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3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
32d0add0 | 3 | Copyright (C) 2001-2015 Free Software Foundation, Inc. |
3993f6b1 DJ |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
3993f6b1 DJ |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3993f6b1 DJ |
19 | |
20 | #include "defs.h" | |
21 | #include "inferior.h" | |
45741a9c | 22 | #include "infrun.h" |
3993f6b1 | 23 | #include "target.h" |
96d7229d LM |
24 | #include "nat/linux-nat.h" |
25 | #include "nat/linux-waitpid.h" | |
3993f6b1 | 26 | #include "gdb_wait.h" |
d6b0e80f AC |
27 | #ifdef HAVE_TKILL_SYSCALL |
28 | #include <unistd.h> | |
29 | #include <sys/syscall.h> | |
30 | #endif | |
3993f6b1 | 31 | #include <sys/ptrace.h> |
0274a8ce | 32 | #include "linux-nat.h" |
125f8a3d GB |
33 | #include "nat/linux-ptrace.h" |
34 | #include "nat/linux-procfs.h" | |
8cc73a39 | 35 | #include "nat/linux-personality.h" |
ac264b3b | 36 | #include "linux-fork.h" |
d6b0e80f AC |
37 | #include "gdbthread.h" |
38 | #include "gdbcmd.h" | |
39 | #include "regcache.h" | |
4f844a66 | 40 | #include "regset.h" |
dab06dbe | 41 | #include "inf-child.h" |
10d6c8cd DJ |
42 | #include "inf-ptrace.h" |
43 | #include "auxv.h" | |
1777feb0 | 44 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
45 | #include "elf-bfd.h" /* for elfcore_write_* */ |
46 | #include "gregset.h" /* for gregset */ | |
47 | #include "gdbcore.h" /* for get_exec_file */ | |
48 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 49 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 50 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
51 | #include "inf-loop.h" |
52 | #include "event-loop.h" | |
53 | #include "event-top.h" | |
07e059b5 VP |
54 | #include <pwd.h> |
55 | #include <sys/types.h> | |
2978b111 | 56 | #include <dirent.h> |
07e059b5 | 57 | #include "xml-support.h" |
efcbbd14 | 58 | #include <sys/vfs.h> |
6c95b8df | 59 | #include "solib.h" |
125f8a3d | 60 | #include "nat/linux-osdata.h" |
6432734d | 61 | #include "linux-tdep.h" |
7dcd53a0 | 62 | #include "symfile.h" |
5808517f YQ |
63 | #include "agent.h" |
64 | #include "tracepoint.h" | |
87b0bb13 | 65 | #include "buffer.h" |
6ecd4729 | 66 | #include "target-descriptions.h" |
614c279d | 67 | #include "filestuff.h" |
77e371c0 | 68 | #include "objfiles.h" |
efcbbd14 UW |
69 | |
70 | #ifndef SPUFS_MAGIC | |
71 | #define SPUFS_MAGIC 0x23c9b64e | |
72 | #endif | |
dba24537 | 73 | |
1777feb0 | 74 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
75 | |
76 | Waiting for events in sync mode | |
77 | =============================== | |
78 | ||
79 | When waiting for an event in a specific thread, we just use waitpid, passing | |
80 | the specific pid, and not passing WNOHANG. | |
81 | ||
1777feb0 | 82 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 83 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 84 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
85 | miss an event. The solution is to use non-blocking waitpid, together with |
86 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 87 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
88 | flag to check for events in cloned processes. If nothing is found, we use |
89 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
90 | happened to a child process -- and SIGCHLD will be delivered both for events | |
91 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
92 | an event, we get back to calling nonblocking waitpid with and without |
93 | __WCLONED. | |
8a77dff3 VP |
94 | |
95 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 96 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
97 | blocked, the signal becomes pending and sigsuspend immediately |
98 | notices it and returns. | |
99 | ||
100 | Waiting for events in async mode | |
101 | ================================ | |
102 | ||
7feb7d06 PA |
103 | In async mode, GDB should always be ready to handle both user input |
104 | and target events, so neither blocking waitpid nor sigsuspend are | |
105 | viable options. Instead, we should asynchronously notify the GDB main | |
106 | event loop whenever there's an unprocessed event from the target. We | |
107 | detect asynchronous target events by handling SIGCHLD signals. To | |
108 | notify the event loop about target events, the self-pipe trick is used | |
109 | --- a pipe is registered as waitable event source in the event loop, | |
110 | the event loop select/poll's on the read end of this pipe (as well on | |
111 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
112 | byte to this pipe. This is more portable than relying on | |
113 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
114 | emulates them with select/poll+sigprocmask, and that is racy | |
115 | (a.k.a. plain broken). | |
116 | ||
117 | Obviously, if we fail to notify the event loop if there's a target | |
118 | event, it's bad. OTOH, if we notify the event loop when there's no | |
119 | event from the target, linux_nat_wait will detect that there's no real | |
120 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
121 | This is mostly harmless, but it will waste time and is better avoided. | |
122 | ||
123 | The main design point is that every time GDB is outside linux-nat.c, | |
124 | we have a SIGCHLD handler installed that is called when something | |
125 | happens to the target and notifies the GDB event loop. Whenever GDB | |
126 | core decides to handle the event, and calls into linux-nat.c, we | |
127 | process things as in sync mode, except that the we never block in | |
128 | sigsuspend. | |
129 | ||
130 | While processing an event, we may end up momentarily blocked in | |
131 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
132 | return quickly. E.g., in all-stop mode, before reporting to the core | |
133 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
134 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
135 | Note that this is different from blocking indefinitely waiting for the | |
136 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
137 | |
138 | Use of signals | |
139 | ============== | |
140 | ||
141 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
142 | signal is not entirely significant; we just need for a signal to be delivered, | |
143 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
144 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
145 | be queued once; we do not keep track of other sources of SIGSTOP. | |
146 | ||
147 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
148 | use them, because they have special behavior when the signal is generated - | |
149 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
150 | kills the entire thread group. | |
151 | ||
152 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
153 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
154 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
155 | ||
156 | We could use a real-time signal instead. This would solve those problems; we | |
157 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
158 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
159 | generates it, and there are races with trying to find a signal that is not | |
160 | blocked. */ | |
a0ef4274 | 161 | |
dba24537 AC |
162 | #ifndef O_LARGEFILE |
163 | #define O_LARGEFILE 0 | |
164 | #endif | |
0274a8ce | 165 | |
10d6c8cd DJ |
166 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
167 | the use of the multi-threaded target. */ | |
168 | static struct target_ops *linux_ops; | |
f973ed9c | 169 | static struct target_ops linux_ops_saved; |
10d6c8cd | 170 | |
9f0bdab8 | 171 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
172 | static void (*linux_nat_new_thread) (struct lwp_info *); |
173 | ||
26cb8b7c PA |
174 | /* The method to call, if any, when a new fork is attached. */ |
175 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
176 | ||
177 | /* The method to call, if any, when a process is no longer | |
178 | attached. */ | |
179 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
180 | ||
7b50312a PA |
181 | /* Hook to call prior to resuming a thread. */ |
182 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 183 | |
5b009018 PA |
184 | /* The method to call, if any, when the siginfo object needs to be |
185 | converted between the layout returned by ptrace, and the layout in | |
186 | the architecture of the inferior. */ | |
a5362b9a | 187 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
188 | gdb_byte *, |
189 | int); | |
190 | ||
ac264b3b MS |
191 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
192 | Called by our to_xfer_partial. */ | |
4ac248ca | 193 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 194 | |
6a3cb8e8 PA |
195 | /* The saved to_close method, inherited from inf-ptrace.c. |
196 | Called by our to_close. */ | |
197 | static void (*super_close) (struct target_ops *); | |
198 | ||
ccce17b0 | 199 | static unsigned int debug_linux_nat; |
920d2a44 AC |
200 | static void |
201 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
202 | struct cmd_list_element *c, const char *value) | |
203 | { | |
204 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
205 | value); | |
206 | } | |
d6b0e80f | 207 | |
ae087d01 DJ |
208 | struct simple_pid_list |
209 | { | |
210 | int pid; | |
3d799a95 | 211 | int status; |
ae087d01 DJ |
212 | struct simple_pid_list *next; |
213 | }; | |
214 | struct simple_pid_list *stopped_pids; | |
215 | ||
3dd5b83d PA |
216 | /* Async mode support. */ |
217 | ||
b84876c2 PA |
218 | /* The read/write ends of the pipe registered as waitable file in the |
219 | event loop. */ | |
220 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
221 | ||
198297aa PA |
222 | /* True if we're currently in async mode. */ |
223 | #define linux_is_async_p() (linux_nat_event_pipe[0] != -1) | |
224 | ||
7feb7d06 | 225 | /* Flush the event pipe. */ |
b84876c2 | 226 | |
7feb7d06 PA |
227 | static void |
228 | async_file_flush (void) | |
b84876c2 | 229 | { |
7feb7d06 PA |
230 | int ret; |
231 | char buf; | |
b84876c2 | 232 | |
7feb7d06 | 233 | do |
b84876c2 | 234 | { |
7feb7d06 | 235 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 236 | } |
7feb7d06 | 237 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
238 | } |
239 | ||
7feb7d06 PA |
240 | /* Put something (anything, doesn't matter what, or how much) in event |
241 | pipe, so that the select/poll in the event-loop realizes we have | |
242 | something to process. */ | |
252fbfc8 | 243 | |
b84876c2 | 244 | static void |
7feb7d06 | 245 | async_file_mark (void) |
b84876c2 | 246 | { |
7feb7d06 | 247 | int ret; |
b84876c2 | 248 | |
7feb7d06 PA |
249 | /* It doesn't really matter what the pipe contains, as long we end |
250 | up with something in it. Might as well flush the previous | |
251 | left-overs. */ | |
252 | async_file_flush (); | |
b84876c2 | 253 | |
7feb7d06 | 254 | do |
b84876c2 | 255 | { |
7feb7d06 | 256 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 257 | } |
7feb7d06 | 258 | while (ret == -1 && errno == EINTR); |
b84876c2 | 259 | |
7feb7d06 PA |
260 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
261 | be awakened anyway. */ | |
b84876c2 PA |
262 | } |
263 | ||
7feb7d06 PA |
264 | static int kill_lwp (int lwpid, int signo); |
265 | ||
266 | static int stop_callback (struct lwp_info *lp, void *data); | |
2db9a427 | 267 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
7feb7d06 PA |
268 | |
269 | static void block_child_signals (sigset_t *prev_mask); | |
270 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
271 | |
272 | struct lwp_info; | |
273 | static struct lwp_info *add_lwp (ptid_t ptid); | |
274 | static void purge_lwp_list (int pid); | |
4403d8e9 | 275 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
276 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
277 | ||
8a99810d PA |
278 | static int lwp_status_pending_p (struct lwp_info *lp); |
279 | ||
9c02b525 PA |
280 | static int check_stopped_by_breakpoint (struct lwp_info *lp); |
281 | static int sigtrap_is_event (int status); | |
282 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
283 | ||
ae087d01 DJ |
284 | \f |
285 | /* Trivial list manipulation functions to keep track of a list of | |
286 | new stopped processes. */ | |
287 | static void | |
3d799a95 | 288 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
289 | { |
290 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 291 | |
ae087d01 | 292 | new_pid->pid = pid; |
3d799a95 | 293 | new_pid->status = status; |
ae087d01 DJ |
294 | new_pid->next = *listp; |
295 | *listp = new_pid; | |
296 | } | |
297 | ||
84636d28 PA |
298 | static int |
299 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
300 | { | |
301 | struct simple_pid_list *p; | |
302 | ||
303 | for (p = list; p != NULL; p = p->next) | |
304 | if (p->pid == pid) | |
305 | return 1; | |
306 | return 0; | |
307 | } | |
308 | ||
ae087d01 | 309 | static int |
46a96992 | 310 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
311 | { |
312 | struct simple_pid_list **p; | |
313 | ||
314 | for (p = listp; *p != NULL; p = &(*p)->next) | |
315 | if ((*p)->pid == pid) | |
316 | { | |
317 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 318 | |
46a96992 | 319 | *statusp = (*p)->status; |
ae087d01 DJ |
320 | xfree (*p); |
321 | *p = next; | |
322 | return 1; | |
323 | } | |
324 | return 0; | |
325 | } | |
326 | ||
96d7229d | 327 | /* Initialize ptrace warnings and check for supported ptrace |
beed38b8 JB |
328 | features given PID. |
329 | ||
330 | ATTACHED should be nonzero iff we attached to the inferior. */ | |
3993f6b1 DJ |
331 | |
332 | static void | |
beed38b8 | 333 | linux_init_ptrace (pid_t pid, int attached) |
3993f6b1 | 334 | { |
beed38b8 | 335 | linux_enable_event_reporting (pid, attached); |
96d7229d | 336 | linux_ptrace_init_warnings (); |
4de4c07c DJ |
337 | } |
338 | ||
6d8fd2b7 | 339 | static void |
f045800c | 340 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 341 | { |
beed38b8 | 342 | linux_init_ptrace (pid, 1); |
4de4c07c DJ |
343 | } |
344 | ||
10d6c8cd | 345 | static void |
2e97a79e | 346 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 347 | { |
beed38b8 | 348 | linux_init_ptrace (ptid_get_pid (ptid), 0); |
4de4c07c DJ |
349 | } |
350 | ||
4403d8e9 JK |
351 | /* Return the number of known LWPs in the tgid given by PID. */ |
352 | ||
353 | static int | |
354 | num_lwps (int pid) | |
355 | { | |
356 | int count = 0; | |
357 | struct lwp_info *lp; | |
358 | ||
359 | for (lp = lwp_list; lp; lp = lp->next) | |
360 | if (ptid_get_pid (lp->ptid) == pid) | |
361 | count++; | |
362 | ||
363 | return count; | |
364 | } | |
365 | ||
366 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
367 | ||
368 | static void | |
369 | delete_lwp_cleanup (void *lp_voidp) | |
370 | { | |
371 | struct lwp_info *lp = lp_voidp; | |
372 | ||
373 | delete_lwp (lp->ptid); | |
374 | } | |
375 | ||
d83ad864 DB |
376 | /* Target hook for follow_fork. On entry inferior_ptid must be the |
377 | ptid of the followed inferior. At return, inferior_ptid will be | |
378 | unchanged. */ | |
379 | ||
6d8fd2b7 | 380 | static int |
07107ca6 LM |
381 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
382 | int detach_fork) | |
3993f6b1 | 383 | { |
d83ad864 | 384 | if (!follow_child) |
4de4c07c | 385 | { |
6c95b8df | 386 | struct lwp_info *child_lp = NULL; |
d83ad864 DB |
387 | int status = W_STOPCODE (0); |
388 | struct cleanup *old_chain; | |
389 | int has_vforked; | |
79639e11 | 390 | ptid_t parent_ptid, child_ptid; |
d83ad864 DB |
391 | int parent_pid, child_pid; |
392 | ||
393 | has_vforked = (inferior_thread ()->pending_follow.kind | |
394 | == TARGET_WAITKIND_VFORKED); | |
79639e11 PA |
395 | parent_ptid = inferior_ptid; |
396 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; | |
397 | parent_pid = ptid_get_lwp (parent_ptid); | |
398 | child_pid = ptid_get_lwp (child_ptid); | |
4de4c07c | 399 | |
1777feb0 | 400 | /* We're already attached to the parent, by default. */ |
d83ad864 | 401 | old_chain = save_inferior_ptid (); |
79639e11 | 402 | inferior_ptid = child_ptid; |
d83ad864 DB |
403 | child_lp = add_lwp (inferior_ptid); |
404 | child_lp->stopped = 1; | |
405 | child_lp->last_resume_kind = resume_stop; | |
4de4c07c | 406 | |
ac264b3b MS |
407 | /* Detach new forked process? */ |
408 | if (detach_fork) | |
f75c00e4 | 409 | { |
4403d8e9 JK |
410 | make_cleanup (delete_lwp_cleanup, child_lp); |
411 | ||
4403d8e9 JK |
412 | if (linux_nat_prepare_to_resume != NULL) |
413 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
414 | |
415 | /* When debugging an inferior in an architecture that supports | |
416 | hardware single stepping on a kernel without commit | |
417 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
418 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
419 | set if the parent process had them set. | |
420 | To work around this, single step the child process | |
421 | once before detaching to clear the flags. */ | |
422 | ||
423 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
424 | (child_lp->ptid))) | |
425 | { | |
c077881a HZ |
426 | linux_disable_event_reporting (child_pid); |
427 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
428 | perror_with_name (_("Couldn't do single step")); | |
429 | if (my_waitpid (child_pid, &status, 0) < 0) | |
430 | perror_with_name (_("Couldn't wait vfork process")); | |
431 | } | |
432 | ||
433 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
434 | { |
435 | int signo; | |
436 | ||
437 | signo = WSTOPSIG (status); | |
438 | if (signo != 0 | |
439 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
440 | signo = 0; | |
441 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
442 | } | |
4403d8e9 | 443 | |
d83ad864 | 444 | /* Resets value of inferior_ptid to parent ptid. */ |
4403d8e9 | 445 | do_cleanups (old_chain); |
ac264b3b MS |
446 | } |
447 | else | |
448 | { | |
6c95b8df | 449 | /* Let the thread_db layer learn about this new process. */ |
2277426b | 450 | check_for_thread_db (); |
ac264b3b | 451 | } |
9016a515 | 452 | |
d83ad864 DB |
453 | do_cleanups (old_chain); |
454 | ||
9016a515 DJ |
455 | if (has_vforked) |
456 | { | |
3ced3da4 | 457 | struct lwp_info *parent_lp; |
6c95b8df | 458 | |
79639e11 | 459 | parent_lp = find_lwp_pid (parent_ptid); |
96d7229d | 460 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 461 | |
96d7229d | 462 | if (linux_supports_tracevforkdone ()) |
9016a515 | 463 | { |
6c95b8df PA |
464 | if (debug_linux_nat) |
465 | fprintf_unfiltered (gdb_stdlog, | |
466 | "LCFF: waiting for VFORK_DONE on %d\n", | |
467 | parent_pid); | |
3ced3da4 | 468 | parent_lp->stopped = 1; |
9016a515 | 469 | |
6c95b8df PA |
470 | /* We'll handle the VFORK_DONE event like any other |
471 | event, in target_wait. */ | |
9016a515 DJ |
472 | } |
473 | else | |
474 | { | |
475 | /* We can't insert breakpoints until the child has | |
476 | finished with the shared memory region. We need to | |
477 | wait until that happens. Ideal would be to just | |
478 | call: | |
479 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
480 | - waitpid (parent_pid, &status, __WALL); | |
481 | However, most architectures can't handle a syscall | |
482 | being traced on the way out if it wasn't traced on | |
483 | the way in. | |
484 | ||
485 | We might also think to loop, continuing the child | |
486 | until it exits or gets a SIGTRAP. One problem is | |
487 | that the child might call ptrace with PTRACE_TRACEME. | |
488 | ||
489 | There's no simple and reliable way to figure out when | |
490 | the vforked child will be done with its copy of the | |
491 | shared memory. We could step it out of the syscall, | |
492 | two instructions, let it go, and then single-step the | |
493 | parent once. When we have hardware single-step, this | |
494 | would work; with software single-step it could still | |
495 | be made to work but we'd have to be able to insert | |
496 | single-step breakpoints in the child, and we'd have | |
497 | to insert -just- the single-step breakpoint in the | |
498 | parent. Very awkward. | |
499 | ||
500 | In the end, the best we can do is to make sure it | |
501 | runs for a little while. Hopefully it will be out of | |
502 | range of any breakpoints we reinsert. Usually this | |
503 | is only the single-step breakpoint at vfork's return | |
504 | point. */ | |
505 | ||
6c95b8df PA |
506 | if (debug_linux_nat) |
507 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
508 | "LCFF: no VFORK_DONE " |
509 | "support, sleeping a bit\n"); | |
6c95b8df | 510 | |
9016a515 | 511 | usleep (10000); |
9016a515 | 512 | |
6c95b8df PA |
513 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
514 | and leave it pending. The next linux_nat_resume call | |
515 | will notice a pending event, and bypasses actually | |
516 | resuming the inferior. */ | |
3ced3da4 PA |
517 | parent_lp->status = 0; |
518 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
519 | parent_lp->stopped = 1; | |
6c95b8df PA |
520 | |
521 | /* If we're in async mode, need to tell the event loop | |
522 | there's something here to process. */ | |
d9d41e78 | 523 | if (target_is_async_p ()) |
6c95b8df PA |
524 | async_file_mark (); |
525 | } | |
9016a515 | 526 | } |
4de4c07c | 527 | } |
3993f6b1 | 528 | else |
4de4c07c | 529 | { |
3ced3da4 | 530 | struct lwp_info *child_lp; |
4de4c07c | 531 | |
3ced3da4 PA |
532 | child_lp = add_lwp (inferior_ptid); |
533 | child_lp->stopped = 1; | |
25289eb2 | 534 | child_lp->last_resume_kind = resume_stop; |
6c95b8df | 535 | |
6c95b8df | 536 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 537 | check_for_thread_db (); |
4de4c07c DJ |
538 | } |
539 | ||
540 | return 0; | |
541 | } | |
542 | ||
4de4c07c | 543 | \f |
77b06cd7 | 544 | static int |
a863b201 | 545 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 546 | { |
96d7229d | 547 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
548 | } |
549 | ||
eb73ad13 | 550 | static int |
973fc227 | 551 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
552 | { |
553 | return 0; | |
554 | } | |
555 | ||
77b06cd7 | 556 | static int |
3ecc7da0 | 557 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 558 | { |
96d7229d | 559 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
560 | } |
561 | ||
eb73ad13 | 562 | static int |
e98cf0cd | 563 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
564 | { |
565 | return 0; | |
566 | } | |
567 | ||
77b06cd7 | 568 | static int |
ba025e51 | 569 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 570 | { |
96d7229d | 571 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
572 | } |
573 | ||
eb73ad13 | 574 | static int |
758e29d2 | 575 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
576 | { |
577 | return 0; | |
578 | } | |
579 | ||
a96d9b2e | 580 | static int |
ff214e67 TT |
581 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
582 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
583 | int table_size, int *table) |
584 | { | |
96d7229d | 585 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
586 | return 1; |
587 | ||
a96d9b2e SDJ |
588 | /* On GNU/Linux, we ignore the arguments. It means that we only |
589 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 590 | |
a96d9b2e SDJ |
591 | Also, we do not use the `table' information because we do not |
592 | filter system calls here. We let GDB do the logic for us. */ | |
593 | return 0; | |
594 | } | |
595 | ||
d6b0e80f AC |
596 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
597 | are processes sharing the same VM space. A multi-threaded process | |
598 | is basically a group of such processes. However, such a grouping | |
599 | is almost entirely a user-space issue; the kernel doesn't enforce | |
600 | such a grouping at all (this might change in the future). In | |
601 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
602 | Threads library) to provide such a grouping. | |
603 | ||
604 | It is perfectly well possible to write a multi-threaded application | |
605 | without the assistance of a threads library, by using the clone | |
606 | system call directly. This module should be able to give some | |
607 | rudimentary support for debugging such applications if developers | |
608 | specify the CLONE_PTRACE flag in the clone system call, and are | |
609 | using the Linux kernel 2.4 or above. | |
610 | ||
611 | Note that there are some peculiarities in GNU/Linux that affect | |
612 | this code: | |
613 | ||
614 | - In general one should specify the __WCLONE flag to waitpid in | |
615 | order to make it report events for any of the cloned processes | |
616 | (and leave it out for the initial process). However, if a cloned | |
617 | process has exited the exit status is only reported if the | |
618 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
619 | we cannot use it since GDB must work on older systems too. | |
620 | ||
621 | - When a traced, cloned process exits and is waited for by the | |
622 | debugger, the kernel reassigns it to the original parent and | |
623 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
624 | library doesn't notice this, which leads to the "zombie problem": | |
625 | When debugged a multi-threaded process that spawns a lot of | |
626 | threads will run out of processes, even if the threads exit, | |
627 | because the "zombies" stay around. */ | |
628 | ||
629 | /* List of known LWPs. */ | |
9f0bdab8 | 630 | struct lwp_info *lwp_list; |
d6b0e80f AC |
631 | \f |
632 | ||
d6b0e80f AC |
633 | /* Original signal mask. */ |
634 | static sigset_t normal_mask; | |
635 | ||
636 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
637 | _initialize_linux_nat. */ | |
638 | static sigset_t suspend_mask; | |
639 | ||
7feb7d06 PA |
640 | /* Signals to block to make that sigsuspend work. */ |
641 | static sigset_t blocked_mask; | |
642 | ||
643 | /* SIGCHLD action. */ | |
644 | struct sigaction sigchld_action; | |
b84876c2 | 645 | |
7feb7d06 PA |
646 | /* Block child signals (SIGCHLD and linux threads signals), and store |
647 | the previous mask in PREV_MASK. */ | |
84e46146 | 648 | |
7feb7d06 PA |
649 | static void |
650 | block_child_signals (sigset_t *prev_mask) | |
651 | { | |
652 | /* Make sure SIGCHLD is blocked. */ | |
653 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
654 | sigaddset (&blocked_mask, SIGCHLD); | |
655 | ||
656 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
657 | } | |
658 | ||
659 | /* Restore child signals mask, previously returned by | |
660 | block_child_signals. */ | |
661 | ||
662 | static void | |
663 | restore_child_signals_mask (sigset_t *prev_mask) | |
664 | { | |
665 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
666 | } | |
2455069d UW |
667 | |
668 | /* Mask of signals to pass directly to the inferior. */ | |
669 | static sigset_t pass_mask; | |
670 | ||
671 | /* Update signals to pass to the inferior. */ | |
672 | static void | |
94bedb42 TT |
673 | linux_nat_pass_signals (struct target_ops *self, |
674 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
675 | { |
676 | int signo; | |
677 | ||
678 | sigemptyset (&pass_mask); | |
679 | ||
680 | for (signo = 1; signo < NSIG; signo++) | |
681 | { | |
2ea28649 | 682 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
683 | if (target_signo < numsigs && pass_signals[target_signo]) |
684 | sigaddset (&pass_mask, signo); | |
685 | } | |
686 | } | |
687 | ||
d6b0e80f AC |
688 | \f |
689 | ||
690 | /* Prototypes for local functions. */ | |
691 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 692 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 693 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
20ba1ce6 | 694 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, void *data); |
710151dd | 695 | |
d6b0e80f | 696 | \f |
d6b0e80f | 697 | |
7b50312a PA |
698 | /* Destroy and free LP. */ |
699 | ||
700 | static void | |
701 | lwp_free (struct lwp_info *lp) | |
702 | { | |
703 | xfree (lp->arch_private); | |
704 | xfree (lp); | |
705 | } | |
706 | ||
d90e17a7 PA |
707 | /* Remove all LWPs belong to PID from the lwp list. */ |
708 | ||
709 | static void | |
710 | purge_lwp_list (int pid) | |
711 | { | |
712 | struct lwp_info *lp, *lpprev, *lpnext; | |
713 | ||
714 | lpprev = NULL; | |
715 | ||
716 | for (lp = lwp_list; lp; lp = lpnext) | |
717 | { | |
718 | lpnext = lp->next; | |
719 | ||
720 | if (ptid_get_pid (lp->ptid) == pid) | |
721 | { | |
722 | if (lp == lwp_list) | |
723 | lwp_list = lp->next; | |
724 | else | |
725 | lpprev->next = lp->next; | |
726 | ||
7b50312a | 727 | lwp_free (lp); |
d90e17a7 PA |
728 | } |
729 | else | |
730 | lpprev = lp; | |
731 | } | |
732 | } | |
733 | ||
26cb8b7c PA |
734 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
735 | in the process. Return a pointer to the structure describing the | |
736 | new LWP. | |
737 | ||
738 | This differs from add_lwp in that we don't let the arch specific | |
739 | bits know about this new thread. Current clients of this callback | |
740 | take the opportunity to install watchpoints in the new thread, and | |
741 | we shouldn't do that for the first thread. If we're spawning a | |
742 | child ("run"), the thread executes the shell wrapper first, and we | |
743 | shouldn't touch it until it execs the program we want to debug. | |
744 | For "attach", it'd be okay to call the callback, but it's not | |
745 | necessary, because watchpoints can't yet have been inserted into | |
746 | the inferior. */ | |
d6b0e80f AC |
747 | |
748 | static struct lwp_info * | |
26cb8b7c | 749 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
750 | { |
751 | struct lwp_info *lp; | |
752 | ||
dfd4cc63 | 753 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
754 | |
755 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
756 | ||
757 | memset (lp, 0, sizeof (struct lwp_info)); | |
758 | ||
25289eb2 | 759 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
760 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
761 | ||
762 | lp->ptid = ptid; | |
dc146f7c | 763 | lp->core = -1; |
d6b0e80f AC |
764 | |
765 | lp->next = lwp_list; | |
766 | lwp_list = lp; | |
d6b0e80f | 767 | |
26cb8b7c PA |
768 | return lp; |
769 | } | |
770 | ||
771 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
772 | structure describing the new LWP. The LWP should already be | |
773 | stopped. */ | |
774 | ||
775 | static struct lwp_info * | |
776 | add_lwp (ptid_t ptid) | |
777 | { | |
778 | struct lwp_info *lp; | |
779 | ||
780 | lp = add_initial_lwp (ptid); | |
781 | ||
6e012a6c PA |
782 | /* Let the arch specific bits know about this new thread. Current |
783 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
784 | watchpoints in the new thread. We don't do this for the first |
785 | thread though. See add_initial_lwp. */ | |
786 | if (linux_nat_new_thread != NULL) | |
7b50312a | 787 | linux_nat_new_thread (lp); |
9f0bdab8 | 788 | |
d6b0e80f AC |
789 | return lp; |
790 | } | |
791 | ||
792 | /* Remove the LWP specified by PID from the list. */ | |
793 | ||
794 | static void | |
795 | delete_lwp (ptid_t ptid) | |
796 | { | |
797 | struct lwp_info *lp, *lpprev; | |
798 | ||
799 | lpprev = NULL; | |
800 | ||
801 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
802 | if (ptid_equal (lp->ptid, ptid)) | |
803 | break; | |
804 | ||
805 | if (!lp) | |
806 | return; | |
807 | ||
d6b0e80f AC |
808 | if (lpprev) |
809 | lpprev->next = lp->next; | |
810 | else | |
811 | lwp_list = lp->next; | |
812 | ||
7b50312a | 813 | lwp_free (lp); |
d6b0e80f AC |
814 | } |
815 | ||
816 | /* Return a pointer to the structure describing the LWP corresponding | |
817 | to PID. If no corresponding LWP could be found, return NULL. */ | |
818 | ||
819 | static struct lwp_info * | |
820 | find_lwp_pid (ptid_t ptid) | |
821 | { | |
822 | struct lwp_info *lp; | |
823 | int lwp; | |
824 | ||
dfd4cc63 LM |
825 | if (ptid_lwp_p (ptid)) |
826 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 827 | else |
dfd4cc63 | 828 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
829 | |
830 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 831 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
832 | return lp; |
833 | ||
834 | return NULL; | |
835 | } | |
836 | ||
837 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
838 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
839 | pointer to the structure describing that LWP immediately. | |
840 | Otherwise return NULL. */ | |
841 | ||
842 | struct lwp_info * | |
d90e17a7 PA |
843 | iterate_over_lwps (ptid_t filter, |
844 | int (*callback) (struct lwp_info *, void *), | |
845 | void *data) | |
d6b0e80f AC |
846 | { |
847 | struct lwp_info *lp, *lpnext; | |
848 | ||
849 | for (lp = lwp_list; lp; lp = lpnext) | |
850 | { | |
851 | lpnext = lp->next; | |
d90e17a7 PA |
852 | |
853 | if (ptid_match (lp->ptid, filter)) | |
854 | { | |
855 | if ((*callback) (lp, data)) | |
856 | return lp; | |
857 | } | |
d6b0e80f AC |
858 | } |
859 | ||
860 | return NULL; | |
861 | } | |
862 | ||
2277426b PA |
863 | /* Update our internal state when changing from one checkpoint to |
864 | another indicated by NEW_PTID. We can only switch single-threaded | |
865 | applications, so we only create one new LWP, and the previous list | |
866 | is discarded. */ | |
f973ed9c DJ |
867 | |
868 | void | |
869 | linux_nat_switch_fork (ptid_t new_ptid) | |
870 | { | |
871 | struct lwp_info *lp; | |
872 | ||
dfd4cc63 | 873 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 874 | |
f973ed9c DJ |
875 | lp = add_lwp (new_ptid); |
876 | lp->stopped = 1; | |
e26af52f | 877 | |
2277426b PA |
878 | /* This changes the thread's ptid while preserving the gdb thread |
879 | num. Also changes the inferior pid, while preserving the | |
880 | inferior num. */ | |
881 | thread_change_ptid (inferior_ptid, new_ptid); | |
882 | ||
883 | /* We've just told GDB core that the thread changed target id, but, | |
884 | in fact, it really is a different thread, with different register | |
885 | contents. */ | |
886 | registers_changed (); | |
e26af52f DJ |
887 | } |
888 | ||
e26af52f DJ |
889 | /* Handle the exit of a single thread LP. */ |
890 | ||
891 | static void | |
892 | exit_lwp (struct lwp_info *lp) | |
893 | { | |
e09875d4 | 894 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
895 | |
896 | if (th) | |
e26af52f | 897 | { |
17faa917 DJ |
898 | if (print_thread_events) |
899 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
900 | ||
4f8d22e3 | 901 | delete_thread (lp->ptid); |
e26af52f DJ |
902 | } |
903 | ||
904 | delete_lwp (lp->ptid); | |
905 | } | |
906 | ||
a0ef4274 DJ |
907 | /* Wait for the LWP specified by LP, which we have just attached to. |
908 | Returns a wait status for that LWP, to cache. */ | |
909 | ||
910 | static int | |
911 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
912 | int *signalled) | |
913 | { | |
dfd4cc63 | 914 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
915 | int status; |
916 | ||
644cebc9 | 917 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
918 | { |
919 | if (debug_linux_nat) | |
920 | fprintf_unfiltered (gdb_stdlog, | |
921 | "LNPAW: Attaching to a stopped process\n"); | |
922 | ||
923 | /* The process is definitely stopped. It is in a job control | |
924 | stop, unless the kernel predates the TASK_STOPPED / | |
925 | TASK_TRACED distinction, in which case it might be in a | |
926 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
927 | can kill it, signal it, et cetera. | |
928 | ||
929 | First make sure there is a pending SIGSTOP. Since we are | |
930 | already attached, the process can not transition from stopped | |
931 | to running without a PTRACE_CONT; so we know this signal will | |
932 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
933 | probably already in the queue (unless this kernel is old | |
934 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
935 | is not an RT signal, it can only be queued once. */ | |
936 | kill_lwp (pid, SIGSTOP); | |
937 | ||
938 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
939 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
940 | ptrace (PTRACE_CONT, pid, 0, 0); | |
941 | } | |
942 | ||
943 | /* Make sure the initial process is stopped. The user-level threads | |
944 | layer might want to poke around in the inferior, and that won't | |
945 | work if things haven't stabilized yet. */ | |
946 | new_pid = my_waitpid (pid, &status, 0); | |
947 | if (new_pid == -1 && errno == ECHILD) | |
948 | { | |
949 | if (first) | |
950 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
951 | ||
952 | /* Try again with __WCLONE to check cloned processes. */ | |
953 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
954 | *cloned = 1; | |
955 | } | |
956 | ||
dacc9cb2 PP |
957 | gdb_assert (pid == new_pid); |
958 | ||
959 | if (!WIFSTOPPED (status)) | |
960 | { | |
961 | /* The pid we tried to attach has apparently just exited. */ | |
962 | if (debug_linux_nat) | |
963 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
964 | pid, status_to_str (status)); | |
965 | return status; | |
966 | } | |
a0ef4274 DJ |
967 | |
968 | if (WSTOPSIG (status) != SIGSTOP) | |
969 | { | |
970 | *signalled = 1; | |
971 | if (debug_linux_nat) | |
972 | fprintf_unfiltered (gdb_stdlog, | |
973 | "LNPAW: Received %s after attaching\n", | |
974 | status_to_str (status)); | |
975 | } | |
976 | ||
977 | return status; | |
978 | } | |
979 | ||
84636d28 PA |
980 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
981 | the new LWP could not be attached, or 1 if we're already auto | |
982 | attached to this thread, but haven't processed the | |
983 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
984 | its existance, without considering it an error. */ | |
d6b0e80f | 985 | |
9ee57c33 | 986 | int |
93815fbf | 987 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 988 | { |
9ee57c33 | 989 | struct lwp_info *lp; |
84636d28 | 990 | int lwpid; |
d6b0e80f | 991 | |
dfd4cc63 | 992 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 993 | |
9ee57c33 | 994 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 995 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f | 996 | |
3b27ef47 | 997 | /* We assume that we're already attached to any LWP that is already |
d6b0e80f AC |
998 | in our list of LWPs. If we're not seeing exit events from threads |
999 | and we've had PID wraparound since we last tried to stop all threads, | |
1000 | this assumption might be wrong; fortunately, this is very unlikely | |
1001 | to happen. */ | |
3b27ef47 | 1002 | if (lp == NULL) |
d6b0e80f | 1003 | { |
a0ef4274 | 1004 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1005 | |
84636d28 | 1006 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1007 | { |
96d7229d | 1008 | if (linux_supports_tracefork ()) |
84636d28 PA |
1009 | { |
1010 | /* If we haven't stopped all threads when we get here, | |
1011 | we may have seen a thread listed in thread_db's list, | |
1012 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1013 | that's the case, ignore this new thread, and let | |
1014 | normal event handling discover it later. */ | |
1015 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1016 | { | |
1017 | /* We've already seen this thread stop, but we | |
1018 | haven't seen the PTRACE_EVENT_CLONE extended | |
1019 | event yet. */ | |
3b27ef47 PA |
1020 | if (debug_linux_nat) |
1021 | fprintf_unfiltered (gdb_stdlog, | |
1022 | "LLAL: attach failed, but already seen " | |
1023 | "this thread %s stop\n", | |
1024 | target_pid_to_str (ptid)); | |
1025 | return 1; | |
84636d28 PA |
1026 | } |
1027 | else | |
1028 | { | |
1029 | int new_pid; | |
1030 | int status; | |
1031 | ||
3b27ef47 PA |
1032 | if (debug_linux_nat) |
1033 | fprintf_unfiltered (gdb_stdlog, | |
1034 | "LLAL: attach failed, and haven't seen " | |
1035 | "this thread %s stop yet\n", | |
1036 | target_pid_to_str (ptid)); | |
1037 | ||
1038 | /* We may or may not be attached to the LWP already. | |
1039 | Try waitpid on it. If that errors, we're not | |
1040 | attached to the LWP yet. Otherwise, we're | |
1041 | already attached. */ | |
a33e3959 | 1042 | gdb_assert (lwpid > 0); |
84636d28 PA |
1043 | new_pid = my_waitpid (lwpid, &status, WNOHANG); |
1044 | if (new_pid == -1 && errno == ECHILD) | |
1045 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1046 | if (new_pid != -1) | |
1047 | { | |
3b27ef47 PA |
1048 | if (new_pid == 0) |
1049 | { | |
1050 | /* The child hasn't stopped for its initial | |
1051 | SIGSTOP stop yet. */ | |
1052 | if (debug_linux_nat) | |
1053 | fprintf_unfiltered (gdb_stdlog, | |
1054 | "LLAL: child hasn't " | |
1055 | "stopped yet\n"); | |
1056 | } | |
1057 | else if (WIFSTOPPED (status)) | |
1058 | { | |
1059 | if (debug_linux_nat) | |
1060 | fprintf_unfiltered (gdb_stdlog, | |
1061 | "LLAL: adding to stopped_pids\n"); | |
1062 | add_to_pid_list (&stopped_pids, lwpid, status); | |
1063 | } | |
84636d28 PA |
1064 | return 1; |
1065 | } | |
1066 | } | |
1067 | } | |
1068 | ||
9ee57c33 DJ |
1069 | /* If we fail to attach to the thread, issue a warning, |
1070 | but continue. One way this can happen is if thread | |
e9efe249 | 1071 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1072 | bug may place threads in the thread list and then fail |
1073 | to create them. */ | |
1074 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1075 | safe_strerror (errno)); | |
1076 | return -1; | |
1077 | } | |
1078 | ||
d6b0e80f AC |
1079 | if (debug_linux_nat) |
1080 | fprintf_unfiltered (gdb_stdlog, | |
1081 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1082 | target_pid_to_str (ptid)); | |
1083 | ||
a0ef4274 | 1084 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1085 | if (!WIFSTOPPED (status)) |
12696c10 | 1086 | return 1; |
dacc9cb2 | 1087 | |
a0ef4274 DJ |
1088 | lp = add_lwp (ptid); |
1089 | lp->stopped = 1; | |
3b27ef47 | 1090 | lp->last_resume_kind = resume_stop; |
a0ef4274 DJ |
1091 | lp->cloned = cloned; |
1092 | lp->signalled = signalled; | |
1093 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1094 | { |
a0ef4274 DJ |
1095 | lp->resumed = 1; |
1096 | lp->status = status; | |
d6b0e80f AC |
1097 | } |
1098 | ||
dfd4cc63 | 1099 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1100 | |
1101 | if (debug_linux_nat) | |
1102 | { | |
1103 | fprintf_unfiltered (gdb_stdlog, | |
1104 | "LLAL: waitpid %s received %s\n", | |
1105 | target_pid_to_str (ptid), | |
1106 | status_to_str (status)); | |
1107 | } | |
1108 | } | |
9ee57c33 | 1109 | |
9ee57c33 | 1110 | return 0; |
d6b0e80f AC |
1111 | } |
1112 | ||
b84876c2 | 1113 | static void |
136d6dae VP |
1114 | linux_nat_create_inferior (struct target_ops *ops, |
1115 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1116 | int from_tty) |
1117 | { | |
8cc73a39 SDJ |
1118 | struct cleanup *restore_personality |
1119 | = maybe_disable_address_space_randomization (disable_randomization); | |
b84876c2 PA |
1120 | |
1121 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1122 | we have to mask the async mode. */ | |
1123 | ||
2455069d | 1124 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1125 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1126 | |
136d6dae | 1127 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1128 | |
8cc73a39 | 1129 | do_cleanups (restore_personality); |
b84876c2 PA |
1130 | } |
1131 | ||
8784d563 PA |
1132 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not |
1133 | already attached. Returns true if a new LWP is found, false | |
1134 | otherwise. */ | |
1135 | ||
1136 | static int | |
1137 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1138 | { | |
1139 | struct lwp_info *lp; | |
1140 | ||
1141 | /* Ignore LWPs we're already attached to. */ | |
1142 | lp = find_lwp_pid (ptid); | |
1143 | if (lp == NULL) | |
1144 | { | |
1145 | int lwpid = ptid_get_lwp (ptid); | |
1146 | ||
1147 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) | |
1148 | { | |
1149 | int err = errno; | |
1150 | ||
1151 | /* Be quiet if we simply raced with the thread exiting. | |
1152 | EPERM is returned if the thread's task still exists, and | |
1153 | is marked as exited or zombie, as well as other | |
1154 | conditions, so in that case, confirm the status in | |
1155 | /proc/PID/status. */ | |
1156 | if (err == ESRCH | |
1157 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1158 | { | |
1159 | if (debug_linux_nat) | |
1160 | { | |
1161 | fprintf_unfiltered (gdb_stdlog, | |
1162 | "Cannot attach to lwp %d: " | |
1163 | "thread is gone (%d: %s)\n", | |
1164 | lwpid, err, safe_strerror (err)); | |
1165 | } | |
1166 | } | |
1167 | else | |
1168 | { | |
f71f0b0d | 1169 | warning (_("Cannot attach to lwp %d: %s"), |
8784d563 PA |
1170 | lwpid, |
1171 | linux_ptrace_attach_fail_reason_string (ptid, | |
1172 | err)); | |
1173 | } | |
1174 | } | |
1175 | else | |
1176 | { | |
1177 | if (debug_linux_nat) | |
1178 | fprintf_unfiltered (gdb_stdlog, | |
1179 | "PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1180 | target_pid_to_str (ptid)); | |
1181 | ||
1182 | lp = add_lwp (ptid); | |
1183 | lp->cloned = 1; | |
1184 | ||
1185 | /* The next time we wait for this LWP we'll see a SIGSTOP as | |
1186 | PTRACE_ATTACH brings it to a halt. */ | |
1187 | lp->signalled = 1; | |
1188 | ||
1189 | /* We need to wait for a stop before being able to make the | |
1190 | next ptrace call on this LWP. */ | |
1191 | lp->must_set_ptrace_flags = 1; | |
1192 | } | |
1193 | ||
1194 | return 1; | |
1195 | } | |
1196 | return 0; | |
1197 | } | |
1198 | ||
d6b0e80f | 1199 | static void |
c0939df1 | 1200 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1201 | { |
1202 | struct lwp_info *lp; | |
d6b0e80f | 1203 | int status; |
af990527 | 1204 | ptid_t ptid; |
d6b0e80f | 1205 | |
2455069d | 1206 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1207 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1208 | |
492d29ea | 1209 | TRY |
87b0bb13 JK |
1210 | { |
1211 | linux_ops->to_attach (ops, args, from_tty); | |
1212 | } | |
492d29ea | 1213 | CATCH (ex, RETURN_MASK_ERROR) |
87b0bb13 JK |
1214 | { |
1215 | pid_t pid = parse_pid_to_attach (args); | |
1216 | struct buffer buffer; | |
1217 | char *message, *buffer_s; | |
1218 | ||
1219 | message = xstrdup (ex.message); | |
1220 | make_cleanup (xfree, message); | |
1221 | ||
1222 | buffer_init (&buffer); | |
7ae1a6a6 | 1223 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1224 | |
1225 | buffer_grow_str0 (&buffer, ""); | |
1226 | buffer_s = buffer_finish (&buffer); | |
1227 | make_cleanup (xfree, buffer_s); | |
1228 | ||
7ae1a6a6 PA |
1229 | if (*buffer_s != '\0') |
1230 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1231 | else | |
1232 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1233 | } |
492d29ea | 1234 | END_CATCH |
d6b0e80f | 1235 | |
af990527 PA |
1236 | /* The ptrace base target adds the main thread with (pid,0,0) |
1237 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1238 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1239 | ptid_get_pid (inferior_ptid), | |
1240 | 0); | |
af990527 PA |
1241 | thread_change_ptid (inferior_ptid, ptid); |
1242 | ||
9f0bdab8 | 1243 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1244 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1245 | |
1246 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1247 | &lp->signalled); | |
dacc9cb2 PP |
1248 | if (!WIFSTOPPED (status)) |
1249 | { | |
1250 | if (WIFEXITED (status)) | |
1251 | { | |
1252 | int exit_code = WEXITSTATUS (status); | |
1253 | ||
1254 | target_terminal_ours (); | |
1255 | target_mourn_inferior (); | |
1256 | if (exit_code == 0) | |
1257 | error (_("Unable to attach: program exited normally.")); | |
1258 | else | |
1259 | error (_("Unable to attach: program exited with code %d."), | |
1260 | exit_code); | |
1261 | } | |
1262 | else if (WIFSIGNALED (status)) | |
1263 | { | |
2ea28649 | 1264 | enum gdb_signal signo; |
dacc9cb2 PP |
1265 | |
1266 | target_terminal_ours (); | |
1267 | target_mourn_inferior (); | |
1268 | ||
2ea28649 | 1269 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1270 | error (_("Unable to attach: program terminated with signal " |
1271 | "%s, %s."), | |
2ea28649 PA |
1272 | gdb_signal_to_name (signo), |
1273 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1274 | } |
1275 | ||
1276 | internal_error (__FILE__, __LINE__, | |
1277 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1278 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1279 | } |
1280 | ||
a0ef4274 | 1281 | lp->stopped = 1; |
9f0bdab8 | 1282 | |
a0ef4274 | 1283 | /* Save the wait status to report later. */ |
d6b0e80f | 1284 | lp->resumed = 1; |
a0ef4274 DJ |
1285 | if (debug_linux_nat) |
1286 | fprintf_unfiltered (gdb_stdlog, | |
1287 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1288 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1289 | |
7feb7d06 PA |
1290 | lp->status = status; |
1291 | ||
8784d563 PA |
1292 | /* We must attach to every LWP. If /proc is mounted, use that to |
1293 | find them now. The inferior may be using raw clone instead of | |
1294 | using pthreads. But even if it is using pthreads, thread_db | |
1295 | walks structures in the inferior's address space to find the list | |
1296 | of threads/LWPs, and those structures may well be corrupted. | |
1297 | Note that once thread_db is loaded, we'll still use it to list | |
1298 | threads and associate pthread info with each LWP. */ | |
1299 | linux_proc_attach_tgid_threads (ptid_get_pid (lp->ptid), | |
1300 | attach_proc_task_lwp_callback); | |
1301 | ||
7feb7d06 PA |
1302 | if (target_can_async_p ()) |
1303 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1304 | } |
1305 | ||
a0ef4274 DJ |
1306 | /* Get pending status of LP. */ |
1307 | static int | |
1308 | get_pending_status (struct lwp_info *lp, int *status) | |
1309 | { | |
a493e3e2 | 1310 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1311 | |
1312 | /* If we paused threads momentarily, we may have stored pending | |
1313 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1314 | and GDB core hasn't seen any signal for those threads. | |
1315 | Otherwise, the last signal reported to the core is found in the | |
1316 | thread object's stop_signal. | |
1317 | ||
1318 | There's a corner case that isn't handled here at present. Only | |
1319 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1320 | stop_signal make sense as a real signal to pass to the inferior. | |
1321 | Some catchpoint related events, like | |
1322 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1323 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1324 | those traps are debug API (ptrace in our case) related and |
1325 | induced; the inferior wouldn't see them if it wasn't being | |
1326 | traced. Hence, we should never pass them to the inferior, even | |
1327 | when set to pass state. Since this corner case isn't handled by | |
1328 | infrun.c when proceeding with a signal, for consistency, neither | |
1329 | do we handle it here (or elsewhere in the file we check for | |
1330 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1331 | this is really a corner case. */ | |
1332 | ||
1333 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1334 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1335 | else if (lp->status) |
2ea28649 | 1336 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1337 | else if (non_stop && !is_executing (lp->ptid)) |
1338 | { | |
1339 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1340 | |
16c381f0 | 1341 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1342 | } |
1343 | else if (!non_stop) | |
a0ef4274 | 1344 | { |
ca2163eb PA |
1345 | struct target_waitstatus last; |
1346 | ptid_t last_ptid; | |
4c28f408 | 1347 | |
ca2163eb | 1348 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1349 | |
dfd4cc63 | 1350 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1351 | { |
e09875d4 | 1352 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1353 | |
16c381f0 | 1354 | signo = tp->suspend.stop_signal; |
4c28f408 | 1355 | } |
ca2163eb | 1356 | } |
4c28f408 | 1357 | |
ca2163eb | 1358 | *status = 0; |
4c28f408 | 1359 | |
a493e3e2 | 1360 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1361 | { |
1362 | if (debug_linux_nat) | |
1363 | fprintf_unfiltered (gdb_stdlog, | |
1364 | "GPT: lwp %s has no pending signal\n", | |
1365 | target_pid_to_str (lp->ptid)); | |
1366 | } | |
1367 | else if (!signal_pass_state (signo)) | |
1368 | { | |
1369 | if (debug_linux_nat) | |
3e43a32a MS |
1370 | fprintf_unfiltered (gdb_stdlog, |
1371 | "GPT: lwp %s had signal %s, " | |
1372 | "but it is in no pass state\n", | |
ca2163eb | 1373 | target_pid_to_str (lp->ptid), |
2ea28649 | 1374 | gdb_signal_to_string (signo)); |
a0ef4274 | 1375 | } |
a0ef4274 | 1376 | else |
4c28f408 | 1377 | { |
2ea28649 | 1378 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1379 | |
1380 | if (debug_linux_nat) | |
1381 | fprintf_unfiltered (gdb_stdlog, | |
1382 | "GPT: lwp %s has pending signal %s\n", | |
1383 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1384 | gdb_signal_to_string (signo)); |
4c28f408 | 1385 | } |
a0ef4274 DJ |
1386 | |
1387 | return 0; | |
1388 | } | |
1389 | ||
d6b0e80f AC |
1390 | static int |
1391 | detach_callback (struct lwp_info *lp, void *data) | |
1392 | { | |
1393 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1394 | ||
1395 | if (debug_linux_nat && lp->status) | |
1396 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1397 | strsignal (WSTOPSIG (lp->status)), | |
1398 | target_pid_to_str (lp->ptid)); | |
1399 | ||
a0ef4274 DJ |
1400 | /* If there is a pending SIGSTOP, get rid of it. */ |
1401 | if (lp->signalled) | |
d6b0e80f | 1402 | { |
d6b0e80f AC |
1403 | if (debug_linux_nat) |
1404 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1405 | "DC: Sending SIGCONT to %s\n", |
1406 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1407 | |
dfd4cc63 | 1408 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1409 | lp->signalled = 0; |
d6b0e80f AC |
1410 | } |
1411 | ||
1412 | /* We don't actually detach from the LWP that has an id equal to the | |
1413 | overall process id just yet. */ | |
dfd4cc63 | 1414 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1415 | { |
a0ef4274 DJ |
1416 | int status = 0; |
1417 | ||
1418 | /* Pass on any pending signal for this LWP. */ | |
1419 | get_pending_status (lp, &status); | |
1420 | ||
7b50312a PA |
1421 | if (linux_nat_prepare_to_resume != NULL) |
1422 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1423 | errno = 0; |
dfd4cc63 | 1424 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1425 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1426 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1427 | safe_strerror (errno)); |
1428 | ||
1429 | if (debug_linux_nat) | |
1430 | fprintf_unfiltered (gdb_stdlog, | |
1431 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1432 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1433 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1434 | |
1435 | delete_lwp (lp->ptid); | |
1436 | } | |
1437 | ||
1438 | return 0; | |
1439 | } | |
1440 | ||
1441 | static void | |
52554a0e | 1442 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1443 | { |
b84876c2 | 1444 | int pid; |
a0ef4274 | 1445 | int status; |
d90e17a7 PA |
1446 | struct lwp_info *main_lwp; |
1447 | ||
dfd4cc63 | 1448 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1449 | |
ae5e0686 MK |
1450 | /* Don't unregister from the event loop, as there may be other |
1451 | inferiors running. */ | |
b84876c2 | 1452 | |
4c28f408 PA |
1453 | /* Stop all threads before detaching. ptrace requires that the |
1454 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1455 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1456 | /* ... and wait until all of them have reported back that |
1457 | they're no longer running. */ | |
d90e17a7 | 1458 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1459 | |
d90e17a7 | 1460 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1461 | |
1462 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1463 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1464 | |
1465 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1466 | |
a0ef4274 DJ |
1467 | /* Pass on any pending signal for the last LWP. */ |
1468 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1469 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1470 | && WIFSTOPPED (status)) |
1471 | { | |
52554a0e TT |
1472 | char *tem; |
1473 | ||
a0ef4274 DJ |
1474 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1475 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1476 | tem = alloca (8); |
cde33bf1 | 1477 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1478 | args = tem; |
ddabfc73 TT |
1479 | if (debug_linux_nat) |
1480 | fprintf_unfiltered (gdb_stdlog, | |
1481 | "LND: Sending signal %s to %s\n", | |
1482 | args, | |
1483 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1484 | } |
1485 | ||
7b50312a PA |
1486 | if (linux_nat_prepare_to_resume != NULL) |
1487 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1488 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1489 | |
7a7d3353 PA |
1490 | if (forks_exist_p ()) |
1491 | { | |
1492 | /* Multi-fork case. The current inferior_ptid is being detached | |
1493 | from, but there are other viable forks to debug. Detach from | |
1494 | the current fork, and context-switch to the first | |
1495 | available. */ | |
1496 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1497 | } |
1498 | else | |
1499 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1500 | } |
1501 | ||
8a99810d PA |
1502 | /* Resume execution of the inferior process. If STEP is nonzero, |
1503 | single-step it. If SIGNAL is nonzero, give it that signal. */ | |
1504 | ||
1505 | static void | |
23f238d3 PA |
1506 | linux_resume_one_lwp_throw (struct lwp_info *lp, int step, |
1507 | enum gdb_signal signo) | |
8a99810d | 1508 | { |
8a99810d | 1509 | lp->step = step; |
9c02b525 PA |
1510 | |
1511 | /* stop_pc doubles as the PC the LWP had when it was last resumed. | |
1512 | We only presently need that if the LWP is stepped though (to | |
1513 | handle the case of stepping a breakpoint instruction). */ | |
1514 | if (step) | |
1515 | { | |
1516 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
1517 | ||
1518 | lp->stop_pc = regcache_read_pc (regcache); | |
1519 | } | |
1520 | else | |
1521 | lp->stop_pc = 0; | |
1522 | ||
8a99810d PA |
1523 | if (linux_nat_prepare_to_resume != NULL) |
1524 | linux_nat_prepare_to_resume (lp); | |
90ad5e1d | 1525 | linux_ops->to_resume (linux_ops, lp->ptid, step, signo); |
23f238d3 PA |
1526 | |
1527 | /* Successfully resumed. Clear state that no longer makes sense, | |
1528 | and mark the LWP as running. Must not do this before resuming | |
1529 | otherwise if that fails other code will be confused. E.g., we'd | |
1530 | later try to stop the LWP and hang forever waiting for a stop | |
1531 | status. Note that we must not throw after this is cleared, | |
1532 | otherwise handle_zombie_lwp_error would get confused. */ | |
8a99810d | 1533 | lp->stopped = 0; |
23f238d3 | 1534 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; |
8a99810d PA |
1535 | registers_changed_ptid (lp->ptid); |
1536 | } | |
1537 | ||
23f238d3 PA |
1538 | /* Called when we try to resume a stopped LWP and that errors out. If |
1539 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
1540 | or about to become), discard the error, clear any pending status | |
1541 | the LWP may have, and return true (we'll collect the exit status | |
1542 | soon enough). Otherwise, return false. */ | |
1543 | ||
1544 | static int | |
1545 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
1546 | { | |
1547 | /* If we get an error after resuming the LWP successfully, we'd | |
1548 | confuse !T state for the LWP being gone. */ | |
1549 | gdb_assert (lp->stopped); | |
1550 | ||
1551 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
1552 | because even if ptrace failed with ESRCH, the tracee may be "not | |
1553 | yet fully dead", but already refusing ptrace requests. In that | |
1554 | case the tracee has 'R (Running)' state for a little bit | |
1555 | (observed in Linux 3.18). See also the note on ESRCH in the | |
1556 | ptrace(2) man page. Instead, check whether the LWP has any state | |
1557 | other than ptrace-stopped. */ | |
1558 | ||
1559 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
1560 | if (linux_proc_pid_is_trace_stopped_nowarn (ptid_get_lwp (lp->ptid)) == 0) | |
1561 | { | |
1562 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
1563 | lp->status = 0; | |
1564 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
1565 | return 1; | |
1566 | } | |
1567 | return 0; | |
1568 | } | |
1569 | ||
1570 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
1571 | disappears while we try to resume it. */ | |
1572 | ||
1573 | static void | |
1574 | linux_resume_one_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) | |
1575 | { | |
1576 | TRY | |
1577 | { | |
1578 | linux_resume_one_lwp_throw (lp, step, signo); | |
1579 | } | |
1580 | CATCH (ex, RETURN_MASK_ERROR) | |
1581 | { | |
1582 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
1583 | throw_exception (ex); | |
1584 | } | |
1585 | END_CATCH | |
1586 | } | |
1587 | ||
d6b0e80f AC |
1588 | /* Resume LP. */ |
1589 | ||
25289eb2 | 1590 | static void |
e5ef252a | 1591 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1592 | { |
25289eb2 | 1593 | if (lp->stopped) |
6c95b8df | 1594 | { |
c9657e70 | 1595 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
25289eb2 PA |
1596 | |
1597 | if (inf->vfork_child != NULL) | |
1598 | { | |
1599 | if (debug_linux_nat) | |
1600 | fprintf_unfiltered (gdb_stdlog, | |
1601 | "RC: Not resuming %s (vfork parent)\n", | |
1602 | target_pid_to_str (lp->ptid)); | |
1603 | } | |
8a99810d | 1604 | else if (!lwp_status_pending_p (lp)) |
25289eb2 PA |
1605 | { |
1606 | if (debug_linux_nat) | |
1607 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1608 | "RC: Resuming sibling %s, %s, %s\n", |
1609 | target_pid_to_str (lp->ptid), | |
1610 | (signo != GDB_SIGNAL_0 | |
1611 | ? strsignal (gdb_signal_to_host (signo)) | |
1612 | : "0"), | |
1613 | step ? "step" : "resume"); | |
25289eb2 | 1614 | |
8a99810d | 1615 | linux_resume_one_lwp (lp, step, signo); |
25289eb2 PA |
1616 | } |
1617 | else | |
1618 | { | |
1619 | if (debug_linux_nat) | |
1620 | fprintf_unfiltered (gdb_stdlog, | |
1621 | "RC: Not resuming sibling %s (has pending)\n", | |
1622 | target_pid_to_str (lp->ptid)); | |
1623 | } | |
6c95b8df | 1624 | } |
25289eb2 | 1625 | else |
d6b0e80f | 1626 | { |
d90e17a7 PA |
1627 | if (debug_linux_nat) |
1628 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1629 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1630 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1631 | } |
25289eb2 | 1632 | } |
d6b0e80f | 1633 | |
8817a6f2 PA |
1634 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1635 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1636 | |
25289eb2 | 1637 | static int |
8817a6f2 | 1638 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1639 | { |
e5ef252a PA |
1640 | enum gdb_signal signo = GDB_SIGNAL_0; |
1641 | ||
8817a6f2 PA |
1642 | if (lp == except) |
1643 | return 0; | |
1644 | ||
e5ef252a PA |
1645 | if (lp->stopped) |
1646 | { | |
1647 | struct thread_info *thread; | |
1648 | ||
1649 | thread = find_thread_ptid (lp->ptid); | |
1650 | if (thread != NULL) | |
1651 | { | |
70509625 | 1652 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1653 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1654 | } | |
1655 | } | |
1656 | ||
1657 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1658 | return 0; |
1659 | } | |
1660 | ||
1661 | static int | |
1662 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1663 | { | |
1664 | lp->resumed = 0; | |
25289eb2 | 1665 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1666 | return 0; |
1667 | } | |
1668 | ||
1669 | static int | |
1670 | resume_set_callback (struct lwp_info *lp, void *data) | |
1671 | { | |
1672 | lp->resumed = 1; | |
25289eb2 | 1673 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1674 | return 0; |
1675 | } | |
1676 | ||
1677 | static void | |
28439f5e | 1678 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1679 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1680 | { |
1681 | struct lwp_info *lp; | |
d90e17a7 | 1682 | int resume_many; |
d6b0e80f | 1683 | |
76f50ad1 DJ |
1684 | if (debug_linux_nat) |
1685 | fprintf_unfiltered (gdb_stdlog, | |
1686 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1687 | step ? "step" : "resume", | |
1688 | target_pid_to_str (ptid), | |
a493e3e2 | 1689 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1690 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1691 | target_pid_to_str (inferior_ptid)); |
1692 | ||
d6b0e80f | 1693 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1694 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1695 | || ptid_is_pid (ptid)); | |
4c28f408 | 1696 | |
e3e9f5a2 PA |
1697 | /* Mark the lwps we're resuming as resumed. */ |
1698 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1699 | |
d90e17a7 PA |
1700 | /* See if it's the current inferior that should be handled |
1701 | specially. */ | |
1702 | if (resume_many) | |
1703 | lp = find_lwp_pid (inferior_ptid); | |
1704 | else | |
1705 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1706 | gdb_assert (lp != NULL); |
d6b0e80f | 1707 | |
9f0bdab8 | 1708 | /* Remember if we're stepping. */ |
25289eb2 | 1709 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1710 | |
9f0bdab8 DJ |
1711 | /* If we have a pending wait status for this thread, there is no |
1712 | point in resuming the process. But first make sure that | |
1713 | linux_nat_wait won't preemptively handle the event - we | |
1714 | should never take this short-circuit if we are going to | |
1715 | leave LP running, since we have skipped resuming all the | |
1716 | other threads. This bit of code needs to be synchronized | |
1717 | with linux_nat_wait. */ | |
76f50ad1 | 1718 | |
9f0bdab8 DJ |
1719 | if (lp->status && WIFSTOPPED (lp->status)) |
1720 | { | |
2455069d UW |
1721 | if (!lp->step |
1722 | && WSTOPSIG (lp->status) | |
1723 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1724 | { |
9f0bdab8 DJ |
1725 | if (debug_linux_nat) |
1726 | fprintf_unfiltered (gdb_stdlog, | |
1727 | "LLR: Not short circuiting for ignored " | |
1728 | "status 0x%x\n", lp->status); | |
1729 | ||
d6b0e80f AC |
1730 | /* FIXME: What should we do if we are supposed to continue |
1731 | this thread with a signal? */ | |
a493e3e2 | 1732 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1733 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1734 | lp->status = 0; |
1735 | } | |
1736 | } | |
76f50ad1 | 1737 | |
8a99810d | 1738 | if (lwp_status_pending_p (lp)) |
9f0bdab8 DJ |
1739 | { |
1740 | /* FIXME: What should we do if we are supposed to continue | |
1741 | this thread with a signal? */ | |
a493e3e2 | 1742 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1743 | |
9f0bdab8 DJ |
1744 | if (debug_linux_nat) |
1745 | fprintf_unfiltered (gdb_stdlog, | |
1746 | "LLR: Short circuiting for status 0x%x\n", | |
1747 | lp->status); | |
d6b0e80f | 1748 | |
7feb7d06 PA |
1749 | if (target_can_async_p ()) |
1750 | { | |
1751 | target_async (inferior_event_handler, 0); | |
1752 | /* Tell the event loop we have something to process. */ | |
1753 | async_file_mark (); | |
1754 | } | |
9f0bdab8 | 1755 | return; |
d6b0e80f AC |
1756 | } |
1757 | ||
d90e17a7 | 1758 | if (resume_many) |
8817a6f2 | 1759 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 | 1760 | |
8a99810d | 1761 | linux_resume_one_lwp (lp, step, signo); |
9f0bdab8 | 1762 | |
d6b0e80f AC |
1763 | if (debug_linux_nat) |
1764 | fprintf_unfiltered (gdb_stdlog, | |
1765 | "LLR: %s %s, %s (resume event thread)\n", | |
1766 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1767 | target_pid_to_str (ptid), | |
a493e3e2 | 1768 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1769 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1770 | |
1771 | if (target_can_async_p ()) | |
8ea051c5 | 1772 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1773 | } |
1774 | ||
c5f62d5f | 1775 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1776 | |
1777 | static int | |
1778 | kill_lwp (int lwpid, int signo) | |
1779 | { | |
c5f62d5f DE |
1780 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1781 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1782 | |
1783 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1784 | { |
1785 | static int tkill_failed; | |
1786 | ||
1787 | if (!tkill_failed) | |
1788 | { | |
1789 | int ret; | |
1790 | ||
1791 | errno = 0; | |
1792 | ret = syscall (__NR_tkill, lwpid, signo); | |
1793 | if (errno != ENOSYS) | |
1794 | return ret; | |
1795 | tkill_failed = 1; | |
1796 | } | |
1797 | } | |
d6b0e80f AC |
1798 | #endif |
1799 | ||
1800 | return kill (lwpid, signo); | |
1801 | } | |
1802 | ||
ca2163eb PA |
1803 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1804 | event, check if the core is interested in it: if not, ignore the | |
1805 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1806 | syscall entry/exit status, since the ptrace event itself doesn't | |
1807 | indicate it, and report the trap to higher layers. */ | |
1808 | ||
1809 | static int | |
1810 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1811 | { | |
1812 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1813 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1814 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1815 | ||
1816 | if (stopping) | |
1817 | { | |
1818 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1819 | makes it so that the LWP reports an immediate syscall return, | |
1820 | followed by the SIGSTOP. Skip seeing that "return" using | |
1821 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1822 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1823 | entry event. If we didn't do this (and returned 0), we'd | |
1824 | leave a syscall entry pending, and our caller, by using | |
1825 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1826 | itself. Later, when the user re-resumes this LWP, we'd see | |
1827 | another syscall entry event and we'd mistake it for a return. | |
1828 | ||
1829 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1830 | (leaving immediately with LWP->signalled set, without issuing | |
1831 | a PTRACE_CONT), it would still be problematic to leave this | |
1832 | syscall enter pending, as later when the thread is resumed, | |
1833 | it would then see the same syscall exit mentioned above, | |
1834 | followed by the delayed SIGSTOP, while the syscall didn't | |
1835 | actually get to execute. It seems it would be even more | |
1836 | confusing to the user. */ | |
1837 | ||
1838 | if (debug_linux_nat) | |
1839 | fprintf_unfiltered (gdb_stdlog, | |
1840 | "LHST: ignoring syscall %d " | |
1841 | "for LWP %ld (stopping threads), " | |
1842 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1843 | syscall_number, | |
dfd4cc63 | 1844 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1845 | |
1846 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1847 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1848 | lp->stopped = 0; |
ca2163eb PA |
1849 | return 1; |
1850 | } | |
1851 | ||
1852 | if (catch_syscall_enabled ()) | |
1853 | { | |
1854 | /* Always update the entry/return state, even if this particular | |
1855 | syscall isn't interesting to the core now. In async mode, | |
1856 | the user could install a new catchpoint for this syscall | |
1857 | between syscall enter/return, and we'll need to know to | |
1858 | report a syscall return if that happens. */ | |
1859 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1860 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1861 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1862 | ||
1863 | if (catching_syscall_number (syscall_number)) | |
1864 | { | |
1865 | /* Alright, an event to report. */ | |
1866 | ourstatus->kind = lp->syscall_state; | |
1867 | ourstatus->value.syscall_number = syscall_number; | |
1868 | ||
1869 | if (debug_linux_nat) | |
1870 | fprintf_unfiltered (gdb_stdlog, | |
1871 | "LHST: stopping for %s of syscall %d" | |
1872 | " for LWP %ld\n", | |
3e43a32a MS |
1873 | lp->syscall_state |
1874 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1875 | ? "entry" : "return", |
1876 | syscall_number, | |
dfd4cc63 | 1877 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1878 | return 0; |
1879 | } | |
1880 | ||
1881 | if (debug_linux_nat) | |
1882 | fprintf_unfiltered (gdb_stdlog, | |
1883 | "LHST: ignoring %s of syscall %d " | |
1884 | "for LWP %ld\n", | |
1885 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1886 | ? "entry" : "return", | |
1887 | syscall_number, | |
dfd4cc63 | 1888 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1889 | } |
1890 | else | |
1891 | { | |
1892 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1893 | before on this LWP, it could happen that the user removes all | |
1894 | syscall catchpoints before we get to process this event. | |
1895 | There are two noteworthy issues here: | |
1896 | ||
1897 | - When stopped at a syscall entry event, resuming with | |
1898 | PT_STEP still resumes executing the syscall and reports a | |
1899 | syscall return. | |
1900 | ||
1901 | - Only PT_SYSCALL catches syscall enters. If we last | |
1902 | single-stepped this thread, then this event can't be a | |
1903 | syscall enter. If we last single-stepped this thread, this | |
1904 | has to be a syscall exit. | |
1905 | ||
1906 | The points above mean that the next resume, be it PT_STEP or | |
1907 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1908 | if (debug_linux_nat) | |
1909 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1910 | "LHST: caught syscall event " |
1911 | "with no syscall catchpoints." | |
ca2163eb PA |
1912 | " %d for LWP %ld, ignoring\n", |
1913 | syscall_number, | |
dfd4cc63 | 1914 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1915 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1916 | } | |
1917 | ||
1918 | /* The core isn't interested in this event. For efficiency, avoid | |
1919 | stopping all threads only to have the core resume them all again. | |
1920 | Since we're not stopping threads, if we're still syscall tracing | |
1921 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1922 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1923 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1924 | ||
8a99810d | 1925 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1926 | return 1; |
1927 | } | |
1928 | ||
3d799a95 DJ |
1929 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1930 | event, we need to add the new LWP to our list (and not report the | |
1931 | trap to higher layers). This function returns non-zero if the | |
1932 | event should be ignored and we should wait again. If STOPPING is | |
1933 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1934 | |
1935 | static int | |
3d799a95 DJ |
1936 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1937 | int stopping) | |
d6b0e80f | 1938 | { |
dfd4cc63 | 1939 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1940 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
89a5711c | 1941 | int event = linux_ptrace_get_extended_event (status); |
d6b0e80f | 1942 | |
3d799a95 DJ |
1943 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1944 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1945 | { |
3d799a95 DJ |
1946 | unsigned long new_pid; |
1947 | int ret; | |
1948 | ||
1949 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1950 | |
3d799a95 DJ |
1951 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1952 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1953 | { | |
1954 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1955 | hits the SIGSTOP, but we're already attached. */ | |
1956 | ret = my_waitpid (new_pid, &status, | |
1957 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
1958 | if (ret == -1) | |
1959 | perror_with_name (_("waiting for new child")); | |
1960 | else if (ret != new_pid) | |
1961 | internal_error (__FILE__, __LINE__, | |
1962 | _("wait returned unexpected PID %d"), ret); | |
1963 | else if (!WIFSTOPPED (status)) | |
1964 | internal_error (__FILE__, __LINE__, | |
1965 | _("wait returned unexpected status 0x%x"), status); | |
1966 | } | |
1967 | ||
3a3e9ee3 | 1968 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 1969 | |
26cb8b7c PA |
1970 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
1971 | { | |
1972 | /* The arch-specific native code may need to know about new | |
1973 | forks even if those end up never mapped to an | |
1974 | inferior. */ | |
1975 | if (linux_nat_new_fork != NULL) | |
1976 | linux_nat_new_fork (lp, new_pid); | |
1977 | } | |
1978 | ||
2277426b | 1979 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 1980 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 1981 | { |
2277426b PA |
1982 | /* Handle checkpointing by linux-fork.c here as a special |
1983 | case. We don't want the follow-fork-mode or 'catch fork' | |
1984 | to interfere with this. */ | |
1985 | ||
1986 | /* This won't actually modify the breakpoint list, but will | |
1987 | physically remove the breakpoints from the child. */ | |
d80ee84f | 1988 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
1989 | |
1990 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
1991 | if (!find_fork_pid (new_pid)) |
1992 | add_fork (new_pid); | |
2277426b PA |
1993 | |
1994 | /* Report as spurious, so that infrun doesn't want to follow | |
1995 | this fork. We're actually doing an infcall in | |
1996 | linux-fork.c. */ | |
1997 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
1998 | |
1999 | /* Report the stop to the core. */ | |
2000 | return 0; | |
2001 | } | |
2002 | ||
3d799a95 DJ |
2003 | if (event == PTRACE_EVENT_FORK) |
2004 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2005 | else if (event == PTRACE_EVENT_VFORK) | |
2006 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2007 | else |
3d799a95 | 2008 | { |
78768c4a JK |
2009 | struct lwp_info *new_lp; |
2010 | ||
3d799a95 | 2011 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2012 | |
3c4d7e12 PA |
2013 | if (debug_linux_nat) |
2014 | fprintf_unfiltered (gdb_stdlog, | |
2015 | "LHEW: Got clone event " | |
2016 | "from LWP %d, new child is LWP %ld\n", | |
2017 | pid, new_pid); | |
2018 | ||
dfd4cc63 | 2019 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2020 | new_lp->cloned = 1; |
4c28f408 | 2021 | new_lp->stopped = 1; |
d6b0e80f | 2022 | |
3d799a95 DJ |
2023 | if (WSTOPSIG (status) != SIGSTOP) |
2024 | { | |
2025 | /* This can happen if someone starts sending signals to | |
2026 | the new thread before it gets a chance to run, which | |
2027 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2028 | This is an unlikely case, and harder to handle for | |
2029 | fork / vfork than for clone, so we do not try - but | |
2030 | we handle it for clone events here. We'll send | |
2031 | the other signal on to the thread below. */ | |
2032 | ||
2033 | new_lp->signalled = 1; | |
2034 | } | |
2035 | else | |
79395f92 PA |
2036 | { |
2037 | struct thread_info *tp; | |
2038 | ||
2039 | /* When we stop for an event in some other thread, and | |
2040 | pull the thread list just as this thread has cloned, | |
2041 | we'll have seen the new thread in the thread_db list | |
2042 | before handling the CLONE event (glibc's | |
2043 | pthread_create adds the new thread to the thread list | |
2044 | before clone'ing, and has the kernel fill in the | |
2045 | thread's tid on the clone call with | |
2046 | CLONE_PARENT_SETTID). If that happened, and the core | |
2047 | had requested the new thread to stop, we'll have | |
2048 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2049 | RT signal, it can only be queued once. We need to be | |
2050 | careful to not resume the LWP if we wanted it to | |
2051 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2052 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2053 | tp = find_thread_ptid (new_lp->ptid); |
2054 | if (tp != NULL && tp->stop_requested) | |
2055 | new_lp->last_resume_kind = resume_stop; | |
2056 | else | |
2057 | status = 0; | |
2058 | } | |
d6b0e80f | 2059 | |
2db9a427 PA |
2060 | /* If the thread_db layer is active, let it record the user |
2061 | level thread id and status, and add the thread to GDB's | |
2062 | list. */ | |
2063 | if (!thread_db_notice_clone (lp->ptid, new_lp->ptid)) | |
3d799a95 | 2064 | { |
2db9a427 PA |
2065 | /* The process is not using thread_db. Add the LWP to |
2066 | GDB's list. */ | |
2067 | target_post_attach (ptid_get_lwp (new_lp->ptid)); | |
2068 | add_thread (new_lp->ptid); | |
2069 | } | |
4c28f408 | 2070 | |
2db9a427 PA |
2071 | if (!stopping) |
2072 | { | |
2073 | set_running (new_lp->ptid, 1); | |
2074 | set_executing (new_lp->ptid, 1); | |
2075 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced | |
2076 | resume_stop. */ | |
2077 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2078 | } |
2079 | ||
79395f92 PA |
2080 | if (status != 0) |
2081 | { | |
2082 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2083 | gdb_assert (new_lp->status == 0); | |
2084 | ||
2085 | /* Save the wait status to report later. */ | |
2086 | if (debug_linux_nat) | |
2087 | fprintf_unfiltered (gdb_stdlog, | |
2088 | "LHEW: waitpid of new LWP %ld, " | |
2089 | "saving status %s\n", | |
dfd4cc63 | 2090 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2091 | status_to_str (status)); |
2092 | new_lp->status = status; | |
2093 | } | |
2094 | ||
20ba1ce6 | 2095 | new_lp->resumed = !stopping; |
3d799a95 DJ |
2096 | return 1; |
2097 | } | |
2098 | ||
2099 | return 0; | |
d6b0e80f AC |
2100 | } |
2101 | ||
3d799a95 DJ |
2102 | if (event == PTRACE_EVENT_EXEC) |
2103 | { | |
a75724bc PA |
2104 | if (debug_linux_nat) |
2105 | fprintf_unfiltered (gdb_stdlog, | |
2106 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2107 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2108 | |
3d799a95 DJ |
2109 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2110 | ourstatus->value.execd_pathname | |
8dd27370 | 2111 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2112 | |
8af756ef PA |
2113 | /* The thread that execed must have been resumed, but, when a |
2114 | thread execs, it changes its tid to the tgid, and the old | |
2115 | tgid thread might have not been resumed. */ | |
2116 | lp->resumed = 1; | |
6c95b8df PA |
2117 | return 0; |
2118 | } | |
2119 | ||
2120 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2121 | { | |
2122 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2123 | { |
6c95b8df | 2124 | if (debug_linux_nat) |
3e43a32a MS |
2125 | fprintf_unfiltered (gdb_stdlog, |
2126 | "LHEW: Got expected PTRACE_EVENT_" | |
2127 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2128 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2129 | |
6c95b8df PA |
2130 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2131 | return 0; | |
3d799a95 DJ |
2132 | } |
2133 | ||
6c95b8df | 2134 | if (debug_linux_nat) |
3e43a32a MS |
2135 | fprintf_unfiltered (gdb_stdlog, |
2136 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
20ba1ce6 | 2137 | "from LWP %ld: ignoring\n", |
dfd4cc63 | 2138 | ptid_get_lwp (lp->ptid)); |
6c95b8df | 2139 | return 1; |
3d799a95 DJ |
2140 | } |
2141 | ||
2142 | internal_error (__FILE__, __LINE__, | |
2143 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2144 | } |
2145 | ||
2146 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2147 | exited. */ | |
2148 | ||
2149 | static int | |
2150 | wait_lwp (struct lwp_info *lp) | |
2151 | { | |
2152 | pid_t pid; | |
432b4d03 | 2153 | int status = 0; |
d6b0e80f | 2154 | int thread_dead = 0; |
432b4d03 | 2155 | sigset_t prev_mask; |
d6b0e80f AC |
2156 | |
2157 | gdb_assert (!lp->stopped); | |
2158 | gdb_assert (lp->status == 0); | |
2159 | ||
432b4d03 JK |
2160 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2161 | block_child_signals (&prev_mask); | |
2162 | ||
2163 | for (;;) | |
d6b0e80f | 2164 | { |
432b4d03 JK |
2165 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2166 | was right and we should just call sigsuspend. */ | |
2167 | ||
dfd4cc63 | 2168 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2169 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2170 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2171 | if (pid == -1 && errno == ECHILD) |
2172 | { | |
2173 | /* The thread has previously exited. We need to delete it | |
2174 | now because, for some vendor 2.4 kernels with NPTL | |
2175 | support backported, there won't be an exit event unless | |
2176 | it is the main thread. 2.6 kernels will report an exit | |
2177 | event for each thread that exits, as expected. */ | |
2178 | thread_dead = 1; | |
2179 | if (debug_linux_nat) | |
2180 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2181 | target_pid_to_str (lp->ptid)); | |
2182 | } | |
432b4d03 JK |
2183 | if (pid != 0) |
2184 | break; | |
2185 | ||
2186 | /* Bugs 10970, 12702. | |
2187 | Thread group leader may have exited in which case we'll lock up in | |
2188 | waitpid if there are other threads, even if they are all zombies too. | |
2189 | Basically, we're not supposed to use waitpid this way. | |
2190 | __WCLONE is not applicable for the leader so we can't use that. | |
2191 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2192 | process; it gets ESRCH both for the zombie and for running processes. | |
2193 | ||
2194 | As a workaround, check if we're waiting for the thread group leader and | |
2195 | if it's a zombie, and avoid calling waitpid if it is. | |
2196 | ||
2197 | This is racy, what if the tgl becomes a zombie right after we check? | |
2198 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2199 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2200 | |
dfd4cc63 LM |
2201 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2202 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2203 | { |
d6b0e80f AC |
2204 | thread_dead = 1; |
2205 | if (debug_linux_nat) | |
432b4d03 JK |
2206 | fprintf_unfiltered (gdb_stdlog, |
2207 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2208 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2209 | break; |
d6b0e80f | 2210 | } |
432b4d03 JK |
2211 | |
2212 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2213 | get invoked despite our caller had them intentionally blocked by | |
2214 | block_child_signals. This is sensitive only to the loop of | |
2215 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2216 | again before it gets to sigsuspend so we can safely let the handlers | |
2217 | get executed here. */ | |
2218 | ||
d36bf488 DE |
2219 | if (debug_linux_nat) |
2220 | fprintf_unfiltered (gdb_stdlog, "WL: about to sigsuspend\n"); | |
432b4d03 JK |
2221 | sigsuspend (&suspend_mask); |
2222 | } | |
2223 | ||
2224 | restore_child_signals_mask (&prev_mask); | |
2225 | ||
d6b0e80f AC |
2226 | if (!thread_dead) |
2227 | { | |
dfd4cc63 | 2228 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2229 | |
2230 | if (debug_linux_nat) | |
2231 | { | |
2232 | fprintf_unfiltered (gdb_stdlog, | |
2233 | "WL: waitpid %s received %s\n", | |
2234 | target_pid_to_str (lp->ptid), | |
2235 | status_to_str (status)); | |
2236 | } | |
d6b0e80f | 2237 | |
a9f4bb21 PA |
2238 | /* Check if the thread has exited. */ |
2239 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2240 | { | |
2241 | thread_dead = 1; | |
2242 | if (debug_linux_nat) | |
2243 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2244 | target_pid_to_str (lp->ptid)); | |
2245 | } | |
d6b0e80f AC |
2246 | } |
2247 | ||
2248 | if (thread_dead) | |
2249 | { | |
e26af52f | 2250 | exit_lwp (lp); |
d6b0e80f AC |
2251 | return 0; |
2252 | } | |
2253 | ||
2254 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2255 | lp->stopped = 1; |
d6b0e80f | 2256 | |
8784d563 PA |
2257 | if (lp->must_set_ptrace_flags) |
2258 | { | |
2259 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
2260 | ||
2261 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), inf->attach_flag); | |
2262 | lp->must_set_ptrace_flags = 0; | |
2263 | } | |
2264 | ||
ca2163eb PA |
2265 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2266 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2267 | { | |
2268 | /* No longer need the sysgood bit. The ptrace event ends up | |
2269 | recorded in lp->waitstatus if we care for it. We can carry | |
2270 | on handling the event like a regular SIGTRAP from here | |
2271 | on. */ | |
2272 | status = W_STOPCODE (SIGTRAP); | |
2273 | if (linux_handle_syscall_trap (lp, 1)) | |
2274 | return wait_lwp (lp); | |
2275 | } | |
2276 | ||
d6b0e80f | 2277 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
2278 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
2279 | && linux_is_extended_waitstatus (status)) | |
d6b0e80f AC |
2280 | { |
2281 | if (debug_linux_nat) | |
2282 | fprintf_unfiltered (gdb_stdlog, | |
2283 | "WL: Handling extended status 0x%06x\n", | |
2284 | status); | |
20ba1ce6 PA |
2285 | linux_handle_extended_wait (lp, status, 1); |
2286 | return 0; | |
d6b0e80f AC |
2287 | } |
2288 | ||
2289 | return status; | |
2290 | } | |
2291 | ||
2292 | /* Send a SIGSTOP to LP. */ | |
2293 | ||
2294 | static int | |
2295 | stop_callback (struct lwp_info *lp, void *data) | |
2296 | { | |
2297 | if (!lp->stopped && !lp->signalled) | |
2298 | { | |
2299 | int ret; | |
2300 | ||
2301 | if (debug_linux_nat) | |
2302 | { | |
2303 | fprintf_unfiltered (gdb_stdlog, | |
2304 | "SC: kill %s **<SIGSTOP>**\n", | |
2305 | target_pid_to_str (lp->ptid)); | |
2306 | } | |
2307 | errno = 0; | |
dfd4cc63 | 2308 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2309 | if (debug_linux_nat) |
2310 | { | |
2311 | fprintf_unfiltered (gdb_stdlog, | |
2312 | "SC: lwp kill %d %s\n", | |
2313 | ret, | |
2314 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2315 | } | |
2316 | ||
2317 | lp->signalled = 1; | |
2318 | gdb_assert (lp->status == 0); | |
2319 | } | |
2320 | ||
2321 | return 0; | |
2322 | } | |
2323 | ||
7b50312a PA |
2324 | /* Request a stop on LWP. */ |
2325 | ||
2326 | void | |
2327 | linux_stop_lwp (struct lwp_info *lwp) | |
2328 | { | |
2329 | stop_callback (lwp, NULL); | |
2330 | } | |
2331 | ||
2db9a427 PA |
2332 | /* See linux-nat.h */ |
2333 | ||
2334 | void | |
2335 | linux_stop_and_wait_all_lwps (void) | |
2336 | { | |
2337 | /* Stop all LWP's ... */ | |
2338 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); | |
2339 | ||
2340 | /* ... and wait until all of them have reported back that | |
2341 | they're no longer running. */ | |
2342 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); | |
2343 | } | |
2344 | ||
2345 | /* See linux-nat.h */ | |
2346 | ||
2347 | void | |
2348 | linux_unstop_all_lwps (void) | |
2349 | { | |
2350 | iterate_over_lwps (minus_one_ptid, | |
2351 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
2352 | } | |
2353 | ||
57380f4e | 2354 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2355 | |
2356 | static int | |
57380f4e DJ |
2357 | linux_nat_has_pending_sigint (int pid) |
2358 | { | |
2359 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2360 | |
2361 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2362 | ||
2363 | if (sigismember (&pending, SIGINT) | |
2364 | && !sigismember (&ignored, SIGINT)) | |
2365 | return 1; | |
2366 | ||
2367 | return 0; | |
2368 | } | |
2369 | ||
2370 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2371 | ||
2372 | static int | |
2373 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2374 | { |
57380f4e DJ |
2375 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2376 | flag to consume the next one. */ | |
2377 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2378 | && WSTOPSIG (lp->status) == SIGINT) | |
2379 | lp->status = 0; | |
2380 | else | |
2381 | lp->ignore_sigint = 1; | |
2382 | ||
2383 | return 0; | |
2384 | } | |
2385 | ||
2386 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2387 | This function is called after we know the LWP has stopped; if the LWP | |
2388 | stopped before the expected SIGINT was delivered, then it will never have | |
2389 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2390 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2391 | |
57380f4e DJ |
2392 | static void |
2393 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2394 | { | |
2395 | if (!lp->ignore_sigint) | |
2396 | return; | |
2397 | ||
dfd4cc63 | 2398 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2399 | { |
2400 | if (debug_linux_nat) | |
2401 | fprintf_unfiltered (gdb_stdlog, | |
2402 | "MCIS: Clearing bogus flag for %s\n", | |
2403 | target_pid_to_str (lp->ptid)); | |
2404 | lp->ignore_sigint = 0; | |
2405 | } | |
2406 | } | |
2407 | ||
ebec9a0f PA |
2408 | /* Fetch the possible triggered data watchpoint info and store it in |
2409 | LP. | |
2410 | ||
2411 | On some archs, like x86, that use debug registers to set | |
2412 | watchpoints, it's possible that the way to know which watched | |
2413 | address trapped, is to check the register that is used to select | |
2414 | which address to watch. Problem is, between setting the watchpoint | |
2415 | and reading back which data address trapped, the user may change | |
2416 | the set of watchpoints, and, as a consequence, GDB changes the | |
2417 | debug registers in the inferior. To avoid reading back a stale | |
2418 | stopped-data-address when that happens, we cache in LP the fact | |
2419 | that a watchpoint trapped, and the corresponding data address, as | |
2420 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2421 | registers meanwhile, we have the cached data we can rely on. */ | |
2422 | ||
9c02b525 PA |
2423 | static int |
2424 | check_stopped_by_watchpoint (struct lwp_info *lp) | |
ebec9a0f PA |
2425 | { |
2426 | struct cleanup *old_chain; | |
2427 | ||
2428 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
9c02b525 | 2429 | return 0; |
ebec9a0f PA |
2430 | |
2431 | old_chain = save_inferior_ptid (); | |
2432 | inferior_ptid = lp->ptid; | |
2433 | ||
9c02b525 | 2434 | if (linux_ops->to_stopped_by_watchpoint (linux_ops)) |
ebec9a0f | 2435 | { |
15c66dd6 | 2436 | lp->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 | 2437 | |
ebec9a0f PA |
2438 | if (linux_ops->to_stopped_data_address != NULL) |
2439 | lp->stopped_data_address_p = | |
2440 | linux_ops->to_stopped_data_address (¤t_target, | |
2441 | &lp->stopped_data_address); | |
2442 | else | |
2443 | lp->stopped_data_address_p = 0; | |
2444 | } | |
2445 | ||
2446 | do_cleanups (old_chain); | |
9c02b525 | 2447 | |
15c66dd6 | 2448 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 PA |
2449 | } |
2450 | ||
2451 | /* Called when the LWP stopped for a trap that could be explained by a | |
2452 | watchpoint or a breakpoint. */ | |
2453 | ||
2454 | static void | |
2455 | save_sigtrap (struct lwp_info *lp) | |
2456 | { | |
15c66dd6 | 2457 | gdb_assert (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON); |
9c02b525 PA |
2458 | gdb_assert (lp->status != 0); |
2459 | ||
faf09f01 PA |
2460 | /* Check first if this was a SW/HW breakpoint before checking |
2461 | watchpoints, because at least s390 can't tell the data address of | |
2462 | hardware watchpoint hits, and the kernel returns | |
2463 | stopped-by-watchpoint as long as there's a watchpoint set. */ | |
9c02b525 PA |
2464 | if (linux_nat_status_is_event (lp->status)) |
2465 | check_stopped_by_breakpoint (lp); | |
faf09f01 PA |
2466 | |
2467 | /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint | |
2468 | or hardware watchpoint. Check which is which if we got | |
2469 | TARGET_STOPPED_BY_HW_BREAKPOINT. */ | |
2470 | if (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON | |
2471 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
2472 | check_stopped_by_watchpoint (lp); | |
ebec9a0f PA |
2473 | } |
2474 | ||
9c02b525 | 2475 | /* Returns true if the LWP had stopped for a watchpoint. */ |
ebec9a0f PA |
2476 | |
2477 | static int | |
6a109b6b | 2478 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2479 | { |
2480 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2481 | ||
2482 | gdb_assert (lp != NULL); | |
2483 | ||
15c66dd6 | 2484 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
ebec9a0f PA |
2485 | } |
2486 | ||
2487 | static int | |
2488 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2489 | { | |
2490 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2491 | ||
2492 | gdb_assert (lp != NULL); | |
2493 | ||
2494 | *addr_p = lp->stopped_data_address; | |
2495 | ||
2496 | return lp->stopped_data_address_p; | |
2497 | } | |
2498 | ||
26ab7092 JK |
2499 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2500 | ||
2501 | static int | |
2502 | sigtrap_is_event (int status) | |
2503 | { | |
2504 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2505 | } | |
2506 | ||
26ab7092 JK |
2507 | /* Set alternative SIGTRAP-like events recognizer. If |
2508 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2509 | applied. */ | |
2510 | ||
2511 | void | |
2512 | linux_nat_set_status_is_event (struct target_ops *t, | |
2513 | int (*status_is_event) (int status)) | |
2514 | { | |
2515 | linux_nat_status_is_event = status_is_event; | |
2516 | } | |
2517 | ||
57380f4e DJ |
2518 | /* Wait until LP is stopped. */ |
2519 | ||
2520 | static int | |
2521 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2522 | { | |
c9657e70 | 2523 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
6c95b8df PA |
2524 | |
2525 | /* If this is a vfork parent, bail out, it is not going to report | |
2526 | any SIGSTOP until the vfork is done with. */ | |
2527 | if (inf->vfork_child != NULL) | |
2528 | return 0; | |
2529 | ||
d6b0e80f AC |
2530 | if (!lp->stopped) |
2531 | { | |
2532 | int status; | |
2533 | ||
2534 | status = wait_lwp (lp); | |
2535 | if (status == 0) | |
2536 | return 0; | |
2537 | ||
57380f4e DJ |
2538 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2539 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2540 | { |
57380f4e | 2541 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2542 | |
2543 | errno = 0; | |
dfd4cc63 | 2544 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2545 | lp->stopped = 0; |
d6b0e80f AC |
2546 | if (debug_linux_nat) |
2547 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2548 | "PTRACE_CONT %s, 0, 0 (%s) " |
2549 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2550 | target_pid_to_str (lp->ptid), |
2551 | errno ? safe_strerror (errno) : "OK"); | |
2552 | ||
57380f4e | 2553 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2554 | } |
2555 | ||
57380f4e DJ |
2556 | maybe_clear_ignore_sigint (lp); |
2557 | ||
d6b0e80f AC |
2558 | if (WSTOPSIG (status) != SIGSTOP) |
2559 | { | |
e5ef252a | 2560 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2561 | |
e5ef252a PA |
2562 | if (debug_linux_nat) |
2563 | fprintf_unfiltered (gdb_stdlog, | |
2564 | "SWC: Pending event %s in %s\n", | |
2565 | status_to_str ((int) status), | |
2566 | target_pid_to_str (lp->ptid)); | |
2567 | ||
2568 | /* Save the sigtrap event. */ | |
2569 | lp->status = status; | |
e5ef252a | 2570 | gdb_assert (lp->signalled); |
9c02b525 | 2571 | save_sigtrap (lp); |
d6b0e80f AC |
2572 | } |
2573 | else | |
2574 | { | |
2575 | /* We caught the SIGSTOP that we intended to catch, so | |
2576 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2577 | |
2578 | if (debug_linux_nat) | |
2579 | fprintf_unfiltered (gdb_stdlog, | |
2580 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2581 | target_pid_to_str (lp->ptid)); | |
2582 | ||
e5ef252a PA |
2583 | /* Reset SIGNALLED only after the stop_wait_callback call |
2584 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2585 | lp->signalled = 0; |
2586 | } | |
2587 | } | |
2588 | ||
2589 | return 0; | |
2590 | } | |
2591 | ||
9c02b525 PA |
2592 | /* Return non-zero if LP has a wait status pending. Discard the |
2593 | pending event and resume the LWP if the event that originally | |
2594 | caused the stop became uninteresting. */ | |
d6b0e80f AC |
2595 | |
2596 | static int | |
2597 | status_callback (struct lwp_info *lp, void *data) | |
2598 | { | |
2599 | /* Only report a pending wait status if we pretend that this has | |
2600 | indeed been resumed. */ | |
ca2163eb PA |
2601 | if (!lp->resumed) |
2602 | return 0; | |
2603 | ||
eb54c8bf PA |
2604 | if (!lwp_status_pending_p (lp)) |
2605 | return 0; | |
2606 | ||
15c66dd6 PA |
2607 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
2608 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
9c02b525 PA |
2609 | { |
2610 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
2611 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2612 | CORE_ADDR pc; | |
2613 | int discard = 0; | |
2614 | ||
9c02b525 PA |
2615 | pc = regcache_read_pc (regcache); |
2616 | ||
2617 | if (pc != lp->stop_pc) | |
2618 | { | |
2619 | if (debug_linux_nat) | |
2620 | fprintf_unfiltered (gdb_stdlog, | |
2621 | "SC: PC of %s changed. was=%s, now=%s\n", | |
2622 | target_pid_to_str (lp->ptid), | |
2623 | paddress (target_gdbarch (), lp->stop_pc), | |
2624 | paddress (target_gdbarch (), pc)); | |
2625 | discard = 1; | |
2626 | } | |
faf09f01 PA |
2627 | |
2628 | #if !USE_SIGTRAP_SIGINFO | |
9c02b525 PA |
2629 | else if (!breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2630 | { | |
2631 | if (debug_linux_nat) | |
2632 | fprintf_unfiltered (gdb_stdlog, | |
2633 | "SC: previous breakpoint of %s, at %s gone\n", | |
2634 | target_pid_to_str (lp->ptid), | |
2635 | paddress (target_gdbarch (), lp->stop_pc)); | |
2636 | ||
2637 | discard = 1; | |
2638 | } | |
faf09f01 | 2639 | #endif |
9c02b525 PA |
2640 | |
2641 | if (discard) | |
2642 | { | |
2643 | if (debug_linux_nat) | |
2644 | fprintf_unfiltered (gdb_stdlog, | |
2645 | "SC: pending event of %s cancelled.\n", | |
2646 | target_pid_to_str (lp->ptid)); | |
2647 | ||
2648 | lp->status = 0; | |
2649 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); | |
2650 | return 0; | |
2651 | } | |
9c02b525 PA |
2652 | } |
2653 | ||
eb54c8bf | 2654 | return 1; |
d6b0e80f AC |
2655 | } |
2656 | ||
2657 | /* Return non-zero if LP isn't stopped. */ | |
2658 | ||
2659 | static int | |
2660 | running_callback (struct lwp_info *lp, void *data) | |
2661 | { | |
25289eb2 | 2662 | return (!lp->stopped |
8a99810d | 2663 | || (lwp_status_pending_p (lp) && lp->resumed)); |
d6b0e80f AC |
2664 | } |
2665 | ||
2666 | /* Count the LWP's that have had events. */ | |
2667 | ||
2668 | static int | |
2669 | count_events_callback (struct lwp_info *lp, void *data) | |
2670 | { | |
2671 | int *count = data; | |
2672 | ||
2673 | gdb_assert (count != NULL); | |
2674 | ||
9c02b525 PA |
2675 | /* Select only resumed LWPs that have an event pending. */ |
2676 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2677 | (*count)++; |
2678 | ||
2679 | return 0; | |
2680 | } | |
2681 | ||
2682 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2683 | ||
2684 | static int | |
2685 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2686 | { | |
25289eb2 PA |
2687 | if (lp->last_resume_kind == resume_step |
2688 | && lp->status != 0) | |
d6b0e80f AC |
2689 | return 1; |
2690 | else | |
2691 | return 0; | |
2692 | } | |
2693 | ||
8a99810d PA |
2694 | /* Returns true if LP has a status pending. */ |
2695 | ||
2696 | static int | |
2697 | lwp_status_pending_p (struct lwp_info *lp) | |
2698 | { | |
2699 | /* We check for lp->waitstatus in addition to lp->status, because we | |
2700 | can have pending process exits recorded in lp->status and | |
2701 | W_EXITCODE(0,0) happens to be 0. */ | |
2702 | return lp->status != 0 || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE; | |
2703 | } | |
2704 | ||
b90fc188 | 2705 | /* Select the Nth LWP that has had an event. */ |
d6b0e80f AC |
2706 | |
2707 | static int | |
2708 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2709 | { | |
2710 | int *selector = data; | |
2711 | ||
2712 | gdb_assert (selector != NULL); | |
2713 | ||
9c02b525 PA |
2714 | /* Select only resumed LWPs that have an event pending. */ |
2715 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2716 | if ((*selector)-- == 0) |
2717 | return 1; | |
2718 | ||
2719 | return 0; | |
2720 | } | |
2721 | ||
9c02b525 PA |
2722 | /* Called when the LWP got a signal/trap that could be explained by a |
2723 | software or hardware breakpoint. */ | |
2724 | ||
710151dd | 2725 | static int |
9c02b525 | 2726 | check_stopped_by_breakpoint (struct lwp_info *lp) |
710151dd PA |
2727 | { |
2728 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2729 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2730 | LWP. We will handle the current event, eventually we will resume | |
2731 | this LWP, and this breakpoint will trap again. | |
2732 | ||
2733 | If we do not do this, then we run the risk that the user will | |
2734 | delete or disable the breakpoint, but the LWP will have already | |
2735 | tripped on it. */ | |
2736 | ||
515630c5 UW |
2737 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2738 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2739 | CORE_ADDR pc; | |
9c02b525 | 2740 | CORE_ADDR sw_bp_pc; |
faf09f01 PA |
2741 | #if USE_SIGTRAP_SIGINFO |
2742 | siginfo_t siginfo; | |
2743 | #endif | |
9c02b525 PA |
2744 | |
2745 | pc = regcache_read_pc (regcache); | |
527a273a | 2746 | sw_bp_pc = pc - gdbarch_decr_pc_after_break (gdbarch); |
515630c5 | 2747 | |
faf09f01 PA |
2748 | #if USE_SIGTRAP_SIGINFO |
2749 | if (linux_nat_get_siginfo (lp->ptid, &siginfo)) | |
2750 | { | |
2751 | if (siginfo.si_signo == SIGTRAP) | |
2752 | { | |
2753 | if (siginfo.si_code == GDB_ARCH_TRAP_BRKPT) | |
2754 | { | |
2755 | if (debug_linux_nat) | |
2756 | fprintf_unfiltered (gdb_stdlog, | |
2757 | "CSBB: Push back software " | |
2758 | "breakpoint for %s\n", | |
2759 | target_pid_to_str (lp->ptid)); | |
2760 | ||
2761 | /* Back up the PC if necessary. */ | |
2762 | if (pc != sw_bp_pc) | |
2763 | regcache_write_pc (regcache, sw_bp_pc); | |
2764 | ||
2765 | lp->stop_pc = sw_bp_pc; | |
2766 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2767 | return 1; | |
2768 | } | |
2769 | else if (siginfo.si_code == TRAP_HWBKPT) | |
2770 | { | |
2771 | if (debug_linux_nat) | |
2772 | fprintf_unfiltered (gdb_stdlog, | |
2773 | "CSBB: Push back hardware " | |
2774 | "breakpoint/watchpoint for %s\n", | |
2775 | target_pid_to_str (lp->ptid)); | |
2776 | ||
2777 | lp->stop_pc = pc; | |
2778 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2779 | return 1; | |
2780 | } | |
2781 | } | |
2782 | } | |
2783 | #else | |
9c02b525 PA |
2784 | if ((!lp->step || lp->stop_pc == sw_bp_pc) |
2785 | && software_breakpoint_inserted_here_p (get_regcache_aspace (regcache), | |
2786 | sw_bp_pc)) | |
710151dd | 2787 | { |
9c02b525 PA |
2788 | /* The LWP was either continued, or stepped a software |
2789 | breakpoint instruction. */ | |
710151dd PA |
2790 | if (debug_linux_nat) |
2791 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2792 | "CB: Push back software breakpoint for %s\n", |
710151dd PA |
2793 | target_pid_to_str (lp->ptid)); |
2794 | ||
2795 | /* Back up the PC if necessary. */ | |
9c02b525 PA |
2796 | if (pc != sw_bp_pc) |
2797 | regcache_write_pc (regcache, sw_bp_pc); | |
515630c5 | 2798 | |
9c02b525 | 2799 | lp->stop_pc = sw_bp_pc; |
15c66dd6 | 2800 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
710151dd PA |
2801 | return 1; |
2802 | } | |
710151dd | 2803 | |
9c02b525 PA |
2804 | if (hardware_breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
2805 | { | |
2806 | if (debug_linux_nat) | |
2807 | fprintf_unfiltered (gdb_stdlog, | |
2808 | "CB: Push back hardware breakpoint for %s\n", | |
2809 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 2810 | |
9c02b525 | 2811 | lp->stop_pc = pc; |
15c66dd6 | 2812 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; |
9c02b525 PA |
2813 | return 1; |
2814 | } | |
faf09f01 | 2815 | #endif |
d6b0e80f AC |
2816 | |
2817 | return 0; | |
2818 | } | |
2819 | ||
faf09f01 PA |
2820 | |
2821 | /* Returns true if the LWP had stopped for a software breakpoint. */ | |
2822 | ||
2823 | static int | |
2824 | linux_nat_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2825 | { | |
2826 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2827 | ||
2828 | gdb_assert (lp != NULL); | |
2829 | ||
2830 | return lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2831 | } | |
2832 | ||
2833 | /* Implement the supports_stopped_by_sw_breakpoint method. */ | |
2834 | ||
2835 | static int | |
2836 | linux_nat_supports_stopped_by_sw_breakpoint (struct target_ops *ops) | |
2837 | { | |
2838 | return USE_SIGTRAP_SIGINFO; | |
2839 | } | |
2840 | ||
2841 | /* Returns true if the LWP had stopped for a hardware | |
2842 | breakpoint/watchpoint. */ | |
2843 | ||
2844 | static int | |
2845 | linux_nat_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2846 | { | |
2847 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2848 | ||
2849 | gdb_assert (lp != NULL); | |
2850 | ||
2851 | return lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2852 | } | |
2853 | ||
2854 | /* Implement the supports_stopped_by_hw_breakpoint method. */ | |
2855 | ||
2856 | static int | |
2857 | linux_nat_supports_stopped_by_hw_breakpoint (struct target_ops *ops) | |
2858 | { | |
2859 | return USE_SIGTRAP_SIGINFO; | |
2860 | } | |
2861 | ||
d6b0e80f AC |
2862 | /* Select one LWP out of those that have events pending. */ |
2863 | ||
2864 | static void | |
d90e17a7 | 2865 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2866 | { |
2867 | int num_events = 0; | |
2868 | int random_selector; | |
9c02b525 | 2869 | struct lwp_info *event_lp = NULL; |
d6b0e80f | 2870 | |
ac264b3b | 2871 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2872 | (*orig_lp)->status = *status; |
2873 | ||
9c02b525 PA |
2874 | /* In all-stop, give preference to the LWP that is being |
2875 | single-stepped. There will be at most one, and it will be the | |
2876 | LWP that the core is most interested in. If we didn't do this, | |
2877 | then we'd have to handle pending step SIGTRAPs somehow in case | |
2878 | the core later continues the previously-stepped thread, as | |
2879 | otherwise we'd report the pending SIGTRAP then, and the core, not | |
2880 | having stepped the thread, wouldn't understand what the trap was | |
2881 | for, and therefore would report it to the user as a random | |
2882 | signal. */ | |
2883 | if (!non_stop) | |
d6b0e80f | 2884 | { |
9c02b525 PA |
2885 | event_lp = iterate_over_lwps (filter, |
2886 | select_singlestep_lwp_callback, NULL); | |
2887 | if (event_lp != NULL) | |
2888 | { | |
2889 | if (debug_linux_nat) | |
2890 | fprintf_unfiltered (gdb_stdlog, | |
2891 | "SEL: Select single-step %s\n", | |
2892 | target_pid_to_str (event_lp->ptid)); | |
2893 | } | |
d6b0e80f | 2894 | } |
9c02b525 PA |
2895 | |
2896 | if (event_lp == NULL) | |
d6b0e80f | 2897 | { |
9c02b525 | 2898 | /* Pick one at random, out of those which have had events. */ |
d6b0e80f | 2899 | |
9c02b525 | 2900 | /* First see how many events we have. */ |
d90e17a7 | 2901 | iterate_over_lwps (filter, count_events_callback, &num_events); |
8bf3b159 | 2902 | gdb_assert (num_events > 0); |
d6b0e80f | 2903 | |
9c02b525 PA |
2904 | /* Now randomly pick a LWP out of those that have had |
2905 | events. */ | |
d6b0e80f AC |
2906 | random_selector = (int) |
2907 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2908 | ||
2909 | if (debug_linux_nat && num_events > 1) | |
2910 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2911 | "SEL: Found %d events, selecting #%d\n", |
d6b0e80f AC |
2912 | num_events, random_selector); |
2913 | ||
d90e17a7 PA |
2914 | event_lp = iterate_over_lwps (filter, |
2915 | select_event_lwp_callback, | |
d6b0e80f AC |
2916 | &random_selector); |
2917 | } | |
2918 | ||
2919 | if (event_lp != NULL) | |
2920 | { | |
2921 | /* Switch the event LWP. */ | |
2922 | *orig_lp = event_lp; | |
2923 | *status = event_lp->status; | |
2924 | } | |
2925 | ||
2926 | /* Flush the wait status for the event LWP. */ | |
2927 | (*orig_lp)->status = 0; | |
2928 | } | |
2929 | ||
2930 | /* Return non-zero if LP has been resumed. */ | |
2931 | ||
2932 | static int | |
2933 | resumed_callback (struct lwp_info *lp, void *data) | |
2934 | { | |
2935 | return lp->resumed; | |
2936 | } | |
2937 | ||
12d9289a PA |
2938 | /* Stop an active thread, verify it still exists, then resume it. If |
2939 | the thread ends up with a pending status, then it is not resumed, | |
2940 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2941 | |
2942 | static int | |
2943 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2944 | { | |
25289eb2 | 2945 | if (!lp->stopped) |
d6b0e80f | 2946 | { |
25289eb2 PA |
2947 | ptid_t ptid = lp->ptid; |
2948 | ||
d6b0e80f AC |
2949 | stop_callback (lp, NULL); |
2950 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2951 | |
2952 | /* Resume if the lwp still exists, and the core wanted it | |
2953 | running. */ | |
12d9289a PA |
2954 | lp = find_lwp_pid (ptid); |
2955 | if (lp != NULL) | |
25289eb2 | 2956 | { |
12d9289a | 2957 | if (lp->last_resume_kind == resume_stop |
8a99810d | 2958 | && !lwp_status_pending_p (lp)) |
12d9289a PA |
2959 | { |
2960 | /* The core wanted the LWP to stop. Even if it stopped | |
2961 | cleanly (with SIGSTOP), leave the event pending. */ | |
2962 | if (debug_linux_nat) | |
2963 | fprintf_unfiltered (gdb_stdlog, | |
2964 | "SARC: core wanted LWP %ld stopped " | |
2965 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2966 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2967 | lp->status = W_STOPCODE (SIGSTOP); |
2968 | } | |
2969 | ||
8a99810d | 2970 | if (!lwp_status_pending_p (lp)) |
12d9289a PA |
2971 | { |
2972 | if (debug_linux_nat) | |
2973 | fprintf_unfiltered (gdb_stdlog, | |
2974 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2975 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2976 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2977 | } |
2978 | else | |
2979 | { | |
2980 | if (debug_linux_nat) | |
2981 | fprintf_unfiltered (gdb_stdlog, | |
2982 | "SARC: not re-resuming LWP %ld " | |
2983 | "(has pending)\n", | |
dfd4cc63 | 2984 | ptid_get_lwp (lp->ptid)); |
12d9289a | 2985 | } |
25289eb2 | 2986 | } |
d6b0e80f AC |
2987 | } |
2988 | return 0; | |
2989 | } | |
2990 | ||
02f3fc28 | 2991 | /* Check if we should go on and pass this event to common code. |
9c02b525 | 2992 | Return the affected lwp if we are, or NULL otherwise. */ |
12d9289a | 2993 | |
02f3fc28 | 2994 | static struct lwp_info * |
9c02b525 | 2995 | linux_nat_filter_event (int lwpid, int status) |
02f3fc28 PA |
2996 | { |
2997 | struct lwp_info *lp; | |
89a5711c | 2998 | int event = linux_ptrace_get_extended_event (status); |
02f3fc28 PA |
2999 | |
3000 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
3001 | ||
3002 | /* Check for stop events reported by a process we didn't already | |
3003 | know about - anything not already in our LWP list. | |
3004 | ||
3005 | If we're expecting to receive stopped processes after | |
3006 | fork, vfork, and clone events, then we'll just add the | |
3007 | new one to our list and go back to waiting for the event | |
3008 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
3009 | from waitpid before or after the event is. |
3010 | ||
3011 | But note the case of a non-leader thread exec'ing after the | |
3012 | leader having exited, and gone from our lists. The non-leader | |
3013 | thread changes its tid to the tgid. */ | |
3014 | ||
3015 | if (WIFSTOPPED (status) && lp == NULL | |
89a5711c | 3016 | && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC)) |
0e5bf2a8 PA |
3017 | { |
3018 | /* A multi-thread exec after we had seen the leader exiting. */ | |
3019 | if (debug_linux_nat) | |
3020 | fprintf_unfiltered (gdb_stdlog, | |
3021 | "LLW: Re-adding thread group leader LWP %d.\n", | |
3022 | lwpid); | |
3023 | ||
dfd4cc63 | 3024 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
3025 | lp->stopped = 1; |
3026 | lp->resumed = 1; | |
3027 | add_thread (lp->ptid); | |
3028 | } | |
3029 | ||
02f3fc28 PA |
3030 | if (WIFSTOPPED (status) && !lp) |
3031 | { | |
3b27ef47 PA |
3032 | if (debug_linux_nat) |
3033 | fprintf_unfiltered (gdb_stdlog, | |
3034 | "LHEW: saving LWP %ld status %s in stopped_pids list\n", | |
3035 | (long) lwpid, status_to_str (status)); | |
84636d28 | 3036 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
3037 | return NULL; |
3038 | } | |
3039 | ||
3040 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 3041 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 3042 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
3043 | exits. */ |
3044 | if (!WIFSTOPPED (status) && !lp) | |
3045 | return NULL; | |
3046 | ||
8817a6f2 PA |
3047 | /* This LWP is stopped now. (And if dead, this prevents it from |
3048 | ever being continued.) */ | |
3049 | lp->stopped = 1; | |
3050 | ||
8784d563 PA |
3051 | if (WIFSTOPPED (status) && lp->must_set_ptrace_flags) |
3052 | { | |
3053 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); | |
3054 | ||
3055 | linux_enable_event_reporting (ptid_get_lwp (lp->ptid), inf->attach_flag); | |
3056 | lp->must_set_ptrace_flags = 0; | |
3057 | } | |
3058 | ||
ca2163eb PA |
3059 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
3060 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
3061 | { | |
3062 | /* No longer need the sysgood bit. The ptrace event ends up | |
3063 | recorded in lp->waitstatus if we care for it. We can carry | |
3064 | on handling the event like a regular SIGTRAP from here | |
3065 | on. */ | |
3066 | status = W_STOPCODE (SIGTRAP); | |
3067 | if (linux_handle_syscall_trap (lp, 0)) | |
3068 | return NULL; | |
3069 | } | |
02f3fc28 | 3070 | |
ca2163eb | 3071 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
3072 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
3073 | && linux_is_extended_waitstatus (status)) | |
02f3fc28 PA |
3074 | { |
3075 | if (debug_linux_nat) | |
3076 | fprintf_unfiltered (gdb_stdlog, | |
3077 | "LLW: Handling extended status 0x%06x\n", | |
3078 | status); | |
3079 | if (linux_handle_extended_wait (lp, status, 0)) | |
3080 | return NULL; | |
3081 | } | |
3082 | ||
3083 | /* Check if the thread has exited. */ | |
9c02b525 PA |
3084 | if (WIFEXITED (status) || WIFSIGNALED (status)) |
3085 | { | |
3086 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
02f3fc28 | 3087 | { |
9c02b525 PA |
3088 | /* If this is the main thread, we must stop all threads and |
3089 | verify if they are still alive. This is because in the | |
3090 | nptl thread model on Linux 2.4, there is no signal issued | |
3091 | for exiting LWPs other than the main thread. We only get | |
3092 | the main thread exit signal once all child threads have | |
3093 | already exited. If we stop all the threads and use the | |
3094 | stop_wait_callback to check if they have exited we can | |
3095 | determine whether this signal should be ignored or | |
3096 | whether it means the end of the debugged application, | |
3097 | regardless of which threading model is being used. */ | |
3098 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) | |
3099 | { | |
3100 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3101 | stop_and_resume_callback, NULL); | |
3102 | } | |
3103 | ||
3104 | if (debug_linux_nat) | |
3105 | fprintf_unfiltered (gdb_stdlog, | |
3106 | "LLW: %s exited.\n", | |
3107 | target_pid_to_str (lp->ptid)); | |
3108 | ||
3109 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) | |
3110 | { | |
3111 | /* If there is at least one more LWP, then the exit signal | |
3112 | was not the end of the debugged application and should be | |
3113 | ignored. */ | |
3114 | exit_lwp (lp); | |
3115 | return NULL; | |
3116 | } | |
02f3fc28 PA |
3117 | } |
3118 | ||
9c02b525 PA |
3119 | gdb_assert (lp->resumed); |
3120 | ||
02f3fc28 PA |
3121 | if (debug_linux_nat) |
3122 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 PA |
3123 | "Process %ld exited\n", |
3124 | ptid_get_lwp (lp->ptid)); | |
02f3fc28 | 3125 | |
9c02b525 PA |
3126 | /* This was the last lwp in the process. Since events are |
3127 | serialized to GDB core, we may not be able report this one | |
3128 | right now, but GDB core and the other target layers will want | |
3129 | to be notified about the exit code/signal, leave the status | |
3130 | pending for the next time we're able to report it. */ | |
3131 | ||
3132 | /* Dead LWP's aren't expected to reported a pending sigstop. */ | |
3133 | lp->signalled = 0; | |
3134 | ||
3135 | /* Store the pending event in the waitstatus, because | |
3136 | W_EXITCODE(0,0) == 0. */ | |
3137 | store_waitstatus (&lp->waitstatus, status); | |
3138 | return lp; | |
02f3fc28 PA |
3139 | } |
3140 | ||
3141 | /* Check if the current LWP has previously exited. In the nptl | |
3142 | thread model, LWPs other than the main thread do not issue | |
3143 | signals when they exit so we must check whenever the thread has | |
3144 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3145 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3146 | { |
dfd4cc63 | 3147 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3148 | |
02f3fc28 PA |
3149 | if (debug_linux_nat) |
3150 | fprintf_unfiltered (gdb_stdlog, | |
3151 | "LLW: %s exited.\n", | |
3152 | target_pid_to_str (lp->ptid)); | |
3153 | ||
3154 | exit_lwp (lp); | |
3155 | ||
3156 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3157 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3158 | |
3159 | /* Discard the event. */ | |
3160 | return NULL; | |
3161 | } | |
3162 | ||
3163 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3164 | an attempt to stop an LWP. */ | |
3165 | if (lp->signalled | |
3166 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3167 | { | |
3168 | if (debug_linux_nat) | |
3169 | fprintf_unfiltered (gdb_stdlog, | |
3170 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3171 | target_pid_to_str (lp->ptid)); | |
3172 | ||
02f3fc28 PA |
3173 | lp->signalled = 0; |
3174 | ||
25289eb2 PA |
3175 | if (lp->last_resume_kind != resume_stop) |
3176 | { | |
3177 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3178 | |
8a99810d | 3179 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
25289eb2 PA |
3180 | if (debug_linux_nat) |
3181 | fprintf_unfiltered (gdb_stdlog, | |
3182 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3183 | lp->step ? | |
3184 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3185 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3186 | |
25289eb2 | 3187 | gdb_assert (lp->resumed); |
02f3fc28 | 3188 | |
25289eb2 PA |
3189 | /* Discard the event. */ |
3190 | return NULL; | |
3191 | } | |
02f3fc28 PA |
3192 | } |
3193 | ||
57380f4e DJ |
3194 | /* Make sure we don't report a SIGINT that we have already displayed |
3195 | for another thread. */ | |
3196 | if (lp->ignore_sigint | |
3197 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3198 | { | |
3199 | if (debug_linux_nat) | |
3200 | fprintf_unfiltered (gdb_stdlog, | |
3201 | "LLW: Delayed SIGINT caught for %s.\n", | |
3202 | target_pid_to_str (lp->ptid)); | |
3203 | ||
3204 | /* This is a delayed SIGINT. */ | |
3205 | lp->ignore_sigint = 0; | |
3206 | ||
8a99810d | 3207 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3208 | if (debug_linux_nat) |
3209 | fprintf_unfiltered (gdb_stdlog, | |
3210 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3211 | lp->step ? | |
3212 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3213 | target_pid_to_str (lp->ptid)); | |
57380f4e DJ |
3214 | gdb_assert (lp->resumed); |
3215 | ||
3216 | /* Discard the event. */ | |
3217 | return NULL; | |
3218 | } | |
3219 | ||
9c02b525 PA |
3220 | /* Don't report signals that GDB isn't interested in, such as |
3221 | signals that are neither printed nor stopped upon. Stopping all | |
3222 | threads can be a bit time-consuming so if we want decent | |
3223 | performance with heavily multi-threaded programs, especially when | |
3224 | they're using a high frequency timer, we'd better avoid it if we | |
3225 | can. */ | |
3226 | if (WIFSTOPPED (status)) | |
3227 | { | |
3228 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); | |
3229 | ||
3230 | if (!non_stop) | |
3231 | { | |
3232 | /* Only do the below in all-stop, as we currently use SIGSTOP | |
3233 | to implement target_stop (see linux_nat_stop) in | |
3234 | non-stop. */ | |
3235 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) | |
3236 | { | |
3237 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3238 | forwarded to the entire process group, that is, all LWPs | |
3239 | will receive it - unless they're using CLONE_THREAD to | |
3240 | share signals. Since we only want to report it once, we | |
3241 | mark it as ignored for all LWPs except this one. */ | |
3242 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), | |
3243 | set_ignore_sigint, NULL); | |
3244 | lp->ignore_sigint = 0; | |
3245 | } | |
3246 | else | |
3247 | maybe_clear_ignore_sigint (lp); | |
3248 | } | |
3249 | ||
3250 | /* When using hardware single-step, we need to report every signal. | |
c9587f88 AT |
3251 | Otherwise, signals in pass_mask may be short-circuited |
3252 | except signals that might be caused by a breakpoint. */ | |
9c02b525 | 3253 | if (!lp->step |
c9587f88 AT |
3254 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)) |
3255 | && !linux_wstatus_maybe_breakpoint (status)) | |
9c02b525 PA |
3256 | { |
3257 | linux_resume_one_lwp (lp, lp->step, signo); | |
3258 | if (debug_linux_nat) | |
3259 | fprintf_unfiltered (gdb_stdlog, | |
3260 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3261 | lp->step ? | |
3262 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3263 | target_pid_to_str (lp->ptid), | |
3264 | (signo != GDB_SIGNAL_0 | |
3265 | ? strsignal (gdb_signal_to_host (signo)) | |
3266 | : "0")); | |
3267 | return NULL; | |
3268 | } | |
3269 | } | |
3270 | ||
02f3fc28 PA |
3271 | /* An interesting event. */ |
3272 | gdb_assert (lp); | |
ca2163eb | 3273 | lp->status = status; |
9c02b525 | 3274 | save_sigtrap (lp); |
02f3fc28 PA |
3275 | return lp; |
3276 | } | |
3277 | ||
0e5bf2a8 PA |
3278 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3279 | their exits until all other threads in the group have exited. */ | |
3280 | ||
3281 | static void | |
3282 | check_zombie_leaders (void) | |
3283 | { | |
3284 | struct inferior *inf; | |
3285 | ||
3286 | ALL_INFERIORS (inf) | |
3287 | { | |
3288 | struct lwp_info *leader_lp; | |
3289 | ||
3290 | if (inf->pid == 0) | |
3291 | continue; | |
3292 | ||
3293 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3294 | if (leader_lp != NULL | |
3295 | /* Check if there are other threads in the group, as we may | |
3296 | have raced with the inferior simply exiting. */ | |
3297 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3298 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3299 | { |
3300 | if (debug_linux_nat) | |
3301 | fprintf_unfiltered (gdb_stdlog, | |
3302 | "CZL: Thread group leader %d zombie " | |
3303 | "(it exited, or another thread execd).\n", | |
3304 | inf->pid); | |
3305 | ||
3306 | /* A leader zombie can mean one of two things: | |
3307 | ||
3308 | - It exited, and there's an exit status pending | |
3309 | available, or only the leader exited (not the whole | |
3310 | program). In the latter case, we can't waitpid the | |
3311 | leader's exit status until all other threads are gone. | |
3312 | ||
3313 | - There are 3 or more threads in the group, and a thread | |
3314 | other than the leader exec'd. On an exec, the Linux | |
3315 | kernel destroys all other threads (except the execing | |
3316 | one) in the thread group, and resets the execing thread's | |
3317 | tid to the tgid. No exit notification is sent for the | |
3318 | execing thread -- from the ptracer's perspective, it | |
3319 | appears as though the execing thread just vanishes. | |
3320 | Until we reap all other threads except the leader and the | |
3321 | execing thread, the leader will be zombie, and the | |
3322 | execing thread will be in `D (disc sleep)'. As soon as | |
3323 | all other threads are reaped, the execing thread changes | |
3324 | it's tid to the tgid, and the previous (zombie) leader | |
3325 | vanishes, giving place to the "new" leader. We could try | |
3326 | distinguishing the exit and exec cases, by waiting once | |
3327 | more, and seeing if something comes out, but it doesn't | |
3328 | sound useful. The previous leader _does_ go away, and | |
3329 | we'll re-add the new one once we see the exec event | |
3330 | (which is just the same as what would happen if the | |
3331 | previous leader did exit voluntarily before some other | |
3332 | thread execs). */ | |
3333 | ||
3334 | if (debug_linux_nat) | |
3335 | fprintf_unfiltered (gdb_stdlog, | |
3336 | "CZL: Thread group leader %d vanished.\n", | |
3337 | inf->pid); | |
3338 | exit_lwp (leader_lp); | |
3339 | } | |
3340 | } | |
3341 | } | |
3342 | ||
d6b0e80f | 3343 | static ptid_t |
7feb7d06 | 3344 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3345 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3346 | int target_options) | |
d6b0e80f | 3347 | { |
fc9b8e47 | 3348 | sigset_t prev_mask; |
4b60df3d | 3349 | enum resume_kind last_resume_kind; |
12d9289a | 3350 | struct lwp_info *lp; |
12d9289a | 3351 | int status; |
d6b0e80f | 3352 | |
01124a23 | 3353 | if (debug_linux_nat) |
b84876c2 PA |
3354 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3355 | ||
f973ed9c DJ |
3356 | /* The first time we get here after starting a new inferior, we may |
3357 | not have added it to the LWP list yet - this is the earliest | |
3358 | moment at which we know its PID. */ | |
d90e17a7 | 3359 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3360 | { |
27c9d204 PA |
3361 | /* Upgrade the main thread's ptid. */ |
3362 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3363 | ptid_build (ptid_get_pid (inferior_ptid), |
3364 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3365 | |
26cb8b7c | 3366 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3367 | lp->resumed = 1; |
3368 | } | |
3369 | ||
12696c10 | 3370 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3371 | block_child_signals (&prev_mask); |
d6b0e80f | 3372 | |
d6b0e80f | 3373 | /* First check if there is a LWP with a wait status pending. */ |
8a99810d PA |
3374 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3375 | if (lp != NULL) | |
d6b0e80f AC |
3376 | { |
3377 | if (debug_linux_nat) | |
d6b0e80f AC |
3378 | fprintf_unfiltered (gdb_stdlog, |
3379 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3380 | status_to_str (lp->status), |
d6b0e80f | 3381 | target_pid_to_str (lp->ptid)); |
d6b0e80f AC |
3382 | } |
3383 | ||
d9d41e78 | 3384 | if (!target_is_async_p ()) |
b84876c2 PA |
3385 | { |
3386 | /* Causes SIGINT to be passed on to the attached process. */ | |
3387 | set_sigint_trap (); | |
b84876c2 | 3388 | } |
d6b0e80f | 3389 | |
9c02b525 PA |
3390 | /* But if we don't find a pending event, we'll have to wait. Always |
3391 | pull all events out of the kernel. We'll randomly select an | |
3392 | event LWP out of all that have events, to prevent starvation. */ | |
7feb7d06 | 3393 | |
d90e17a7 | 3394 | while (lp == NULL) |
d6b0e80f AC |
3395 | { |
3396 | pid_t lwpid; | |
3397 | ||
0e5bf2a8 PA |
3398 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3399 | quirks: | |
3400 | ||
3401 | - If the thread group leader exits while other threads in the | |
3402 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3403 | waitpid won't return an exit status until the other threads | |
3404 | in the group are reapped. | |
3405 | ||
3406 | - When a non-leader thread execs, that thread just vanishes | |
3407 | without reporting an exit (so we'd hang if we waited for it | |
3408 | explicitly in that case). The exec event is reported to | |
3409 | the TGID pid. */ | |
3410 | ||
3411 | errno = 0; | |
3412 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3413 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3414 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3415 | ||
3416 | if (debug_linux_nat) | |
3417 | fprintf_unfiltered (gdb_stdlog, | |
3418 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3419 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3420 | |
d6b0e80f AC |
3421 | if (lwpid > 0) |
3422 | { | |
d6b0e80f AC |
3423 | if (debug_linux_nat) |
3424 | { | |
3425 | fprintf_unfiltered (gdb_stdlog, | |
3426 | "LLW: waitpid %ld received %s\n", | |
3427 | (long) lwpid, status_to_str (status)); | |
3428 | } | |
3429 | ||
9c02b525 | 3430 | linux_nat_filter_event (lwpid, status); |
0e5bf2a8 PA |
3431 | /* Retry until nothing comes out of waitpid. A single |
3432 | SIGCHLD can indicate more than one child stopped. */ | |
3433 | continue; | |
d6b0e80f AC |
3434 | } |
3435 | ||
20ba1ce6 PA |
3436 | /* Now that we've pulled all events out of the kernel, resume |
3437 | LWPs that don't have an interesting event to report. */ | |
3438 | iterate_over_lwps (minus_one_ptid, | |
3439 | resume_stopped_resumed_lwps, &minus_one_ptid); | |
3440 | ||
3441 | /* ... and find an LWP with a status to report to the core, if | |
3442 | any. */ | |
9c02b525 PA |
3443 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
3444 | if (lp != NULL) | |
3445 | break; | |
3446 | ||
0e5bf2a8 PA |
3447 | /* Check for zombie thread group leaders. Those can't be reaped |
3448 | until all other threads in the thread group are. */ | |
3449 | check_zombie_leaders (); | |
d6b0e80f | 3450 | |
0e5bf2a8 PA |
3451 | /* If there are no resumed children left, bail. We'd be stuck |
3452 | forever in the sigsuspend call below otherwise. */ | |
3453 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3454 | { | |
3455 | if (debug_linux_nat) | |
3456 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3457 | |
0e5bf2a8 | 3458 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3459 | |
d9d41e78 | 3460 | if (!target_is_async_p ()) |
0e5bf2a8 | 3461 | clear_sigint_trap (); |
b84876c2 | 3462 | |
0e5bf2a8 PA |
3463 | restore_child_signals_mask (&prev_mask); |
3464 | return minus_one_ptid; | |
d6b0e80f | 3465 | } |
28736962 | 3466 | |
0e5bf2a8 PA |
3467 | /* No interesting event to report to the core. */ |
3468 | ||
3469 | if (target_options & TARGET_WNOHANG) | |
3470 | { | |
01124a23 | 3471 | if (debug_linux_nat) |
28736962 PA |
3472 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3473 | ||
0e5bf2a8 | 3474 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3475 | restore_child_signals_mask (&prev_mask); |
3476 | return minus_one_ptid; | |
3477 | } | |
d6b0e80f AC |
3478 | |
3479 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3480 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3481 | |
3482 | /* Block until we get an event reported with SIGCHLD. */ | |
d36bf488 DE |
3483 | if (debug_linux_nat) |
3484 | fprintf_unfiltered (gdb_stdlog, "LNW: about to sigsuspend\n"); | |
0e5bf2a8 | 3485 | sigsuspend (&suspend_mask); |
d6b0e80f AC |
3486 | } |
3487 | ||
d9d41e78 | 3488 | if (!target_is_async_p ()) |
d26b5354 | 3489 | clear_sigint_trap (); |
d6b0e80f AC |
3490 | |
3491 | gdb_assert (lp); | |
3492 | ||
ca2163eb PA |
3493 | status = lp->status; |
3494 | lp->status = 0; | |
3495 | ||
4c28f408 PA |
3496 | if (!non_stop) |
3497 | { | |
3498 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3499 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3500 | |
3501 | /* ... and wait until all of them have reported back that | |
3502 | they're no longer running. */ | |
d90e17a7 | 3503 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
9c02b525 PA |
3504 | } |
3505 | ||
3506 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
3507 | among those that have had events. Giving equal priority to all | |
3508 | LWPs that have had events helps prevent starvation. */ | |
3509 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) | |
3510 | select_event_lwp (ptid, &lp, &status); | |
3511 | ||
3512 | gdb_assert (lp != NULL); | |
3513 | ||
3514 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
faf09f01 PA |
3515 | it was a software breakpoint, and we can't reliably support the |
3516 | "stopped by software breakpoint" stop reason. */ | |
3517 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3518 | && !USE_SIGTRAP_SIGINFO) | |
9c02b525 PA |
3519 | { |
3520 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
3521 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
527a273a | 3522 | int decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
4c28f408 | 3523 | |
9c02b525 PA |
3524 | if (decr_pc != 0) |
3525 | { | |
3526 | CORE_ADDR pc; | |
d6b0e80f | 3527 | |
9c02b525 PA |
3528 | pc = regcache_read_pc (regcache); |
3529 | regcache_write_pc (regcache, pc + decr_pc); | |
3530 | } | |
3531 | } | |
e3e9f5a2 | 3532 | |
9c02b525 PA |
3533 | /* We'll need this to determine whether to report a SIGSTOP as |
3534 | GDB_SIGNAL_0. Need to take a copy because resume_clear_callback | |
3535 | clears it. */ | |
3536 | last_resume_kind = lp->last_resume_kind; | |
4b60df3d | 3537 | |
9c02b525 PA |
3538 | if (!non_stop) |
3539 | { | |
e3e9f5a2 PA |
3540 | /* In all-stop, from the core's perspective, all LWPs are now |
3541 | stopped until a new resume action is sent over. */ | |
3542 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3543 | } | |
3544 | else | |
25289eb2 | 3545 | { |
4b60df3d | 3546 | resume_clear_callback (lp, NULL); |
25289eb2 | 3547 | } |
d6b0e80f | 3548 | |
26ab7092 | 3549 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3550 | { |
d6b0e80f AC |
3551 | if (debug_linux_nat) |
3552 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3553 | "LLW: trap ptid is %s.\n", |
3554 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3555 | } |
d6b0e80f AC |
3556 | |
3557 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3558 | { | |
3559 | *ourstatus = lp->waitstatus; | |
3560 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3561 | } | |
3562 | else | |
3563 | store_waitstatus (ourstatus, status); | |
3564 | ||
01124a23 | 3565 | if (debug_linux_nat) |
b84876c2 PA |
3566 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3567 | ||
7feb7d06 | 3568 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3569 | |
4b60df3d | 3570 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3571 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3572 | && WSTOPSIG (status) == SIGSTOP) | |
3573 | { | |
3574 | /* A thread that has been requested to stop by GDB with | |
3575 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3576 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3577 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3578 | } |
3579 | ||
1e225492 JK |
3580 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3581 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3582 | lp->core = -1; | |
3583 | else | |
2e794194 | 3584 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3585 | |
f973ed9c | 3586 | return lp->ptid; |
d6b0e80f AC |
3587 | } |
3588 | ||
e3e9f5a2 PA |
3589 | /* Resume LWPs that are currently stopped without any pending status |
3590 | to report, but are resumed from the core's perspective. */ | |
3591 | ||
3592 | static int | |
3593 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3594 | { | |
3595 | ptid_t *wait_ptid_p = data; | |
3596 | ||
3597 | if (lp->stopped | |
3598 | && lp->resumed | |
8a99810d | 3599 | && !lwp_status_pending_p (lp)) |
e3e9f5a2 | 3600 | { |
336060f3 PA |
3601 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3602 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
336060f3 | 3603 | |
23f238d3 | 3604 | TRY |
e3e9f5a2 | 3605 | { |
23f238d3 PA |
3606 | CORE_ADDR pc = regcache_read_pc (regcache); |
3607 | int leave_stopped = 0; | |
e3e9f5a2 | 3608 | |
23f238d3 PA |
3609 | /* Don't bother if there's a breakpoint at PC that we'd hit |
3610 | immediately, and we're not waiting for this LWP. */ | |
3611 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3612 | { | |
3613 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) | |
3614 | leave_stopped = 1; | |
3615 | } | |
e3e9f5a2 | 3616 | |
23f238d3 PA |
3617 | if (!leave_stopped) |
3618 | { | |
3619 | if (debug_linux_nat) | |
3620 | fprintf_unfiltered (gdb_stdlog, | |
3621 | "RSRL: resuming stopped-resumed LWP %s at " | |
3622 | "%s: step=%d\n", | |
3623 | target_pid_to_str (lp->ptid), | |
3624 | paddress (gdbarch, pc), | |
3625 | lp->step); | |
3626 | ||
3627 | linux_resume_one_lwp_throw (lp, lp->step, GDB_SIGNAL_0); | |
3628 | } | |
3629 | } | |
3630 | CATCH (ex, RETURN_MASK_ERROR) | |
3631 | { | |
3632 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
3633 | throw_exception (ex); | |
3634 | } | |
3635 | END_CATCH | |
e3e9f5a2 PA |
3636 | } |
3637 | ||
3638 | return 0; | |
3639 | } | |
3640 | ||
7feb7d06 PA |
3641 | static ptid_t |
3642 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3643 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3644 | int target_options) | |
7feb7d06 PA |
3645 | { |
3646 | ptid_t event_ptid; | |
3647 | ||
3648 | if (debug_linux_nat) | |
09826ec5 PA |
3649 | { |
3650 | char *options_string; | |
3651 | ||
3652 | options_string = target_options_to_string (target_options); | |
3653 | fprintf_unfiltered (gdb_stdlog, | |
3654 | "linux_nat_wait: [%s], [%s]\n", | |
3655 | target_pid_to_str (ptid), | |
3656 | options_string); | |
3657 | xfree (options_string); | |
3658 | } | |
7feb7d06 PA |
3659 | |
3660 | /* Flush the async file first. */ | |
d9d41e78 | 3661 | if (target_is_async_p ()) |
7feb7d06 PA |
3662 | async_file_flush (); |
3663 | ||
e3e9f5a2 PA |
3664 | /* Resume LWPs that are currently stopped without any pending status |
3665 | to report, but are resumed from the core's perspective. LWPs get | |
3666 | in this state if we find them stopping at a time we're not | |
3667 | interested in reporting the event (target_wait on a | |
3668 | specific_process, for example, see linux_nat_wait_1), and | |
3669 | meanwhile the event became uninteresting. Don't bother resuming | |
3670 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3671 | if (non_stop) | |
3672 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3673 | ||
47608cb1 | 3674 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3675 | |
3676 | /* If we requested any event, and something came out, assume there | |
3677 | may be more. If we requested a specific lwp or process, also | |
3678 | assume there may be more. */ | |
d9d41e78 | 3679 | if (target_is_async_p () |
6953d224 PA |
3680 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3681 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3682 | || !ptid_equal (ptid, minus_one_ptid))) |
3683 | async_file_mark (); | |
3684 | ||
7feb7d06 PA |
3685 | return event_ptid; |
3686 | } | |
3687 | ||
d6b0e80f AC |
3688 | static int |
3689 | kill_callback (struct lwp_info *lp, void *data) | |
3690 | { | |
ed731959 JK |
3691 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3692 | ||
3693 | errno = 0; | |
69ff6be5 | 3694 | kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 | 3695 | if (debug_linux_nat) |
57745c90 PA |
3696 | { |
3697 | int save_errno = errno; | |
3698 | ||
3699 | fprintf_unfiltered (gdb_stdlog, | |
3700 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3701 | target_pid_to_str (lp->ptid), | |
3702 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3703 | } | |
ed731959 JK |
3704 | |
3705 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3706 | ||
d6b0e80f | 3707 | errno = 0; |
dfd4cc63 | 3708 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f | 3709 | if (debug_linux_nat) |
57745c90 PA |
3710 | { |
3711 | int save_errno = errno; | |
3712 | ||
3713 | fprintf_unfiltered (gdb_stdlog, | |
3714 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3715 | target_pid_to_str (lp->ptid), | |
3716 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3717 | } | |
d6b0e80f AC |
3718 | |
3719 | return 0; | |
3720 | } | |
3721 | ||
3722 | static int | |
3723 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3724 | { | |
3725 | pid_t pid; | |
3726 | ||
3727 | /* We must make sure that there are no pending events (delayed | |
3728 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3729 | program doesn't interfere with any following debugging session. */ | |
3730 | ||
3731 | /* For cloned processes we must check both with __WCLONE and | |
3732 | without, since the exit status of a cloned process isn't reported | |
3733 | with __WCLONE. */ | |
3734 | if (lp->cloned) | |
3735 | { | |
3736 | do | |
3737 | { | |
dfd4cc63 | 3738 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3739 | if (pid != (pid_t) -1) |
d6b0e80f | 3740 | { |
e85a822c DJ |
3741 | if (debug_linux_nat) |
3742 | fprintf_unfiltered (gdb_stdlog, | |
3743 | "KWC: wait %s received unknown.\n", | |
3744 | target_pid_to_str (lp->ptid)); | |
3745 | /* The Linux kernel sometimes fails to kill a thread | |
3746 | completely after PTRACE_KILL; that goes from the stop | |
3747 | point in do_fork out to the one in | |
3748 | get_signal_to_deliever and waits again. So kill it | |
3749 | again. */ | |
3750 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3751 | } |
3752 | } | |
dfd4cc63 | 3753 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3754 | |
3755 | gdb_assert (pid == -1 && errno == ECHILD); | |
3756 | } | |
3757 | ||
3758 | do | |
3759 | { | |
dfd4cc63 | 3760 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3761 | if (pid != (pid_t) -1) |
d6b0e80f | 3762 | { |
e85a822c DJ |
3763 | if (debug_linux_nat) |
3764 | fprintf_unfiltered (gdb_stdlog, | |
3765 | "KWC: wait %s received unk.\n", | |
3766 | target_pid_to_str (lp->ptid)); | |
3767 | /* See the call to kill_callback above. */ | |
3768 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3769 | } |
3770 | } | |
dfd4cc63 | 3771 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3772 | |
3773 | gdb_assert (pid == -1 && errno == ECHILD); | |
3774 | return 0; | |
3775 | } | |
3776 | ||
3777 | static void | |
7d85a9c0 | 3778 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3779 | { |
f973ed9c DJ |
3780 | struct target_waitstatus last; |
3781 | ptid_t last_ptid; | |
3782 | int status; | |
d6b0e80f | 3783 | |
f973ed9c DJ |
3784 | /* If we're stopped while forking and we haven't followed yet, |
3785 | kill the other task. We need to do this first because the | |
3786 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3787 | |
f973ed9c | 3788 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3789 | |
f973ed9c DJ |
3790 | if (last.kind == TARGET_WAITKIND_FORKED |
3791 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3792 | { | |
dfd4cc63 | 3793 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3794 | wait (&status); |
26cb8b7c PA |
3795 | |
3796 | /* Let the arch-specific native code know this process is | |
3797 | gone. */ | |
dfd4cc63 | 3798 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3799 | } |
3800 | ||
3801 | if (forks_exist_p ()) | |
7feb7d06 | 3802 | linux_fork_killall (); |
f973ed9c DJ |
3803 | else |
3804 | { | |
d90e17a7 | 3805 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3806 | |
4c28f408 PA |
3807 | /* Stop all threads before killing them, since ptrace requires |
3808 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3809 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3810 | /* ... and wait until all of them have reported back that |
3811 | they're no longer running. */ | |
d90e17a7 | 3812 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3813 | |
f973ed9c | 3814 | /* Kill all LWP's ... */ |
d90e17a7 | 3815 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3816 | |
3817 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3818 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3819 | } |
3820 | ||
3821 | target_mourn_inferior (); | |
d6b0e80f AC |
3822 | } |
3823 | ||
3824 | static void | |
136d6dae | 3825 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3826 | { |
26cb8b7c PA |
3827 | int pid = ptid_get_pid (inferior_ptid); |
3828 | ||
3829 | purge_lwp_list (pid); | |
d6b0e80f | 3830 | |
f973ed9c | 3831 | if (! forks_exist_p ()) |
d90e17a7 PA |
3832 | /* Normal case, no other forks available. */ |
3833 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3834 | else |
3835 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3836 | there are other viable forks to debug. Delete the exiting | |
3837 | one and context-switch to the first available. */ | |
3838 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3839 | |
3840 | /* Let the arch-specific native code know this process is gone. */ | |
3841 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3842 | } |
3843 | ||
5b009018 PA |
3844 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3845 | layout of the inferiors' architecture. */ | |
3846 | ||
3847 | static void | |
a5362b9a | 3848 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3849 | { |
3850 | int done = 0; | |
3851 | ||
3852 | if (linux_nat_siginfo_fixup != NULL) | |
3853 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3854 | ||
3855 | /* If there was no callback, or the callback didn't do anything, | |
3856 | then just do a straight memcpy. */ | |
3857 | if (!done) | |
3858 | { | |
3859 | if (direction == 1) | |
a5362b9a | 3860 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3861 | else |
a5362b9a | 3862 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3863 | } |
3864 | } | |
3865 | ||
9b409511 | 3866 | static enum target_xfer_status |
4aa995e1 PA |
3867 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3868 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3869 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3870 | ULONGEST *xfered_len) | |
4aa995e1 | 3871 | { |
4aa995e1 | 3872 | int pid; |
a5362b9a TS |
3873 | siginfo_t siginfo; |
3874 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3875 | |
3876 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3877 | gdb_assert (readbuf || writebuf); | |
3878 | ||
dfd4cc63 | 3879 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3880 | if (pid == 0) |
dfd4cc63 | 3881 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3882 | |
3883 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3884 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3885 | |
3886 | errno = 0; | |
3887 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3888 | if (errno != 0) | |
2ed4b548 | 3889 | return TARGET_XFER_E_IO; |
4aa995e1 | 3890 | |
5b009018 PA |
3891 | /* When GDB is built as a 64-bit application, ptrace writes into |
3892 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3893 | inferior with a 64-bit GDB should look the same as debugging it | |
3894 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3895 | the converted layout, so any read/write will have to be done | |
3896 | post-conversion. */ | |
3897 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3898 | ||
4aa995e1 PA |
3899 | if (offset + len > sizeof (siginfo)) |
3900 | len = sizeof (siginfo) - offset; | |
3901 | ||
3902 | if (readbuf != NULL) | |
5b009018 | 3903 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3904 | else |
3905 | { | |
5b009018 PA |
3906 | memcpy (inf_siginfo + offset, writebuf, len); |
3907 | ||
3908 | /* Convert back to ptrace layout before flushing it out. */ | |
3909 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3910 | ||
4aa995e1 PA |
3911 | errno = 0; |
3912 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3913 | if (errno != 0) | |
2ed4b548 | 3914 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3915 | } |
3916 | ||
9b409511 YQ |
3917 | *xfered_len = len; |
3918 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3919 | } |
3920 | ||
9b409511 | 3921 | static enum target_xfer_status |
10d6c8cd DJ |
3922 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3923 | const char *annex, gdb_byte *readbuf, | |
3924 | const gdb_byte *writebuf, | |
9b409511 | 3925 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3926 | { |
4aa995e1 | 3927 | struct cleanup *old_chain; |
9b409511 | 3928 | enum target_xfer_status xfer; |
d6b0e80f | 3929 | |
4aa995e1 PA |
3930 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3931 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3932 | offset, len, xfered_len); |
4aa995e1 | 3933 | |
c35b1492 PA |
3934 | /* The target is connected but no live inferior is selected. Pass |
3935 | this request down to a lower stratum (e.g., the executable | |
3936 | file). */ | |
3937 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 3938 | return TARGET_XFER_EOF; |
c35b1492 | 3939 | |
4aa995e1 PA |
3940 | old_chain = save_inferior_ptid (); |
3941 | ||
dfd4cc63 LM |
3942 | if (ptid_lwp_p (inferior_ptid)) |
3943 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3944 | |
10d6c8cd | 3945 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3946 | offset, len, xfered_len); |
d6b0e80f AC |
3947 | |
3948 | do_cleanups (old_chain); | |
3949 | return xfer; | |
3950 | } | |
3951 | ||
3952 | static int | |
28439f5e | 3953 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3954 | { |
8c6a60d1 | 3955 | int err, tmp_errno; |
4c28f408 | 3956 | |
dfd4cc63 | 3957 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3958 | |
4c28f408 PA |
3959 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3960 | running thread errors out claiming that the thread doesn't | |
3961 | exist. */ | |
dfd4cc63 | 3962 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3963 | tmp_errno = errno; |
d6b0e80f AC |
3964 | if (debug_linux_nat) |
3965 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3966 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3967 | target_pid_to_str (ptid), |
8c6a60d1 | 3968 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3969 | |
4c28f408 | 3970 | if (err != 0) |
d6b0e80f AC |
3971 | return 0; |
3972 | ||
3973 | return 1; | |
3974 | } | |
3975 | ||
28439f5e PA |
3976 | static int |
3977 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3978 | { | |
3979 | return linux_thread_alive (ptid); | |
3980 | } | |
3981 | ||
d6b0e80f | 3982 | static char * |
117de6a9 | 3983 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3984 | { |
3985 | static char buf[64]; | |
3986 | ||
dfd4cc63 LM |
3987 | if (ptid_lwp_p (ptid) |
3988 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
3989 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 3990 | { |
dfd4cc63 | 3991 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
3992 | return buf; |
3993 | } | |
3994 | ||
3995 | return normal_pid_to_str (ptid); | |
3996 | } | |
3997 | ||
4694da01 | 3998 | static char * |
503a628d | 3999 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 TT |
4000 | { |
4001 | int pid = ptid_get_pid (thr->ptid); | |
4002 | long lwp = ptid_get_lwp (thr->ptid); | |
4003 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4004 | char buf[sizeof (FORMAT) + 30]; | |
4005 | FILE *comm_file; | |
4006 | char *result = NULL; | |
4007 | ||
4008 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4009 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4010 | if (comm_file) |
4011 | { | |
4012 | /* Not exported by the kernel, so we define it here. */ | |
4013 | #define COMM_LEN 16 | |
4014 | static char line[COMM_LEN + 1]; | |
4015 | ||
4016 | if (fgets (line, sizeof (line), comm_file)) | |
4017 | { | |
4018 | char *nl = strchr (line, '\n'); | |
4019 | ||
4020 | if (nl) | |
4021 | *nl = '\0'; | |
4022 | if (*line != '\0') | |
4023 | result = line; | |
4024 | } | |
4025 | ||
4026 | fclose (comm_file); | |
4027 | } | |
4028 | ||
4029 | #undef COMM_LEN | |
4030 | #undef FORMAT | |
4031 | ||
4032 | return result; | |
4033 | } | |
4034 | ||
dba24537 AC |
4035 | /* Accepts an integer PID; Returns a string representing a file that |
4036 | can be opened to get the symbols for the child process. */ | |
4037 | ||
6d8fd2b7 | 4038 | static char * |
8dd27370 | 4039 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 4040 | { |
b4ab256d HZ |
4041 | static char buf[PATH_MAX]; |
4042 | char name[PATH_MAX]; | |
dba24537 | 4043 | |
b4ab256d HZ |
4044 | xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid); |
4045 | memset (buf, 0, PATH_MAX); | |
4046 | if (readlink (name, buf, PATH_MAX - 1) <= 0) | |
4047 | strcpy (buf, name); | |
dba24537 | 4048 | |
b4ab256d | 4049 | return buf; |
dba24537 AC |
4050 | } |
4051 | ||
10d6c8cd DJ |
4052 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4053 | filesystem. Because we can use a single read() call for /proc, this | |
4054 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4055 | but it doesn't support writes. */ | |
4056 | ||
9b409511 | 4057 | static enum target_xfer_status |
10d6c8cd DJ |
4058 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
4059 | const char *annex, gdb_byte *readbuf, | |
4060 | const gdb_byte *writebuf, | |
9b409511 | 4061 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 4062 | { |
10d6c8cd DJ |
4063 | LONGEST ret; |
4064 | int fd; | |
dba24537 AC |
4065 | char filename[64]; |
4066 | ||
10d6c8cd | 4067 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4068 | return 0; |
4069 | ||
4070 | /* Don't bother for one word. */ | |
4071 | if (len < 3 * sizeof (long)) | |
9b409511 | 4072 | return TARGET_XFER_EOF; |
dba24537 AC |
4073 | |
4074 | /* We could keep this file open and cache it - possibly one per | |
4075 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4076 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4077 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4078 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 4079 | if (fd == -1) |
9b409511 | 4080 | return TARGET_XFER_EOF; |
dba24537 AC |
4081 | |
4082 | /* If pread64 is available, use it. It's faster if the kernel | |
4083 | supports it (only one syscall), and it's 64-bit safe even on | |
4084 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4085 | application). */ | |
4086 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4087 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4088 | #else |
10d6c8cd | 4089 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4090 | #endif |
4091 | ret = 0; | |
4092 | else | |
4093 | ret = len; | |
4094 | ||
4095 | close (fd); | |
9b409511 YQ |
4096 | |
4097 | if (ret == 0) | |
4098 | return TARGET_XFER_EOF; | |
4099 | else | |
4100 | { | |
4101 | *xfered_len = ret; | |
4102 | return TARGET_XFER_OK; | |
4103 | } | |
dba24537 AC |
4104 | } |
4105 | ||
efcbbd14 UW |
4106 | |
4107 | /* Enumerate spufs IDs for process PID. */ | |
4108 | static LONGEST | |
b55e14c7 | 4109 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4110 | { |
f5656ead | 4111 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4112 | LONGEST pos = 0; |
4113 | LONGEST written = 0; | |
4114 | char path[128]; | |
4115 | DIR *dir; | |
4116 | struct dirent *entry; | |
4117 | ||
4118 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4119 | dir = opendir (path); | |
4120 | if (!dir) | |
4121 | return -1; | |
4122 | ||
4123 | rewinddir (dir); | |
4124 | while ((entry = readdir (dir)) != NULL) | |
4125 | { | |
4126 | struct stat st; | |
4127 | struct statfs stfs; | |
4128 | int fd; | |
4129 | ||
4130 | fd = atoi (entry->d_name); | |
4131 | if (!fd) | |
4132 | continue; | |
4133 | ||
4134 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4135 | if (stat (path, &st) != 0) | |
4136 | continue; | |
4137 | if (!S_ISDIR (st.st_mode)) | |
4138 | continue; | |
4139 | ||
4140 | if (statfs (path, &stfs) != 0) | |
4141 | continue; | |
4142 | if (stfs.f_type != SPUFS_MAGIC) | |
4143 | continue; | |
4144 | ||
4145 | if (pos >= offset && pos + 4 <= offset + len) | |
4146 | { | |
4147 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4148 | written += 4; | |
4149 | } | |
4150 | pos += 4; | |
4151 | } | |
4152 | ||
4153 | closedir (dir); | |
4154 | return written; | |
4155 | } | |
4156 | ||
4157 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4158 | object type, using the /proc file system. */ | |
9b409511 YQ |
4159 | |
4160 | static enum target_xfer_status | |
efcbbd14 UW |
4161 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4162 | const char *annex, gdb_byte *readbuf, | |
4163 | const gdb_byte *writebuf, | |
9b409511 | 4164 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4165 | { |
4166 | char buf[128]; | |
4167 | int fd = 0; | |
4168 | int ret = -1; | |
dfd4cc63 | 4169 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4170 | |
4171 | if (!annex) | |
4172 | { | |
4173 | if (!readbuf) | |
2ed4b548 | 4174 | return TARGET_XFER_E_IO; |
efcbbd14 | 4175 | else |
9b409511 YQ |
4176 | { |
4177 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4178 | ||
4179 | if (l < 0) | |
4180 | return TARGET_XFER_E_IO; | |
4181 | else if (l == 0) | |
4182 | return TARGET_XFER_EOF; | |
4183 | else | |
4184 | { | |
4185 | *xfered_len = (ULONGEST) l; | |
4186 | return TARGET_XFER_OK; | |
4187 | } | |
4188 | } | |
efcbbd14 UW |
4189 | } |
4190 | ||
4191 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4192 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4193 | if (fd <= 0) |
2ed4b548 | 4194 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4195 | |
4196 | if (offset != 0 | |
4197 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4198 | { | |
4199 | close (fd); | |
9b409511 | 4200 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4201 | } |
4202 | ||
4203 | if (writebuf) | |
4204 | ret = write (fd, writebuf, (size_t) len); | |
4205 | else if (readbuf) | |
4206 | ret = read (fd, readbuf, (size_t) len); | |
4207 | ||
4208 | close (fd); | |
9b409511 YQ |
4209 | |
4210 | if (ret < 0) | |
4211 | return TARGET_XFER_E_IO; | |
4212 | else if (ret == 0) | |
4213 | return TARGET_XFER_EOF; | |
4214 | else | |
4215 | { | |
4216 | *xfered_len = (ULONGEST) ret; | |
4217 | return TARGET_XFER_OK; | |
4218 | } | |
efcbbd14 UW |
4219 | } |
4220 | ||
4221 | ||
dba24537 AC |
4222 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4223 | ||
4224 | static void | |
4225 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4226 | { | |
4227 | int len = strlen (line) - 1; | |
4228 | const char *p; | |
4229 | int signum; | |
4230 | ||
4231 | if (line[len] != '\n') | |
8a3fe4f8 | 4232 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4233 | |
4234 | p = line; | |
4235 | signum = len * 4; | |
4236 | while (len-- > 0) | |
4237 | { | |
4238 | int digit; | |
4239 | ||
4240 | if (*p >= '0' && *p <= '9') | |
4241 | digit = *p - '0'; | |
4242 | else if (*p >= 'a' && *p <= 'f') | |
4243 | digit = *p - 'a' + 10; | |
4244 | else | |
8a3fe4f8 | 4245 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4246 | |
4247 | signum -= 4; | |
4248 | ||
4249 | if (digit & 1) | |
4250 | sigaddset (sigs, signum + 1); | |
4251 | if (digit & 2) | |
4252 | sigaddset (sigs, signum + 2); | |
4253 | if (digit & 4) | |
4254 | sigaddset (sigs, signum + 3); | |
4255 | if (digit & 8) | |
4256 | sigaddset (sigs, signum + 4); | |
4257 | ||
4258 | p++; | |
4259 | } | |
4260 | } | |
4261 | ||
4262 | /* Find process PID's pending signals from /proc/pid/status and set | |
4263 | SIGS to match. */ | |
4264 | ||
4265 | void | |
3e43a32a MS |
4266 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4267 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4268 | { |
4269 | FILE *procfile; | |
d8d2a3ee | 4270 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4271 | struct cleanup *cleanup; |
dba24537 AC |
4272 | |
4273 | sigemptyset (pending); | |
4274 | sigemptyset (blocked); | |
4275 | sigemptyset (ignored); | |
cde33bf1 | 4276 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4277 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4278 | if (procfile == NULL) |
8a3fe4f8 | 4279 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4280 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4281 | |
d8d2a3ee | 4282 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4283 | { |
4284 | /* Normal queued signals are on the SigPnd line in the status | |
4285 | file. However, 2.6 kernels also have a "shared" pending | |
4286 | queue for delivering signals to a thread group, so check for | |
4287 | a ShdPnd line also. | |
4288 | ||
4289 | Unfortunately some Red Hat kernels include the shared pending | |
4290 | queue but not the ShdPnd status field. */ | |
4291 | ||
61012eef | 4292 | if (startswith (buffer, "SigPnd:\t")) |
dba24537 | 4293 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4294 | else if (startswith (buffer, "ShdPnd:\t")) |
dba24537 | 4295 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4296 | else if (startswith (buffer, "SigBlk:\t")) |
dba24537 | 4297 | add_line_to_sigset (buffer + 8, blocked); |
61012eef | 4298 | else if (startswith (buffer, "SigIgn:\t")) |
dba24537 AC |
4299 | add_line_to_sigset (buffer + 8, ignored); |
4300 | } | |
4301 | ||
7c8a8b04 | 4302 | do_cleanups (cleanup); |
dba24537 AC |
4303 | } |
4304 | ||
9b409511 | 4305 | static enum target_xfer_status |
07e059b5 | 4306 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4307 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4308 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4309 | ULONGEST *xfered_len) | |
07e059b5 | 4310 | { |
07e059b5 VP |
4311 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4312 | ||
9b409511 YQ |
4313 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4314 | if (*xfered_len == 0) | |
4315 | return TARGET_XFER_EOF; | |
4316 | else | |
4317 | return TARGET_XFER_OK; | |
07e059b5 VP |
4318 | } |
4319 | ||
9b409511 | 4320 | static enum target_xfer_status |
10d6c8cd DJ |
4321 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4322 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4323 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4324 | ULONGEST *xfered_len) | |
10d6c8cd | 4325 | { |
9b409511 | 4326 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4327 | |
4328 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4329 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4330 | offset, len, xfered_len); |
10d6c8cd | 4331 | |
07e059b5 VP |
4332 | if (object == TARGET_OBJECT_OSDATA) |
4333 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4334 | offset, len, xfered_len); |
07e059b5 | 4335 | |
efcbbd14 UW |
4336 | if (object == TARGET_OBJECT_SPU) |
4337 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4338 | offset, len, xfered_len); |
efcbbd14 | 4339 | |
8f313923 JK |
4340 | /* GDB calculates all the addresses in possibly larget width of the address. |
4341 | Address width needs to be masked before its final use - either by | |
4342 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4343 | ||
4344 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4345 | ||
4346 | if (object == TARGET_OBJECT_MEMORY) | |
4347 | { | |
f5656ead | 4348 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4349 | |
4350 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4351 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4352 | } | |
4353 | ||
10d6c8cd | 4354 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4355 | offset, len, xfered_len); |
4356 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4357 | return xfer; |
4358 | ||
4359 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4360 | offset, len, xfered_len); |
10d6c8cd DJ |
4361 | } |
4362 | ||
5808517f YQ |
4363 | static void |
4364 | cleanup_target_stop (void *arg) | |
4365 | { | |
4366 | ptid_t *ptid = (ptid_t *) arg; | |
4367 | ||
4368 | gdb_assert (arg != NULL); | |
4369 | ||
4370 | /* Unpause all */ | |
a493e3e2 | 4371 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4372 | } |
4373 | ||
4374 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4375 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4376 | const char *strid) | |
5808517f YQ |
4377 | { |
4378 | char s[IPA_CMD_BUF_SIZE]; | |
4379 | struct cleanup *old_chain; | |
4380 | int pid = ptid_get_pid (inferior_ptid); | |
4381 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4382 | struct static_tracepoint_marker *marker = NULL; | |
4383 | char *p = s; | |
4384 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4385 | ||
4386 | /* Pause all */ | |
4387 | target_stop (ptid); | |
4388 | ||
4389 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4390 | s[sizeof ("qTfSTM")] = 0; | |
4391 | ||
42476b70 | 4392 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4393 | |
4394 | old_chain = make_cleanup (free_current_marker, &marker); | |
4395 | make_cleanup (cleanup_target_stop, &ptid); | |
4396 | ||
4397 | while (*p++ == 'm') | |
4398 | { | |
4399 | if (marker == NULL) | |
4400 | marker = XCNEW (struct static_tracepoint_marker); | |
4401 | ||
4402 | do | |
4403 | { | |
4404 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4405 | ||
4406 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4407 | { | |
4408 | VEC_safe_push (static_tracepoint_marker_p, | |
4409 | markers, marker); | |
4410 | marker = NULL; | |
4411 | } | |
4412 | else | |
4413 | { | |
4414 | release_static_tracepoint_marker (marker); | |
4415 | memset (marker, 0, sizeof (*marker)); | |
4416 | } | |
4417 | } | |
4418 | while (*p++ == ','); /* comma-separated list */ | |
4419 | ||
4420 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4421 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4422 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4423 | p = s; |
4424 | } | |
4425 | ||
4426 | do_cleanups (old_chain); | |
4427 | ||
4428 | return markers; | |
4429 | } | |
4430 | ||
e9efe249 | 4431 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4432 | it with local methods. */ |
4433 | ||
910122bf UW |
4434 | static void |
4435 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4436 | { |
6d8fd2b7 | 4437 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4438 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4439 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4440 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4441 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4442 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4443 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4444 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4445 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4446 | t->to_post_attach = linux_child_post_attach; |
4447 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4448 | |
4449 | super_xfer_partial = t->to_xfer_partial; | |
4450 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4451 | |
4452 | t->to_static_tracepoint_markers_by_strid | |
4453 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4454 | } |
4455 | ||
4456 | struct target_ops * | |
4457 | linux_target (void) | |
4458 | { | |
4459 | struct target_ops *t; | |
4460 | ||
4461 | t = inf_ptrace_target (); | |
4462 | linux_target_install_ops (t); | |
4463 | ||
4464 | return t; | |
4465 | } | |
4466 | ||
4467 | struct target_ops * | |
7714d83a | 4468 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4469 | { |
4470 | struct target_ops *t; | |
4471 | ||
4472 | t = inf_ptrace_trad_target (register_u_offset); | |
4473 | linux_target_install_ops (t); | |
10d6c8cd | 4474 | |
10d6c8cd DJ |
4475 | return t; |
4476 | } | |
4477 | ||
b84876c2 PA |
4478 | /* target_is_async_p implementation. */ |
4479 | ||
4480 | static int | |
6a109b6b | 4481 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 | 4482 | { |
198297aa | 4483 | return linux_is_async_p (); |
b84876c2 PA |
4484 | } |
4485 | ||
4486 | /* target_can_async_p implementation. */ | |
4487 | ||
4488 | static int | |
6a109b6b | 4489 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4490 | { |
4491 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4492 | it explicitly with the "set target-async" command. |
b84876c2 | 4493 | Someday, linux will always be async. */ |
3dd5b83d | 4494 | return target_async_permitted; |
b84876c2 PA |
4495 | } |
4496 | ||
9908b566 | 4497 | static int |
2a9a2795 | 4498 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4499 | { |
4500 | return 1; | |
4501 | } | |
4502 | ||
d90e17a7 PA |
4503 | /* True if we want to support multi-process. To be removed when GDB |
4504 | supports multi-exec. */ | |
4505 | ||
2277426b | 4506 | int linux_multi_process = 1; |
d90e17a7 PA |
4507 | |
4508 | static int | |
86ce2668 | 4509 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4510 | { |
4511 | return linux_multi_process; | |
4512 | } | |
4513 | ||
03583c20 | 4514 | static int |
2bfc0540 | 4515 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4516 | { |
4517 | #ifdef HAVE_PERSONALITY | |
4518 | return 1; | |
4519 | #else | |
4520 | return 0; | |
4521 | #endif | |
4522 | } | |
4523 | ||
b84876c2 PA |
4524 | static int async_terminal_is_ours = 1; |
4525 | ||
4d4ca2a1 DE |
4526 | /* target_terminal_inferior implementation. |
4527 | ||
4528 | This is a wrapper around child_terminal_inferior to add async support. */ | |
b84876c2 PA |
4529 | |
4530 | static void | |
d2f640d4 | 4531 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 | 4532 | { |
198297aa PA |
4533 | /* Like target_terminal_inferior, use target_can_async_p, not |
4534 | target_is_async_p, since at this point the target is not async | |
4535 | yet. If it can async, then we know it will become async prior to | |
4536 | resume. */ | |
4537 | if (!target_can_async_p ()) | |
b84876c2 PA |
4538 | { |
4539 | /* Async mode is disabled. */ | |
d6b64346 | 4540 | child_terminal_inferior (self); |
b84876c2 PA |
4541 | return; |
4542 | } | |
4543 | ||
d6b64346 | 4544 | child_terminal_inferior (self); |
b84876c2 | 4545 | |
d9d2d8b6 | 4546 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4547 | if (!async_terminal_is_ours) |
4548 | return; | |
4549 | ||
4550 | delete_file_handler (input_fd); | |
4551 | async_terminal_is_ours = 0; | |
4552 | set_sigint_trap (); | |
4553 | } | |
4554 | ||
4d4ca2a1 DE |
4555 | /* target_terminal_ours implementation. |
4556 | ||
4557 | This is a wrapper around child_terminal_ours to add async support (and | |
4558 | implement the target_terminal_ours vs target_terminal_ours_for_output | |
4559 | distinction). child_terminal_ours is currently no different than | |
4560 | child_terminal_ours_for_output. | |
4561 | We leave target_terminal_ours_for_output alone, leaving it to | |
4562 | child_terminal_ours_for_output. */ | |
b84876c2 | 4563 | |
2c0b251b | 4564 | static void |
e3594fd1 | 4565 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 | 4566 | { |
b84876c2 PA |
4567 | /* GDB should never give the terminal to the inferior if the |
4568 | inferior is running in the background (run&, continue&, etc.), | |
4569 | but claiming it sure should. */ | |
d6b64346 | 4570 | child_terminal_ours (self); |
b84876c2 | 4571 | |
b84876c2 PA |
4572 | if (async_terminal_is_ours) |
4573 | return; | |
4574 | ||
4575 | clear_sigint_trap (); | |
4576 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4577 | async_terminal_is_ours = 1; | |
4578 | } | |
4579 | ||
4580 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4581 | void *context); | |
4582 | static void *async_client_context; | |
4583 | ||
7feb7d06 PA |
4584 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4585 | so we notice when any child changes state, and notify the | |
4586 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4587 | above to wait for the arrival of a SIGCHLD. */ | |
4588 | ||
b84876c2 | 4589 | static void |
7feb7d06 | 4590 | sigchld_handler (int signo) |
b84876c2 | 4591 | { |
7feb7d06 PA |
4592 | int old_errno = errno; |
4593 | ||
01124a23 DE |
4594 | if (debug_linux_nat) |
4595 | ui_file_write_async_safe (gdb_stdlog, | |
4596 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4597 | |
4598 | if (signo == SIGCHLD | |
4599 | && linux_nat_event_pipe[0] != -1) | |
4600 | async_file_mark (); /* Let the event loop know that there are | |
4601 | events to handle. */ | |
4602 | ||
4603 | errno = old_errno; | |
4604 | } | |
4605 | ||
4606 | /* Callback registered with the target events file descriptor. */ | |
4607 | ||
4608 | static void | |
4609 | handle_target_event (int error, gdb_client_data client_data) | |
4610 | { | |
4611 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4612 | } | |
4613 | ||
4614 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4615 | ||
4616 | static int | |
4617 | linux_async_pipe (int enable) | |
4618 | { | |
198297aa | 4619 | int previous = linux_is_async_p (); |
7feb7d06 PA |
4620 | |
4621 | if (previous != enable) | |
4622 | { | |
4623 | sigset_t prev_mask; | |
4624 | ||
12696c10 PA |
4625 | /* Block child signals while we create/destroy the pipe, as |
4626 | their handler writes to it. */ | |
7feb7d06 PA |
4627 | block_child_signals (&prev_mask); |
4628 | ||
4629 | if (enable) | |
4630 | { | |
614c279d | 4631 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4632 | internal_error (__FILE__, __LINE__, |
4633 | "creating event pipe failed."); | |
4634 | ||
4635 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4636 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4637 | } | |
4638 | else | |
4639 | { | |
4640 | close (linux_nat_event_pipe[0]); | |
4641 | close (linux_nat_event_pipe[1]); | |
4642 | linux_nat_event_pipe[0] = -1; | |
4643 | linux_nat_event_pipe[1] = -1; | |
4644 | } | |
4645 | ||
4646 | restore_child_signals_mask (&prev_mask); | |
4647 | } | |
4648 | ||
4649 | return previous; | |
b84876c2 PA |
4650 | } |
4651 | ||
4652 | /* target_async implementation. */ | |
4653 | ||
4654 | static void | |
6a109b6b TT |
4655 | linux_nat_async (struct target_ops *ops, |
4656 | void (*callback) (enum inferior_event_type event_type, | |
4657 | void *context), | |
4658 | void *context) | |
b84876c2 | 4659 | { |
b84876c2 PA |
4660 | if (callback != NULL) |
4661 | { | |
4662 | async_client_callback = callback; | |
4663 | async_client_context = context; | |
7feb7d06 PA |
4664 | if (!linux_async_pipe (1)) |
4665 | { | |
4666 | add_file_handler (linux_nat_event_pipe[0], | |
4667 | handle_target_event, NULL); | |
4668 | /* There may be pending events to handle. Tell the event loop | |
4669 | to poll them. */ | |
4670 | async_file_mark (); | |
4671 | } | |
b84876c2 PA |
4672 | } |
4673 | else | |
4674 | { | |
4675 | async_client_callback = callback; | |
4676 | async_client_context = context; | |
b84876c2 | 4677 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4678 | linux_async_pipe (0); |
b84876c2 PA |
4679 | } |
4680 | return; | |
4681 | } | |
4682 | ||
a493e3e2 | 4683 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4684 | event came out. */ |
4685 | ||
4c28f408 | 4686 | static int |
252fbfc8 | 4687 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4688 | { |
d90e17a7 | 4689 | if (!lwp->stopped) |
252fbfc8 | 4690 | { |
d90e17a7 PA |
4691 | if (debug_linux_nat) |
4692 | fprintf_unfiltered (gdb_stdlog, | |
4693 | "LNSL: running -> suspending %s\n", | |
4694 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4695 | |
252fbfc8 | 4696 | |
25289eb2 PA |
4697 | if (lwp->last_resume_kind == resume_stop) |
4698 | { | |
4699 | if (debug_linux_nat) | |
4700 | fprintf_unfiltered (gdb_stdlog, | |
4701 | "linux-nat: already stopping LWP %ld at " | |
4702 | "GDB's request\n", | |
4703 | ptid_get_lwp (lwp->ptid)); | |
4704 | return 0; | |
4705 | } | |
252fbfc8 | 4706 | |
25289eb2 PA |
4707 | stop_callback (lwp, NULL); |
4708 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4709 | } |
4710 | else | |
4711 | { | |
4712 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4713 | |
d90e17a7 PA |
4714 | if (debug_linux_nat) |
4715 | { | |
e09875d4 | 4716 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4717 | fprintf_unfiltered (gdb_stdlog, |
4718 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4719 | target_pid_to_str (lwp->ptid)); |
4720 | else | |
3e43a32a MS |
4721 | fprintf_unfiltered (gdb_stdlog, |
4722 | "LNSL: already stopped/no " | |
4723 | "stop_requested yet %s\n", | |
d90e17a7 | 4724 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4725 | } |
4726 | } | |
4c28f408 PA |
4727 | return 0; |
4728 | } | |
4729 | ||
4730 | static void | |
1eab8a48 | 4731 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 PA |
4732 | { |
4733 | if (non_stop) | |
d90e17a7 | 4734 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4735 | else |
1eab8a48 | 4736 | linux_ops->to_stop (linux_ops, ptid); |
4c28f408 PA |
4737 | } |
4738 | ||
d90e17a7 | 4739 | static void |
de90e03d | 4740 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4741 | { |
4742 | /* Unregister from the event loop. */ | |
9debeba0 DE |
4743 | if (linux_nat_is_async_p (self)) |
4744 | linux_nat_async (self, NULL, NULL); | |
d90e17a7 | 4745 | |
d90e17a7 | 4746 | if (linux_ops->to_close) |
de90e03d | 4747 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4748 | |
4749 | super_close (self); | |
d90e17a7 PA |
4750 | } |
4751 | ||
c0694254 PA |
4752 | /* When requests are passed down from the linux-nat layer to the |
4753 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4754 | used. The address space pointer is stored in the inferior object, | |
4755 | but the common code that is passed such ptid can't tell whether | |
4756 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4757 | look up the "main" process id from the lwp here. */ | |
4758 | ||
70221824 | 4759 | static struct address_space * |
c0694254 PA |
4760 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4761 | { | |
4762 | struct lwp_info *lwp; | |
4763 | struct inferior *inf; | |
4764 | int pid; | |
4765 | ||
dfd4cc63 | 4766 | if (ptid_get_lwp (ptid) == 0) |
c0694254 PA |
4767 | { |
4768 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4769 | tgid. */ | |
4770 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4771 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4772 | } |
4773 | else | |
4774 | { | |
4775 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4776 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4777 | } |
4778 | ||
4779 | inf = find_inferior_pid (pid); | |
4780 | gdb_assert (inf != NULL); | |
4781 | return inf->aspace; | |
4782 | } | |
4783 | ||
dc146f7c VP |
4784 | /* Return the cached value of the processor core for thread PTID. */ |
4785 | ||
70221824 | 4786 | static int |
dc146f7c VP |
4787 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4788 | { | |
4789 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4790 | |
dc146f7c VP |
4791 | if (info) |
4792 | return info->core; | |
4793 | return -1; | |
4794 | } | |
4795 | ||
f973ed9c DJ |
4796 | void |
4797 | linux_nat_add_target (struct target_ops *t) | |
4798 | { | |
f973ed9c DJ |
4799 | /* Save the provided single-threaded target. We save this in a separate |
4800 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4801 | may have saved a pointer to T; we want to use it for the final | |
4802 | process stratum target. */ | |
4803 | linux_ops_saved = *t; | |
4804 | linux_ops = &linux_ops_saved; | |
4805 | ||
4806 | /* Override some methods for multithreading. */ | |
b84876c2 | 4807 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4808 | t->to_attach = linux_nat_attach; |
4809 | t->to_detach = linux_nat_detach; | |
4810 | t->to_resume = linux_nat_resume; | |
4811 | t->to_wait = linux_nat_wait; | |
2455069d | 4812 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4813 | t->to_xfer_partial = linux_nat_xfer_partial; |
4814 | t->to_kill = linux_nat_kill; | |
4815 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4816 | t->to_thread_alive = linux_nat_thread_alive; | |
4817 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4818 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4819 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4820 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4821 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4822 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
faf09f01 PA |
4823 | t->to_stopped_by_sw_breakpoint = linux_nat_stopped_by_sw_breakpoint; |
4824 | t->to_supports_stopped_by_sw_breakpoint = linux_nat_supports_stopped_by_sw_breakpoint; | |
4825 | t->to_stopped_by_hw_breakpoint = linux_nat_stopped_by_hw_breakpoint; | |
4826 | t->to_supports_stopped_by_hw_breakpoint = linux_nat_supports_stopped_by_hw_breakpoint; | |
f973ed9c | 4827 | |
b84876c2 PA |
4828 | t->to_can_async_p = linux_nat_can_async_p; |
4829 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4830 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4831 | t->to_async = linux_nat_async; |
b84876c2 PA |
4832 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4833 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4834 | |
4835 | super_close = t->to_close; | |
d90e17a7 | 4836 | t->to_close = linux_nat_close; |
b84876c2 | 4837 | |
4c28f408 PA |
4838 | /* Methods for non-stop support. */ |
4839 | t->to_stop = linux_nat_stop; | |
4840 | ||
d90e17a7 PA |
4841 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4842 | ||
03583c20 UW |
4843 | t->to_supports_disable_randomization |
4844 | = linux_nat_supports_disable_randomization; | |
4845 | ||
dc146f7c VP |
4846 | t->to_core_of_thread = linux_nat_core_of_thread; |
4847 | ||
f973ed9c DJ |
4848 | /* We don't change the stratum; this target will sit at |
4849 | process_stratum and thread_db will set at thread_stratum. This | |
4850 | is a little strange, since this is a multi-threaded-capable | |
4851 | target, but we want to be on the stack below thread_db, and we | |
4852 | also want to be used for single-threaded processes. */ | |
4853 | ||
4854 | add_target (t); | |
f973ed9c DJ |
4855 | } |
4856 | ||
9f0bdab8 DJ |
4857 | /* Register a method to call whenever a new thread is attached. */ |
4858 | void | |
7b50312a PA |
4859 | linux_nat_set_new_thread (struct target_ops *t, |
4860 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4861 | { |
4862 | /* Save the pointer. We only support a single registered instance | |
4863 | of the GNU/Linux native target, so we do not need to map this to | |
4864 | T. */ | |
4865 | linux_nat_new_thread = new_thread; | |
4866 | } | |
4867 | ||
26cb8b7c PA |
4868 | /* See declaration in linux-nat.h. */ |
4869 | ||
4870 | void | |
4871 | linux_nat_set_new_fork (struct target_ops *t, | |
4872 | linux_nat_new_fork_ftype *new_fork) | |
4873 | { | |
4874 | /* Save the pointer. */ | |
4875 | linux_nat_new_fork = new_fork; | |
4876 | } | |
4877 | ||
4878 | /* See declaration in linux-nat.h. */ | |
4879 | ||
4880 | void | |
4881 | linux_nat_set_forget_process (struct target_ops *t, | |
4882 | linux_nat_forget_process_ftype *fn) | |
4883 | { | |
4884 | /* Save the pointer. */ | |
4885 | linux_nat_forget_process_hook = fn; | |
4886 | } | |
4887 | ||
4888 | /* See declaration in linux-nat.h. */ | |
4889 | ||
4890 | void | |
4891 | linux_nat_forget_process (pid_t pid) | |
4892 | { | |
4893 | if (linux_nat_forget_process_hook != NULL) | |
4894 | linux_nat_forget_process_hook (pid); | |
4895 | } | |
4896 | ||
5b009018 PA |
4897 | /* Register a method that converts a siginfo object between the layout |
4898 | that ptrace returns, and the layout in the architecture of the | |
4899 | inferior. */ | |
4900 | void | |
4901 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4902 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4903 | gdb_byte *, |
4904 | int)) | |
4905 | { | |
4906 | /* Save the pointer. */ | |
4907 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4908 | } | |
4909 | ||
7b50312a PA |
4910 | /* Register a method to call prior to resuming a thread. */ |
4911 | ||
4912 | void | |
4913 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4914 | void (*prepare_to_resume) (struct lwp_info *)) | |
4915 | { | |
4916 | /* Save the pointer. */ | |
4917 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4918 | } | |
4919 | ||
f865ee35 JK |
4920 | /* See linux-nat.h. */ |
4921 | ||
4922 | int | |
4923 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4924 | { |
da559b09 | 4925 | int pid; |
9f0bdab8 | 4926 | |
dfd4cc63 | 4927 | pid = ptid_get_lwp (ptid); |
da559b09 | 4928 | if (pid == 0) |
dfd4cc63 | 4929 | pid = ptid_get_pid (ptid); |
f865ee35 | 4930 | |
da559b09 JK |
4931 | errno = 0; |
4932 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4933 | if (errno != 0) | |
4934 | { | |
4935 | memset (siginfo, 0, sizeof (*siginfo)); | |
4936 | return 0; | |
4937 | } | |
f865ee35 | 4938 | return 1; |
9f0bdab8 DJ |
4939 | } |
4940 | ||
7b669087 GB |
4941 | /* See nat/linux-nat.h. */ |
4942 | ||
4943 | ptid_t | |
4944 | current_lwp_ptid (void) | |
4945 | { | |
4946 | gdb_assert (ptid_lwp_p (inferior_ptid)); | |
4947 | return inferior_ptid; | |
4948 | } | |
4949 | ||
2c0b251b PA |
4950 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4951 | extern initialize_file_ftype _initialize_linux_nat; | |
4952 | ||
d6b0e80f AC |
4953 | void |
4954 | _initialize_linux_nat (void) | |
4955 | { | |
ccce17b0 YQ |
4956 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4957 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4958 | Set debugging of GNU/Linux lwp module."), _("\ |
4959 | Show debugging of GNU/Linux lwp module."), _("\ | |
4960 | Enables printf debugging output."), | |
ccce17b0 YQ |
4961 | NULL, |
4962 | show_debug_linux_nat, | |
4963 | &setdebuglist, &showdebuglist); | |
b84876c2 | 4964 | |
b84876c2 | 4965 | /* Save this mask as the default. */ |
d6b0e80f AC |
4966 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4967 | ||
7feb7d06 PA |
4968 | /* Install a SIGCHLD handler. */ |
4969 | sigchld_action.sa_handler = sigchld_handler; | |
4970 | sigemptyset (&sigchld_action.sa_mask); | |
4971 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
4972 | |
4973 | /* Make it the default. */ | |
7feb7d06 | 4974 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
4975 | |
4976 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4977 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4978 | sigdelset (&suspend_mask, SIGCHLD); | |
4979 | ||
7feb7d06 | 4980 | sigemptyset (&blocked_mask); |
8009206a TT |
4981 | |
4982 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to | |
4983 | support read-only process state. */ | |
4984 | linux_ptrace_set_additional_flags (PTRACE_O_TRACESYSGOOD | |
4985 | | PTRACE_O_TRACEVFORKDONE | |
4986 | | PTRACE_O_TRACEVFORK | |
4987 | | PTRACE_O_TRACEFORK | |
4988 | | PTRACE_O_TRACEEXEC); | |
d6b0e80f AC |
4989 | } |
4990 | \f | |
4991 | ||
4992 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4993 | the GNU/Linux Threads library and therefore doesn't really belong | |
4994 | here. */ | |
4995 | ||
4996 | /* Read variable NAME in the target and return its value if found. | |
4997 | Otherwise return zero. It is assumed that the type of the variable | |
4998 | is `int'. */ | |
4999 | ||
5000 | static int | |
5001 | get_signo (const char *name) | |
5002 | { | |
3b7344d5 | 5003 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5004 | int signo; |
5005 | ||
5006 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5007 | if (ms.minsym == NULL) |
d6b0e80f AC |
5008 | return 0; |
5009 | ||
77e371c0 | 5010 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5011 | sizeof (signo)) != 0) |
5012 | return 0; | |
5013 | ||
5014 | return signo; | |
5015 | } | |
5016 | ||
5017 | /* Return the set of signals used by the threads library in *SET. */ | |
5018 | ||
5019 | void | |
5020 | lin_thread_get_thread_signals (sigset_t *set) | |
5021 | { | |
5022 | struct sigaction action; | |
5023 | int restart, cancel; | |
5024 | ||
b84876c2 | 5025 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5026 | sigemptyset (set); |
5027 | ||
5028 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5029 | cancel = get_signo ("__pthread_sig_cancel"); |
5030 | ||
5031 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5032 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5033 | not provide any way for the debugger to query the signal numbers - | |
5034 | fortunately they don't change! */ | |
5035 | ||
d6b0e80f | 5036 | if (restart == 0) |
17fbb0bd | 5037 | restart = __SIGRTMIN; |
d6b0e80f | 5038 | |
d6b0e80f | 5039 | if (cancel == 0) |
17fbb0bd | 5040 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5041 | |
5042 | sigaddset (set, restart); | |
5043 | sigaddset (set, cancel); | |
5044 | ||
5045 | /* The GNU/Linux Threads library makes terminating threads send a | |
5046 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5047 | those (to prevent them from terminating GDB itself, which is | |
5048 | likely to be their default action) and treat them the same way as | |
5049 | SIGCHLD. */ | |
5050 | ||
5051 | action.sa_handler = sigchld_handler; | |
5052 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5053 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5054 | sigaction (cancel, &action, NULL); |
5055 | ||
5056 | /* We block the "cancel" signal throughout this code ... */ | |
5057 | sigaddset (&blocked_mask, cancel); | |
5058 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5059 | ||
5060 | /* ... except during a sigsuspend. */ | |
5061 | sigdelset (&suspend_mask, cancel); | |
5062 | } |