid), | |
a493e3e2 | 3485 | (signo != GDB_SIGNAL_0 |
2ea28649 | 3486 | ? strsignal (gdb_signal_to_host (signo)) |
423ec54c | 3487 | : "0")); |
d6b0e80f | 3488 | lp->stopped = 0; |
d6b0e80f AC |
3489 | goto retry; |
3490 | } | |
3491 | ||
1ad15515 | 3492 | if (!non_stop) |
d6b0e80f | 3493 | { |
1ad15515 PA |
3494 | /* Only do the below in all-stop, as we currently use SIGINT |
3495 | to implement target_stop (see linux_nat_stop) in | |
3496 | non-stop. */ | |
a493e3e2 | 3497 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) |
1ad15515 PA |
3498 | { |
3499 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3500 | forwarded to the entire process group, that is, all LWPs | |
3501 | will receive it - unless they're using CLONE_THREAD to | |
3502 | share signals. Since we only want to report it once, we | |
3503 | mark it as ignored for all LWPs except this one. */ | |
d90e17a7 PA |
3504 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)), |
3505 | set_ignore_sigint, NULL); | |
1ad15515 PA |
3506 | lp->ignore_sigint = 0; |
3507 | } | |
3508 | else | |
3509 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
3510 | } |
3511 | } | |
3512 | ||
3513 | /* This LWP is stopped now. */ | |
3514 | lp->stopped = 1; | |
3515 | ||
3516 | if (debug_linux_nat) | |
3517 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
3518 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
3519 | ||
4c28f408 PA |
3520 | if (!non_stop) |
3521 | { | |
3522 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3523 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3524 | |
3525 | /* ... and wait until all of them have reported back that | |
3526 | they're no longer running. */ | |
d90e17a7 | 3527 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
4c28f408 PA |
3528 | |
3529 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3530 | from among those that have had events. Giving equal priority | |
3531 | to all LWPs that have had events helps prevent | |
3532 | starvation. */ | |
0e5bf2a8 | 3533 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d90e17a7 | 3534 | select_event_lwp (ptid, &lp, &status); |
d6b0e80f | 3535 | |
e3e9f5a2 PA |
3536 | /* Now that we've selected our final event LWP, cancel any |
3537 | breakpoints in other LWPs that have hit a GDB breakpoint. | |
3538 | See the comment in cancel_breakpoints_callback to find out | |
3539 | why. */ | |
3540 | iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp); | |
3541 | ||
4b60df3d PA |
3542 | /* We'll need this to determine whether to report a SIGSTOP as |
3543 | TARGET_WAITKIND_0. Need to take a copy because | |
3544 | resume_clear_callback clears it. */ | |
3545 | last_resume_kind = lp->last_resume_kind; | |
3546 | ||
e3e9f5a2 PA |
3547 | /* In all-stop, from the core's perspective, all LWPs are now |
3548 | stopped until a new resume action is sent over. */ | |
3549 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3550 | } | |
3551 | else | |
25289eb2 | 3552 | { |
4b60df3d PA |
3553 | /* See above. */ |
3554 | last_resume_kind = lp->last_resume_kind; | |
3555 | resume_clear_callback (lp, NULL); | |
25289eb2 | 3556 | } |
d6b0e80f | 3557 | |
26ab7092 | 3558 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3559 | { |
d6b0e80f AC |
3560 | if (debug_linux_nat) |
3561 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3562 | "LLW: trap ptid is %s.\n", |
3563 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3564 | } |
d6b0e80f AC |
3565 | |
3566 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3567 | { | |
3568 | *ourstatus = lp->waitstatus; | |
3569 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3570 | } | |
3571 | else | |
3572 | store_waitstatus (ourstatus, status); | |
3573 | ||
01124a23 | 3574 | if (debug_linux_nat) |
b84876c2 PA |
3575 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3576 | ||
7feb7d06 | 3577 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3578 | |
4b60df3d | 3579 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3580 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3581 | && WSTOPSIG (status) == SIGSTOP) | |
3582 | { | |
3583 | /* A thread that has been requested to stop by GDB with | |
3584 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3585 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3586 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3587 | } |
3588 | ||
1e225492 JK |
3589 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3590 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3591 | lp->core = -1; | |
3592 | else | |
2e794194 | 3593 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3594 | |
f973ed9c | 3595 | return lp->ptid; |
d6b0e80f AC |
3596 | } |
3597 | ||
e3e9f5a2 PA |
3598 | /* Resume LWPs that are currently stopped without any pending status |
3599 | to report, but are resumed from the core's perspective. */ | |
3600 | ||
3601 | static int | |
3602 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3603 | { | |
3604 | ptid_t *wait_ptid_p = data; | |
3605 | ||
3606 | if (lp->stopped | |
3607 | && lp->resumed | |
3608 | && lp->status == 0 | |
3609 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
3610 | { | |
336060f3 PA |
3611 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3612 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
3613 | CORE_ADDR pc = regcache_read_pc (regcache); | |
3614 | ||
e3e9f5a2 PA |
3615 | gdb_assert (is_executing (lp->ptid)); |
3616 | ||
3617 | /* Don't bother if there's a breakpoint at PC that we'd hit | |
3618 | immediately, and we're not waiting for this LWP. */ | |
3619 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3620 | { | |
e3e9f5a2 PA |
3621 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
3622 | return 0; | |
3623 | } | |
3624 | ||
3625 | if (debug_linux_nat) | |
3626 | fprintf_unfiltered (gdb_stdlog, | |
336060f3 PA |
3627 | "RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", |
3628 | target_pid_to_str (lp->ptid), | |
3629 | paddress (gdbarch, pc), | |
3630 | lp->step); | |
e3e9f5a2 | 3631 | |
336060f3 | 3632 | registers_changed (); |
7b50312a PA |
3633 | if (linux_nat_prepare_to_resume != NULL) |
3634 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3635 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3636 | lp->step, GDB_SIGNAL_0); |
e3e9f5a2 | 3637 | lp->stopped = 0; |
e3e9f5a2 PA |
3638 | lp->stopped_by_watchpoint = 0; |
3639 | } | |
3640 | ||
3641 | return 0; | |
3642 | } | |
3643 | ||
7feb7d06 PA |
3644 | static ptid_t |
3645 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3646 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3647 | int target_options) | |
7feb7d06 PA |
3648 | { |
3649 | ptid_t event_ptid; | |
3650 | ||
3651 | if (debug_linux_nat) | |
09826ec5 PA |
3652 | { |
3653 | char *options_string; | |
3654 | ||
3655 | options_string = target_options_to_string (target_options); | |
3656 | fprintf_unfiltered (gdb_stdlog, | |
3657 | "linux_nat_wait: [%s], [%s]\n", | |
3658 | target_pid_to_str (ptid), | |
3659 | options_string); | |
3660 | xfree (options_string); | |
3661 | } | |
7feb7d06 PA |
3662 | |
3663 | /* Flush the async file first. */ | |
3664 | if (target_can_async_p ()) | |
3665 | async_file_flush (); | |
3666 | ||
e3e9f5a2 PA |
3667 | /* Resume LWPs that are currently stopped without any pending status |
3668 | to report, but are resumed from the core's perspective. LWPs get | |
3669 | in this state if we find them stopping at a time we're not | |
3670 | interested in reporting the event (target_wait on a | |
3671 | specific_process, for example, see linux_nat_wait_1), and | |
3672 | meanwhile the event became uninteresting. Don't bother resuming | |
3673 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3674 | if (non_stop) | |
3675 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3676 | ||
47608cb1 | 3677 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3678 | |
3679 | /* If we requested any event, and something came out, assume there | |
3680 | may be more. If we requested a specific lwp or process, also | |
3681 | assume there may be more. */ | |
3682 | if (target_can_async_p () | |
6953d224 PA |
3683 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3684 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3685 | || !ptid_equal (ptid, minus_one_ptid))) |
3686 | async_file_mark (); | |
3687 | ||
3688 | /* Get ready for the next event. */ | |
3689 | if (target_can_async_p ()) | |
3690 | target_async (inferior_event_handler, 0); | |
3691 | ||
3692 | return event_ptid; | |
3693 | } | |
3694 | ||
d6b0e80f AC |
3695 | static int |
3696 | kill_callback (struct lwp_info *lp, void *data) | |
3697 | { | |
ed731959 JK |
3698 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3699 | ||
3700 | errno = 0; | |
dfd4cc63 | 3701 | kill (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 JK |
3702 | if (debug_linux_nat) |
3703 | fprintf_unfiltered (gdb_stdlog, | |
3704 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3705 | target_pid_to_str (lp->ptid), | |
3706 | errno ? safe_strerror (errno) : "OK"); | |
3707 | ||
3708 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3709 | ||
d6b0e80f | 3710 | errno = 0; |
dfd4cc63 | 3711 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f AC |
3712 | if (debug_linux_nat) |
3713 | fprintf_unfiltered (gdb_stdlog, | |
3714 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3715 | target_pid_to_str (lp->ptid), | |
3716 | errno ? safe_strerror (errno) : "OK"); | |
3717 | ||
3718 | return 0; | |
3719 | } | |
3720 | ||
3721 | static int | |
3722 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3723 | { | |
3724 | pid_t pid; | |
3725 | ||
3726 | /* We must make sure that there are no pending events (delayed | |
3727 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3728 | program doesn't interfere with any following debugging session. */ | |
3729 | ||
3730 | /* For cloned processes we must check both with __WCLONE and | |
3731 | without, since the exit status of a cloned process isn't reported | |
3732 | with __WCLONE. */ | |
3733 | if (lp->cloned) | |
3734 | { | |
3735 | do | |
3736 | { | |
dfd4cc63 | 3737 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3738 | if (pid != (pid_t) -1) |
d6b0e80f | 3739 | { |
e85a822c DJ |
3740 | if (debug_linux_nat) |
3741 | fprintf_unfiltered (gdb_stdlog, | |
3742 | "KWC: wait %s received unknown.\n", | |
3743 | target_pid_to_str (lp->ptid)); | |
3744 | /* The Linux kernel sometimes fails to kill a thread | |
3745 | completely after PTRACE_KILL; that goes from the stop | |
3746 | point in do_fork out to the one in | |
3747 | get_signal_to_deliever and waits again. So kill it | |
3748 | again. */ | |
3749 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3750 | } |
3751 | } | |
dfd4cc63 | 3752 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3753 | |
3754 | gdb_assert (pid == -1 && errno == ECHILD); | |
3755 | } | |
3756 | ||
3757 | do | |
3758 | { | |
dfd4cc63 | 3759 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3760 | if (pid != (pid_t) -1) |
d6b0e80f | 3761 | { |
e85a822c DJ |
3762 | if (debug_linux_nat) |
3763 | fprintf_unfiltered (gdb_stdlog, | |
3764 | "KWC: wait %s received unk.\n", | |
3765 | target_pid_to_str (lp->ptid)); | |
3766 | /* See the call to kill_callback above. */ | |
3767 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3768 | } |
3769 | } | |
dfd4cc63 | 3770 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3771 | |
3772 | gdb_assert (pid == -1 && errno == ECHILD); | |
3773 | return 0; | |
3774 | } | |
3775 | ||
3776 | static void | |
7d85a9c0 | 3777 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3778 | { |
f973ed9c DJ |
3779 | struct target_waitstatus last; |
3780 | ptid_t last_ptid; | |
3781 | int status; | |
d6b0e80f | 3782 | |
f973ed9c DJ |
3783 | /* If we're stopped while forking and we haven't followed yet, |
3784 | kill the other task. We need to do this first because the | |
3785 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3786 | |
f973ed9c | 3787 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3788 | |
f973ed9c DJ |
3789 | if (last.kind == TARGET_WAITKIND_FORKED |
3790 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3791 | { | |
dfd4cc63 | 3792 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3793 | wait (&status); |
26cb8b7c PA |
3794 | |
3795 | /* Let the arch-specific native code know this process is | |
3796 | gone. */ | |
dfd4cc63 | 3797 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3798 | } |
3799 | ||
3800 | if (forks_exist_p ()) | |
7feb7d06 | 3801 | linux_fork_killall (); |
f973ed9c DJ |
3802 | else |
3803 | { | |
d90e17a7 | 3804 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3805 | |
4c28f408 PA |
3806 | /* Stop all threads before killing them, since ptrace requires |
3807 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3808 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3809 | /* ... and wait until all of them have reported back that |
3810 | they're no longer running. */ | |
d90e17a7 | 3811 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3812 | |
f973ed9c | 3813 | /* Kill all LWP's ... */ |
d90e17a7 | 3814 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3815 | |
3816 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3817 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3818 | } |
3819 | ||
3820 | target_mourn_inferior (); | |
d6b0e80f AC |
3821 | } |
3822 | ||
3823 | static void | |
136d6dae | 3824 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3825 | { |
26cb8b7c PA |
3826 | int pid = ptid_get_pid (inferior_ptid); |
3827 | ||
3828 | purge_lwp_list (pid); | |
d6b0e80f | 3829 | |
f973ed9c | 3830 | if (! forks_exist_p ()) |
d90e17a7 PA |
3831 | /* Normal case, no other forks available. */ |
3832 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3833 | else |
3834 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3835 | there are other viable forks to debug. Delete the exiting | |
3836 | one and context-switch to the first available. */ | |
3837 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3838 | |
3839 | /* Let the arch-specific native code know this process is gone. */ | |
3840 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3841 | } |
3842 | ||
5b009018 PA |
3843 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3844 | layout of the inferiors' architecture. */ | |
3845 | ||
3846 | static void | |
a5362b9a | 3847 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3848 | { |
3849 | int done = 0; | |
3850 | ||
3851 | if (linux_nat_siginfo_fixup != NULL) | |
3852 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3853 | ||
3854 | /* If there was no callback, or the callback didn't do anything, | |
3855 | then just do a straight memcpy. */ | |
3856 | if (!done) | |
3857 | { | |
3858 | if (direction == 1) | |
a5362b9a | 3859 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3860 | else |
a5362b9a | 3861 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3862 | } |
3863 | } | |
3864 | ||
9b409511 | 3865 | static enum target_xfer_status |
4aa995e1 PA |
3866 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3867 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3868 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3869 | ULONGEST *xfered_len) | |
4aa995e1 | 3870 | { |
4aa995e1 | 3871 | int pid; |
a5362b9a TS |
3872 | siginfo_t siginfo; |
3873 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3874 | |
3875 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3876 | gdb_assert (readbuf || writebuf); | |
3877 | ||
dfd4cc63 | 3878 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3879 | if (pid == 0) |
dfd4cc63 | 3880 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3881 | |
3882 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3883 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3884 | |
3885 | errno = 0; | |
3886 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3887 | if (errno != 0) | |
2ed4b548 | 3888 | return TARGET_XFER_E_IO; |
4aa995e1 | 3889 | |
5b009018 PA |
3890 | /* When GDB is built as a 64-bit application, ptrace writes into |
3891 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3892 | inferior with a 64-bit GDB should look the same as debugging it | |
3893 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3894 | the converted layout, so any read/write will have to be done | |
3895 | post-conversion. */ | |
3896 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3897 | ||
4aa995e1 PA |
3898 | if (offset + len > sizeof (siginfo)) |
3899 | len = sizeof (siginfo) - offset; | |
3900 | ||
3901 | if (readbuf != NULL) | |
5b009018 | 3902 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3903 | else |
3904 | { | |
5b009018 PA |
3905 | memcpy (inf_siginfo + offset, writebuf, len); |
3906 | ||
3907 | /* Convert back to ptrace layout before flushing it out. */ | |
3908 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3909 | ||
4aa995e1 PA |
3910 | errno = 0; |
3911 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3912 | if (errno != 0) | |
2ed4b548 | 3913 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3914 | } |
3915 | ||
9b409511 YQ |
3916 | *xfered_len = len; |
3917 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3918 | } |
3919 | ||
9b409511 | 3920 | static enum target_xfer_status |
10d6c8cd DJ |
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, | |
9b409511 | 3924 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3925 | { |
4aa995e1 | 3926 | struct cleanup *old_chain; |
9b409511 | 3927 | enum target_xfer_status xfer; |
d6b0e80f | 3928 | |
4aa995e1 PA |
3929 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3930 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3931 | offset, len, xfered_len); |
4aa995e1 | 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)) | |
9b409511 | 3937 | return TARGET_XFER_EOF; |
c35b1492 | 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 | 3944 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3945 | offset, len, xfered_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 | ||
9b409511 | 4115 | static enum target_xfer_status |
10d6c8cd DJ |
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, | |
9b409511 | 4119 | ULONGEST offset, LONGEST len, ULONGEST *xfered_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)) | |
9b409511 | 4130 | return TARGET_XFER_EOF; |
dba24537 AC |
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 | 4137 | if (fd == -1) |
9b409511 | 4138 | return TARGET_XFER_EOF; |
dba24537 AC |
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); | |
9b409511 YQ |
4154 | |
4155 | if (ret == 0) | |
4156 | return TARGET_XFER_EOF; | |
4157 | else | |
4158 | { | |
4159 | *xfered_len = ret; | |
4160 | return TARGET_XFER_OK; | |
4161 | } | |
dba24537 AC |
4162 | } |
4163 | ||
efcbbd14 UW |
4164 | |
4165 | /* Enumerate spufs IDs for process PID. */ | |
4166 | static LONGEST | |
b55e14c7 | 4167 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4168 | { |
f5656ead | 4169 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4170 | LONGEST pos = 0; |
4171 | LONGEST written = 0; | |
4172 | char path[128]; | |
4173 | DIR *dir; | |
4174 | struct dirent *entry; | |
4175 | ||
4176 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4177 | dir = opendir (path); | |
4178 | if (!dir) | |
4179 | return -1; | |
4180 | ||
4181 | rewinddir (dir); | |
4182 | while ((entry = readdir (dir)) != NULL) | |
4183 | { | |
4184 | struct stat st; | |
4185 | struct statfs stfs; | |
4186 | int fd; | |
4187 | ||
4188 | fd = atoi (entry->d_name); | |
4189 | if (!fd) | |
4190 | continue; | |
4191 | ||
4192 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4193 | if (stat (path, &st) != 0) | |
4194 | continue; | |
4195 | if (!S_ISDIR (st.st_mode)) | |
4196 | continue; | |
4197 | ||
4198 | if (statfs (path, &stfs) != 0) | |
4199 | continue; | |
4200 | if (stfs.f_type != SPUFS_MAGIC) | |
4201 | continue; | |
4202 | ||
4203 | if (pos >= offset && pos + 4 <= offset + len) | |
4204 | { | |
4205 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4206 | written += 4; | |
4207 | } | |
4208 | pos += 4; | |
4209 | } | |
4210 | ||
4211 | closedir (dir); | |
4212 | return written; | |
4213 | } | |
4214 | ||
4215 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4216 | object type, using the /proc file system. */ | |
9b409511 YQ |
4217 | |
4218 | static enum target_xfer_status | |
efcbbd14 UW |
4219 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4220 | const char *annex, gdb_byte *readbuf, | |
4221 | const gdb_byte *writebuf, | |
9b409511 | 4222 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4223 | { |
4224 | char buf[128]; | |
4225 | int fd = 0; | |
4226 | int ret = -1; | |
dfd4cc63 | 4227 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4228 | |
4229 | if (!annex) | |
4230 | { | |
4231 | if (!readbuf) | |
2ed4b548 | 4232 | return TARGET_XFER_E_IO; |
efcbbd14 | 4233 | else |
9b409511 YQ |
4234 | { |
4235 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4236 | ||
4237 | if (l < 0) | |
4238 | return TARGET_XFER_E_IO; | |
4239 | else if (l == 0) | |
4240 | return TARGET_XFER_EOF; | |
4241 | else | |
4242 | { | |
4243 | *xfered_len = (ULONGEST) l; | |
4244 | return TARGET_XFER_OK; | |
4245 | } | |
4246 | } | |
efcbbd14 UW |
4247 | } |
4248 | ||
4249 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4250 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4251 | if (fd <= 0) |
2ed4b548 | 4252 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4253 | |
4254 | if (offset != 0 | |
4255 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4256 | { | |
4257 | close (fd); | |
9b409511 | 4258 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4259 | } |
4260 | ||
4261 | if (writebuf) | |
4262 | ret = write (fd, writebuf, (size_t) len); | |
4263 | else if (readbuf) | |
4264 | ret = read (fd, readbuf, (size_t) len); | |
4265 | ||
4266 | close (fd); | |
9b409511 YQ |
4267 | |
4268 | if (ret < 0) | |
4269 | return TARGET_XFER_E_IO; | |
4270 | else if (ret == 0) | |
4271 | return TARGET_XFER_EOF; | |
4272 | else | |
4273 | { | |
4274 | *xfered_len = (ULONGEST) ret; | |
4275 | return TARGET_XFER_OK; | |
4276 | } | |
efcbbd14 UW |
4277 | } |
4278 | ||
4279 | ||
dba24537 AC |
4280 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4281 | ||
4282 | static void | |
4283 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4284 | { | |
4285 | int len = strlen (line) - 1; | |
4286 | const char *p; | |
4287 | int signum; | |
4288 | ||
4289 | if (line[len] != '\n') | |
8a3fe4f8 | 4290 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4291 | |
4292 | p = line; | |
4293 | signum = len * 4; | |
4294 | while (len-- > 0) | |
4295 | { | |
4296 | int digit; | |
4297 | ||
4298 | if (*p >= '0' && *p <= '9') | |
4299 | digit = *p - '0'; | |
4300 | else if (*p >= 'a' && *p <= 'f') | |
4301 | digit = *p - 'a' + 10; | |
4302 | else | |
8a3fe4f8 | 4303 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4304 | |
4305 | signum -= 4; | |
4306 | ||
4307 | if (digit & 1) | |
4308 | sigaddset (sigs, signum + 1); | |
4309 | if (digit & 2) | |
4310 | sigaddset (sigs, signum + 2); | |
4311 | if (digit & 4) | |
4312 | sigaddset (sigs, signum + 3); | |
4313 | if (digit & 8) | |
4314 | sigaddset (sigs, signum + 4); | |
4315 | ||
4316 | p++; | |
4317 | } | |
4318 | } | |
4319 | ||
4320 | /* Find process PID's pending signals from /proc/pid/status and set | |
4321 | SIGS to match. */ | |
4322 | ||
4323 | void | |
3e43a32a MS |
4324 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4325 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4326 | { |
4327 | FILE *procfile; | |
d8d2a3ee | 4328 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4329 | struct cleanup *cleanup; |
dba24537 AC |
4330 | |
4331 | sigemptyset (pending); | |
4332 | sigemptyset (blocked); | |
4333 | sigemptyset (ignored); | |
cde33bf1 | 4334 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4335 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4336 | if (procfile == NULL) |
8a3fe4f8 | 4337 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4338 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4339 | |
d8d2a3ee | 4340 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4341 | { |
4342 | /* Normal queued signals are on the SigPnd line in the status | |
4343 | file. However, 2.6 kernels also have a "shared" pending | |
4344 | queue for delivering signals to a thread group, so check for | |
4345 | a ShdPnd line also. | |
4346 | ||
4347 | Unfortunately some Red Hat kernels include the shared pending | |
4348 | queue but not the ShdPnd status field. */ | |
4349 | ||
4350 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
4351 | add_line_to_sigset (buffer + 8, pending); | |
4352 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
4353 | add_line_to_sigset (buffer + 8, pending); | |
4354 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
4355 | add_line_to_sigset (buffer + 8, blocked); | |
4356 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
4357 | add_line_to_sigset (buffer + 8, ignored); | |
4358 | } | |
4359 | ||
7c8a8b04 | 4360 | do_cleanups (cleanup); |
dba24537 AC |
4361 | } |
4362 | ||
9b409511 | 4363 | static enum target_xfer_status |
07e059b5 | 4364 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4365 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4366 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4367 | ULONGEST *xfered_len) | |
07e059b5 | 4368 | { |
07e059b5 VP |
4369 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4370 | ||
9b409511 YQ |
4371 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4372 | if (*xfered_len == 0) | |
4373 | return TARGET_XFER_EOF; | |
4374 | else | |
4375 | return TARGET_XFER_OK; | |
07e059b5 VP |
4376 | } |
4377 | ||
9b409511 | 4378 | static enum target_xfer_status |
10d6c8cd DJ |
4379 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4380 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4381 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4382 | ULONGEST *xfered_len) | |
10d6c8cd | 4383 | { |
9b409511 | 4384 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4385 | |
4386 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4387 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4388 | offset, len, xfered_len); |
10d6c8cd | 4389 | |
07e059b5 VP |
4390 | if (object == TARGET_OBJECT_OSDATA) |
4391 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4392 | offset, len, xfered_len); |
07e059b5 | 4393 | |
efcbbd14 UW |
4394 | if (object == TARGET_OBJECT_SPU) |
4395 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4396 | offset, len, xfered_len); |
efcbbd14 | 4397 | |
8f313923 JK |
4398 | /* GDB calculates all the addresses in possibly larget width of the address. |
4399 | Address width needs to be masked before its final use - either by | |
4400 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4401 | ||
4402 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4403 | ||
4404 | if (object == TARGET_OBJECT_MEMORY) | |
4405 | { | |
f5656ead | 4406 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4407 | |
4408 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4409 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4410 | } | |
4411 | ||
10d6c8cd | 4412 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4413 | offset, len, xfered_len); |
4414 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4415 | return xfer; |
4416 | ||
4417 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4418 | offset, len, xfered_len); |
10d6c8cd DJ |
4419 | } |
4420 | ||
5808517f YQ |
4421 | static void |
4422 | cleanup_target_stop (void *arg) | |
4423 | { | |
4424 | ptid_t *ptid = (ptid_t *) arg; | |
4425 | ||
4426 | gdb_assert (arg != NULL); | |
4427 | ||
4428 | /* Unpause all */ | |
a493e3e2 | 4429 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4430 | } |
4431 | ||
4432 | static VEC(static_tracepoint_marker_p) * | |
4433 | linux_child_static_tracepoint_markers_by_strid (const char *strid) | |
4434 | { | |
4435 | char s[IPA_CMD_BUF_SIZE]; | |
4436 | struct cleanup *old_chain; | |
4437 | int pid = ptid_get_pid (inferior_ptid); | |
4438 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4439 | struct static_tracepoint_marker *marker = NULL; | |
4440 | char *p = s; | |
4441 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4442 | ||
4443 | /* Pause all */ | |
4444 | target_stop (ptid); | |
4445 | ||
4446 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4447 | s[sizeof ("qTfSTM")] = 0; | |
4448 | ||
42476b70 | 4449 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4450 | |
4451 | old_chain = make_cleanup (free_current_marker, &marker); | |
4452 | make_cleanup (cleanup_target_stop, &ptid); | |
4453 | ||
4454 | while (*p++ == 'm') | |
4455 | { | |
4456 | if (marker == NULL) | |
4457 | marker = XCNEW (struct static_tracepoint_marker); | |
4458 | ||
4459 | do | |
4460 | { | |
4461 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4462 | ||
4463 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4464 | { | |
4465 | VEC_safe_push (static_tracepoint_marker_p, | |
4466 | markers, marker); | |
4467 | marker = NULL; | |
4468 | } | |
4469 | else | |
4470 | { | |
4471 | release_static_tracepoint_marker (marker); | |
4472 | memset (marker, 0, sizeof (*marker)); | |
4473 | } | |
4474 | } | |
4475 | while (*p++ == ','); /* comma-separated list */ | |
4476 | ||
4477 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4478 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4479 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4480 | p = s; |
4481 | } | |
4482 | ||
4483 | do_cleanups (old_chain); | |
4484 | ||
4485 | return markers; | |
4486 | } | |
4487 | ||
e9efe249 | 4488 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4489 | it with local methods. */ |
4490 | ||
910122bf UW |
4491 | static void |
4492 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4493 | { |
6d8fd2b7 | 4494 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4495 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4496 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4497 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4498 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4499 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4500 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4501 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4502 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4503 | t->to_post_attach = linux_child_post_attach; |
4504 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4505 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; |
4506 | ||
4507 | super_xfer_partial = t->to_xfer_partial; | |
4508 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4509 | |
4510 | t->to_static_tracepoint_markers_by_strid | |
4511 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4512 | } |
4513 | ||
4514 | struct target_ops * | |
4515 | linux_target (void) | |
4516 | { | |
4517 | struct target_ops *t; | |
4518 | ||
4519 | t = inf_ptrace_target (); | |
4520 | linux_target_install_ops (t); | |
4521 | ||
4522 | return t; | |
4523 | } | |
4524 | ||
4525 | struct target_ops * | |
7714d83a | 4526 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4527 | { |
4528 | struct target_ops *t; | |
4529 | ||
4530 | t = inf_ptrace_trad_target (register_u_offset); | |
4531 | linux_target_install_ops (t); | |
10d6c8cd | 4532 | |
10d6c8cd DJ |
4533 | return t; |
4534 | } | |
4535 | ||
b84876c2 PA |
4536 | /* target_is_async_p implementation. */ |
4537 | ||
4538 | static int | |
4539 | linux_nat_is_async_p (void) | |
4540 | { | |
4541 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4542 | it explicitly with the "set target-async" command. |
b84876c2 | 4543 | Someday, linux will always be async. */ |
3dd5b83d | 4544 | return target_async_permitted; |
b84876c2 PA |
4545 | } |
4546 | ||
4547 | /* target_can_async_p implementation. */ | |
4548 | ||
4549 | static int | |
4550 | linux_nat_can_async_p (void) | |
4551 | { | |
4552 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4553 | it explicitly with the "set target-async" command. |
b84876c2 | 4554 | Someday, linux will always be async. */ |
3dd5b83d | 4555 | return target_async_permitted; |
b84876c2 PA |
4556 | } |
4557 | ||
9908b566 VP |
4558 | static int |
4559 | linux_nat_supports_non_stop (void) | |
4560 | { | |
4561 | return 1; | |
4562 | } | |
4563 | ||
d90e17a7 PA |
4564 | /* True if we want to support multi-process. To be removed when GDB |
4565 | supports multi-exec. */ | |
4566 | ||
2277426b | 4567 | int linux_multi_process = 1; |
d90e17a7 PA |
4568 | |
4569 | static int | |
4570 | linux_nat_supports_multi_process (void) | |
4571 | { | |
4572 | return linux_multi_process; | |
4573 | } | |
4574 | ||
03583c20 UW |
4575 | static int |
4576 | linux_nat_supports_disable_randomization (void) | |
4577 | { | |
4578 | #ifdef HAVE_PERSONALITY | |
4579 | return 1; | |
4580 | #else | |
4581 | return 0; | |
4582 | #endif | |
4583 | } | |
4584 | ||
b84876c2 PA |
4585 | static int async_terminal_is_ours = 1; |
4586 | ||
4587 | /* target_terminal_inferior implementation. */ | |
4588 | ||
4589 | static void | |
4590 | linux_nat_terminal_inferior (void) | |
4591 | { | |
4592 | if (!target_is_async_p ()) | |
4593 | { | |
4594 | /* Async mode is disabled. */ | |
4595 | terminal_inferior (); | |
4596 | return; | |
4597 | } | |
4598 | ||
b84876c2 PA |
4599 | terminal_inferior (); |
4600 | ||
d9d2d8b6 | 4601 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4602 | if (!async_terminal_is_ours) |
4603 | return; | |
4604 | ||
4605 | delete_file_handler (input_fd); | |
4606 | async_terminal_is_ours = 0; | |
4607 | set_sigint_trap (); | |
4608 | } | |
4609 | ||
4610 | /* target_terminal_ours implementation. */ | |
4611 | ||
2c0b251b | 4612 | static void |
b84876c2 PA |
4613 | linux_nat_terminal_ours (void) |
4614 | { | |
4615 | if (!target_is_async_p ()) | |
4616 | { | |
4617 | /* Async mode is disabled. */ | |
4618 | terminal_ours (); | |
4619 | return; | |
4620 | } | |
4621 | ||
4622 | /* GDB should never give the terminal to the inferior if the | |
4623 | inferior is running in the background (run&, continue&, etc.), | |
4624 | but claiming it sure should. */ | |
4625 | terminal_ours (); | |
4626 | ||
b84876c2 PA |
4627 | if (async_terminal_is_ours) |
4628 | return; | |
4629 | ||
4630 | clear_sigint_trap (); | |
4631 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4632 | async_terminal_is_ours = 1; | |
4633 | } | |
4634 | ||
4635 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4636 | void *context); | |
4637 | static void *async_client_context; | |
4638 | ||
7feb7d06 PA |
4639 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4640 | so we notice when any child changes state, and notify the | |
4641 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4642 | above to wait for the arrival of a SIGCHLD. */ | |
4643 | ||
b84876c2 | 4644 | static void |
7feb7d06 | 4645 | sigchld_handler (int signo) |
b84876c2 | 4646 | { |
7feb7d06 PA |
4647 | int old_errno = errno; |
4648 | ||
01124a23 DE |
4649 | if (debug_linux_nat) |
4650 | ui_file_write_async_safe (gdb_stdlog, | |
4651 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4652 | |
4653 | if (signo == SIGCHLD | |
4654 | && linux_nat_event_pipe[0] != -1) | |
4655 | async_file_mark (); /* Let the event loop know that there are | |
4656 | events to handle. */ | |
4657 | ||
4658 | errno = old_errno; | |
4659 | } | |
4660 | ||
4661 | /* Callback registered with the target events file descriptor. */ | |
4662 | ||
4663 | static void | |
4664 | handle_target_event (int error, gdb_client_data client_data) | |
4665 | { | |
4666 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4667 | } | |
4668 | ||
4669 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4670 | ||
4671 | static int | |
4672 | linux_async_pipe (int enable) | |
4673 | { | |
4674 | int previous = (linux_nat_event_pipe[0] != -1); | |
4675 | ||
4676 | if (previous != enable) | |
4677 | { | |
4678 | sigset_t prev_mask; | |
4679 | ||
12696c10 PA |
4680 | /* Block child signals while we create/destroy the pipe, as |
4681 | their handler writes to it. */ | |
7feb7d06 PA |
4682 | block_child_signals (&prev_mask); |
4683 | ||
4684 | if (enable) | |
4685 | { | |
614c279d | 4686 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4687 | internal_error (__FILE__, __LINE__, |
4688 | "creating event pipe failed."); | |
4689 | ||
4690 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4691 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4692 | } | |
4693 | else | |
4694 | { | |
4695 | close (linux_nat_event_pipe[0]); | |
4696 | close (linux_nat_event_pipe[1]); | |
4697 | linux_nat_event_pipe[0] = -1; | |
4698 | linux_nat_event_pipe[1] = -1; | |
4699 | } | |
4700 | ||
4701 | restore_child_signals_mask (&prev_mask); | |
4702 | } | |
4703 | ||
4704 | return previous; | |
b84876c2 PA |
4705 | } |
4706 | ||
4707 | /* target_async implementation. */ | |
4708 | ||
4709 | static void | |
4710 | linux_nat_async (void (*callback) (enum inferior_event_type event_type, | |
4711 | void *context), void *context) | |
4712 | { | |
b84876c2 PA |
4713 | if (callback != NULL) |
4714 | { | |
4715 | async_client_callback = callback; | |
4716 | async_client_context = context; | |
7feb7d06 PA |
4717 | if (!linux_async_pipe (1)) |
4718 | { | |
4719 | add_file_handler (linux_nat_event_pipe[0], | |
4720 | handle_target_event, NULL); | |
4721 | /* There may be pending events to handle. Tell the event loop | |
4722 | to poll them. */ | |
4723 | async_file_mark (); | |
4724 | } | |
b84876c2 PA |
4725 | } |
4726 | else | |
4727 | { | |
4728 | async_client_callback = callback; | |
4729 | async_client_context = context; | |
b84876c2 | 4730 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4731 | linux_async_pipe (0); |
b84876c2 PA |
4732 | } |
4733 | return; | |
4734 | } | |
4735 | ||
a493e3e2 | 4736 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4737 | event came out. */ |
4738 | ||
4c28f408 | 4739 | static int |
252fbfc8 | 4740 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4741 | { |
d90e17a7 | 4742 | if (!lwp->stopped) |
252fbfc8 | 4743 | { |
d90e17a7 PA |
4744 | if (debug_linux_nat) |
4745 | fprintf_unfiltered (gdb_stdlog, | |
4746 | "LNSL: running -> suspending %s\n", | |
4747 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4748 | |
252fbfc8 | 4749 | |
25289eb2 PA |
4750 | if (lwp->last_resume_kind == resume_stop) |
4751 | { | |
4752 | if (debug_linux_nat) | |
4753 | fprintf_unfiltered (gdb_stdlog, | |
4754 | "linux-nat: already stopping LWP %ld at " | |
4755 | "GDB's request\n", | |
4756 | ptid_get_lwp (lwp->ptid)); | |
4757 | return 0; | |
4758 | } | |
252fbfc8 | 4759 | |
25289eb2 PA |
4760 | stop_callback (lwp, NULL); |
4761 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4762 | } |
4763 | else | |
4764 | { | |
4765 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4766 | |
d90e17a7 PA |
4767 | if (debug_linux_nat) |
4768 | { | |
e09875d4 | 4769 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4770 | fprintf_unfiltered (gdb_stdlog, |
4771 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4772 | target_pid_to_str (lwp->ptid)); |
4773 | else | |
3e43a32a MS |
4774 | fprintf_unfiltered (gdb_stdlog, |
4775 | "LNSL: already stopped/no " | |
4776 | "stop_requested yet %s\n", | |
d90e17a7 | 4777 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4778 | } |
4779 | } | |
4c28f408 PA |
4780 | return 0; |
4781 | } | |
4782 | ||
4783 | static void | |
4784 | linux_nat_stop (ptid_t ptid) | |
4785 | { | |
4786 | if (non_stop) | |
d90e17a7 | 4787 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 PA |
4788 | else |
4789 | linux_ops->to_stop (ptid); | |
4790 | } | |
4791 | ||
d90e17a7 | 4792 | static void |
460014f5 | 4793 | linux_nat_close (void) |
d90e17a7 PA |
4794 | { |
4795 | /* Unregister from the event loop. */ | |
305436e0 PA |
4796 | if (linux_nat_is_async_p ()) |
4797 | linux_nat_async (NULL, 0); | |
d90e17a7 | 4798 | |
d90e17a7 | 4799 | if (linux_ops->to_close) |
460014f5 | 4800 | linux_ops->to_close (); |
d90e17a7 PA |
4801 | } |
4802 | ||
c0694254 PA |
4803 | /* When requests are passed down from the linux-nat layer to the |
4804 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4805 | used. The address space pointer is stored in the inferior object, | |
4806 | but the common code that is passed such ptid can't tell whether | |
4807 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4808 | look up the "main" process id from the lwp here. */ | |
4809 | ||
70221824 | 4810 | static struct address_space * |
c0694254 PA |
4811 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4812 | { | |
4813 | struct lwp_info *lwp; | |
4814 | struct inferior *inf; | |
4815 | int pid; | |
4816 | ||
dfd4cc63 LM |
4817 | pid = ptid_get_lwp (ptid); |
4818 | if (ptid_get_lwp (ptid) == 0) | |
c0694254 PA |
4819 | { |
4820 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4821 | tgid. */ | |
4822 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4823 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4824 | } |
4825 | else | |
4826 | { | |
4827 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4828 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4829 | } |
4830 | ||
4831 | inf = find_inferior_pid (pid); | |
4832 | gdb_assert (inf != NULL); | |
4833 | return inf->aspace; | |
4834 | } | |
4835 | ||
dc146f7c VP |
4836 | /* Return the cached value of the processor core for thread PTID. */ |
4837 | ||
70221824 | 4838 | static int |
dc146f7c VP |
4839 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4840 | { | |
4841 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4842 | |
dc146f7c VP |
4843 | if (info) |
4844 | return info->core; | |
4845 | return -1; | |
4846 | } | |
4847 | ||
f973ed9c DJ |
4848 | void |
4849 | linux_nat_add_target (struct target_ops *t) | |
4850 | { | |
f973ed9c DJ |
4851 | /* Save the provided single-threaded target. We save this in a separate |
4852 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4853 | may have saved a pointer to T; we want to use it for the final | |
4854 | process stratum target. */ | |
4855 | linux_ops_saved = *t; | |
4856 | linux_ops = &linux_ops_saved; | |
4857 | ||
4858 | /* Override some methods for multithreading. */ | |
b84876c2 | 4859 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4860 | t->to_attach = linux_nat_attach; |
4861 | t->to_detach = linux_nat_detach; | |
4862 | t->to_resume = linux_nat_resume; | |
4863 | t->to_wait = linux_nat_wait; | |
2455069d | 4864 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4865 | t->to_xfer_partial = linux_nat_xfer_partial; |
4866 | t->to_kill = linux_nat_kill; | |
4867 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4868 | t->to_thread_alive = linux_nat_thread_alive; | |
4869 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4870 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4871 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4872 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4873 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4874 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
f973ed9c | 4875 | |
b84876c2 PA |
4876 | t->to_can_async_p = linux_nat_can_async_p; |
4877 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4878 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4879 | t->to_async = linux_nat_async; |
b84876c2 PA |
4880 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4881 | t->to_terminal_ours = linux_nat_terminal_ours; | |
d90e17a7 | 4882 | t->to_close = linux_nat_close; |
b84876c2 | 4883 | |
4c28f408 PA |
4884 | /* Methods for non-stop support. */ |
4885 | t->to_stop = linux_nat_stop; | |
4886 | ||
d90e17a7 PA |
4887 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4888 | ||
03583c20 UW |
4889 | t->to_supports_disable_randomization |
4890 | = linux_nat_supports_disable_randomization; | |
4891 | ||
dc146f7c VP |
4892 | t->to_core_of_thread = linux_nat_core_of_thread; |
4893 | ||
f973ed9c DJ |
4894 | /* We don't change the stratum; this target will sit at |
4895 | process_stratum and thread_db will set at thread_stratum. This | |
4896 | is a little strange, since this is a multi-threaded-capable | |
4897 | target, but we want to be on the stack below thread_db, and we | |
4898 | also want to be used for single-threaded processes. */ | |
4899 | ||
4900 | add_target (t); | |
f973ed9c DJ |
4901 | } |
4902 | ||
9f0bdab8 DJ |
4903 | /* Register a method to call whenever a new thread is attached. */ |
4904 | void | |
7b50312a PA |
4905 | linux_nat_set_new_thread (struct target_ops *t, |
4906 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4907 | { |
4908 | /* Save the pointer. We only support a single registered instance | |
4909 | of the GNU/Linux native target, so we do not need to map this to | |
4910 | T. */ | |
4911 | linux_nat_new_thread = new_thread; | |
4912 | } | |
4913 | ||
26cb8b7c PA |
4914 | /* See declaration in linux-nat.h. */ |
4915 | ||
4916 | void | |
4917 | linux_nat_set_new_fork (struct target_ops *t, | |
4918 | linux_nat_new_fork_ftype *new_fork) | |
4919 | { | |
4920 | /* Save the pointer. */ | |
4921 | linux_nat_new_fork = new_fork; | |
4922 | } | |
4923 | ||
4924 | /* See declaration in linux-nat.h. */ | |
4925 | ||
4926 | void | |
4927 | linux_nat_set_forget_process (struct target_ops *t, | |
4928 | linux_nat_forget_process_ftype *fn) | |
4929 | { | |
4930 | /* Save the pointer. */ | |
4931 | linux_nat_forget_process_hook = fn; | |
4932 | } | |
4933 | ||
4934 | /* See declaration in linux-nat.h. */ | |
4935 | ||
4936 | void | |
4937 | linux_nat_forget_process (pid_t pid) | |
4938 | { | |
4939 | if (linux_nat_forget_process_hook != NULL) | |
4940 | linux_nat_forget_process_hook (pid); | |
4941 | } | |
4942 | ||
5b009018 PA |
4943 | /* Register a method that converts a siginfo object between the layout |
4944 | that ptrace returns, and the layout in the architecture of the | |
4945 | inferior. */ | |
4946 | void | |
4947 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4948 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4949 | gdb_byte *, |
4950 | int)) | |
4951 | { | |
4952 | /* Save the pointer. */ | |
4953 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4954 | } | |
4955 | ||
7b50312a PA |
4956 | /* Register a method to call prior to resuming a thread. */ |
4957 | ||
4958 | void | |
4959 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4960 | void (*prepare_to_resume) (struct lwp_info *)) | |
4961 | { | |
4962 | /* Save the pointer. */ | |
4963 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4964 | } | |
4965 | ||
f865ee35 JK |
4966 | /* See linux-nat.h. */ |
4967 | ||
4968 | int | |
4969 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4970 | { |
da559b09 | 4971 | int pid; |
9f0bdab8 | 4972 | |
dfd4cc63 | 4973 | pid = ptid_get_lwp (ptid); |
da559b09 | 4974 | if (pid == 0) |
dfd4cc63 | 4975 | pid = ptid_get_pid (ptid); |
f865ee35 | 4976 | |
da559b09 JK |
4977 | errno = 0; |
4978 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4979 | if (errno != 0) | |
4980 | { | |
4981 | memset (siginfo, 0, sizeof (*siginfo)); | |
4982 | return 0; | |
4983 | } | |
f865ee35 | 4984 | return 1; |
9f0bdab8 DJ |
4985 | } |
4986 | ||
2c0b251b PA |
4987 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4988 | extern initialize_file_ftype _initialize_linux_nat; | |
4989 | ||
d6b0e80f AC |
4990 | void |
4991 | _initialize_linux_nat (void) | |
4992 | { | |
ccce17b0 YQ |
4993 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4994 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4995 | Set debugging of GNU/Linux lwp module."), _("\ |
4996 | Show debugging of GNU/Linux lwp module."), _("\ | |
4997 | Enables printf debugging output."), | |
ccce17b0 YQ |
4998 | NULL, |
4999 | show_debug_linux_nat, | |
5000 | &setdebuglist, &showdebuglist); | |
b84876c2 | 5001 | |
b84876c2 | 5002 | /* Save this mask as the default. */ |
d6b0e80f AC |
5003 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
5004 | ||
7feb7d06 PA |
5005 | /* Install a SIGCHLD handler. */ |
5006 | sigchld_action.sa_handler = sigchld_handler; | |
5007 | sigemptyset (&sigchld_action.sa_mask); | |
5008 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
5009 | |
5010 | /* Make it the default. */ | |
7feb7d06 | 5011 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5012 | |
5013 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5014 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5015 | sigdelset (&suspend_mask, SIGCHLD); | |
5016 | ||
7feb7d06 | 5017 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5018 | } |
5019 | \f | |
5020 | ||
5021 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5022 | the GNU/Linux Threads library and therefore doesn't really belong | |
5023 | here. */ | |
5024 | ||
5025 | /* Read variable NAME in the target and return its value if found. | |
5026 | Otherwise return zero. It is assumed that the type of the variable | |
5027 | is `int'. */ | |
5028 | ||
5029 | static int | |
5030 | get_signo (const char *name) | |
5031 | { | |
5032 | struct minimal_symbol *ms; | |
5033 | int signo; | |
5034 | ||
5035 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
5036 | if (ms == NULL) | |
5037 | return 0; | |
5038 | ||
8e70166d | 5039 | if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5040 | sizeof (signo)) != 0) |
5041 | return 0; | |
5042 | ||
5043 | return signo; | |
5044 | } | |
5045 | ||
5046 | /* Return the set of signals used by the threads library in *SET. */ | |
5047 | ||
5048 | void | |
5049 | lin_thread_get_thread_signals (sigset_t *set) | |
5050 | { | |
5051 | struct sigaction action; | |
5052 | int restart, cancel; | |
5053 | ||
b84876c2 | 5054 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5055 | sigemptyset (set); |
5056 | ||
5057 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5058 | cancel = get_signo ("__pthread_sig_cancel"); |
5059 | ||
5060 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5061 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5062 | not provide any way for the debugger to query the signal numbers - | |
5063 | fortunately they don't change! */ | |
5064 | ||
d6b0e80f | 5065 | if (restart == 0) |
17fbb0bd | 5066 | restart = __SIGRTMIN; |
d6b0e80f | 5067 | |
d6b0e80f | 5068 | if (cancel == 0) |
17fbb0bd | 5069 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5070 | |
5071 | sigaddset (set, restart); | |
5072 | sigaddset (set, cancel); | |
5073 | ||
5074 | /* The GNU/Linux Threads library makes terminating threads send a | |
5075 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5076 | those (to prevent them from terminating GDB itself, which is | |
5077 | likely to be their default action) and treat them the same way as | |
5078 | SIGCHLD. */ | |
5079 | ||
5080 | action.sa_handler = sigchld_handler; | |
5081 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5082 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5083 | sigaction (cancel, &action, NULL); |
5084 | ||
5085 | /* We block the "cancel" signal throughout this code ... */ | |
5086 | sigaddset (&blocked_mask, cancel); | |
5087 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5088 | ||
5089 | /* ... except during a sigsuspend. */ | |
5090 | sigdelset (&suspend_mask, cancel); | |
5091 | } |