Commit | Line | Data |
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3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
ecd75fc8 | 3 | Copyright (C) 2001-2014 Free Software Foundation, Inc. |
3993f6b1 DJ |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
3993f6b1 DJ |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3993f6b1 DJ |
19 | |
20 | #include "defs.h" | |
21 | #include "inferior.h" | |
45741a9c | 22 | #include "infrun.h" |
3993f6b1 | 23 | #include "target.h" |
96d7229d LM |
24 | #include "nat/linux-nat.h" |
25 | #include "nat/linux-waitpid.h" | |
0e9f083f | 26 | #include <string.h> |
3993f6b1 | 27 | #include "gdb_wait.h" |
d6b0e80f AC |
28 | #ifdef HAVE_TKILL_SYSCALL |
29 | #include <unistd.h> | |
30 | #include <sys/syscall.h> | |
31 | #endif | |
3993f6b1 | 32 | #include <sys/ptrace.h> |
0274a8ce | 33 | #include "linux-nat.h" |
125f8a3d GB |
34 | #include "nat/linux-ptrace.h" |
35 | #include "nat/linux-procfs.h" | |
ac264b3b | 36 | #include "linux-fork.h" |
d6b0e80f AC |
37 | #include "gdbthread.h" |
38 | #include "gdbcmd.h" | |
39 | #include "regcache.h" | |
4f844a66 | 40 | #include "regset.h" |
dab06dbe | 41 | #include "inf-child.h" |
10d6c8cd DJ |
42 | #include "inf-ptrace.h" |
43 | #include "auxv.h" | |
1777feb0 | 44 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
45 | #include "elf-bfd.h" /* for elfcore_write_* */ |
46 | #include "gregset.h" /* for gregset */ | |
47 | #include "gdbcore.h" /* for get_exec_file */ | |
48 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 49 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 50 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
51 | #include "inf-loop.h" |
52 | #include "event-loop.h" | |
53 | #include "event-top.h" | |
07e059b5 VP |
54 | #include <pwd.h> |
55 | #include <sys/types.h> | |
2978b111 | 56 | #include <dirent.h> |
07e059b5 | 57 | #include "xml-support.h" |
191c4426 | 58 | #include "terminal.h" |
efcbbd14 | 59 | #include <sys/vfs.h> |
6c95b8df | 60 | #include "solib.h" |
125f8a3d | 61 | #include "nat/linux-osdata.h" |
6432734d | 62 | #include "linux-tdep.h" |
7dcd53a0 | 63 | #include "symfile.h" |
5808517f YQ |
64 | #include "agent.h" |
65 | #include "tracepoint.h" | |
87b0bb13 | 66 | #include "exceptions.h" |
87b0bb13 | 67 | #include "buffer.h" |
6ecd4729 | 68 | #include "target-descriptions.h" |
614c279d | 69 | #include "filestuff.h" |
77e371c0 | 70 | #include "objfiles.h" |
efcbbd14 UW |
71 | |
72 | #ifndef SPUFS_MAGIC | |
73 | #define SPUFS_MAGIC 0x23c9b64e | |
74 | #endif | |
dba24537 | 75 | |
10568435 JK |
76 | #ifdef HAVE_PERSONALITY |
77 | # include <sys/personality.h> | |
78 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
79 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
80 | # endif | |
81 | #endif /* HAVE_PERSONALITY */ | |
82 | ||
1777feb0 | 83 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
84 | |
85 | Waiting for events in sync mode | |
86 | =============================== | |
87 | ||
88 | When waiting for an event in a specific thread, we just use waitpid, passing | |
89 | the specific pid, and not passing WNOHANG. | |
90 | ||
1777feb0 | 91 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 92 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 93 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
94 | miss an event. The solution is to use non-blocking waitpid, together with |
95 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 96 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
97 | flag to check for events in cloned processes. If nothing is found, we use |
98 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
99 | happened to a child process -- and SIGCHLD will be delivered both for events | |
100 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
101 | an event, we get back to calling nonblocking waitpid with and without |
102 | __WCLONED. | |
8a77dff3 VP |
103 | |
104 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 105 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
106 | blocked, the signal becomes pending and sigsuspend immediately |
107 | notices it and returns. | |
108 | ||
109 | Waiting for events in async mode | |
110 | ================================ | |
111 | ||
7feb7d06 PA |
112 | In async mode, GDB should always be ready to handle both user input |
113 | and target events, so neither blocking waitpid nor sigsuspend are | |
114 | viable options. Instead, we should asynchronously notify the GDB main | |
115 | event loop whenever there's an unprocessed event from the target. We | |
116 | detect asynchronous target events by handling SIGCHLD signals. To | |
117 | notify the event loop about target events, the self-pipe trick is used | |
118 | --- a pipe is registered as waitable event source in the event loop, | |
119 | the event loop select/poll's on the read end of this pipe (as well on | |
120 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
121 | byte to this pipe. This is more portable than relying on | |
122 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
123 | emulates them with select/poll+sigprocmask, and that is racy | |
124 | (a.k.a. plain broken). | |
125 | ||
126 | Obviously, if we fail to notify the event loop if there's a target | |
127 | event, it's bad. OTOH, if we notify the event loop when there's no | |
128 | event from the target, linux_nat_wait will detect that there's no real | |
129 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
130 | This is mostly harmless, but it will waste time and is better avoided. | |
131 | ||
132 | The main design point is that every time GDB is outside linux-nat.c, | |
133 | we have a SIGCHLD handler installed that is called when something | |
134 | happens to the target and notifies the GDB event loop. Whenever GDB | |
135 | core decides to handle the event, and calls into linux-nat.c, we | |
136 | process things as in sync mode, except that the we never block in | |
137 | sigsuspend. | |
138 | ||
139 | While processing an event, we may end up momentarily blocked in | |
140 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
141 | return quickly. E.g., in all-stop mode, before reporting to the core | |
142 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
143 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
144 | Note that this is different from blocking indefinitely waiting for the | |
145 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
146 | |
147 | Use of signals | |
148 | ============== | |
149 | ||
150 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
151 | signal is not entirely significant; we just need for a signal to be delivered, | |
152 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
153 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
154 | be queued once; we do not keep track of other sources of SIGSTOP. | |
155 | ||
156 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
157 | use them, because they have special behavior when the signal is generated - | |
158 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
159 | kills the entire thread group. | |
160 | ||
161 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
162 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
163 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
164 | ||
165 | We could use a real-time signal instead. This would solve those problems; we | |
166 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
167 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
168 | generates it, and there are races with trying to find a signal that is not | |
169 | blocked. */ | |
a0ef4274 | 170 | |
dba24537 AC |
171 | #ifndef O_LARGEFILE |
172 | #define O_LARGEFILE 0 | |
173 | #endif | |
0274a8ce | 174 | |
10d6c8cd DJ |
175 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
176 | the use of the multi-threaded target. */ | |
177 | static struct target_ops *linux_ops; | |
f973ed9c | 178 | static struct target_ops linux_ops_saved; |
10d6c8cd | 179 | |
9f0bdab8 | 180 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
181 | static void (*linux_nat_new_thread) (struct lwp_info *); |
182 | ||
26cb8b7c PA |
183 | /* The method to call, if any, when a new fork is attached. */ |
184 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
185 | ||
186 | /* The method to call, if any, when a process is no longer | |
187 | attached. */ | |
188 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
189 | ||
7b50312a PA |
190 | /* Hook to call prior to resuming a thread. */ |
191 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 192 | |
5b009018 PA |
193 | /* The method to call, if any, when the siginfo object needs to be |
194 | converted between the layout returned by ptrace, and the layout in | |
195 | the architecture of the inferior. */ | |
a5362b9a | 196 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
197 | gdb_byte *, |
198 | int); | |
199 | ||
ac264b3b MS |
200 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
201 | Called by our to_xfer_partial. */ | |
4ac248ca | 202 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 203 | |
6a3cb8e8 PA |
204 | /* The saved to_close method, inherited from inf-ptrace.c. |
205 | Called by our to_close. */ | |
206 | static void (*super_close) (struct target_ops *); | |
207 | ||
ccce17b0 | 208 | static unsigned int debug_linux_nat; |
920d2a44 AC |
209 | static void |
210 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
211 | struct cmd_list_element *c, const char *value) | |
212 | { | |
213 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
214 | value); | |
215 | } | |
d6b0e80f | 216 | |
ae087d01 DJ |
217 | struct simple_pid_list |
218 | { | |
219 | int pid; | |
3d799a95 | 220 | int status; |
ae087d01 DJ |
221 | struct simple_pid_list *next; |
222 | }; | |
223 | struct simple_pid_list *stopped_pids; | |
224 | ||
3dd5b83d PA |
225 | /* Async mode support. */ |
226 | ||
b84876c2 PA |
227 | /* The read/write ends of the pipe registered as waitable file in the |
228 | event loop. */ | |
229 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
230 | ||
7feb7d06 | 231 | /* Flush the event pipe. */ |
b84876c2 | 232 | |
7feb7d06 PA |
233 | static void |
234 | async_file_flush (void) | |
b84876c2 | 235 | { |
7feb7d06 PA |
236 | int ret; |
237 | char buf; | |
b84876c2 | 238 | |
7feb7d06 | 239 | do |
b84876c2 | 240 | { |
7feb7d06 | 241 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 242 | } |
7feb7d06 | 243 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
244 | } |
245 | ||
7feb7d06 PA |
246 | /* Put something (anything, doesn't matter what, or how much) in event |
247 | pipe, so that the select/poll in the event-loop realizes we have | |
248 | something to process. */ | |
252fbfc8 | 249 | |
b84876c2 | 250 | static void |
7feb7d06 | 251 | async_file_mark (void) |
b84876c2 | 252 | { |
7feb7d06 | 253 | int ret; |
b84876c2 | 254 | |
7feb7d06 PA |
255 | /* It doesn't really matter what the pipe contains, as long we end |
256 | up with something in it. Might as well flush the previous | |
257 | left-overs. */ | |
258 | async_file_flush (); | |
b84876c2 | 259 | |
7feb7d06 | 260 | do |
b84876c2 | 261 | { |
7feb7d06 | 262 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 263 | } |
7feb7d06 | 264 | while (ret == -1 && errno == EINTR); |
b84876c2 | 265 | |
7feb7d06 PA |
266 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
267 | be awakened anyway. */ | |
b84876c2 PA |
268 | } |
269 | ||
7feb7d06 PA |
270 | static int kill_lwp (int lwpid, int signo); |
271 | ||
272 | static int stop_callback (struct lwp_info *lp, void *data); | |
273 | ||
274 | static void block_child_signals (sigset_t *prev_mask); | |
275 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
276 | |
277 | struct lwp_info; | |
278 | static struct lwp_info *add_lwp (ptid_t ptid); | |
279 | static void purge_lwp_list (int pid); | |
4403d8e9 | 280 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
281 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
282 | ||
ae087d01 DJ |
283 | \f |
284 | /* Trivial list manipulation functions to keep track of a list of | |
285 | new stopped processes. */ | |
286 | static void | |
3d799a95 | 287 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
288 | { |
289 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 290 | |
ae087d01 | 291 | new_pid->pid = pid; |
3d799a95 | 292 | new_pid->status = status; |
ae087d01 DJ |
293 | new_pid->next = *listp; |
294 | *listp = new_pid; | |
295 | } | |
296 | ||
84636d28 PA |
297 | static int |
298 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
299 | { | |
300 | struct simple_pid_list *p; | |
301 | ||
302 | for (p = list; p != NULL; p = p->next) | |
303 | if (p->pid == pid) | |
304 | return 1; | |
305 | return 0; | |
306 | } | |
307 | ||
ae087d01 | 308 | static int |
46a96992 | 309 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
310 | { |
311 | struct simple_pid_list **p; | |
312 | ||
313 | for (p = listp; *p != NULL; p = &(*p)->next) | |
314 | if ((*p)->pid == pid) | |
315 | { | |
316 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 317 | |
46a96992 | 318 | *statusp = (*p)->status; |
ae087d01 DJ |
319 | xfree (*p); |
320 | *p = next; | |
321 | return 1; | |
322 | } | |
323 | return 0; | |
324 | } | |
325 | ||
96d7229d LM |
326 | /* Initialize ptrace warnings and check for supported ptrace |
327 | features given PID. */ | |
3993f6b1 DJ |
328 | |
329 | static void | |
96d7229d | 330 | linux_init_ptrace (pid_t pid) |
3993f6b1 | 331 | { |
96d7229d LM |
332 | linux_enable_event_reporting (pid); |
333 | linux_ptrace_init_warnings (); | |
4de4c07c DJ |
334 | } |
335 | ||
6d8fd2b7 | 336 | static void |
f045800c | 337 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 338 | { |
96d7229d | 339 | linux_init_ptrace (pid); |
4de4c07c DJ |
340 | } |
341 | ||
10d6c8cd | 342 | static void |
2e97a79e | 343 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 344 | { |
96d7229d | 345 | linux_init_ptrace (ptid_get_pid (ptid)); |
4de4c07c DJ |
346 | } |
347 | ||
4403d8e9 JK |
348 | /* Return the number of known LWPs in the tgid given by PID. */ |
349 | ||
350 | static int | |
351 | num_lwps (int pid) | |
352 | { | |
353 | int count = 0; | |
354 | struct lwp_info *lp; | |
355 | ||
356 | for (lp = lwp_list; lp; lp = lp->next) | |
357 | if (ptid_get_pid (lp->ptid) == pid) | |
358 | count++; | |
359 | ||
360 | return count; | |
361 | } | |
362 | ||
363 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
364 | ||
365 | static void | |
366 | delete_lwp_cleanup (void *lp_voidp) | |
367 | { | |
368 | struct lwp_info *lp = lp_voidp; | |
369 | ||
370 | delete_lwp (lp->ptid); | |
371 | } | |
372 | ||
6d8fd2b7 | 373 | static int |
07107ca6 LM |
374 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
375 | int detach_fork) | |
3993f6b1 | 376 | { |
9016a515 | 377 | int has_vforked; |
4de4c07c DJ |
378 | int parent_pid, child_pid; |
379 | ||
e58b0e63 PA |
380 | has_vforked = (inferior_thread ()->pending_follow.kind |
381 | == TARGET_WAITKIND_VFORKED); | |
382 | parent_pid = ptid_get_lwp (inferior_ptid); | |
d3587048 | 383 | if (parent_pid == 0) |
e58b0e63 | 384 | parent_pid = ptid_get_pid (inferior_ptid); |
dfd4cc63 LM |
385 | child_pid |
386 | = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid); | |
4de4c07c | 387 | |
6c95b8df PA |
388 | if (has_vforked |
389 | && !non_stop /* Non-stop always resumes both branches. */ | |
390 | && (!target_is_async_p () || sync_execution) | |
391 | && !(follow_child || detach_fork || sched_multi)) | |
392 | { | |
393 | /* The parent stays blocked inside the vfork syscall until the | |
394 | child execs or exits. If we don't let the child run, then | |
395 | the parent stays blocked. If we're telling the parent to run | |
396 | in the foreground, the user will not be able to ctrl-c to get | |
397 | back the terminal, effectively hanging the debug session. */ | |
ac74f770 MS |
398 | fprintf_filtered (gdb_stderr, _("\ |
399 | Can not resume the parent process over vfork in the foreground while\n\ | |
400 | holding the child stopped. Try \"set detach-on-fork\" or \ | |
401 | \"set schedule-multiple\".\n")); | |
402 | /* FIXME output string > 80 columns. */ | |
6c95b8df PA |
403 | return 1; |
404 | } | |
405 | ||
4de4c07c DJ |
406 | if (! follow_child) |
407 | { | |
6c95b8df | 408 | struct lwp_info *child_lp = NULL; |
4de4c07c | 409 | |
1777feb0 | 410 | /* We're already attached to the parent, by default. */ |
4de4c07c | 411 | |
ac264b3b MS |
412 | /* Detach new forked process? */ |
413 | if (detach_fork) | |
f75c00e4 | 414 | { |
4403d8e9 | 415 | struct cleanup *old_chain; |
9caaaa83 | 416 | int status = W_STOPCODE (0); |
4403d8e9 | 417 | |
6c95b8df PA |
418 | /* Before detaching from the child, remove all breakpoints |
419 | from it. If we forked, then this has already been taken | |
420 | care of by infrun.c. If we vforked however, any | |
421 | breakpoint inserted in the parent is visible in the | |
422 | child, even those added while stopped in a vfork | |
423 | catchpoint. This will remove the breakpoints from the | |
424 | parent also, but they'll be reinserted below. */ | |
425 | if (has_vforked) | |
426 | { | |
427 | /* keep breakpoints list in sync. */ | |
dfd4cc63 | 428 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
6c95b8df PA |
429 | } |
430 | ||
e85a822c | 431 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
432 | { |
433 | target_terminal_ours (); | |
434 | fprintf_filtered (gdb_stdlog, | |
3e43a32a MS |
435 | "Detaching after fork from " |
436 | "child process %d.\n", | |
ac264b3b MS |
437 | child_pid); |
438 | } | |
4de4c07c | 439 | |
4403d8e9 JK |
440 | old_chain = save_inferior_ptid (); |
441 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
442 | ||
443 | child_lp = add_lwp (inferior_ptid); | |
444 | child_lp->stopped = 1; | |
445 | child_lp->last_resume_kind = resume_stop; | |
446 | make_cleanup (delete_lwp_cleanup, child_lp); | |
447 | ||
4403d8e9 JK |
448 | if (linux_nat_prepare_to_resume != NULL) |
449 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
450 | |
451 | /* When debugging an inferior in an architecture that supports | |
452 | hardware single stepping on a kernel without commit | |
453 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
454 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
455 | set if the parent process had them set. | |
456 | To work around this, single step the child process | |
457 | once before detaching to clear the flags. */ | |
458 | ||
459 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
460 | (child_lp->ptid))) | |
461 | { | |
c077881a HZ |
462 | linux_disable_event_reporting (child_pid); |
463 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
464 | perror_with_name (_("Couldn't do single step")); | |
465 | if (my_waitpid (child_pid, &status, 0) < 0) | |
466 | perror_with_name (_("Couldn't wait vfork process")); | |
467 | } | |
468 | ||
469 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
470 | { |
471 | int signo; | |
472 | ||
473 | signo = WSTOPSIG (status); | |
474 | if (signo != 0 | |
475 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
476 | signo = 0; | |
477 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
478 | } | |
4403d8e9 JK |
479 | |
480 | do_cleanups (old_chain); | |
ac264b3b MS |
481 | } |
482 | else | |
483 | { | |
77435e4c | 484 | struct inferior *parent_inf, *child_inf; |
2277426b | 485 | struct cleanup *old_chain; |
7f9f62ba PA |
486 | |
487 | /* Add process to GDB's tables. */ | |
77435e4c PA |
488 | child_inf = add_inferior (child_pid); |
489 | ||
e58b0e63 | 490 | parent_inf = current_inferior (); |
77435e4c | 491 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 492 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
493 | child_inf->gdbarch = parent_inf->gdbarch; |
494 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7f9f62ba | 495 | |
2277426b | 496 | old_chain = save_inferior_ptid (); |
6c95b8df | 497 | save_current_program_space (); |
2277426b PA |
498 | |
499 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
500 | add_thread (inferior_ptid); | |
6c95b8df PA |
501 | child_lp = add_lwp (inferior_ptid); |
502 | child_lp->stopped = 1; | |
25289eb2 | 503 | child_lp->last_resume_kind = resume_stop; |
7dcd53a0 | 504 | child_inf->symfile_flags = SYMFILE_NO_READ; |
2277426b | 505 | |
6c95b8df PA |
506 | /* If this is a vfork child, then the address-space is |
507 | shared with the parent. */ | |
508 | if (has_vforked) | |
509 | { | |
510 | child_inf->pspace = parent_inf->pspace; | |
511 | child_inf->aspace = parent_inf->aspace; | |
512 | ||
513 | /* The parent will be frozen until the child is done | |
514 | with the shared region. Keep track of the | |
515 | parent. */ | |
516 | child_inf->vfork_parent = parent_inf; | |
517 | child_inf->pending_detach = 0; | |
518 | parent_inf->vfork_child = child_inf; | |
519 | parent_inf->pending_detach = 0; | |
520 | } | |
521 | else | |
522 | { | |
523 | child_inf->aspace = new_address_space (); | |
524 | child_inf->pspace = add_program_space (child_inf->aspace); | |
525 | child_inf->removable = 1; | |
526 | set_current_program_space (child_inf->pspace); | |
527 | clone_program_space (child_inf->pspace, parent_inf->pspace); | |
528 | ||
529 | /* Let the shared library layer (solib-svr4) learn about | |
530 | this new process, relocate the cloned exec, pull in | |
531 | shared libraries, and install the solib event | |
532 | breakpoint. If a "cloned-VM" event was propagated | |
533 | better throughout the core, this wouldn't be | |
534 | required. */ | |
268a4a75 | 535 | solib_create_inferior_hook (0); |
6c95b8df PA |
536 | } |
537 | ||
538 | /* Let the thread_db layer learn about this new process. */ | |
2277426b PA |
539 | check_for_thread_db (); |
540 | ||
541 | do_cleanups (old_chain); | |
ac264b3b | 542 | } |
9016a515 DJ |
543 | |
544 | if (has_vforked) | |
545 | { | |
3ced3da4 | 546 | struct lwp_info *parent_lp; |
6c95b8df PA |
547 | struct inferior *parent_inf; |
548 | ||
549 | parent_inf = current_inferior (); | |
550 | ||
551 | /* If we detached from the child, then we have to be careful | |
552 | to not insert breakpoints in the parent until the child | |
553 | is done with the shared memory region. However, if we're | |
554 | staying attached to the child, then we can and should | |
555 | insert breakpoints, so that we can debug it. A | |
556 | subsequent child exec or exit is enough to know when does | |
557 | the child stops using the parent's address space. */ | |
558 | parent_inf->waiting_for_vfork_done = detach_fork; | |
56710373 | 559 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
6c95b8df | 560 | |
3ced3da4 | 561 | parent_lp = find_lwp_pid (pid_to_ptid (parent_pid)); |
96d7229d | 562 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 563 | |
96d7229d | 564 | if (linux_supports_tracevforkdone ()) |
9016a515 | 565 | { |
6c95b8df PA |
566 | if (debug_linux_nat) |
567 | fprintf_unfiltered (gdb_stdlog, | |
568 | "LCFF: waiting for VFORK_DONE on %d\n", | |
569 | parent_pid); | |
3ced3da4 | 570 | parent_lp->stopped = 1; |
9016a515 | 571 | |
6c95b8df PA |
572 | /* We'll handle the VFORK_DONE event like any other |
573 | event, in target_wait. */ | |
9016a515 DJ |
574 | } |
575 | else | |
576 | { | |
577 | /* We can't insert breakpoints until the child has | |
578 | finished with the shared memory region. We need to | |
579 | wait until that happens. Ideal would be to just | |
580 | call: | |
581 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
582 | - waitpid (parent_pid, &status, __WALL); | |
583 | However, most architectures can't handle a syscall | |
584 | being traced on the way out if it wasn't traced on | |
585 | the way in. | |
586 | ||
587 | We might also think to loop, continuing the child | |
588 | until it exits or gets a SIGTRAP. One problem is | |
589 | that the child might call ptrace with PTRACE_TRACEME. | |
590 | ||
591 | There's no simple and reliable way to figure out when | |
592 | the vforked child will be done with its copy of the | |
593 | shared memory. We could step it out of the syscall, | |
594 | two instructions, let it go, and then single-step the | |
595 | parent once. When we have hardware single-step, this | |
596 | would work; with software single-step it could still | |
597 | be made to work but we'd have to be able to insert | |
598 | single-step breakpoints in the child, and we'd have | |
599 | to insert -just- the single-step breakpoint in the | |
600 | parent. Very awkward. | |
601 | ||
602 | In the end, the best we can do is to make sure it | |
603 | runs for a little while. Hopefully it will be out of | |
604 | range of any breakpoints we reinsert. Usually this | |
605 | is only the single-step breakpoint at vfork's return | |
606 | point. */ | |
607 | ||
6c95b8df PA |
608 | if (debug_linux_nat) |
609 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
610 | "LCFF: no VFORK_DONE " |
611 | "support, sleeping a bit\n"); | |
6c95b8df | 612 | |
9016a515 | 613 | usleep (10000); |
9016a515 | 614 | |
6c95b8df PA |
615 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
616 | and leave it pending. The next linux_nat_resume call | |
617 | will notice a pending event, and bypasses actually | |
618 | resuming the inferior. */ | |
3ced3da4 PA |
619 | parent_lp->status = 0; |
620 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
621 | parent_lp->stopped = 1; | |
6c95b8df PA |
622 | |
623 | /* If we're in async mode, need to tell the event loop | |
624 | there's something here to process. */ | |
625 | if (target_can_async_p ()) | |
626 | async_file_mark (); | |
627 | } | |
9016a515 | 628 | } |
4de4c07c | 629 | } |
3993f6b1 | 630 | else |
4de4c07c | 631 | { |
77435e4c | 632 | struct inferior *parent_inf, *child_inf; |
3ced3da4 | 633 | struct lwp_info *child_lp; |
6c95b8df | 634 | struct program_space *parent_pspace; |
4de4c07c | 635 | |
e85a822c | 636 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
637 | { |
638 | target_terminal_ours (); | |
6c95b8df | 639 | if (has_vforked) |
3e43a32a MS |
640 | fprintf_filtered (gdb_stdlog, |
641 | _("Attaching after process %d " | |
642 | "vfork to child process %d.\n"), | |
6c95b8df PA |
643 | parent_pid, child_pid); |
644 | else | |
3e43a32a MS |
645 | fprintf_filtered (gdb_stdlog, |
646 | _("Attaching after process %d " | |
647 | "fork to child process %d.\n"), | |
6c95b8df | 648 | parent_pid, child_pid); |
f75c00e4 | 649 | } |
4de4c07c | 650 | |
7a7d3353 PA |
651 | /* Add the new inferior first, so that the target_detach below |
652 | doesn't unpush the target. */ | |
653 | ||
77435e4c PA |
654 | child_inf = add_inferior (child_pid); |
655 | ||
e58b0e63 | 656 | parent_inf = current_inferior (); |
77435e4c | 657 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 658 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
659 | child_inf->gdbarch = parent_inf->gdbarch; |
660 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7a7d3353 | 661 | |
6c95b8df | 662 | parent_pspace = parent_inf->pspace; |
9016a515 | 663 | |
6c95b8df PA |
664 | /* If we're vforking, we want to hold on to the parent until the |
665 | child exits or execs. At child exec or exit time we can | |
666 | remove the old breakpoints from the parent and detach or | |
667 | resume debugging it. Otherwise, detach the parent now; we'll | |
668 | want to reuse it's program/address spaces, but we can't set | |
669 | them to the child before removing breakpoints from the | |
670 | parent, otherwise, the breakpoints module could decide to | |
671 | remove breakpoints from the wrong process (since they'd be | |
672 | assigned to the same address space). */ | |
9016a515 DJ |
673 | |
674 | if (has_vforked) | |
7f9f62ba | 675 | { |
6c95b8df PA |
676 | gdb_assert (child_inf->vfork_parent == NULL); |
677 | gdb_assert (parent_inf->vfork_child == NULL); | |
678 | child_inf->vfork_parent = parent_inf; | |
679 | child_inf->pending_detach = 0; | |
680 | parent_inf->vfork_child = child_inf; | |
681 | parent_inf->pending_detach = detach_fork; | |
682 | parent_inf->waiting_for_vfork_done = 0; | |
ac264b3b | 683 | } |
2277426b | 684 | else if (detach_fork) |
b84876c2 | 685 | target_detach (NULL, 0); |
4de4c07c | 686 | |
6c95b8df PA |
687 | /* Note that the detach above makes PARENT_INF dangling. */ |
688 | ||
689 | /* Add the child thread to the appropriate lists, and switch to | |
690 | this new thread, before cloning the program space, and | |
691 | informing the solib layer about this new process. */ | |
692 | ||
9f0bdab8 | 693 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
2277426b | 694 | add_thread (inferior_ptid); |
3ced3da4 PA |
695 | child_lp = add_lwp (inferior_ptid); |
696 | child_lp->stopped = 1; | |
25289eb2 | 697 | child_lp->last_resume_kind = resume_stop; |
6c95b8df PA |
698 | |
699 | /* If this is a vfork child, then the address-space is shared | |
700 | with the parent. If we detached from the parent, then we can | |
701 | reuse the parent's program/address spaces. */ | |
702 | if (has_vforked || detach_fork) | |
703 | { | |
704 | child_inf->pspace = parent_pspace; | |
705 | child_inf->aspace = child_inf->pspace->aspace; | |
706 | } | |
707 | else | |
708 | { | |
709 | child_inf->aspace = new_address_space (); | |
710 | child_inf->pspace = add_program_space (child_inf->aspace); | |
711 | child_inf->removable = 1; | |
7dcd53a0 | 712 | child_inf->symfile_flags = SYMFILE_NO_READ; |
6c95b8df PA |
713 | set_current_program_space (child_inf->pspace); |
714 | clone_program_space (child_inf->pspace, parent_pspace); | |
715 | ||
716 | /* Let the shared library layer (solib-svr4) learn about | |
717 | this new process, relocate the cloned exec, pull in | |
718 | shared libraries, and install the solib event breakpoint. | |
719 | If a "cloned-VM" event was propagated better throughout | |
720 | the core, this wouldn't be required. */ | |
268a4a75 | 721 | solib_create_inferior_hook (0); |
6c95b8df | 722 | } |
ac264b3b | 723 | |
6c95b8df | 724 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 725 | check_for_thread_db (); |
4de4c07c DJ |
726 | } |
727 | ||
728 | return 0; | |
729 | } | |
730 | ||
4de4c07c | 731 | \f |
77b06cd7 | 732 | static int |
a863b201 | 733 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 734 | { |
96d7229d | 735 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
736 | } |
737 | ||
eb73ad13 | 738 | static int |
973fc227 | 739 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
740 | { |
741 | return 0; | |
742 | } | |
743 | ||
77b06cd7 | 744 | static int |
3ecc7da0 | 745 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 746 | { |
96d7229d | 747 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
748 | } |
749 | ||
eb73ad13 | 750 | static int |
e98cf0cd | 751 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
752 | { |
753 | return 0; | |
754 | } | |
755 | ||
77b06cd7 | 756 | static int |
ba025e51 | 757 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 758 | { |
96d7229d | 759 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
760 | } |
761 | ||
eb73ad13 | 762 | static int |
758e29d2 | 763 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
764 | { |
765 | return 0; | |
766 | } | |
767 | ||
a96d9b2e | 768 | static int |
ff214e67 TT |
769 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
770 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
771 | int table_size, int *table) |
772 | { | |
96d7229d | 773 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
774 | return 1; |
775 | ||
a96d9b2e SDJ |
776 | /* On GNU/Linux, we ignore the arguments. It means that we only |
777 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 778 | |
a96d9b2e SDJ |
779 | Also, we do not use the `table' information because we do not |
780 | filter system calls here. We let GDB do the logic for us. */ | |
781 | return 0; | |
782 | } | |
783 | ||
d6b0e80f AC |
784 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
785 | are processes sharing the same VM space. A multi-threaded process | |
786 | is basically a group of such processes. However, such a grouping | |
787 | is almost entirely a user-space issue; the kernel doesn't enforce | |
788 | such a grouping at all (this might change in the future). In | |
789 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
790 | Threads library) to provide such a grouping. | |
791 | ||
792 | It is perfectly well possible to write a multi-threaded application | |
793 | without the assistance of a threads library, by using the clone | |
794 | system call directly. This module should be able to give some | |
795 | rudimentary support for debugging such applications if developers | |
796 | specify the CLONE_PTRACE flag in the clone system call, and are | |
797 | using the Linux kernel 2.4 or above. | |
798 | ||
799 | Note that there are some peculiarities in GNU/Linux that affect | |
800 | this code: | |
801 | ||
802 | - In general one should specify the __WCLONE flag to waitpid in | |
803 | order to make it report events for any of the cloned processes | |
804 | (and leave it out for the initial process). However, if a cloned | |
805 | process has exited the exit status is only reported if the | |
806 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
807 | we cannot use it since GDB must work on older systems too. | |
808 | ||
809 | - When a traced, cloned process exits and is waited for by the | |
810 | debugger, the kernel reassigns it to the original parent and | |
811 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
812 | library doesn't notice this, which leads to the "zombie problem": | |
813 | When debugged a multi-threaded process that spawns a lot of | |
814 | threads will run out of processes, even if the threads exit, | |
815 | because the "zombies" stay around. */ | |
816 | ||
817 | /* List of known LWPs. */ | |
9f0bdab8 | 818 | struct lwp_info *lwp_list; |
d6b0e80f AC |
819 | \f |
820 | ||
d6b0e80f AC |
821 | /* Original signal mask. */ |
822 | static sigset_t normal_mask; | |
823 | ||
824 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
825 | _initialize_linux_nat. */ | |
826 | static sigset_t suspend_mask; | |
827 | ||
7feb7d06 PA |
828 | /* Signals to block to make that sigsuspend work. */ |
829 | static sigset_t blocked_mask; | |
830 | ||
831 | /* SIGCHLD action. */ | |
832 | struct sigaction sigchld_action; | |
b84876c2 | 833 | |
7feb7d06 PA |
834 | /* Block child signals (SIGCHLD and linux threads signals), and store |
835 | the previous mask in PREV_MASK. */ | |
84e46146 | 836 | |
7feb7d06 PA |
837 | static void |
838 | block_child_signals (sigset_t *prev_mask) | |
839 | { | |
840 | /* Make sure SIGCHLD is blocked. */ | |
841 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
842 | sigaddset (&blocked_mask, SIGCHLD); | |
843 | ||
844 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
845 | } | |
846 | ||
847 | /* Restore child signals mask, previously returned by | |
848 | block_child_signals. */ | |
849 | ||
850 | static void | |
851 | restore_child_signals_mask (sigset_t *prev_mask) | |
852 | { | |
853 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
854 | } | |
2455069d UW |
855 | |
856 | /* Mask of signals to pass directly to the inferior. */ | |
857 | static sigset_t pass_mask; | |
858 | ||
859 | /* Update signals to pass to the inferior. */ | |
860 | static void | |
94bedb42 TT |
861 | linux_nat_pass_signals (struct target_ops *self, |
862 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
863 | { |
864 | int signo; | |
865 | ||
866 | sigemptyset (&pass_mask); | |
867 | ||
868 | for (signo = 1; signo < NSIG; signo++) | |
869 | { | |
2ea28649 | 870 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
871 | if (target_signo < numsigs && pass_signals[target_signo]) |
872 | sigaddset (&pass_mask, signo); | |
873 | } | |
874 | } | |
875 | ||
d6b0e80f AC |
876 | \f |
877 | ||
878 | /* Prototypes for local functions. */ | |
879 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 880 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 881 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
710151dd | 882 | |
d6b0e80f | 883 | \f |
d6b0e80f | 884 | |
7b50312a PA |
885 | /* Destroy and free LP. */ |
886 | ||
887 | static void | |
888 | lwp_free (struct lwp_info *lp) | |
889 | { | |
890 | xfree (lp->arch_private); | |
891 | xfree (lp); | |
892 | } | |
893 | ||
d90e17a7 PA |
894 | /* Remove all LWPs belong to PID from the lwp list. */ |
895 | ||
896 | static void | |
897 | purge_lwp_list (int pid) | |
898 | { | |
899 | struct lwp_info *lp, *lpprev, *lpnext; | |
900 | ||
901 | lpprev = NULL; | |
902 | ||
903 | for (lp = lwp_list; lp; lp = lpnext) | |
904 | { | |
905 | lpnext = lp->next; | |
906 | ||
907 | if (ptid_get_pid (lp->ptid) == pid) | |
908 | { | |
909 | if (lp == lwp_list) | |
910 | lwp_list = lp->next; | |
911 | else | |
912 | lpprev->next = lp->next; | |
913 | ||
7b50312a | 914 | lwp_free (lp); |
d90e17a7 PA |
915 | } |
916 | else | |
917 | lpprev = lp; | |
918 | } | |
919 | } | |
920 | ||
26cb8b7c PA |
921 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
922 | in the process. Return a pointer to the structure describing the | |
923 | new LWP. | |
924 | ||
925 | This differs from add_lwp in that we don't let the arch specific | |
926 | bits know about this new thread. Current clients of this callback | |
927 | take the opportunity to install watchpoints in the new thread, and | |
928 | we shouldn't do that for the first thread. If we're spawning a | |
929 | child ("run"), the thread executes the shell wrapper first, and we | |
930 | shouldn't touch it until it execs the program we want to debug. | |
931 | For "attach", it'd be okay to call the callback, but it's not | |
932 | necessary, because watchpoints can't yet have been inserted into | |
933 | the inferior. */ | |
d6b0e80f AC |
934 | |
935 | static struct lwp_info * | |
26cb8b7c | 936 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
937 | { |
938 | struct lwp_info *lp; | |
939 | ||
dfd4cc63 | 940 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
941 | |
942 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
943 | ||
944 | memset (lp, 0, sizeof (struct lwp_info)); | |
945 | ||
25289eb2 | 946 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
947 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
948 | ||
949 | lp->ptid = ptid; | |
dc146f7c | 950 | lp->core = -1; |
d6b0e80f AC |
951 | |
952 | lp->next = lwp_list; | |
953 | lwp_list = lp; | |
d6b0e80f | 954 | |
26cb8b7c PA |
955 | return lp; |
956 | } | |
957 | ||
958 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
959 | structure describing the new LWP. The LWP should already be | |
960 | stopped. */ | |
961 | ||
962 | static struct lwp_info * | |
963 | add_lwp (ptid_t ptid) | |
964 | { | |
965 | struct lwp_info *lp; | |
966 | ||
967 | lp = add_initial_lwp (ptid); | |
968 | ||
6e012a6c PA |
969 | /* Let the arch specific bits know about this new thread. Current |
970 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
971 | watchpoints in the new thread. We don't do this for the first |
972 | thread though. See add_initial_lwp. */ | |
973 | if (linux_nat_new_thread != NULL) | |
7b50312a | 974 | linux_nat_new_thread (lp); |
9f0bdab8 | 975 | |
d6b0e80f AC |
976 | return lp; |
977 | } | |
978 | ||
979 | /* Remove the LWP specified by PID from the list. */ | |
980 | ||
981 | static void | |
982 | delete_lwp (ptid_t ptid) | |
983 | { | |
984 | struct lwp_info *lp, *lpprev; | |
985 | ||
986 | lpprev = NULL; | |
987 | ||
988 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
989 | if (ptid_equal (lp->ptid, ptid)) | |
990 | break; | |
991 | ||
992 | if (!lp) | |
993 | return; | |
994 | ||
d6b0e80f AC |
995 | if (lpprev) |
996 | lpprev->next = lp->next; | |
997 | else | |
998 | lwp_list = lp->next; | |
999 | ||
7b50312a | 1000 | lwp_free (lp); |
d6b0e80f AC |
1001 | } |
1002 | ||
1003 | /* Return a pointer to the structure describing the LWP corresponding | |
1004 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1005 | ||
1006 | static struct lwp_info * | |
1007 | find_lwp_pid (ptid_t ptid) | |
1008 | { | |
1009 | struct lwp_info *lp; | |
1010 | int lwp; | |
1011 | ||
dfd4cc63 LM |
1012 | if (ptid_lwp_p (ptid)) |
1013 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 1014 | else |
dfd4cc63 | 1015 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
1016 | |
1017 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 1018 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
1019 | return lp; |
1020 | ||
1021 | return NULL; | |
1022 | } | |
1023 | ||
1024 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1025 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1026 | pointer to the structure describing that LWP immediately. | |
1027 | Otherwise return NULL. */ | |
1028 | ||
1029 | struct lwp_info * | |
d90e17a7 PA |
1030 | iterate_over_lwps (ptid_t filter, |
1031 | int (*callback) (struct lwp_info *, void *), | |
1032 | void *data) | |
d6b0e80f AC |
1033 | { |
1034 | struct lwp_info *lp, *lpnext; | |
1035 | ||
1036 | for (lp = lwp_list; lp; lp = lpnext) | |
1037 | { | |
1038 | lpnext = lp->next; | |
d90e17a7 PA |
1039 | |
1040 | if (ptid_match (lp->ptid, filter)) | |
1041 | { | |
1042 | if ((*callback) (lp, data)) | |
1043 | return lp; | |
1044 | } | |
d6b0e80f AC |
1045 | } |
1046 | ||
1047 | return NULL; | |
1048 | } | |
1049 | ||
2277426b PA |
1050 | /* Update our internal state when changing from one checkpoint to |
1051 | another indicated by NEW_PTID. We can only switch single-threaded | |
1052 | applications, so we only create one new LWP, and the previous list | |
1053 | is discarded. */ | |
f973ed9c DJ |
1054 | |
1055 | void | |
1056 | linux_nat_switch_fork (ptid_t new_ptid) | |
1057 | { | |
1058 | struct lwp_info *lp; | |
1059 | ||
dfd4cc63 | 1060 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 1061 | |
f973ed9c DJ |
1062 | lp = add_lwp (new_ptid); |
1063 | lp->stopped = 1; | |
e26af52f | 1064 | |
2277426b PA |
1065 | /* This changes the thread's ptid while preserving the gdb thread |
1066 | num. Also changes the inferior pid, while preserving the | |
1067 | inferior num. */ | |
1068 | thread_change_ptid (inferior_ptid, new_ptid); | |
1069 | ||
1070 | /* We've just told GDB core that the thread changed target id, but, | |
1071 | in fact, it really is a different thread, with different register | |
1072 | contents. */ | |
1073 | registers_changed (); | |
e26af52f DJ |
1074 | } |
1075 | ||
e26af52f DJ |
1076 | /* Handle the exit of a single thread LP. */ |
1077 | ||
1078 | static void | |
1079 | exit_lwp (struct lwp_info *lp) | |
1080 | { | |
e09875d4 | 1081 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1082 | |
1083 | if (th) | |
e26af52f | 1084 | { |
17faa917 DJ |
1085 | if (print_thread_events) |
1086 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1087 | ||
4f8d22e3 | 1088 | delete_thread (lp->ptid); |
e26af52f DJ |
1089 | } |
1090 | ||
1091 | delete_lwp (lp->ptid); | |
1092 | } | |
1093 | ||
a0ef4274 DJ |
1094 | /* Wait for the LWP specified by LP, which we have just attached to. |
1095 | Returns a wait status for that LWP, to cache. */ | |
1096 | ||
1097 | static int | |
1098 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1099 | int *signalled) | |
1100 | { | |
dfd4cc63 | 1101 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
1102 | int status; |
1103 | ||
644cebc9 | 1104 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1105 | { |
1106 | if (debug_linux_nat) | |
1107 | fprintf_unfiltered (gdb_stdlog, | |
1108 | "LNPAW: Attaching to a stopped process\n"); | |
1109 | ||
1110 | /* The process is definitely stopped. It is in a job control | |
1111 | stop, unless the kernel predates the TASK_STOPPED / | |
1112 | TASK_TRACED distinction, in which case it might be in a | |
1113 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1114 | can kill it, signal it, et cetera. | |
1115 | ||
1116 | First make sure there is a pending SIGSTOP. Since we are | |
1117 | already attached, the process can not transition from stopped | |
1118 | to running without a PTRACE_CONT; so we know this signal will | |
1119 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1120 | probably already in the queue (unless this kernel is old | |
1121 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1122 | is not an RT signal, it can only be queued once. */ | |
1123 | kill_lwp (pid, SIGSTOP); | |
1124 | ||
1125 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1126 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1127 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1128 | } | |
1129 | ||
1130 | /* Make sure the initial process is stopped. The user-level threads | |
1131 | layer might want to poke around in the inferior, and that won't | |
1132 | work if things haven't stabilized yet. */ | |
1133 | new_pid = my_waitpid (pid, &status, 0); | |
1134 | if (new_pid == -1 && errno == ECHILD) | |
1135 | { | |
1136 | if (first) | |
1137 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1138 | ||
1139 | /* Try again with __WCLONE to check cloned processes. */ | |
1140 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1141 | *cloned = 1; | |
1142 | } | |
1143 | ||
dacc9cb2 PP |
1144 | gdb_assert (pid == new_pid); |
1145 | ||
1146 | if (!WIFSTOPPED (status)) | |
1147 | { | |
1148 | /* The pid we tried to attach has apparently just exited. */ | |
1149 | if (debug_linux_nat) | |
1150 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1151 | pid, status_to_str (status)); | |
1152 | return status; | |
1153 | } | |
a0ef4274 DJ |
1154 | |
1155 | if (WSTOPSIG (status) != SIGSTOP) | |
1156 | { | |
1157 | *signalled = 1; | |
1158 | if (debug_linux_nat) | |
1159 | fprintf_unfiltered (gdb_stdlog, | |
1160 | "LNPAW: Received %s after attaching\n", | |
1161 | status_to_str (status)); | |
1162 | } | |
1163 | ||
1164 | return status; | |
1165 | } | |
1166 | ||
84636d28 PA |
1167 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1168 | the new LWP could not be attached, or 1 if we're already auto | |
1169 | attached to this thread, but haven't processed the | |
1170 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1171 | its existance, without considering it an error. */ | |
d6b0e80f | 1172 | |
9ee57c33 | 1173 | int |
93815fbf | 1174 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1175 | { |
9ee57c33 | 1176 | struct lwp_info *lp; |
84636d28 | 1177 | int lwpid; |
d6b0e80f | 1178 | |
dfd4cc63 | 1179 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1180 | |
9ee57c33 | 1181 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1182 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f AC |
1183 | |
1184 | /* We assume that we're already attached to any LWP that has an id | |
1185 | equal to the overall process id, and to any LWP that is already | |
1186 | in our list of LWPs. If we're not seeing exit events from threads | |
1187 | and we've had PID wraparound since we last tried to stop all threads, | |
1188 | this assumption might be wrong; fortunately, this is very unlikely | |
1189 | to happen. */ | |
dfd4cc63 | 1190 | if (lwpid != ptid_get_pid (ptid) && lp == NULL) |
d6b0e80f | 1191 | { |
a0ef4274 | 1192 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1193 | |
84636d28 | 1194 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1195 | { |
96d7229d | 1196 | if (linux_supports_tracefork ()) |
84636d28 PA |
1197 | { |
1198 | /* If we haven't stopped all threads when we get here, | |
1199 | we may have seen a thread listed in thread_db's list, | |
1200 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1201 | that's the case, ignore this new thread, and let | |
1202 | normal event handling discover it later. */ | |
1203 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1204 | { | |
1205 | /* We've already seen this thread stop, but we | |
1206 | haven't seen the PTRACE_EVENT_CLONE extended | |
1207 | event yet. */ | |
84636d28 PA |
1208 | return 0; |
1209 | } | |
1210 | else | |
1211 | { | |
1212 | int new_pid; | |
1213 | int status; | |
1214 | ||
1215 | /* See if we've got a stop for this new child | |
1216 | pending. If so, we're already attached. */ | |
1217 | new_pid = my_waitpid (lwpid, &status, WNOHANG); | |
1218 | if (new_pid == -1 && errno == ECHILD) | |
1219 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1220 | if (new_pid != -1) | |
1221 | { | |
1222 | if (WIFSTOPPED (status)) | |
1223 | add_to_pid_list (&stopped_pids, lwpid, status); | |
84636d28 PA |
1224 | return 1; |
1225 | } | |
1226 | } | |
1227 | } | |
1228 | ||
9ee57c33 DJ |
1229 | /* If we fail to attach to the thread, issue a warning, |
1230 | but continue. One way this can happen is if thread | |
e9efe249 | 1231 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1232 | bug may place threads in the thread list and then fail |
1233 | to create them. */ | |
1234 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1235 | safe_strerror (errno)); | |
1236 | return -1; | |
1237 | } | |
1238 | ||
d6b0e80f AC |
1239 | if (debug_linux_nat) |
1240 | fprintf_unfiltered (gdb_stdlog, | |
1241 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1242 | target_pid_to_str (ptid)); | |
1243 | ||
a0ef4274 | 1244 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1245 | if (!WIFSTOPPED (status)) |
12696c10 | 1246 | return 1; |
dacc9cb2 | 1247 | |
a0ef4274 DJ |
1248 | lp = add_lwp (ptid); |
1249 | lp->stopped = 1; | |
1250 | lp->cloned = cloned; | |
1251 | lp->signalled = signalled; | |
1252 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1253 | { |
a0ef4274 DJ |
1254 | lp->resumed = 1; |
1255 | lp->status = status; | |
d6b0e80f AC |
1256 | } |
1257 | ||
dfd4cc63 | 1258 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1259 | |
1260 | if (debug_linux_nat) | |
1261 | { | |
1262 | fprintf_unfiltered (gdb_stdlog, | |
1263 | "LLAL: waitpid %s received %s\n", | |
1264 | target_pid_to_str (ptid), | |
1265 | status_to_str (status)); | |
1266 | } | |
1267 | } | |
1268 | else | |
1269 | { | |
1270 | /* We assume that the LWP representing the original process is | |
1271 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1272 | that the GNU/linux ptrace layer uses to keep track of |
1273 | threads. Note that this won't have already been done since | |
1274 | the main thread will have, we assume, been stopped by an | |
1275 | attach from a different layer. */ | |
9ee57c33 DJ |
1276 | if (lp == NULL) |
1277 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1278 | lp->stopped = 1; |
1279 | } | |
9ee57c33 | 1280 | |
25289eb2 | 1281 | lp->last_resume_kind = resume_stop; |
9ee57c33 | 1282 | return 0; |
d6b0e80f AC |
1283 | } |
1284 | ||
b84876c2 | 1285 | static void |
136d6dae VP |
1286 | linux_nat_create_inferior (struct target_ops *ops, |
1287 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1288 | int from_tty) |
1289 | { | |
10568435 JK |
1290 | #ifdef HAVE_PERSONALITY |
1291 | int personality_orig = 0, personality_set = 0; | |
1292 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1293 | |
1294 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1295 | we have to mask the async mode. */ | |
1296 | ||
10568435 JK |
1297 | #ifdef HAVE_PERSONALITY |
1298 | if (disable_randomization) | |
1299 | { | |
1300 | errno = 0; | |
1301 | personality_orig = personality (0xffffffff); | |
1302 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1303 | { | |
1304 | personality_set = 1; | |
1305 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1306 | } | |
1307 | if (errno != 0 || (personality_set | |
1308 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1309 | warning (_("Error disabling address space randomization: %s"), | |
1310 | safe_strerror (errno)); | |
1311 | } | |
1312 | #endif /* HAVE_PERSONALITY */ | |
1313 | ||
2455069d | 1314 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1315 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1316 | |
136d6dae | 1317 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1318 | |
10568435 JK |
1319 | #ifdef HAVE_PERSONALITY |
1320 | if (personality_set) | |
1321 | { | |
1322 | errno = 0; | |
1323 | personality (personality_orig); | |
1324 | if (errno != 0) | |
1325 | warning (_("Error restoring address space randomization: %s"), | |
1326 | safe_strerror (errno)); | |
1327 | } | |
1328 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1329 | } |
1330 | ||
d6b0e80f | 1331 | static void |
c0939df1 | 1332 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1333 | { |
1334 | struct lwp_info *lp; | |
d6b0e80f | 1335 | int status; |
af990527 | 1336 | ptid_t ptid; |
87b0bb13 | 1337 | volatile struct gdb_exception ex; |
d6b0e80f | 1338 | |
2455069d | 1339 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1340 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1341 | |
87b0bb13 JK |
1342 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
1343 | { | |
1344 | linux_ops->to_attach (ops, args, from_tty); | |
1345 | } | |
1346 | if (ex.reason < 0) | |
1347 | { | |
1348 | pid_t pid = parse_pid_to_attach (args); | |
1349 | struct buffer buffer; | |
1350 | char *message, *buffer_s; | |
1351 | ||
1352 | message = xstrdup (ex.message); | |
1353 | make_cleanup (xfree, message); | |
1354 | ||
1355 | buffer_init (&buffer); | |
7ae1a6a6 | 1356 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1357 | |
1358 | buffer_grow_str0 (&buffer, ""); | |
1359 | buffer_s = buffer_finish (&buffer); | |
1360 | make_cleanup (xfree, buffer_s); | |
1361 | ||
7ae1a6a6 PA |
1362 | if (*buffer_s != '\0') |
1363 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1364 | else | |
1365 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1366 | } |
d6b0e80f | 1367 | |
af990527 PA |
1368 | /* The ptrace base target adds the main thread with (pid,0,0) |
1369 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1370 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1371 | ptid_get_pid (inferior_ptid), | |
1372 | 0); | |
af990527 PA |
1373 | thread_change_ptid (inferior_ptid, ptid); |
1374 | ||
9f0bdab8 | 1375 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1376 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1377 | |
1378 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1379 | &lp->signalled); | |
dacc9cb2 PP |
1380 | if (!WIFSTOPPED (status)) |
1381 | { | |
1382 | if (WIFEXITED (status)) | |
1383 | { | |
1384 | int exit_code = WEXITSTATUS (status); | |
1385 | ||
1386 | target_terminal_ours (); | |
1387 | target_mourn_inferior (); | |
1388 | if (exit_code == 0) | |
1389 | error (_("Unable to attach: program exited normally.")); | |
1390 | else | |
1391 | error (_("Unable to attach: program exited with code %d."), | |
1392 | exit_code); | |
1393 | } | |
1394 | else if (WIFSIGNALED (status)) | |
1395 | { | |
2ea28649 | 1396 | enum gdb_signal signo; |
dacc9cb2 PP |
1397 | |
1398 | target_terminal_ours (); | |
1399 | target_mourn_inferior (); | |
1400 | ||
2ea28649 | 1401 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1402 | error (_("Unable to attach: program terminated with signal " |
1403 | "%s, %s."), | |
2ea28649 PA |
1404 | gdb_signal_to_name (signo), |
1405 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1406 | } |
1407 | ||
1408 | internal_error (__FILE__, __LINE__, | |
1409 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1410 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1411 | } |
1412 | ||
a0ef4274 | 1413 | lp->stopped = 1; |
9f0bdab8 | 1414 | |
a0ef4274 | 1415 | /* Save the wait status to report later. */ |
d6b0e80f | 1416 | lp->resumed = 1; |
a0ef4274 DJ |
1417 | if (debug_linux_nat) |
1418 | fprintf_unfiltered (gdb_stdlog, | |
1419 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1420 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1421 | |
7feb7d06 PA |
1422 | lp->status = status; |
1423 | ||
1424 | if (target_can_async_p ()) | |
1425 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1426 | } |
1427 | ||
a0ef4274 DJ |
1428 | /* Get pending status of LP. */ |
1429 | static int | |
1430 | get_pending_status (struct lwp_info *lp, int *status) | |
1431 | { | |
a493e3e2 | 1432 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1433 | |
1434 | /* If we paused threads momentarily, we may have stored pending | |
1435 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1436 | and GDB core hasn't seen any signal for those threads. | |
1437 | Otherwise, the last signal reported to the core is found in the | |
1438 | thread object's stop_signal. | |
1439 | ||
1440 | There's a corner case that isn't handled here at present. Only | |
1441 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1442 | stop_signal make sense as a real signal to pass to the inferior. | |
1443 | Some catchpoint related events, like | |
1444 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1445 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1446 | those traps are debug API (ptrace in our case) related and |
1447 | induced; the inferior wouldn't see them if it wasn't being | |
1448 | traced. Hence, we should never pass them to the inferior, even | |
1449 | when set to pass state. Since this corner case isn't handled by | |
1450 | infrun.c when proceeding with a signal, for consistency, neither | |
1451 | do we handle it here (or elsewhere in the file we check for | |
1452 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1453 | this is really a corner case. */ | |
1454 | ||
1455 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1456 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1457 | else if (lp->status) |
2ea28649 | 1458 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1459 | else if (non_stop && !is_executing (lp->ptid)) |
1460 | { | |
1461 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1462 | |
16c381f0 | 1463 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1464 | } |
1465 | else if (!non_stop) | |
a0ef4274 | 1466 | { |
ca2163eb PA |
1467 | struct target_waitstatus last; |
1468 | ptid_t last_ptid; | |
4c28f408 | 1469 | |
ca2163eb | 1470 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1471 | |
dfd4cc63 | 1472 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1473 | { |
e09875d4 | 1474 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1475 | |
16c381f0 | 1476 | signo = tp->suspend.stop_signal; |
4c28f408 | 1477 | } |
ca2163eb | 1478 | } |
4c28f408 | 1479 | |
ca2163eb | 1480 | *status = 0; |
4c28f408 | 1481 | |
a493e3e2 | 1482 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1483 | { |
1484 | if (debug_linux_nat) | |
1485 | fprintf_unfiltered (gdb_stdlog, | |
1486 | "GPT: lwp %s has no pending signal\n", | |
1487 | target_pid_to_str (lp->ptid)); | |
1488 | } | |
1489 | else if (!signal_pass_state (signo)) | |
1490 | { | |
1491 | if (debug_linux_nat) | |
3e43a32a MS |
1492 | fprintf_unfiltered (gdb_stdlog, |
1493 | "GPT: lwp %s had signal %s, " | |
1494 | "but it is in no pass state\n", | |
ca2163eb | 1495 | target_pid_to_str (lp->ptid), |
2ea28649 | 1496 | gdb_signal_to_string (signo)); |
a0ef4274 | 1497 | } |
a0ef4274 | 1498 | else |
4c28f408 | 1499 | { |
2ea28649 | 1500 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1501 | |
1502 | if (debug_linux_nat) | |
1503 | fprintf_unfiltered (gdb_stdlog, | |
1504 | "GPT: lwp %s has pending signal %s\n", | |
1505 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1506 | gdb_signal_to_string (signo)); |
4c28f408 | 1507 | } |
a0ef4274 DJ |
1508 | |
1509 | return 0; | |
1510 | } | |
1511 | ||
d6b0e80f AC |
1512 | static int |
1513 | detach_callback (struct lwp_info *lp, void *data) | |
1514 | { | |
1515 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1516 | ||
1517 | if (debug_linux_nat && lp->status) | |
1518 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1519 | strsignal (WSTOPSIG (lp->status)), | |
1520 | target_pid_to_str (lp->ptid)); | |
1521 | ||
a0ef4274 DJ |
1522 | /* If there is a pending SIGSTOP, get rid of it. */ |
1523 | if (lp->signalled) | |
d6b0e80f | 1524 | { |
d6b0e80f AC |
1525 | if (debug_linux_nat) |
1526 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1527 | "DC: Sending SIGCONT to %s\n", |
1528 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1529 | |
dfd4cc63 | 1530 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1531 | lp->signalled = 0; |
d6b0e80f AC |
1532 | } |
1533 | ||
1534 | /* We don't actually detach from the LWP that has an id equal to the | |
1535 | overall process id just yet. */ | |
dfd4cc63 | 1536 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1537 | { |
a0ef4274 DJ |
1538 | int status = 0; |
1539 | ||
1540 | /* Pass on any pending signal for this LWP. */ | |
1541 | get_pending_status (lp, &status); | |
1542 | ||
7b50312a PA |
1543 | if (linux_nat_prepare_to_resume != NULL) |
1544 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1545 | errno = 0; |
dfd4cc63 | 1546 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1547 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1548 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1549 | safe_strerror (errno)); |
1550 | ||
1551 | if (debug_linux_nat) | |
1552 | fprintf_unfiltered (gdb_stdlog, | |
1553 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1554 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1555 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1556 | |
1557 | delete_lwp (lp->ptid); | |
1558 | } | |
1559 | ||
1560 | return 0; | |
1561 | } | |
1562 | ||
1563 | static void | |
52554a0e | 1564 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1565 | { |
b84876c2 | 1566 | int pid; |
a0ef4274 | 1567 | int status; |
d90e17a7 PA |
1568 | struct lwp_info *main_lwp; |
1569 | ||
dfd4cc63 | 1570 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1571 | |
ae5e0686 MK |
1572 | /* Don't unregister from the event loop, as there may be other |
1573 | inferiors running. */ | |
b84876c2 | 1574 | |
4c28f408 PA |
1575 | /* Stop all threads before detaching. ptrace requires that the |
1576 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1577 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1578 | /* ... and wait until all of them have reported back that |
1579 | they're no longer running. */ | |
d90e17a7 | 1580 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1581 | |
d90e17a7 | 1582 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1583 | |
1584 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1585 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1586 | |
1587 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1588 | |
a0ef4274 DJ |
1589 | /* Pass on any pending signal for the last LWP. */ |
1590 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1591 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1592 | && WIFSTOPPED (status)) |
1593 | { | |
52554a0e TT |
1594 | char *tem; |
1595 | ||
a0ef4274 DJ |
1596 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1597 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1598 | tem = alloca (8); |
cde33bf1 | 1599 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1600 | args = tem; |
ddabfc73 TT |
1601 | if (debug_linux_nat) |
1602 | fprintf_unfiltered (gdb_stdlog, | |
1603 | "LND: Sending signal %s to %s\n", | |
1604 | args, | |
1605 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1606 | } |
1607 | ||
7b50312a PA |
1608 | if (linux_nat_prepare_to_resume != NULL) |
1609 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1610 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1611 | |
7a7d3353 PA |
1612 | if (forks_exist_p ()) |
1613 | { | |
1614 | /* Multi-fork case. The current inferior_ptid is being detached | |
1615 | from, but there are other viable forks to debug. Detach from | |
1616 | the current fork, and context-switch to the first | |
1617 | available. */ | |
1618 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1619 | } |
1620 | else | |
1621 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1622 | } |
1623 | ||
1624 | /* Resume LP. */ | |
1625 | ||
25289eb2 | 1626 | static void |
e5ef252a | 1627 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1628 | { |
25289eb2 | 1629 | if (lp->stopped) |
6c95b8df | 1630 | { |
dfd4cc63 | 1631 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
25289eb2 PA |
1632 | |
1633 | if (inf->vfork_child != NULL) | |
1634 | { | |
1635 | if (debug_linux_nat) | |
1636 | fprintf_unfiltered (gdb_stdlog, | |
1637 | "RC: Not resuming %s (vfork parent)\n", | |
1638 | target_pid_to_str (lp->ptid)); | |
1639 | } | |
1640 | else if (lp->status == 0 | |
1641 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
1642 | { | |
1643 | if (debug_linux_nat) | |
1644 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1645 | "RC: Resuming sibling %s, %s, %s\n", |
1646 | target_pid_to_str (lp->ptid), | |
1647 | (signo != GDB_SIGNAL_0 | |
1648 | ? strsignal (gdb_signal_to_host (signo)) | |
1649 | : "0"), | |
1650 | step ? "step" : "resume"); | |
25289eb2 | 1651 | |
7b50312a PA |
1652 | if (linux_nat_prepare_to_resume != NULL) |
1653 | linux_nat_prepare_to_resume (lp); | |
25289eb2 | 1654 | linux_ops->to_resume (linux_ops, |
dfd4cc63 | 1655 | pid_to_ptid (ptid_get_lwp (lp->ptid)), |
e5ef252a | 1656 | step, signo); |
25289eb2 PA |
1657 | lp->stopped = 0; |
1658 | lp->step = step; | |
25289eb2 PA |
1659 | lp->stopped_by_watchpoint = 0; |
1660 | } | |
1661 | else | |
1662 | { | |
1663 | if (debug_linux_nat) | |
1664 | fprintf_unfiltered (gdb_stdlog, | |
1665 | "RC: Not resuming sibling %s (has pending)\n", | |
1666 | target_pid_to_str (lp->ptid)); | |
1667 | } | |
6c95b8df | 1668 | } |
25289eb2 | 1669 | else |
d6b0e80f | 1670 | { |
d90e17a7 PA |
1671 | if (debug_linux_nat) |
1672 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1673 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1674 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1675 | } |
25289eb2 | 1676 | } |
d6b0e80f | 1677 | |
8817a6f2 PA |
1678 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1679 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1680 | |
25289eb2 | 1681 | static int |
8817a6f2 | 1682 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1683 | { |
e5ef252a PA |
1684 | enum gdb_signal signo = GDB_SIGNAL_0; |
1685 | ||
8817a6f2 PA |
1686 | if (lp == except) |
1687 | return 0; | |
1688 | ||
e5ef252a PA |
1689 | if (lp->stopped) |
1690 | { | |
1691 | struct thread_info *thread; | |
1692 | ||
1693 | thread = find_thread_ptid (lp->ptid); | |
1694 | if (thread != NULL) | |
1695 | { | |
70509625 | 1696 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1697 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1698 | } | |
1699 | } | |
1700 | ||
1701 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1702 | return 0; |
1703 | } | |
1704 | ||
1705 | static int | |
1706 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1707 | { | |
1708 | lp->resumed = 0; | |
25289eb2 | 1709 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1710 | return 0; |
1711 | } | |
1712 | ||
1713 | static int | |
1714 | resume_set_callback (struct lwp_info *lp, void *data) | |
1715 | { | |
1716 | lp->resumed = 1; | |
25289eb2 | 1717 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1718 | return 0; |
1719 | } | |
1720 | ||
1721 | static void | |
28439f5e | 1722 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1723 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1724 | { |
1725 | struct lwp_info *lp; | |
d90e17a7 | 1726 | int resume_many; |
d6b0e80f | 1727 | |
76f50ad1 DJ |
1728 | if (debug_linux_nat) |
1729 | fprintf_unfiltered (gdb_stdlog, | |
1730 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1731 | step ? "step" : "resume", | |
1732 | target_pid_to_str (ptid), | |
a493e3e2 | 1733 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1734 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1735 | target_pid_to_str (inferior_ptid)); |
1736 | ||
d6b0e80f | 1737 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1738 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1739 | || ptid_is_pid (ptid)); | |
4c28f408 | 1740 | |
e3e9f5a2 PA |
1741 | /* Mark the lwps we're resuming as resumed. */ |
1742 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1743 | |
d90e17a7 PA |
1744 | /* See if it's the current inferior that should be handled |
1745 | specially. */ | |
1746 | if (resume_many) | |
1747 | lp = find_lwp_pid (inferior_ptid); | |
1748 | else | |
1749 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1750 | gdb_assert (lp != NULL); |
d6b0e80f | 1751 | |
9f0bdab8 DJ |
1752 | /* Remember if we're stepping. */ |
1753 | lp->step = step; | |
25289eb2 | 1754 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1755 | |
9f0bdab8 DJ |
1756 | /* If we have a pending wait status for this thread, there is no |
1757 | point in resuming the process. But first make sure that | |
1758 | linux_nat_wait won't preemptively handle the event - we | |
1759 | should never take this short-circuit if we are going to | |
1760 | leave LP running, since we have skipped resuming all the | |
1761 | other threads. This bit of code needs to be synchronized | |
1762 | with linux_nat_wait. */ | |
76f50ad1 | 1763 | |
9f0bdab8 DJ |
1764 | if (lp->status && WIFSTOPPED (lp->status)) |
1765 | { | |
2455069d UW |
1766 | if (!lp->step |
1767 | && WSTOPSIG (lp->status) | |
1768 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1769 | { |
9f0bdab8 DJ |
1770 | if (debug_linux_nat) |
1771 | fprintf_unfiltered (gdb_stdlog, | |
1772 | "LLR: Not short circuiting for ignored " | |
1773 | "status 0x%x\n", lp->status); | |
1774 | ||
d6b0e80f AC |
1775 | /* FIXME: What should we do if we are supposed to continue |
1776 | this thread with a signal? */ | |
a493e3e2 | 1777 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1778 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1779 | lp->status = 0; |
1780 | } | |
1781 | } | |
76f50ad1 | 1782 | |
6c95b8df | 1783 | if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) |
9f0bdab8 DJ |
1784 | { |
1785 | /* FIXME: What should we do if we are supposed to continue | |
1786 | this thread with a signal? */ | |
a493e3e2 | 1787 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1788 | |
9f0bdab8 DJ |
1789 | if (debug_linux_nat) |
1790 | fprintf_unfiltered (gdb_stdlog, | |
1791 | "LLR: Short circuiting for status 0x%x\n", | |
1792 | lp->status); | |
d6b0e80f | 1793 | |
7feb7d06 PA |
1794 | if (target_can_async_p ()) |
1795 | { | |
1796 | target_async (inferior_event_handler, 0); | |
1797 | /* Tell the event loop we have something to process. */ | |
1798 | async_file_mark (); | |
1799 | } | |
9f0bdab8 | 1800 | return; |
d6b0e80f AC |
1801 | } |
1802 | ||
d90e17a7 | 1803 | if (resume_many) |
8817a6f2 | 1804 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 PA |
1805 | |
1806 | /* Convert to something the lower layer understands. */ | |
dfd4cc63 | 1807 | ptid = pid_to_ptid (ptid_get_lwp (lp->ptid)); |
d6b0e80f | 1808 | |
7b50312a PA |
1809 | if (linux_nat_prepare_to_resume != NULL) |
1810 | linux_nat_prepare_to_resume (lp); | |
28439f5e | 1811 | linux_ops->to_resume (linux_ops, ptid, step, signo); |
ebec9a0f | 1812 | lp->stopped_by_watchpoint = 0; |
8817a6f2 | 1813 | lp->stopped = 0; |
9f0bdab8 | 1814 | |
d6b0e80f AC |
1815 | if (debug_linux_nat) |
1816 | fprintf_unfiltered (gdb_stdlog, | |
1817 | "LLR: %s %s, %s (resume event thread)\n", | |
1818 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1819 | target_pid_to_str (ptid), | |
a493e3e2 | 1820 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1821 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1822 | |
1823 | if (target_can_async_p ()) | |
8ea051c5 | 1824 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1825 | } |
1826 | ||
c5f62d5f | 1827 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1828 | |
1829 | static int | |
1830 | kill_lwp (int lwpid, int signo) | |
1831 | { | |
c5f62d5f DE |
1832 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1833 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1834 | |
1835 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1836 | { |
1837 | static int tkill_failed; | |
1838 | ||
1839 | if (!tkill_failed) | |
1840 | { | |
1841 | int ret; | |
1842 | ||
1843 | errno = 0; | |
1844 | ret = syscall (__NR_tkill, lwpid, signo); | |
1845 | if (errno != ENOSYS) | |
1846 | return ret; | |
1847 | tkill_failed = 1; | |
1848 | } | |
1849 | } | |
d6b0e80f AC |
1850 | #endif |
1851 | ||
1852 | return kill (lwpid, signo); | |
1853 | } | |
1854 | ||
ca2163eb PA |
1855 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1856 | event, check if the core is interested in it: if not, ignore the | |
1857 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1858 | syscall entry/exit status, since the ptrace event itself doesn't | |
1859 | indicate it, and report the trap to higher layers. */ | |
1860 | ||
1861 | static int | |
1862 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1863 | { | |
1864 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1865 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1866 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1867 | ||
1868 | if (stopping) | |
1869 | { | |
1870 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1871 | makes it so that the LWP reports an immediate syscall return, | |
1872 | followed by the SIGSTOP. Skip seeing that "return" using | |
1873 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1874 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1875 | entry event. If we didn't do this (and returned 0), we'd | |
1876 | leave a syscall entry pending, and our caller, by using | |
1877 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1878 | itself. Later, when the user re-resumes this LWP, we'd see | |
1879 | another syscall entry event and we'd mistake it for a return. | |
1880 | ||
1881 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1882 | (leaving immediately with LWP->signalled set, without issuing | |
1883 | a PTRACE_CONT), it would still be problematic to leave this | |
1884 | syscall enter pending, as later when the thread is resumed, | |
1885 | it would then see the same syscall exit mentioned above, | |
1886 | followed by the delayed SIGSTOP, while the syscall didn't | |
1887 | actually get to execute. It seems it would be even more | |
1888 | confusing to the user. */ | |
1889 | ||
1890 | if (debug_linux_nat) | |
1891 | fprintf_unfiltered (gdb_stdlog, | |
1892 | "LHST: ignoring syscall %d " | |
1893 | "for LWP %ld (stopping threads), " | |
1894 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1895 | syscall_number, | |
dfd4cc63 | 1896 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1897 | |
1898 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1899 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1900 | lp->stopped = 0; |
ca2163eb PA |
1901 | return 1; |
1902 | } | |
1903 | ||
1904 | if (catch_syscall_enabled ()) | |
1905 | { | |
1906 | /* Always update the entry/return state, even if this particular | |
1907 | syscall isn't interesting to the core now. In async mode, | |
1908 | the user could install a new catchpoint for this syscall | |
1909 | between syscall enter/return, and we'll need to know to | |
1910 | report a syscall return if that happens. */ | |
1911 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1912 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1913 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1914 | ||
1915 | if (catching_syscall_number (syscall_number)) | |
1916 | { | |
1917 | /* Alright, an event to report. */ | |
1918 | ourstatus->kind = lp->syscall_state; | |
1919 | ourstatus->value.syscall_number = syscall_number; | |
1920 | ||
1921 | if (debug_linux_nat) | |
1922 | fprintf_unfiltered (gdb_stdlog, | |
1923 | "LHST: stopping for %s of syscall %d" | |
1924 | " for LWP %ld\n", | |
3e43a32a MS |
1925 | lp->syscall_state |
1926 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1927 | ? "entry" : "return", |
1928 | syscall_number, | |
dfd4cc63 | 1929 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1930 | return 0; |
1931 | } | |
1932 | ||
1933 | if (debug_linux_nat) | |
1934 | fprintf_unfiltered (gdb_stdlog, | |
1935 | "LHST: ignoring %s of syscall %d " | |
1936 | "for LWP %ld\n", | |
1937 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1938 | ? "entry" : "return", | |
1939 | syscall_number, | |
dfd4cc63 | 1940 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1941 | } |
1942 | else | |
1943 | { | |
1944 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1945 | before on this LWP, it could happen that the user removes all | |
1946 | syscall catchpoints before we get to process this event. | |
1947 | There are two noteworthy issues here: | |
1948 | ||
1949 | - When stopped at a syscall entry event, resuming with | |
1950 | PT_STEP still resumes executing the syscall and reports a | |
1951 | syscall return. | |
1952 | ||
1953 | - Only PT_SYSCALL catches syscall enters. If we last | |
1954 | single-stepped this thread, then this event can't be a | |
1955 | syscall enter. If we last single-stepped this thread, this | |
1956 | has to be a syscall exit. | |
1957 | ||
1958 | The points above mean that the next resume, be it PT_STEP or | |
1959 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1960 | if (debug_linux_nat) | |
1961 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1962 | "LHST: caught syscall event " |
1963 | "with no syscall catchpoints." | |
ca2163eb PA |
1964 | " %d for LWP %ld, ignoring\n", |
1965 | syscall_number, | |
dfd4cc63 | 1966 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1967 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1968 | } | |
1969 | ||
1970 | /* The core isn't interested in this event. For efficiency, avoid | |
1971 | stopping all threads only to have the core resume them all again. | |
1972 | Since we're not stopping threads, if we're still syscall tracing | |
1973 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1974 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1975 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1976 | ||
1977 | /* Note that gdbarch_get_syscall_number may access registers, hence | |
1978 | fill a regcache. */ | |
1979 | registers_changed (); | |
7b50312a PA |
1980 | if (linux_nat_prepare_to_resume != NULL) |
1981 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 1982 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 1983 | lp->step, GDB_SIGNAL_0); |
8817a6f2 | 1984 | lp->stopped = 0; |
ca2163eb PA |
1985 | return 1; |
1986 | } | |
1987 | ||
3d799a95 DJ |
1988 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1989 | event, we need to add the new LWP to our list (and not report the | |
1990 | trap to higher layers). This function returns non-zero if the | |
1991 | event should be ignored and we should wait again. If STOPPING is | |
1992 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1993 | |
1994 | static int | |
3d799a95 DJ |
1995 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1996 | int stopping) | |
d6b0e80f | 1997 | { |
dfd4cc63 | 1998 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1999 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
3d799a95 | 2000 | int event = status >> 16; |
d6b0e80f | 2001 | |
3d799a95 DJ |
2002 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
2003 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 2004 | { |
3d799a95 DJ |
2005 | unsigned long new_pid; |
2006 | int ret; | |
2007 | ||
2008 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 2009 | |
3d799a95 DJ |
2010 | /* If we haven't already seen the new PID stop, wait for it now. */ |
2011 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2012 | { | |
2013 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2014 | hits the SIGSTOP, but we're already attached. */ | |
2015 | ret = my_waitpid (new_pid, &status, | |
2016 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2017 | if (ret == -1) | |
2018 | perror_with_name (_("waiting for new child")); | |
2019 | else if (ret != new_pid) | |
2020 | internal_error (__FILE__, __LINE__, | |
2021 | _("wait returned unexpected PID %d"), ret); | |
2022 | else if (!WIFSTOPPED (status)) | |
2023 | internal_error (__FILE__, __LINE__, | |
2024 | _("wait returned unexpected status 0x%x"), status); | |
2025 | } | |
2026 | ||
3a3e9ee3 | 2027 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2028 | |
26cb8b7c PA |
2029 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2030 | { | |
2031 | /* The arch-specific native code may need to know about new | |
2032 | forks even if those end up never mapped to an | |
2033 | inferior. */ | |
2034 | if (linux_nat_new_fork != NULL) | |
2035 | linux_nat_new_fork (lp, new_pid); | |
2036 | } | |
2037 | ||
2277426b | 2038 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2039 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2040 | { |
2277426b PA |
2041 | /* Handle checkpointing by linux-fork.c here as a special |
2042 | case. We don't want the follow-fork-mode or 'catch fork' | |
2043 | to interfere with this. */ | |
2044 | ||
2045 | /* This won't actually modify the breakpoint list, but will | |
2046 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2047 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2048 | |
2049 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2050 | if (!find_fork_pid (new_pid)) |
2051 | add_fork (new_pid); | |
2277426b PA |
2052 | |
2053 | /* Report as spurious, so that infrun doesn't want to follow | |
2054 | this fork. We're actually doing an infcall in | |
2055 | linux-fork.c. */ | |
2056 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2057 | |
2058 | /* Report the stop to the core. */ | |
2059 | return 0; | |
2060 | } | |
2061 | ||
3d799a95 DJ |
2062 | if (event == PTRACE_EVENT_FORK) |
2063 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2064 | else if (event == PTRACE_EVENT_VFORK) | |
2065 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2066 | else |
3d799a95 | 2067 | { |
78768c4a JK |
2068 | struct lwp_info *new_lp; |
2069 | ||
3d799a95 | 2070 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2071 | |
3c4d7e12 PA |
2072 | if (debug_linux_nat) |
2073 | fprintf_unfiltered (gdb_stdlog, | |
2074 | "LHEW: Got clone event " | |
2075 | "from LWP %d, new child is LWP %ld\n", | |
2076 | pid, new_pid); | |
2077 | ||
dfd4cc63 | 2078 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2079 | new_lp->cloned = 1; |
4c28f408 | 2080 | new_lp->stopped = 1; |
d6b0e80f | 2081 | |
3d799a95 DJ |
2082 | if (WSTOPSIG (status) != SIGSTOP) |
2083 | { | |
2084 | /* This can happen if someone starts sending signals to | |
2085 | the new thread before it gets a chance to run, which | |
2086 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2087 | This is an unlikely case, and harder to handle for | |
2088 | fork / vfork than for clone, so we do not try - but | |
2089 | we handle it for clone events here. We'll send | |
2090 | the other signal on to the thread below. */ | |
2091 | ||
2092 | new_lp->signalled = 1; | |
2093 | } | |
2094 | else | |
79395f92 PA |
2095 | { |
2096 | struct thread_info *tp; | |
2097 | ||
2098 | /* When we stop for an event in some other thread, and | |
2099 | pull the thread list just as this thread has cloned, | |
2100 | we'll have seen the new thread in the thread_db list | |
2101 | before handling the CLONE event (glibc's | |
2102 | pthread_create adds the new thread to the thread list | |
2103 | before clone'ing, and has the kernel fill in the | |
2104 | thread's tid on the clone call with | |
2105 | CLONE_PARENT_SETTID). If that happened, and the core | |
2106 | had requested the new thread to stop, we'll have | |
2107 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2108 | RT signal, it can only be queued once. We need to be | |
2109 | careful to not resume the LWP if we wanted it to | |
2110 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2111 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2112 | tp = find_thread_ptid (new_lp->ptid); |
2113 | if (tp != NULL && tp->stop_requested) | |
2114 | new_lp->last_resume_kind = resume_stop; | |
2115 | else | |
2116 | status = 0; | |
2117 | } | |
d6b0e80f | 2118 | |
4c28f408 | 2119 | if (non_stop) |
3d799a95 | 2120 | { |
4c28f408 PA |
2121 | /* Add the new thread to GDB's lists as soon as possible |
2122 | so that: | |
2123 | ||
2124 | 1) the frontend doesn't have to wait for a stop to | |
2125 | display them, and, | |
2126 | ||
2127 | 2) we tag it with the correct running state. */ | |
2128 | ||
2129 | /* If the thread_db layer is active, let it know about | |
2130 | this new thread, and add it to GDB's list. */ | |
2131 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
2132 | { | |
2133 | /* We're not using thread_db. Add it to GDB's | |
2134 | list. */ | |
dfd4cc63 | 2135 | target_post_attach (ptid_get_lwp (new_lp->ptid)); |
4c28f408 PA |
2136 | add_thread (new_lp->ptid); |
2137 | } | |
2138 | ||
2139 | if (!stopping) | |
2140 | { | |
2141 | set_running (new_lp->ptid, 1); | |
2142 | set_executing (new_lp->ptid, 1); | |
e21ffe51 PA |
2143 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced |
2144 | resume_stop. */ | |
2145 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2146 | } |
2147 | } | |
2148 | ||
79395f92 PA |
2149 | if (status != 0) |
2150 | { | |
2151 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2152 | gdb_assert (new_lp->status == 0); | |
2153 | ||
2154 | /* Save the wait status to report later. */ | |
2155 | if (debug_linux_nat) | |
2156 | fprintf_unfiltered (gdb_stdlog, | |
2157 | "LHEW: waitpid of new LWP %ld, " | |
2158 | "saving status %s\n", | |
dfd4cc63 | 2159 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2160 | status_to_str (status)); |
2161 | new_lp->status = status; | |
2162 | } | |
2163 | ||
ca2163eb PA |
2164 | /* Note the need to use the low target ops to resume, to |
2165 | handle resuming with PT_SYSCALL if we have syscall | |
2166 | catchpoints. */ | |
4c28f408 PA |
2167 | if (!stopping) |
2168 | { | |
3d799a95 | 2169 | new_lp->resumed = 1; |
ca2163eb | 2170 | |
79395f92 | 2171 | if (status == 0) |
ad34eb2f | 2172 | { |
e21ffe51 | 2173 | gdb_assert (new_lp->last_resume_kind == resume_continue); |
ad34eb2f JK |
2174 | if (debug_linux_nat) |
2175 | fprintf_unfiltered (gdb_stdlog, | |
79395f92 | 2176 | "LHEW: resuming new LWP %ld\n", |
dfd4cc63 | 2177 | ptid_get_lwp (new_lp->ptid)); |
7b50312a PA |
2178 | if (linux_nat_prepare_to_resume != NULL) |
2179 | linux_nat_prepare_to_resume (new_lp); | |
79395f92 | 2180 | linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid), |
a493e3e2 | 2181 | 0, GDB_SIGNAL_0); |
79395f92 | 2182 | new_lp->stopped = 0; |
ad34eb2f JK |
2183 | } |
2184 | } | |
d6b0e80f | 2185 | |
3d799a95 DJ |
2186 | if (debug_linux_nat) |
2187 | fprintf_unfiltered (gdb_stdlog, | |
3c4d7e12 | 2188 | "LHEW: resuming parent LWP %d\n", pid); |
7b50312a PA |
2189 | if (linux_nat_prepare_to_resume != NULL) |
2190 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
2191 | linux_ops->to_resume (linux_ops, |
2192 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
a493e3e2 | 2193 | 0, GDB_SIGNAL_0); |
8817a6f2 | 2194 | lp->stopped = 0; |
3d799a95 DJ |
2195 | return 1; |
2196 | } | |
2197 | ||
2198 | return 0; | |
d6b0e80f AC |
2199 | } |
2200 | ||
3d799a95 DJ |
2201 | if (event == PTRACE_EVENT_EXEC) |
2202 | { | |
a75724bc PA |
2203 | if (debug_linux_nat) |
2204 | fprintf_unfiltered (gdb_stdlog, | |
2205 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2206 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2207 | |
3d799a95 DJ |
2208 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2209 | ourstatus->value.execd_pathname | |
8dd27370 | 2210 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2211 | |
6c95b8df PA |
2212 | return 0; |
2213 | } | |
2214 | ||
2215 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2216 | { | |
2217 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2218 | { |
6c95b8df | 2219 | if (debug_linux_nat) |
3e43a32a MS |
2220 | fprintf_unfiltered (gdb_stdlog, |
2221 | "LHEW: Got expected PTRACE_EVENT_" | |
2222 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2223 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2224 | |
6c95b8df PA |
2225 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2226 | return 0; | |
3d799a95 DJ |
2227 | } |
2228 | ||
6c95b8df | 2229 | if (debug_linux_nat) |
3e43a32a MS |
2230 | fprintf_unfiltered (gdb_stdlog, |
2231 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
2232 | "from LWP %ld: resuming\n", | |
dfd4cc63 LM |
2233 | ptid_get_lwp (lp->ptid)); |
2234 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); | |
6c95b8df | 2235 | return 1; |
3d799a95 DJ |
2236 | } |
2237 | ||
2238 | internal_error (__FILE__, __LINE__, | |
2239 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2240 | } |
2241 | ||
2242 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2243 | exited. */ | |
2244 | ||
2245 | static int | |
2246 | wait_lwp (struct lwp_info *lp) | |
2247 | { | |
2248 | pid_t pid; | |
432b4d03 | 2249 | int status = 0; |
d6b0e80f | 2250 | int thread_dead = 0; |
432b4d03 | 2251 | sigset_t prev_mask; |
d6b0e80f AC |
2252 | |
2253 | gdb_assert (!lp->stopped); | |
2254 | gdb_assert (lp->status == 0); | |
2255 | ||
432b4d03 JK |
2256 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2257 | block_child_signals (&prev_mask); | |
2258 | ||
2259 | for (;;) | |
d6b0e80f | 2260 | { |
432b4d03 JK |
2261 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2262 | was right and we should just call sigsuspend. */ | |
2263 | ||
dfd4cc63 | 2264 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2265 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2266 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2267 | if (pid == -1 && errno == ECHILD) |
2268 | { | |
2269 | /* The thread has previously exited. We need to delete it | |
2270 | now because, for some vendor 2.4 kernels with NPTL | |
2271 | support backported, there won't be an exit event unless | |
2272 | it is the main thread. 2.6 kernels will report an exit | |
2273 | event for each thread that exits, as expected. */ | |
2274 | thread_dead = 1; | |
2275 | if (debug_linux_nat) | |
2276 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2277 | target_pid_to_str (lp->ptid)); | |
2278 | } | |
432b4d03 JK |
2279 | if (pid != 0) |
2280 | break; | |
2281 | ||
2282 | /* Bugs 10970, 12702. | |
2283 | Thread group leader may have exited in which case we'll lock up in | |
2284 | waitpid if there are other threads, even if they are all zombies too. | |
2285 | Basically, we're not supposed to use waitpid this way. | |
2286 | __WCLONE is not applicable for the leader so we can't use that. | |
2287 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2288 | process; it gets ESRCH both for the zombie and for running processes. | |
2289 | ||
2290 | As a workaround, check if we're waiting for the thread group leader and | |
2291 | if it's a zombie, and avoid calling waitpid if it is. | |
2292 | ||
2293 | This is racy, what if the tgl becomes a zombie right after we check? | |
2294 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2295 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2296 | |
dfd4cc63 LM |
2297 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2298 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2299 | { |
d6b0e80f AC |
2300 | thread_dead = 1; |
2301 | if (debug_linux_nat) | |
432b4d03 JK |
2302 | fprintf_unfiltered (gdb_stdlog, |
2303 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2304 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2305 | break; |
d6b0e80f | 2306 | } |
432b4d03 JK |
2307 | |
2308 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2309 | get invoked despite our caller had them intentionally blocked by | |
2310 | block_child_signals. This is sensitive only to the loop of | |
2311 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2312 | again before it gets to sigsuspend so we can safely let the handlers | |
2313 | get executed here. */ | |
2314 | ||
2315 | sigsuspend (&suspend_mask); | |
2316 | } | |
2317 | ||
2318 | restore_child_signals_mask (&prev_mask); | |
2319 | ||
d6b0e80f AC |
2320 | if (!thread_dead) |
2321 | { | |
dfd4cc63 | 2322 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2323 | |
2324 | if (debug_linux_nat) | |
2325 | { | |
2326 | fprintf_unfiltered (gdb_stdlog, | |
2327 | "WL: waitpid %s received %s\n", | |
2328 | target_pid_to_str (lp->ptid), | |
2329 | status_to_str (status)); | |
2330 | } | |
d6b0e80f | 2331 | |
a9f4bb21 PA |
2332 | /* Check if the thread has exited. */ |
2333 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2334 | { | |
2335 | thread_dead = 1; | |
2336 | if (debug_linux_nat) | |
2337 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2338 | target_pid_to_str (lp->ptid)); | |
2339 | } | |
d6b0e80f AC |
2340 | } |
2341 | ||
2342 | if (thread_dead) | |
2343 | { | |
e26af52f | 2344 | exit_lwp (lp); |
d6b0e80f AC |
2345 | return 0; |
2346 | } | |
2347 | ||
2348 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2349 | lp->stopped = 1; |
d6b0e80f | 2350 | |
ca2163eb PA |
2351 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2352 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2353 | { | |
2354 | /* No longer need the sysgood bit. The ptrace event ends up | |
2355 | recorded in lp->waitstatus if we care for it. We can carry | |
2356 | on handling the event like a regular SIGTRAP from here | |
2357 | on. */ | |
2358 | status = W_STOPCODE (SIGTRAP); | |
2359 | if (linux_handle_syscall_trap (lp, 1)) | |
2360 | return wait_lwp (lp); | |
2361 | } | |
2362 | ||
d6b0e80f AC |
2363 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2364 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2365 | { | |
2366 | if (debug_linux_nat) | |
2367 | fprintf_unfiltered (gdb_stdlog, | |
2368 | "WL: Handling extended status 0x%06x\n", | |
2369 | status); | |
3d799a95 | 2370 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
2371 | return wait_lwp (lp); |
2372 | } | |
2373 | ||
2374 | return status; | |
2375 | } | |
2376 | ||
2377 | /* Send a SIGSTOP to LP. */ | |
2378 | ||
2379 | static int | |
2380 | stop_callback (struct lwp_info *lp, void *data) | |
2381 | { | |
2382 | if (!lp->stopped && !lp->signalled) | |
2383 | { | |
2384 | int ret; | |
2385 | ||
2386 | if (debug_linux_nat) | |
2387 | { | |
2388 | fprintf_unfiltered (gdb_stdlog, | |
2389 | "SC: kill %s **<SIGSTOP>**\n", | |
2390 | target_pid_to_str (lp->ptid)); | |
2391 | } | |
2392 | errno = 0; | |
dfd4cc63 | 2393 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2394 | if (debug_linux_nat) |
2395 | { | |
2396 | fprintf_unfiltered (gdb_stdlog, | |
2397 | "SC: lwp kill %d %s\n", | |
2398 | ret, | |
2399 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2400 | } | |
2401 | ||
2402 | lp->signalled = 1; | |
2403 | gdb_assert (lp->status == 0); | |
2404 | } | |
2405 | ||
2406 | return 0; | |
2407 | } | |
2408 | ||
7b50312a PA |
2409 | /* Request a stop on LWP. */ |
2410 | ||
2411 | void | |
2412 | linux_stop_lwp (struct lwp_info *lwp) | |
2413 | { | |
2414 | stop_callback (lwp, NULL); | |
2415 | } | |
2416 | ||
57380f4e | 2417 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2418 | |
2419 | static int | |
57380f4e DJ |
2420 | linux_nat_has_pending_sigint (int pid) |
2421 | { | |
2422 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2423 | |
2424 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2425 | ||
2426 | if (sigismember (&pending, SIGINT) | |
2427 | && !sigismember (&ignored, SIGINT)) | |
2428 | return 1; | |
2429 | ||
2430 | return 0; | |
2431 | } | |
2432 | ||
2433 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2434 | ||
2435 | static int | |
2436 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2437 | { |
57380f4e DJ |
2438 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2439 | flag to consume the next one. */ | |
2440 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2441 | && WSTOPSIG (lp->status) == SIGINT) | |
2442 | lp->status = 0; | |
2443 | else | |
2444 | lp->ignore_sigint = 1; | |
2445 | ||
2446 | return 0; | |
2447 | } | |
2448 | ||
2449 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2450 | This function is called after we know the LWP has stopped; if the LWP | |
2451 | stopped before the expected SIGINT was delivered, then it will never have | |
2452 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2453 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2454 | |
57380f4e DJ |
2455 | static void |
2456 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2457 | { | |
2458 | if (!lp->ignore_sigint) | |
2459 | return; | |
2460 | ||
dfd4cc63 | 2461 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2462 | { |
2463 | if (debug_linux_nat) | |
2464 | fprintf_unfiltered (gdb_stdlog, | |
2465 | "MCIS: Clearing bogus flag for %s\n", | |
2466 | target_pid_to_str (lp->ptid)); | |
2467 | lp->ignore_sigint = 0; | |
2468 | } | |
2469 | } | |
2470 | ||
ebec9a0f PA |
2471 | /* Fetch the possible triggered data watchpoint info and store it in |
2472 | LP. | |
2473 | ||
2474 | On some archs, like x86, that use debug registers to set | |
2475 | watchpoints, it's possible that the way to know which watched | |
2476 | address trapped, is to check the register that is used to select | |
2477 | which address to watch. Problem is, between setting the watchpoint | |
2478 | and reading back which data address trapped, the user may change | |
2479 | the set of watchpoints, and, as a consequence, GDB changes the | |
2480 | debug registers in the inferior. To avoid reading back a stale | |
2481 | stopped-data-address when that happens, we cache in LP the fact | |
2482 | that a watchpoint trapped, and the corresponding data address, as | |
2483 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2484 | registers meanwhile, we have the cached data we can rely on. */ | |
2485 | ||
2486 | static void | |
2487 | save_sigtrap (struct lwp_info *lp) | |
2488 | { | |
2489 | struct cleanup *old_chain; | |
2490 | ||
2491 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
2492 | { | |
2493 | lp->stopped_by_watchpoint = 0; | |
2494 | return; | |
2495 | } | |
2496 | ||
2497 | old_chain = save_inferior_ptid (); | |
2498 | inferior_ptid = lp->ptid; | |
2499 | ||
6a109b6b | 2500 | lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint (linux_ops); |
ebec9a0f PA |
2501 | |
2502 | if (lp->stopped_by_watchpoint) | |
2503 | { | |
2504 | if (linux_ops->to_stopped_data_address != NULL) | |
2505 | lp->stopped_data_address_p = | |
2506 | linux_ops->to_stopped_data_address (¤t_target, | |
2507 | &lp->stopped_data_address); | |
2508 | else | |
2509 | lp->stopped_data_address_p = 0; | |
2510 | } | |
2511 | ||
2512 | do_cleanups (old_chain); | |
2513 | } | |
2514 | ||
2515 | /* See save_sigtrap. */ | |
2516 | ||
2517 | static int | |
6a109b6b | 2518 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2519 | { |
2520 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2521 | ||
2522 | gdb_assert (lp != NULL); | |
2523 | ||
2524 | return lp->stopped_by_watchpoint; | |
2525 | } | |
2526 | ||
2527 | static int | |
2528 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2529 | { | |
2530 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2531 | ||
2532 | gdb_assert (lp != NULL); | |
2533 | ||
2534 | *addr_p = lp->stopped_data_address; | |
2535 | ||
2536 | return lp->stopped_data_address_p; | |
2537 | } | |
2538 | ||
26ab7092 JK |
2539 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2540 | ||
2541 | static int | |
2542 | sigtrap_is_event (int status) | |
2543 | { | |
2544 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2545 | } | |
2546 | ||
2547 | /* SIGTRAP-like events recognizer. */ | |
2548 | ||
2549 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
2550 | ||
00390b84 JK |
2551 | /* Check for SIGTRAP-like events in LP. */ |
2552 | ||
2553 | static int | |
2554 | linux_nat_lp_status_is_event (struct lwp_info *lp) | |
2555 | { | |
2556 | /* We check for lp->waitstatus in addition to lp->status, because we can | |
2557 | have pending process exits recorded in lp->status | |
2558 | and W_EXITCODE(0,0) == 0. We should probably have an additional | |
2559 | lp->status_p flag. */ | |
2560 | ||
2561 | return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE | |
2562 | && linux_nat_status_is_event (lp->status)); | |
2563 | } | |
2564 | ||
26ab7092 JK |
2565 | /* Set alternative SIGTRAP-like events recognizer. If |
2566 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2567 | applied. */ | |
2568 | ||
2569 | void | |
2570 | linux_nat_set_status_is_event (struct target_ops *t, | |
2571 | int (*status_is_event) (int status)) | |
2572 | { | |
2573 | linux_nat_status_is_event = status_is_event; | |
2574 | } | |
2575 | ||
57380f4e DJ |
2576 | /* Wait until LP is stopped. */ |
2577 | ||
2578 | static int | |
2579 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2580 | { | |
dfd4cc63 | 2581 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
6c95b8df PA |
2582 | |
2583 | /* If this is a vfork parent, bail out, it is not going to report | |
2584 | any SIGSTOP until the vfork is done with. */ | |
2585 | if (inf->vfork_child != NULL) | |
2586 | return 0; | |
2587 | ||
d6b0e80f AC |
2588 | if (!lp->stopped) |
2589 | { | |
2590 | int status; | |
2591 | ||
2592 | status = wait_lwp (lp); | |
2593 | if (status == 0) | |
2594 | return 0; | |
2595 | ||
57380f4e DJ |
2596 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2597 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2598 | { |
57380f4e | 2599 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2600 | |
2601 | errno = 0; | |
dfd4cc63 | 2602 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2603 | lp->stopped = 0; |
d6b0e80f AC |
2604 | if (debug_linux_nat) |
2605 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2606 | "PTRACE_CONT %s, 0, 0 (%s) " |
2607 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2608 | target_pid_to_str (lp->ptid), |
2609 | errno ? safe_strerror (errno) : "OK"); | |
2610 | ||
57380f4e | 2611 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2612 | } |
2613 | ||
57380f4e DJ |
2614 | maybe_clear_ignore_sigint (lp); |
2615 | ||
d6b0e80f AC |
2616 | if (WSTOPSIG (status) != SIGSTOP) |
2617 | { | |
e5ef252a | 2618 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2619 | |
e5ef252a PA |
2620 | save_sigtrap (lp); |
2621 | ||
2622 | if (debug_linux_nat) | |
2623 | fprintf_unfiltered (gdb_stdlog, | |
2624 | "SWC: Pending event %s in %s\n", | |
2625 | status_to_str ((int) status), | |
2626 | target_pid_to_str (lp->ptid)); | |
2627 | ||
2628 | /* Save the sigtrap event. */ | |
2629 | lp->status = status; | |
e5ef252a | 2630 | gdb_assert (lp->signalled); |
d6b0e80f AC |
2631 | } |
2632 | else | |
2633 | { | |
2634 | /* We caught the SIGSTOP that we intended to catch, so | |
2635 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2636 | |
2637 | if (debug_linux_nat) | |
2638 | fprintf_unfiltered (gdb_stdlog, | |
2639 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2640 | target_pid_to_str (lp->ptid)); | |
2641 | ||
e5ef252a PA |
2642 | /* Reset SIGNALLED only after the stop_wait_callback call |
2643 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2644 | lp->signalled = 0; |
2645 | } | |
2646 | } | |
2647 | ||
2648 | return 0; | |
2649 | } | |
2650 | ||
d6b0e80f AC |
2651 | /* Return non-zero if LP has a wait status pending. */ |
2652 | ||
2653 | static int | |
2654 | status_callback (struct lwp_info *lp, void *data) | |
2655 | { | |
2656 | /* Only report a pending wait status if we pretend that this has | |
2657 | indeed been resumed. */ | |
ca2163eb PA |
2658 | if (!lp->resumed) |
2659 | return 0; | |
2660 | ||
2661 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2662 | { | |
2663 | /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event, | |
766062f6 | 2664 | or a pending process exit. Note that `W_EXITCODE(0,0) == |
ca2163eb PA |
2665 | 0', so a clean process exit can not be stored pending in |
2666 | lp->status, it is indistinguishable from | |
2667 | no-pending-status. */ | |
2668 | return 1; | |
2669 | } | |
2670 | ||
2671 | if (lp->status != 0) | |
2672 | return 1; | |
2673 | ||
2674 | return 0; | |
d6b0e80f AC |
2675 | } |
2676 | ||
2677 | /* Return non-zero if LP isn't stopped. */ | |
2678 | ||
2679 | static int | |
2680 | running_callback (struct lwp_info *lp, void *data) | |
2681 | { | |
25289eb2 PA |
2682 | return (!lp->stopped |
2683 | || ((lp->status != 0 | |
2684 | || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2685 | && lp->resumed)); | |
d6b0e80f AC |
2686 | } |
2687 | ||
2688 | /* Count the LWP's that have had events. */ | |
2689 | ||
2690 | static int | |
2691 | count_events_callback (struct lwp_info *lp, void *data) | |
2692 | { | |
2693 | int *count = data; | |
2694 | ||
2695 | gdb_assert (count != NULL); | |
2696 | ||
e09490f1 | 2697 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2698 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2699 | (*count)++; |
2700 | ||
2701 | return 0; | |
2702 | } | |
2703 | ||
2704 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2705 | ||
2706 | static int | |
2707 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2708 | { | |
25289eb2 PA |
2709 | if (lp->last_resume_kind == resume_step |
2710 | && lp->status != 0) | |
d6b0e80f AC |
2711 | return 1; |
2712 | else | |
2713 | return 0; | |
2714 | } | |
2715 | ||
2716 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2717 | ||
2718 | static int | |
2719 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2720 | { | |
2721 | int *selector = data; | |
2722 | ||
2723 | gdb_assert (selector != NULL); | |
2724 | ||
1777feb0 | 2725 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2726 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2727 | if ((*selector)-- == 0) |
2728 | return 1; | |
2729 | ||
2730 | return 0; | |
2731 | } | |
2732 | ||
710151dd PA |
2733 | static int |
2734 | cancel_breakpoint (struct lwp_info *lp) | |
2735 | { | |
2736 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2737 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2738 | LWP. We will handle the current event, eventually we will resume | |
2739 | this LWP, and this breakpoint will trap again. | |
2740 | ||
2741 | If we do not do this, then we run the risk that the user will | |
2742 | delete or disable the breakpoint, but the LWP will have already | |
2743 | tripped on it. */ | |
2744 | ||
515630c5 UW |
2745 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2746 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2747 | CORE_ADDR pc; | |
2748 | ||
118e6252 | 2749 | pc = regcache_read_pc (regcache) - target_decr_pc_after_break (gdbarch); |
6c95b8df | 2750 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
710151dd PA |
2751 | { |
2752 | if (debug_linux_nat) | |
2753 | fprintf_unfiltered (gdb_stdlog, | |
2754 | "CB: Push back breakpoint for %s\n", | |
2755 | target_pid_to_str (lp->ptid)); | |
2756 | ||
2757 | /* Back up the PC if necessary. */ | |
118e6252 | 2758 | if (target_decr_pc_after_break (gdbarch)) |
515630c5 UW |
2759 | regcache_write_pc (regcache, pc); |
2760 | ||
710151dd PA |
2761 | return 1; |
2762 | } | |
2763 | return 0; | |
2764 | } | |
2765 | ||
d6b0e80f AC |
2766 | static int |
2767 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2768 | { | |
2769 | struct lwp_info *event_lp = data; | |
2770 | ||
2771 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2772 | if (lp == event_lp) | |
2773 | return 0; | |
2774 | ||
2775 | /* If a LWP other than the LWP that we're reporting an event for has | |
2776 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2777 | then just arrange for it to hit it again later. We don't keep | |
2778 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2779 | LWP. We will handle the current event, eventually we will resume | |
2780 | all LWPs, and this one will get its breakpoint trap again. | |
2781 | ||
2782 | If we do not do this, then we run the risk that the user will | |
2783 | delete or disable the breakpoint, but the LWP will have already | |
2784 | tripped on it. */ | |
2785 | ||
00390b84 | 2786 | if (linux_nat_lp_status_is_event (lp) |
710151dd PA |
2787 | && cancel_breakpoint (lp)) |
2788 | /* Throw away the SIGTRAP. */ | |
2789 | lp->status = 0; | |
d6b0e80f AC |
2790 | |
2791 | return 0; | |
2792 | } | |
2793 | ||
2794 | /* Select one LWP out of those that have events pending. */ | |
2795 | ||
2796 | static void | |
d90e17a7 | 2797 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2798 | { |
2799 | int num_events = 0; | |
2800 | int random_selector; | |
2801 | struct lwp_info *event_lp; | |
2802 | ||
ac264b3b | 2803 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2804 | (*orig_lp)->status = *status; |
2805 | ||
2806 | /* Give preference to any LWP that is being single-stepped. */ | |
d90e17a7 PA |
2807 | event_lp = iterate_over_lwps (filter, |
2808 | select_singlestep_lwp_callback, NULL); | |
d6b0e80f AC |
2809 | if (event_lp != NULL) |
2810 | { | |
2811 | if (debug_linux_nat) | |
2812 | fprintf_unfiltered (gdb_stdlog, | |
2813 | "SEL: Select single-step %s\n", | |
2814 | target_pid_to_str (event_lp->ptid)); | |
2815 | } | |
2816 | else | |
2817 | { | |
2818 | /* No single-stepping LWP. Select one at random, out of those | |
2819 | which have had SIGTRAP events. */ | |
2820 | ||
2821 | /* First see how many SIGTRAP events we have. */ | |
d90e17a7 | 2822 | iterate_over_lwps (filter, count_events_callback, &num_events); |
d6b0e80f AC |
2823 | |
2824 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2825 | random_selector = (int) | |
2826 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2827 | ||
2828 | if (debug_linux_nat && num_events > 1) | |
2829 | fprintf_unfiltered (gdb_stdlog, | |
2830 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2831 | num_events, random_selector); | |
2832 | ||
d90e17a7 PA |
2833 | event_lp = iterate_over_lwps (filter, |
2834 | select_event_lwp_callback, | |
d6b0e80f AC |
2835 | &random_selector); |
2836 | } | |
2837 | ||
2838 | if (event_lp != NULL) | |
2839 | { | |
2840 | /* Switch the event LWP. */ | |
2841 | *orig_lp = event_lp; | |
2842 | *status = event_lp->status; | |
2843 | } | |
2844 | ||
2845 | /* Flush the wait status for the event LWP. */ | |
2846 | (*orig_lp)->status = 0; | |
2847 | } | |
2848 | ||
2849 | /* Return non-zero if LP has been resumed. */ | |
2850 | ||
2851 | static int | |
2852 | resumed_callback (struct lwp_info *lp, void *data) | |
2853 | { | |
2854 | return lp->resumed; | |
2855 | } | |
2856 | ||
12d9289a PA |
2857 | /* Stop an active thread, verify it still exists, then resume it. If |
2858 | the thread ends up with a pending status, then it is not resumed, | |
2859 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2860 | |
2861 | static int | |
2862 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2863 | { | |
12d9289a PA |
2864 | int *new_pending_p = data; |
2865 | ||
25289eb2 | 2866 | if (!lp->stopped) |
d6b0e80f | 2867 | { |
25289eb2 PA |
2868 | ptid_t ptid = lp->ptid; |
2869 | ||
d6b0e80f AC |
2870 | stop_callback (lp, NULL); |
2871 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2872 | |
2873 | /* Resume if the lwp still exists, and the core wanted it | |
2874 | running. */ | |
12d9289a PA |
2875 | lp = find_lwp_pid (ptid); |
2876 | if (lp != NULL) | |
25289eb2 | 2877 | { |
12d9289a PA |
2878 | if (lp->last_resume_kind == resume_stop |
2879 | && lp->status == 0) | |
2880 | { | |
2881 | /* The core wanted the LWP to stop. Even if it stopped | |
2882 | cleanly (with SIGSTOP), leave the event pending. */ | |
2883 | if (debug_linux_nat) | |
2884 | fprintf_unfiltered (gdb_stdlog, | |
2885 | "SARC: core wanted LWP %ld stopped " | |
2886 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2887 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2888 | lp->status = W_STOPCODE (SIGSTOP); |
2889 | } | |
2890 | ||
2891 | if (lp->status == 0) | |
2892 | { | |
2893 | if (debug_linux_nat) | |
2894 | fprintf_unfiltered (gdb_stdlog, | |
2895 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2896 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2897 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2898 | } |
2899 | else | |
2900 | { | |
2901 | if (debug_linux_nat) | |
2902 | fprintf_unfiltered (gdb_stdlog, | |
2903 | "SARC: not re-resuming LWP %ld " | |
2904 | "(has pending)\n", | |
dfd4cc63 | 2905 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2906 | if (new_pending_p) |
2907 | *new_pending_p = 1; | |
2908 | } | |
25289eb2 | 2909 | } |
d6b0e80f AC |
2910 | } |
2911 | return 0; | |
2912 | } | |
2913 | ||
02f3fc28 | 2914 | /* Check if we should go on and pass this event to common code. |
12d9289a PA |
2915 | Return the affected lwp if we are, or NULL otherwise. If we stop |
2916 | all lwps temporarily, we may end up with new pending events in some | |
2917 | other lwp. In that case set *NEW_PENDING_P to true. */ | |
2918 | ||
02f3fc28 | 2919 | static struct lwp_info * |
0e5bf2a8 | 2920 | linux_nat_filter_event (int lwpid, int status, int *new_pending_p) |
02f3fc28 PA |
2921 | { |
2922 | struct lwp_info *lp; | |
2923 | ||
12d9289a PA |
2924 | *new_pending_p = 0; |
2925 | ||
02f3fc28 PA |
2926 | lp = find_lwp_pid (pid_to_ptid (lwpid)); |
2927 | ||
2928 | /* Check for stop events reported by a process we didn't already | |
2929 | know about - anything not already in our LWP list. | |
2930 | ||
2931 | If we're expecting to receive stopped processes after | |
2932 | fork, vfork, and clone events, then we'll just add the | |
2933 | new one to our list and go back to waiting for the event | |
2934 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2935 | from waitpid before or after the event is. |
2936 | ||
2937 | But note the case of a non-leader thread exec'ing after the | |
2938 | leader having exited, and gone from our lists. The non-leader | |
2939 | thread changes its tid to the tgid. */ | |
2940 | ||
2941 | if (WIFSTOPPED (status) && lp == NULL | |
2942 | && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC)) | |
2943 | { | |
2944 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2945 | if (debug_linux_nat) | |
2946 | fprintf_unfiltered (gdb_stdlog, | |
2947 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2948 | lwpid); | |
2949 | ||
dfd4cc63 | 2950 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2951 | lp->stopped = 1; |
2952 | lp->resumed = 1; | |
2953 | add_thread (lp->ptid); | |
2954 | } | |
2955 | ||
02f3fc28 PA |
2956 | if (WIFSTOPPED (status) && !lp) |
2957 | { | |
84636d28 | 2958 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2959 | return NULL; |
2960 | } | |
2961 | ||
2962 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2963 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2964 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2965 | exits. */ |
2966 | if (!WIFSTOPPED (status) && !lp) | |
2967 | return NULL; | |
2968 | ||
8817a6f2 PA |
2969 | /* This LWP is stopped now. (And if dead, this prevents it from |
2970 | ever being continued.) */ | |
2971 | lp->stopped = 1; | |
2972 | ||
ca2163eb PA |
2973 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2974 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2975 | { | |
2976 | /* No longer need the sysgood bit. The ptrace event ends up | |
2977 | recorded in lp->waitstatus if we care for it. We can carry | |
2978 | on handling the event like a regular SIGTRAP from here | |
2979 | on. */ | |
2980 | status = W_STOPCODE (SIGTRAP); | |
2981 | if (linux_handle_syscall_trap (lp, 0)) | |
2982 | return NULL; | |
2983 | } | |
02f3fc28 | 2984 | |
ca2163eb PA |
2985 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2986 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
02f3fc28 PA |
2987 | { |
2988 | if (debug_linux_nat) | |
2989 | fprintf_unfiltered (gdb_stdlog, | |
2990 | "LLW: Handling extended status 0x%06x\n", | |
2991 | status); | |
2992 | if (linux_handle_extended_wait (lp, status, 0)) | |
2993 | return NULL; | |
2994 | } | |
2995 | ||
26ab7092 | 2996 | if (linux_nat_status_is_event (status)) |
da559b09 | 2997 | save_sigtrap (lp); |
ca2163eb | 2998 | |
02f3fc28 | 2999 | /* Check if the thread has exited. */ |
d90e17a7 | 3000 | if ((WIFEXITED (status) || WIFSIGNALED (status)) |
dfd4cc63 | 3001 | && num_lwps (ptid_get_pid (lp->ptid)) > 1) |
02f3fc28 | 3002 | { |
9db03742 JB |
3003 | /* If this is the main thread, we must stop all threads and verify |
3004 | if they are still alive. This is because in the nptl thread model | |
3005 | on Linux 2.4, there is no signal issued for exiting LWPs | |
02f3fc28 PA |
3006 | other than the main thread. We only get the main thread exit |
3007 | signal once all child threads have already exited. If we | |
3008 | stop all the threads and use the stop_wait_callback to check | |
3009 | if they have exited we can determine whether this signal | |
3010 | should be ignored or whether it means the end of the debugged | |
3011 | application, regardless of which threading model is being | |
5d3b6af6 | 3012 | used. */ |
dfd4cc63 | 3013 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
02f3fc28 | 3014 | { |
dfd4cc63 | 3015 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), |
12d9289a | 3016 | stop_and_resume_callback, new_pending_p); |
02f3fc28 PA |
3017 | } |
3018 | ||
3019 | if (debug_linux_nat) | |
3020 | fprintf_unfiltered (gdb_stdlog, | |
3021 | "LLW: %s exited.\n", | |
3022 | target_pid_to_str (lp->ptid)); | |
3023 | ||
dfd4cc63 | 3024 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) |
9db03742 JB |
3025 | { |
3026 | /* If there is at least one more LWP, then the exit signal | |
3027 | was not the end of the debugged application and should be | |
3028 | ignored. */ | |
3029 | exit_lwp (lp); | |
3030 | return NULL; | |
3031 | } | |
02f3fc28 PA |
3032 | } |
3033 | ||
3034 | /* Check if the current LWP has previously exited. In the nptl | |
3035 | thread model, LWPs other than the main thread do not issue | |
3036 | signals when they exit so we must check whenever the thread has | |
3037 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3038 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3039 | { |
dfd4cc63 | 3040 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3041 | |
02f3fc28 PA |
3042 | if (debug_linux_nat) |
3043 | fprintf_unfiltered (gdb_stdlog, | |
3044 | "LLW: %s exited.\n", | |
3045 | target_pid_to_str (lp->ptid)); | |
3046 | ||
3047 | exit_lwp (lp); | |
3048 | ||
3049 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3050 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3051 | |
3052 | /* Discard the event. */ | |
3053 | return NULL; | |
3054 | } | |
3055 | ||
3056 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3057 | an attempt to stop an LWP. */ | |
3058 | if (lp->signalled | |
3059 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3060 | { | |
3061 | if (debug_linux_nat) | |
3062 | fprintf_unfiltered (gdb_stdlog, | |
3063 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3064 | target_pid_to_str (lp->ptid)); | |
3065 | ||
02f3fc28 PA |
3066 | lp->signalled = 0; |
3067 | ||
25289eb2 PA |
3068 | if (lp->last_resume_kind != resume_stop) |
3069 | { | |
3070 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3071 | |
25289eb2 PA |
3072 | registers_changed (); |
3073 | ||
7b50312a PA |
3074 | if (linux_nat_prepare_to_resume != NULL) |
3075 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3076 | linux_ops->to_resume (linux_ops, |
3077 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
3078 | lp->step, GDB_SIGNAL_0); | |
25289eb2 PA |
3079 | if (debug_linux_nat) |
3080 | fprintf_unfiltered (gdb_stdlog, | |
3081 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3082 | lp->step ? | |
3083 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3084 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3085 | |
25289eb2 PA |
3086 | lp->stopped = 0; |
3087 | gdb_assert (lp->resumed); | |
02f3fc28 | 3088 | |
25289eb2 PA |
3089 | /* Discard the event. */ |
3090 | return NULL; | |
3091 | } | |
02f3fc28 PA |
3092 | } |
3093 | ||
57380f4e DJ |
3094 | /* Make sure we don't report a SIGINT that we have already displayed |
3095 | for another thread. */ | |
3096 | if (lp->ignore_sigint | |
3097 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3098 | { | |
3099 | if (debug_linux_nat) | |
3100 | fprintf_unfiltered (gdb_stdlog, | |
3101 | "LLW: Delayed SIGINT caught for %s.\n", | |
3102 | target_pid_to_str (lp->ptid)); | |
3103 | ||
3104 | /* This is a delayed SIGINT. */ | |
3105 | lp->ignore_sigint = 0; | |
3106 | ||
3107 | registers_changed (); | |
7b50312a PA |
3108 | if (linux_nat_prepare_to_resume != NULL) |
3109 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3110 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3111 | lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3112 | if (debug_linux_nat) |
3113 | fprintf_unfiltered (gdb_stdlog, | |
3114 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3115 | lp->step ? | |
3116 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3117 | target_pid_to_str (lp->ptid)); | |
3118 | ||
3119 | lp->stopped = 0; | |
3120 | gdb_assert (lp->resumed); | |
3121 | ||
3122 | /* Discard the event. */ | |
3123 | return NULL; | |
3124 | } | |
3125 | ||
02f3fc28 PA |
3126 | /* An interesting event. */ |
3127 | gdb_assert (lp); | |
ca2163eb | 3128 | lp->status = status; |
02f3fc28 PA |
3129 | return lp; |
3130 | } | |
3131 | ||
0e5bf2a8 PA |
3132 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3133 | their exits until all other threads in the group have exited. */ | |
3134 | ||
3135 | static void | |
3136 | check_zombie_leaders (void) | |
3137 | { | |
3138 | struct inferior *inf; | |
3139 | ||
3140 | ALL_INFERIORS (inf) | |
3141 | { | |
3142 | struct lwp_info *leader_lp; | |
3143 | ||
3144 | if (inf->pid == 0) | |
3145 | continue; | |
3146 | ||
3147 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3148 | if (leader_lp != NULL | |
3149 | /* Check if there are other threads in the group, as we may | |
3150 | have raced with the inferior simply exiting. */ | |
3151 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3152 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3153 | { |
3154 | if (debug_linux_nat) | |
3155 | fprintf_unfiltered (gdb_stdlog, | |
3156 | "CZL: Thread group leader %d zombie " | |
3157 | "(it exited, or another thread execd).\n", | |
3158 | inf->pid); | |
3159 | ||
3160 | /* A leader zombie can mean one of two things: | |
3161 | ||
3162 | - It exited, and there's an exit status pending | |
3163 | available, or only the leader exited (not the whole | |
3164 | program). In the latter case, we can't waitpid the | |
3165 | leader's exit status until all other threads are gone. | |
3166 | ||
3167 | - There are 3 or more threads in the group, and a thread | |
3168 | other than the leader exec'd. On an exec, the Linux | |
3169 | kernel destroys all other threads (except the execing | |
3170 | one) in the thread group, and resets the execing thread's | |
3171 | tid to the tgid. No exit notification is sent for the | |
3172 | execing thread -- from the ptracer's perspective, it | |
3173 | appears as though the execing thread just vanishes. | |
3174 | Until we reap all other threads except the leader and the | |
3175 | execing thread, the leader will be zombie, and the | |
3176 | execing thread will be in `D (disc sleep)'. As soon as | |
3177 | all other threads are reaped, the execing thread changes | |
3178 | it's tid to the tgid, and the previous (zombie) leader | |
3179 | vanishes, giving place to the "new" leader. We could try | |
3180 | distinguishing the exit and exec cases, by waiting once | |
3181 | more, and seeing if something comes out, but it doesn't | |
3182 | sound useful. The previous leader _does_ go away, and | |
3183 | we'll re-add the new one once we see the exec event | |
3184 | (which is just the same as what would happen if the | |
3185 | previous leader did exit voluntarily before some other | |
3186 | thread execs). */ | |
3187 | ||
3188 | if (debug_linux_nat) | |
3189 | fprintf_unfiltered (gdb_stdlog, | |
3190 | "CZL: Thread group leader %d vanished.\n", | |
3191 | inf->pid); | |
3192 | exit_lwp (leader_lp); | |
3193 | } | |
3194 | } | |
3195 | } | |
3196 | ||
d6b0e80f | 3197 | static ptid_t |
7feb7d06 | 3198 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3199 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3200 | int target_options) | |
d6b0e80f | 3201 | { |
7feb7d06 | 3202 | static sigset_t prev_mask; |
4b60df3d | 3203 | enum resume_kind last_resume_kind; |
12d9289a | 3204 | struct lwp_info *lp; |
12d9289a | 3205 | int status; |
d6b0e80f | 3206 | |
01124a23 | 3207 | if (debug_linux_nat) |
b84876c2 PA |
3208 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3209 | ||
f973ed9c DJ |
3210 | /* The first time we get here after starting a new inferior, we may |
3211 | not have added it to the LWP list yet - this is the earliest | |
3212 | moment at which we know its PID. */ | |
d90e17a7 | 3213 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3214 | { |
27c9d204 PA |
3215 | /* Upgrade the main thread's ptid. */ |
3216 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3217 | ptid_build (ptid_get_pid (inferior_ptid), |
3218 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3219 | |
26cb8b7c | 3220 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3221 | lp->resumed = 1; |
3222 | } | |
3223 | ||
12696c10 | 3224 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3225 | block_child_signals (&prev_mask); |
d6b0e80f AC |
3226 | |
3227 | retry: | |
d90e17a7 PA |
3228 | lp = NULL; |
3229 | status = 0; | |
d6b0e80f AC |
3230 | |
3231 | /* First check if there is a LWP with a wait status pending. */ | |
0e5bf2a8 | 3232 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d6b0e80f | 3233 | { |
0e5bf2a8 | 3234 | /* Any LWP in the PTID group that's been resumed will do. */ |
d90e17a7 | 3235 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
d6b0e80f AC |
3236 | if (lp) |
3237 | { | |
ca2163eb | 3238 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3239 | fprintf_unfiltered (gdb_stdlog, |
3240 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3241 | status_to_str (lp->status), |
d6b0e80f AC |
3242 | target_pid_to_str (lp->ptid)); |
3243 | } | |
d6b0e80f | 3244 | } |
dfd4cc63 | 3245 | else if (ptid_lwp_p (ptid)) |
d6b0e80f AC |
3246 | { |
3247 | if (debug_linux_nat) | |
3248 | fprintf_unfiltered (gdb_stdlog, | |
3249 | "LLW: Waiting for specific LWP %s.\n", | |
3250 | target_pid_to_str (ptid)); | |
3251 | ||
3252 | /* We have a specific LWP to check. */ | |
3253 | lp = find_lwp_pid (ptid); | |
3254 | gdb_assert (lp); | |
d6b0e80f | 3255 | |
ca2163eb | 3256 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3257 | fprintf_unfiltered (gdb_stdlog, |
3258 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3259 | status_to_str (lp->status), |
d6b0e80f AC |
3260 | target_pid_to_str (lp->ptid)); |
3261 | ||
d90e17a7 PA |
3262 | /* We check for lp->waitstatus in addition to lp->status, |
3263 | because we can have pending process exits recorded in | |
3264 | lp->status and W_EXITCODE(0,0) == 0. We should probably have | |
3265 | an additional lp->status_p flag. */ | |
ca2163eb | 3266 | if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) |
d90e17a7 | 3267 | lp = NULL; |
d6b0e80f AC |
3268 | } |
3269 | ||
b84876c2 PA |
3270 | if (!target_can_async_p ()) |
3271 | { | |
3272 | /* Causes SIGINT to be passed on to the attached process. */ | |
3273 | set_sigint_trap (); | |
b84876c2 | 3274 | } |
d6b0e80f | 3275 | |
0e5bf2a8 | 3276 | /* But if we don't find a pending event, we'll have to wait. */ |
7feb7d06 | 3277 | |
d90e17a7 | 3278 | while (lp == NULL) |
d6b0e80f AC |
3279 | { |
3280 | pid_t lwpid; | |
3281 | ||
0e5bf2a8 PA |
3282 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3283 | quirks: | |
3284 | ||
3285 | - If the thread group leader exits while other threads in the | |
3286 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3287 | waitpid won't return an exit status until the other threads | |
3288 | in the group are reapped. | |
3289 | ||
3290 | - When a non-leader thread execs, that thread just vanishes | |
3291 | without reporting an exit (so we'd hang if we waited for it | |
3292 | explicitly in that case). The exec event is reported to | |
3293 | the TGID pid. */ | |
3294 | ||
3295 | errno = 0; | |
3296 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3297 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3298 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3299 | ||
3300 | if (debug_linux_nat) | |
3301 | fprintf_unfiltered (gdb_stdlog, | |
3302 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3303 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3304 | |
d6b0e80f AC |
3305 | if (lwpid > 0) |
3306 | { | |
12d9289a PA |
3307 | /* If this is true, then we paused LWPs momentarily, and may |
3308 | now have pending events to handle. */ | |
3309 | int new_pending; | |
3310 | ||
d6b0e80f AC |
3311 | if (debug_linux_nat) |
3312 | { | |
3313 | fprintf_unfiltered (gdb_stdlog, | |
3314 | "LLW: waitpid %ld received %s\n", | |
3315 | (long) lwpid, status_to_str (status)); | |
3316 | } | |
3317 | ||
0e5bf2a8 | 3318 | lp = linux_nat_filter_event (lwpid, status, &new_pending); |
d90e17a7 | 3319 | |
33355866 JK |
3320 | /* STATUS is now no longer valid, use LP->STATUS instead. */ |
3321 | status = 0; | |
3322 | ||
0e5bf2a8 | 3323 | if (lp && !ptid_match (lp->ptid, ptid)) |
d6b0e80f | 3324 | { |
e3e9f5a2 PA |
3325 | gdb_assert (lp->resumed); |
3326 | ||
d90e17a7 | 3327 | if (debug_linux_nat) |
3e43a32a MS |
3328 | fprintf (stderr, |
3329 | "LWP %ld got an event %06x, leaving pending.\n", | |
33355866 | 3330 | ptid_get_lwp (lp->ptid), lp->status); |
d90e17a7 | 3331 | |
ca2163eb | 3332 | if (WIFSTOPPED (lp->status)) |
d90e17a7 | 3333 | { |
ca2163eb | 3334 | if (WSTOPSIG (lp->status) != SIGSTOP) |
d90e17a7 | 3335 | { |
e3e9f5a2 PA |
3336 | /* Cancel breakpoint hits. The breakpoint may |
3337 | be removed before we fetch events from this | |
3338 | process to report to the core. It is best | |
3339 | not to assume the moribund breakpoints | |
3340 | heuristic always handles these cases --- it | |
3341 | could be too many events go through to the | |
3342 | core before this one is handled. All-stop | |
3343 | always cancels breakpoint hits in all | |
3344 | threads. */ | |
3345 | if (non_stop | |
00390b84 | 3346 | && linux_nat_lp_status_is_event (lp) |
e3e9f5a2 PA |
3347 | && cancel_breakpoint (lp)) |
3348 | { | |
3349 | /* Throw away the SIGTRAP. */ | |
3350 | lp->status = 0; | |
3351 | ||
3352 | if (debug_linux_nat) | |
3353 | fprintf (stderr, | |
3e43a32a MS |
3354 | "LLW: LWP %ld hit a breakpoint while" |
3355 | " waiting for another process;" | |
3356 | " cancelled it\n", | |
e3e9f5a2 PA |
3357 | ptid_get_lwp (lp->ptid)); |
3358 | } | |
d90e17a7 PA |
3359 | } |
3360 | else | |
8817a6f2 | 3361 | lp->signalled = 0; |
d90e17a7 | 3362 | } |
33355866 | 3363 | else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status)) |
d90e17a7 PA |
3364 | { |
3365 | if (debug_linux_nat) | |
3e43a32a MS |
3366 | fprintf (stderr, |
3367 | "Process %ld exited while stopping LWPs\n", | |
d90e17a7 PA |
3368 | ptid_get_lwp (lp->ptid)); |
3369 | ||
3370 | /* This was the last lwp in the process. Since | |
3371 | events are serialized to GDB core, and we can't | |
3372 | report this one right now, but GDB core and the | |
3373 | other target layers will want to be notified | |
3374 | about the exit code/signal, leave the status | |
3375 | pending for the next time we're able to report | |
3376 | it. */ | |
d90e17a7 | 3377 | |
d90e17a7 PA |
3378 | /* Dead LWP's aren't expected to reported a pending |
3379 | sigstop. */ | |
3380 | lp->signalled = 0; | |
3381 | ||
3382 | /* Store the pending event in the waitstatus as | |
3383 | well, because W_EXITCODE(0,0) == 0. */ | |
ca2163eb | 3384 | store_waitstatus (&lp->waitstatus, lp->status); |
d90e17a7 PA |
3385 | } |
3386 | ||
3387 | /* Keep looking. */ | |
3388 | lp = NULL; | |
d6b0e80f AC |
3389 | } |
3390 | ||
0e5bf2a8 | 3391 | if (new_pending) |
d90e17a7 | 3392 | { |
0e5bf2a8 PA |
3393 | /* Some LWP now has a pending event. Go all the way |
3394 | back to check it. */ | |
3395 | goto retry; | |
3396 | } | |
12d9289a | 3397 | |
0e5bf2a8 PA |
3398 | if (lp) |
3399 | { | |
3400 | /* We got an event to report to the core. */ | |
3401 | break; | |
d90e17a7 | 3402 | } |
0e5bf2a8 PA |
3403 | |
3404 | /* Retry until nothing comes out of waitpid. A single | |
3405 | SIGCHLD can indicate more than one child stopped. */ | |
3406 | continue; | |
d6b0e80f AC |
3407 | } |
3408 | ||
0e5bf2a8 PA |
3409 | /* Check for zombie thread group leaders. Those can't be reaped |
3410 | until all other threads in the thread group are. */ | |
3411 | check_zombie_leaders (); | |
d6b0e80f | 3412 | |
0e5bf2a8 PA |
3413 | /* If there are no resumed children left, bail. We'd be stuck |
3414 | forever in the sigsuspend call below otherwise. */ | |
3415 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3416 | { | |
3417 | if (debug_linux_nat) | |
3418 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3419 | |
0e5bf2a8 | 3420 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3421 | |
0e5bf2a8 PA |
3422 | if (!target_can_async_p ()) |
3423 | clear_sigint_trap (); | |
b84876c2 | 3424 | |
0e5bf2a8 PA |
3425 | restore_child_signals_mask (&prev_mask); |
3426 | return minus_one_ptid; | |
d6b0e80f | 3427 | } |
28736962 | 3428 | |
0e5bf2a8 PA |
3429 | /* No interesting event to report to the core. */ |
3430 | ||
3431 | if (target_options & TARGET_WNOHANG) | |
3432 | { | |
01124a23 | 3433 | if (debug_linux_nat) |
28736962 PA |
3434 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3435 | ||
0e5bf2a8 | 3436 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3437 | restore_child_signals_mask (&prev_mask); |
3438 | return minus_one_ptid; | |
3439 | } | |
d6b0e80f AC |
3440 | |
3441 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3442 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3443 | |
3444 | /* Block until we get an event reported with SIGCHLD. */ | |
3445 | sigsuspend (&suspend_mask); | |
d6b0e80f AC |
3446 | } |
3447 | ||
b84876c2 | 3448 | if (!target_can_async_p ()) |
d26b5354 | 3449 | clear_sigint_trap (); |
d6b0e80f AC |
3450 | |
3451 | gdb_assert (lp); | |
3452 | ||
ca2163eb PA |
3453 | status = lp->status; |
3454 | lp->status = 0; | |
3455 | ||
d6b0e80f AC |
3456 | /* Don't report signals that GDB isn't interested in, such as |
3457 | signals that are neither printed nor stopped upon. Stopping all | |
3458 | threads can be a bit time-consuming so if we want decent | |
3459 | performance with heavily multi-threaded programs, especially when | |
3460 | they're using a high frequency timer, we'd better avoid it if we | |
3461 | can. */ | |
3462 | ||
3463 | if (WIFSTOPPED (status)) | |
3464 | { | |
2ea28649 | 3465 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); |
d6b0e80f | 3466 | |
2455069d UW |
3467 | /* When using hardware single-step, we need to report every signal. |
3468 | Otherwise, signals in pass_mask may be short-circuited. */ | |
d539ed7e | 3469 | if (!lp->step |
2455069d | 3470 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))) |
d6b0e80f AC |
3471 | { |
3472 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
3473 | here? It is not clear we should. GDB may not expect | |
3474 | other threads to run. On the other hand, not resuming | |
3475 | newly attached threads may cause an unwanted delay in | |
3476 | getting them running. */ | |
3477 | registers_changed (); | |
7b50312a PA |
3478 | if (linux_nat_prepare_to_resume != NULL) |
3479 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3480 | linux_ops->to_resume (linux_ops, |
3481 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
10d6c8cd | 3482 | lp->step, signo); |
d6b0e80f AC |
3483 | if (debug_linux_nat) |
3484 | fprintf_unfiltered (gdb_stdlog, | |
3485 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3486 | lp->step ? | |
3487 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3488 | target_pid_to_str (lp->ptid), | |
a493e3e2 | 3489 | (signo != GDB_SIGNAL_0 |
2ea28649 | 3490 | ? strsignal (gdb_signal_to_host (signo)) |
423ec54c | 3491 | : "0")); |
d6b0e80f | 3492 | lp->stopped = 0; |
d6b0e80f AC |
3493 | goto retry; |
3494 | } | |
3495 | ||
1ad15515 | 3496 | if (!non_stop) |
d6b0e80f | 3497 | { |
1ad15515 PA |
3498 | /* Only do the below in all-stop, as we currently use SIGINT |
3499 | to implement target_stop (see linux_nat_stop) in | |
3500 | non-stop. */ | |
a493e3e2 | 3501 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) |
1ad15515 PA |
3502 | { |
3503 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3504 | forwarded to the entire process group, that is, all LWPs | |
3505 | will receive it - unless they're using CLONE_THREAD to | |
3506 | share signals. Since we only want to report it once, we | |
3507 | mark it as ignored for all LWPs except this one. */ | |
d90e17a7 PA |
3508 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)), |
3509 | set_ignore_sigint, NULL); | |
1ad15515 PA |
3510 | lp->ignore_sigint = 0; |
3511 | } | |
3512 | else | |
3513 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
3514 | } |
3515 | } | |
3516 | ||
3517 | /* This LWP is stopped now. */ | |
3518 | lp->stopped = 1; | |
3519 | ||
3520 | if (debug_linux_nat) | |
3521 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
3522 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
3523 | ||
4c28f408 PA |
3524 | if (!non_stop) |
3525 | { | |
3526 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3527 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3528 | |
3529 | /* ... and wait until all of them have reported back that | |
3530 | they're no longer running. */ | |
d90e17a7 | 3531 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
4c28f408 PA |
3532 | |
3533 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3534 | from among those that have had events. Giving equal priority | |
3535 | to all LWPs that have had events helps prevent | |
3536 | starvation. */ | |
0e5bf2a8 | 3537 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d90e17a7 | 3538 | select_event_lwp (ptid, &lp, &status); |
d6b0e80f | 3539 | |
e3e9f5a2 PA |
3540 | /* Now that we've selected our final event LWP, cancel any |
3541 | breakpoints in other LWPs that have hit a GDB breakpoint. | |
3542 | See the comment in cancel_breakpoints_callback to find out | |
3543 | why. */ | |
3544 | iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp); | |
3545 | ||
4b60df3d PA |
3546 | /* We'll need this to determine whether to report a SIGSTOP as |
3547 | TARGET_WAITKIND_0. Need to take a copy because | |
3548 | resume_clear_callback clears it. */ | |
3549 | last_resume_kind = lp->last_resume_kind; | |
3550 | ||
e3e9f5a2 PA |
3551 | /* In all-stop, from the core's perspective, all LWPs are now |
3552 | stopped until a new resume action is sent over. */ | |
3553 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3554 | } | |
3555 | else | |
25289eb2 | 3556 | { |
4b60df3d PA |
3557 | /* See above. */ |
3558 | last_resume_kind = lp->last_resume_kind; | |
3559 | resume_clear_callback (lp, NULL); | |
25289eb2 | 3560 | } |
d6b0e80f | 3561 | |
26ab7092 | 3562 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3563 | { |
d6b0e80f AC |
3564 | if (debug_linux_nat) |
3565 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3566 | "LLW: trap ptid is %s.\n", |
3567 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3568 | } |
d6b0e80f AC |
3569 | |
3570 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3571 | { | |
3572 | *ourstatus = lp->waitstatus; | |
3573 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3574 | } | |
3575 | else | |
3576 | store_waitstatus (ourstatus, status); | |
3577 | ||
01124a23 | 3578 | if (debug_linux_nat) |
b84876c2 PA |
3579 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3580 | ||
7feb7d06 | 3581 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3582 | |
4b60df3d | 3583 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3584 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3585 | && WSTOPSIG (status) == SIGSTOP) | |
3586 | { | |
3587 | /* A thread that has been requested to stop by GDB with | |
3588 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3589 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3590 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3591 | } |
3592 | ||
1e225492 JK |
3593 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3594 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3595 | lp->core = -1; | |
3596 | else | |
2e794194 | 3597 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3598 | |
f973ed9c | 3599 | return lp->ptid; |
d6b0e80f AC |
3600 | } |
3601 | ||
e3e9f5a2 PA |
3602 | /* Resume LWPs that are currently stopped without any pending status |
3603 | to report, but are resumed from the core's perspective. */ | |
3604 | ||
3605 | static int | |
3606 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3607 | { | |
3608 | ptid_t *wait_ptid_p = data; | |
3609 | ||
3610 | if (lp->stopped | |
3611 | && lp->resumed | |
3612 | && lp->status == 0 | |
3613 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
3614 | { | |
336060f3 PA |
3615 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3616 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
3617 | CORE_ADDR pc = regcache_read_pc (regcache); | |
3618 | ||
e3e9f5a2 PA |
3619 | gdb_assert (is_executing (lp->ptid)); |
3620 | ||
3621 | /* Don't bother if there's a breakpoint at PC that we'd hit | |
3622 | immediately, and we're not waiting for this LWP. */ | |
3623 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3624 | { | |
e3e9f5a2 PA |
3625 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
3626 | return 0; | |
3627 | } | |
3628 | ||
3629 | if (debug_linux_nat) | |
3630 | fprintf_unfiltered (gdb_stdlog, | |
336060f3 PA |
3631 | "RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", |
3632 | target_pid_to_str (lp->ptid), | |
3633 | paddress (gdbarch, pc), | |
3634 | lp->step); | |
e3e9f5a2 | 3635 | |
336060f3 | 3636 | registers_changed (); |
7b50312a PA |
3637 | if (linux_nat_prepare_to_resume != NULL) |
3638 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3639 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3640 | lp->step, GDB_SIGNAL_0); |
e3e9f5a2 | 3641 | lp->stopped = 0; |
e3e9f5a2 PA |
3642 | lp->stopped_by_watchpoint = 0; |
3643 | } | |
3644 | ||
3645 | return 0; | |
3646 | } | |
3647 | ||
7feb7d06 PA |
3648 | static ptid_t |
3649 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3650 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3651 | int target_options) | |
7feb7d06 PA |
3652 | { |
3653 | ptid_t event_ptid; | |
3654 | ||
3655 | if (debug_linux_nat) | |
09826ec5 PA |
3656 | { |
3657 | char *options_string; | |
3658 | ||
3659 | options_string = target_options_to_string (target_options); | |
3660 | fprintf_unfiltered (gdb_stdlog, | |
3661 | "linux_nat_wait: [%s], [%s]\n", | |
3662 | target_pid_to_str (ptid), | |
3663 | options_string); | |
3664 | xfree (options_string); | |
3665 | } | |
7feb7d06 PA |
3666 | |
3667 | /* Flush the async file first. */ | |
3668 | if (target_can_async_p ()) | |
3669 | async_file_flush (); | |
3670 | ||
e3e9f5a2 PA |
3671 | /* Resume LWPs that are currently stopped without any pending status |
3672 | to report, but are resumed from the core's perspective. LWPs get | |
3673 | in this state if we find them stopping at a time we're not | |
3674 | interested in reporting the event (target_wait on a | |
3675 | specific_process, for example, see linux_nat_wait_1), and | |
3676 | meanwhile the event became uninteresting. Don't bother resuming | |
3677 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3678 | if (non_stop) | |
3679 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3680 | ||
47608cb1 | 3681 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3682 | |
3683 | /* If we requested any event, and something came out, assume there | |
3684 | may be more. If we requested a specific lwp or process, also | |
3685 | assume there may be more. */ | |
3686 | if (target_can_async_p () | |
6953d224 PA |
3687 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3688 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3689 | || !ptid_equal (ptid, minus_one_ptid))) |
3690 | async_file_mark (); | |
3691 | ||
3692 | /* Get ready for the next event. */ | |
3693 | if (target_can_async_p ()) | |
3694 | target_async (inferior_event_handler, 0); | |
3695 | ||
3696 | return event_ptid; | |
3697 | } | |
3698 | ||
d6b0e80f AC |
3699 | static int |
3700 | kill_callback (struct lwp_info *lp, void *data) | |
3701 | { | |
ed731959 JK |
3702 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3703 | ||
3704 | errno = 0; | |
69ff6be5 | 3705 | kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 | 3706 | if (debug_linux_nat) |
57745c90 PA |
3707 | { |
3708 | int save_errno = errno; | |
3709 | ||
3710 | fprintf_unfiltered (gdb_stdlog, | |
3711 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3712 | target_pid_to_str (lp->ptid), | |
3713 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3714 | } | |
ed731959 JK |
3715 | |
3716 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3717 | ||
d6b0e80f | 3718 | errno = 0; |
dfd4cc63 | 3719 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f | 3720 | if (debug_linux_nat) |
57745c90 PA |
3721 | { |
3722 | int save_errno = errno; | |
3723 | ||
3724 | fprintf_unfiltered (gdb_stdlog, | |
3725 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3726 | target_pid_to_str (lp->ptid), | |
3727 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3728 | } | |
d6b0e80f AC |
3729 | |
3730 | return 0; | |
3731 | } | |
3732 | ||
3733 | static int | |
3734 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3735 | { | |
3736 | pid_t pid; | |
3737 | ||
3738 | /* We must make sure that there are no pending events (delayed | |
3739 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3740 | program doesn't interfere with any following debugging session. */ | |
3741 | ||
3742 | /* For cloned processes we must check both with __WCLONE and | |
3743 | without, since the exit status of a cloned process isn't reported | |
3744 | with __WCLONE. */ | |
3745 | if (lp->cloned) | |
3746 | { | |
3747 | do | |
3748 | { | |
dfd4cc63 | 3749 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3750 | if (pid != (pid_t) -1) |
d6b0e80f | 3751 | { |
e85a822c DJ |
3752 | if (debug_linux_nat) |
3753 | fprintf_unfiltered (gdb_stdlog, | |
3754 | "KWC: wait %s received unknown.\n", | |
3755 | target_pid_to_str (lp->ptid)); | |
3756 | /* The Linux kernel sometimes fails to kill a thread | |
3757 | completely after PTRACE_KILL; that goes from the stop | |
3758 | point in do_fork out to the one in | |
3759 | get_signal_to_deliever and waits again. So kill it | |
3760 | again. */ | |
3761 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3762 | } |
3763 | } | |
dfd4cc63 | 3764 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3765 | |
3766 | gdb_assert (pid == -1 && errno == ECHILD); | |
3767 | } | |
3768 | ||
3769 | do | |
3770 | { | |
dfd4cc63 | 3771 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3772 | if (pid != (pid_t) -1) |
d6b0e80f | 3773 | { |
e85a822c DJ |
3774 | if (debug_linux_nat) |
3775 | fprintf_unfiltered (gdb_stdlog, | |
3776 | "KWC: wait %s received unk.\n", | |
3777 | target_pid_to_str (lp->ptid)); | |
3778 | /* See the call to kill_callback above. */ | |
3779 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3780 | } |
3781 | } | |
dfd4cc63 | 3782 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3783 | |
3784 | gdb_assert (pid == -1 && errno == ECHILD); | |
3785 | return 0; | |
3786 | } | |
3787 | ||
3788 | static void | |
7d85a9c0 | 3789 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3790 | { |
f973ed9c DJ |
3791 | struct target_waitstatus last; |
3792 | ptid_t last_ptid; | |
3793 | int status; | |
d6b0e80f | 3794 | |
f973ed9c DJ |
3795 | /* If we're stopped while forking and we haven't followed yet, |
3796 | kill the other task. We need to do this first because the | |
3797 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3798 | |
f973ed9c | 3799 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3800 | |
f973ed9c DJ |
3801 | if (last.kind == TARGET_WAITKIND_FORKED |
3802 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3803 | { | |
dfd4cc63 | 3804 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3805 | wait (&status); |
26cb8b7c PA |
3806 | |
3807 | /* Let the arch-specific native code know this process is | |
3808 | gone. */ | |
dfd4cc63 | 3809 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3810 | } |
3811 | ||
3812 | if (forks_exist_p ()) | |
7feb7d06 | 3813 | linux_fork_killall (); |
f973ed9c DJ |
3814 | else |
3815 | { | |
d90e17a7 | 3816 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3817 | |
4c28f408 PA |
3818 | /* Stop all threads before killing them, since ptrace requires |
3819 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3820 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3821 | /* ... and wait until all of them have reported back that |
3822 | they're no longer running. */ | |
d90e17a7 | 3823 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3824 | |
f973ed9c | 3825 | /* Kill all LWP's ... */ |
d90e17a7 | 3826 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3827 | |
3828 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3829 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3830 | } |
3831 | ||
3832 | target_mourn_inferior (); | |
d6b0e80f AC |
3833 | } |
3834 | ||
3835 | static void | |
136d6dae | 3836 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3837 | { |
26cb8b7c PA |
3838 | int pid = ptid_get_pid (inferior_ptid); |
3839 | ||
3840 | purge_lwp_list (pid); | |
d6b0e80f | 3841 | |
f973ed9c | 3842 | if (! forks_exist_p ()) |
d90e17a7 PA |
3843 | /* Normal case, no other forks available. */ |
3844 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3845 | else |
3846 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3847 | there are other viable forks to debug. Delete the exiting | |
3848 | one and context-switch to the first available. */ | |
3849 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3850 | |
3851 | /* Let the arch-specific native code know this process is gone. */ | |
3852 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3853 | } |
3854 | ||
5b009018 PA |
3855 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3856 | layout of the inferiors' architecture. */ | |
3857 | ||
3858 | static void | |
a5362b9a | 3859 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3860 | { |
3861 | int done = 0; | |
3862 | ||
3863 | if (linux_nat_siginfo_fixup != NULL) | |
3864 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3865 | ||
3866 | /* If there was no callback, or the callback didn't do anything, | |
3867 | then just do a straight memcpy. */ | |
3868 | if (!done) | |
3869 | { | |
3870 | if (direction == 1) | |
a5362b9a | 3871 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3872 | else |
a5362b9a | 3873 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3874 | } |
3875 | } | |
3876 | ||
9b409511 | 3877 | static enum target_xfer_status |
4aa995e1 PA |
3878 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3879 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3880 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3881 | ULONGEST *xfered_len) | |
4aa995e1 | 3882 | { |
4aa995e1 | 3883 | int pid; |
a5362b9a TS |
3884 | siginfo_t siginfo; |
3885 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3886 | |
3887 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3888 | gdb_assert (readbuf || writebuf); | |
3889 | ||
dfd4cc63 | 3890 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3891 | if (pid == 0) |
dfd4cc63 | 3892 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3893 | |
3894 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3895 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3896 | |
3897 | errno = 0; | |
3898 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3899 | if (errno != 0) | |
2ed4b548 | 3900 | return TARGET_XFER_E_IO; |
4aa995e1 | 3901 | |
5b009018 PA |
3902 | /* When GDB is built as a 64-bit application, ptrace writes into |
3903 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3904 | inferior with a 64-bit GDB should look the same as debugging it | |
3905 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3906 | the converted layout, so any read/write will have to be done | |
3907 | post-conversion. */ | |
3908 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3909 | ||
4aa995e1 PA |
3910 | if (offset + len > sizeof (siginfo)) |
3911 | len = sizeof (siginfo) - offset; | |
3912 | ||
3913 | if (readbuf != NULL) | |
5b009018 | 3914 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3915 | else |
3916 | { | |
5b009018 PA |
3917 | memcpy (inf_siginfo + offset, writebuf, len); |
3918 | ||
3919 | /* Convert back to ptrace layout before flushing it out. */ | |
3920 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3921 | ||
4aa995e1 PA |
3922 | errno = 0; |
3923 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3924 | if (errno != 0) | |
2ed4b548 | 3925 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3926 | } |
3927 | ||
9b409511 YQ |
3928 | *xfered_len = len; |
3929 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3930 | } |
3931 | ||
9b409511 | 3932 | static enum target_xfer_status |
10d6c8cd DJ |
3933 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3934 | const char *annex, gdb_byte *readbuf, | |
3935 | const gdb_byte *writebuf, | |
9b409511 | 3936 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3937 | { |
4aa995e1 | 3938 | struct cleanup *old_chain; |
9b409511 | 3939 | enum target_xfer_status xfer; |
d6b0e80f | 3940 | |
4aa995e1 PA |
3941 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3942 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3943 | offset, len, xfered_len); |
4aa995e1 | 3944 | |
c35b1492 PA |
3945 | /* The target is connected but no live inferior is selected. Pass |
3946 | this request down to a lower stratum (e.g., the executable | |
3947 | file). */ | |
3948 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 3949 | return TARGET_XFER_EOF; |
c35b1492 | 3950 | |
4aa995e1 PA |
3951 | old_chain = save_inferior_ptid (); |
3952 | ||
dfd4cc63 LM |
3953 | if (ptid_lwp_p (inferior_ptid)) |
3954 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3955 | |
10d6c8cd | 3956 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3957 | offset, len, xfered_len); |
d6b0e80f AC |
3958 | |
3959 | do_cleanups (old_chain); | |
3960 | return xfer; | |
3961 | } | |
3962 | ||
3963 | static int | |
28439f5e | 3964 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3965 | { |
8c6a60d1 | 3966 | int err, tmp_errno; |
4c28f408 | 3967 | |
dfd4cc63 | 3968 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3969 | |
4c28f408 PA |
3970 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3971 | running thread errors out claiming that the thread doesn't | |
3972 | exist. */ | |
dfd4cc63 | 3973 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3974 | tmp_errno = errno; |
d6b0e80f AC |
3975 | if (debug_linux_nat) |
3976 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3977 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3978 | target_pid_to_str (ptid), |
8c6a60d1 | 3979 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3980 | |
4c28f408 | 3981 | if (err != 0) |
d6b0e80f AC |
3982 | return 0; |
3983 | ||
3984 | return 1; | |
3985 | } | |
3986 | ||
28439f5e PA |
3987 | static int |
3988 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3989 | { | |
3990 | return linux_thread_alive (ptid); | |
3991 | } | |
3992 | ||
d6b0e80f | 3993 | static char * |
117de6a9 | 3994 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3995 | { |
3996 | static char buf[64]; | |
3997 | ||
dfd4cc63 LM |
3998 | if (ptid_lwp_p (ptid) |
3999 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
4000 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 4001 | { |
dfd4cc63 | 4002 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
4003 | return buf; |
4004 | } | |
4005 | ||
4006 | return normal_pid_to_str (ptid); | |
4007 | } | |
4008 | ||
4694da01 | 4009 | static char * |
503a628d | 4010 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 TT |
4011 | { |
4012 | int pid = ptid_get_pid (thr->ptid); | |
4013 | long lwp = ptid_get_lwp (thr->ptid); | |
4014 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4015 | char buf[sizeof (FORMAT) + 30]; | |
4016 | FILE *comm_file; | |
4017 | char *result = NULL; | |
4018 | ||
4019 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4020 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4021 | if (comm_file) |
4022 | { | |
4023 | /* Not exported by the kernel, so we define it here. */ | |
4024 | #define COMM_LEN 16 | |
4025 | static char line[COMM_LEN + 1]; | |
4026 | ||
4027 | if (fgets (line, sizeof (line), comm_file)) | |
4028 | { | |
4029 | char *nl = strchr (line, '\n'); | |
4030 | ||
4031 | if (nl) | |
4032 | *nl = '\0'; | |
4033 | if (*line != '\0') | |
4034 | result = line; | |
4035 | } | |
4036 | ||
4037 | fclose (comm_file); | |
4038 | } | |
4039 | ||
4040 | #undef COMM_LEN | |
4041 | #undef FORMAT | |
4042 | ||
4043 | return result; | |
4044 | } | |
4045 | ||
dba24537 AC |
4046 | /* Accepts an integer PID; Returns a string representing a file that |
4047 | can be opened to get the symbols for the child process. */ | |
4048 | ||
6d8fd2b7 | 4049 | static char * |
8dd27370 | 4050 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 4051 | { |
b4ab256d HZ |
4052 | static char buf[PATH_MAX]; |
4053 | char name[PATH_MAX]; | |
dba24537 | 4054 | |
b4ab256d HZ |
4055 | xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid); |
4056 | memset (buf, 0, PATH_MAX); | |
4057 | if (readlink (name, buf, PATH_MAX - 1) <= 0) | |
4058 | strcpy (buf, name); | |
dba24537 | 4059 | |
b4ab256d | 4060 | return buf; |
dba24537 AC |
4061 | } |
4062 | ||
dba24537 AC |
4063 | /* Records the thread's register state for the corefile note |
4064 | section. */ | |
4065 | ||
4066 | static char * | |
6432734d UW |
4067 | linux_nat_collect_thread_registers (const struct regcache *regcache, |
4068 | ptid_t ptid, bfd *obfd, | |
4069 | char *note_data, int *note_size, | |
2ea28649 | 4070 | enum gdb_signal stop_signal) |
dba24537 | 4071 | { |
6432734d | 4072 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
4f844a66 | 4073 | const struct regset *regset; |
55e969c1 | 4074 | int core_regset_p; |
6432734d UW |
4075 | gdb_gregset_t gregs; |
4076 | gdb_fpregset_t fpregs; | |
4f844a66 DM |
4077 | |
4078 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
dba24537 | 4079 | |
6432734d UW |
4080 | if (core_regset_p |
4081 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
4082 | sizeof (gregs))) | |
4083 | != NULL && regset->collect_regset != NULL) | |
4084 | regset->collect_regset (regset, regcache, -1, &gregs, sizeof (gregs)); | |
4f844a66 | 4085 | else |
6432734d | 4086 | fill_gregset (regcache, &gregs, -1); |
2f2241f1 | 4087 | |
6432734d UW |
4088 | note_data = (char *) elfcore_write_prstatus |
4089 | (obfd, note_data, note_size, ptid_get_lwp (ptid), | |
2ea28649 | 4090 | gdb_signal_to_host (stop_signal), &gregs); |
2f2241f1 | 4091 | |
6432734d UW |
4092 | if (core_regset_p |
4093 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
4094 | sizeof (fpregs))) | |
3e43a32a | 4095 | != NULL && regset->collect_regset != NULL) |
6432734d UW |
4096 | regset->collect_regset (regset, regcache, -1, &fpregs, sizeof (fpregs)); |
4097 | else | |
4098 | fill_fpregset (regcache, &fpregs, -1); | |
17ea7499 | 4099 | |
6432734d UW |
4100 | note_data = (char *) elfcore_write_prfpreg (obfd, note_data, note_size, |
4101 | &fpregs, sizeof (fpregs)); | |
4f844a66 | 4102 | |
dba24537 AC |
4103 | return note_data; |
4104 | } | |
4105 | ||
dba24537 AC |
4106 | /* Fills the "to_make_corefile_note" target vector. Builds the note |
4107 | section for a corefile, and returns it in a malloc buffer. */ | |
4108 | ||
4109 | static char * | |
fc6691b2 TT |
4110 | linux_nat_make_corefile_notes (struct target_ops *self, |
4111 | bfd *obfd, int *note_size) | |
dba24537 | 4112 | { |
6432734d UW |
4113 | /* FIXME: uweigand/2011-10-06: Once all GNU/Linux architectures have been |
4114 | converted to gdbarch_core_regset_sections, this function can go away. */ | |
f5656ead | 4115 | return linux_make_corefile_notes (target_gdbarch (), obfd, note_size, |
6432734d | 4116 | linux_nat_collect_thread_registers); |
dba24537 AC |
4117 | } |
4118 | ||
10d6c8cd DJ |
4119 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4120 | filesystem. Because we can use a single read() call for /proc, this | |
4121 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4122 | but it doesn't support writes. */ | |
4123 | ||
9b409511 | 4124 | static enum target_xfer_status |
10d6c8cd DJ |
4125 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
4126 | const char *annex, gdb_byte *readbuf, | |
4127 | const gdb_byte *writebuf, | |
9b409511 | 4128 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 4129 | { |
10d6c8cd DJ |
4130 | LONGEST ret; |
4131 | int fd; | |
dba24537 AC |
4132 | char filename[64]; |
4133 | ||
10d6c8cd | 4134 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4135 | return 0; |
4136 | ||
4137 | /* Don't bother for one word. */ | |
4138 | if (len < 3 * sizeof (long)) | |
9b409511 | 4139 | return TARGET_XFER_EOF; |
dba24537 AC |
4140 | |
4141 | /* We could keep this file open and cache it - possibly one per | |
4142 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4143 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4144 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4145 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 4146 | if (fd == -1) |
9b409511 | 4147 | return TARGET_XFER_EOF; |
dba24537 AC |
4148 | |
4149 | /* If pread64 is available, use it. It's faster if the kernel | |
4150 | supports it (only one syscall), and it's 64-bit safe even on | |
4151 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4152 | application). */ | |
4153 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4154 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4155 | #else |
10d6c8cd | 4156 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4157 | #endif |
4158 | ret = 0; | |
4159 | else | |
4160 | ret = len; | |
4161 | ||
4162 | close (fd); | |
9b409511 YQ |
4163 | |
4164 | if (ret == 0) | |
4165 | return TARGET_XFER_EOF; | |
4166 | else | |
4167 | { | |
4168 | *xfered_len = ret; | |
4169 | return TARGET_XFER_OK; | |
4170 | } | |
dba24537 AC |
4171 | } |
4172 | ||
efcbbd14 UW |
4173 | |
4174 | /* Enumerate spufs IDs for process PID. */ | |
4175 | static LONGEST | |
b55e14c7 | 4176 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4177 | { |
f5656ead | 4178 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4179 | LONGEST pos = 0; |
4180 | LONGEST written = 0; | |
4181 | char path[128]; | |
4182 | DIR *dir; | |
4183 | struct dirent *entry; | |
4184 | ||
4185 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4186 | dir = opendir (path); | |
4187 | if (!dir) | |
4188 | return -1; | |
4189 | ||
4190 | rewinddir (dir); | |
4191 | while ((entry = readdir (dir)) != NULL) | |
4192 | { | |
4193 | struct stat st; | |
4194 | struct statfs stfs; | |
4195 | int fd; | |
4196 | ||
4197 | fd = atoi (entry->d_name); | |
4198 | if (!fd) | |
4199 | continue; | |
4200 | ||
4201 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4202 | if (stat (path, &st) != 0) | |
4203 | continue; | |
4204 | if (!S_ISDIR (st.st_mode)) | |
4205 | continue; | |
4206 | ||
4207 | if (statfs (path, &stfs) != 0) | |
4208 | continue; | |
4209 | if (stfs.f_type != SPUFS_MAGIC) | |
4210 | continue; | |
4211 | ||
4212 | if (pos >= offset && pos + 4 <= offset + len) | |
4213 | { | |
4214 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4215 | written += 4; | |
4216 | } | |
4217 | pos += 4; | |
4218 | } | |
4219 | ||
4220 | closedir (dir); | |
4221 | return written; | |
4222 | } | |
4223 | ||
4224 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4225 | object type, using the /proc file system. */ | |
9b409511 YQ |
4226 | |
4227 | static enum target_xfer_status | |
efcbbd14 UW |
4228 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4229 | const char *annex, gdb_byte *readbuf, | |
4230 | const gdb_byte *writebuf, | |
9b409511 | 4231 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4232 | { |
4233 | char buf[128]; | |
4234 | int fd = 0; | |
4235 | int ret = -1; | |
dfd4cc63 | 4236 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4237 | |
4238 | if (!annex) | |
4239 | { | |
4240 | if (!readbuf) | |
2ed4b548 | 4241 | return TARGET_XFER_E_IO; |
efcbbd14 | 4242 | else |
9b409511 YQ |
4243 | { |
4244 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4245 | ||
4246 | if (l < 0) | |
4247 | return TARGET_XFER_E_IO; | |
4248 | else if (l == 0) | |
4249 | return TARGET_XFER_EOF; | |
4250 | else | |
4251 | { | |
4252 | *xfered_len = (ULONGEST) l; | |
4253 | return TARGET_XFER_OK; | |
4254 | } | |
4255 | } | |
efcbbd14 UW |
4256 | } |
4257 | ||
4258 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4259 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4260 | if (fd <= 0) |
2ed4b548 | 4261 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4262 | |
4263 | if (offset != 0 | |
4264 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4265 | { | |
4266 | close (fd); | |
9b409511 | 4267 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4268 | } |
4269 | ||
4270 | if (writebuf) | |
4271 | ret = write (fd, writebuf, (size_t) len); | |
4272 | else if (readbuf) | |
4273 | ret = read (fd, readbuf, (size_t) len); | |
4274 | ||
4275 | close (fd); | |
9b409511 YQ |
4276 | |
4277 | if (ret < 0) | |
4278 | return TARGET_XFER_E_IO; | |
4279 | else if (ret == 0) | |
4280 | return TARGET_XFER_EOF; | |
4281 | else | |
4282 | { | |
4283 | *xfered_len = (ULONGEST) ret; | |
4284 | return TARGET_XFER_OK; | |
4285 | } | |
efcbbd14 UW |
4286 | } |
4287 | ||
4288 | ||
dba24537 AC |
4289 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4290 | ||
4291 | static void | |
4292 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4293 | { | |
4294 | int len = strlen (line) - 1; | |
4295 | const char *p; | |
4296 | int signum; | |
4297 | ||
4298 | if (line[len] != '\n') | |
8a3fe4f8 | 4299 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4300 | |
4301 | p = line; | |
4302 | signum = len * 4; | |
4303 | while (len-- > 0) | |
4304 | { | |
4305 | int digit; | |
4306 | ||
4307 | if (*p >= '0' && *p <= '9') | |
4308 | digit = *p - '0'; | |
4309 | else if (*p >= 'a' && *p <= 'f') | |
4310 | digit = *p - 'a' + 10; | |
4311 | else | |
8a3fe4f8 | 4312 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4313 | |
4314 | signum -= 4; | |
4315 | ||
4316 | if (digit & 1) | |
4317 | sigaddset (sigs, signum + 1); | |
4318 | if (digit & 2) | |
4319 | sigaddset (sigs, signum + 2); | |
4320 | if (digit & 4) | |
4321 | sigaddset (sigs, signum + 3); | |
4322 | if (digit & 8) | |
4323 | sigaddset (sigs, signum + 4); | |
4324 | ||
4325 | p++; | |
4326 | } | |
4327 | } | |
4328 | ||
4329 | /* Find process PID's pending signals from /proc/pid/status and set | |
4330 | SIGS to match. */ | |
4331 | ||
4332 | void | |
3e43a32a MS |
4333 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4334 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4335 | { |
4336 | FILE *procfile; | |
d8d2a3ee | 4337 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4338 | struct cleanup *cleanup; |
dba24537 AC |
4339 | |
4340 | sigemptyset (pending); | |
4341 | sigemptyset (blocked); | |
4342 | sigemptyset (ignored); | |
cde33bf1 | 4343 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4344 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4345 | if (procfile == NULL) |
8a3fe4f8 | 4346 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4347 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4348 | |
d8d2a3ee | 4349 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4350 | { |
4351 | /* Normal queued signals are on the SigPnd line in the status | |
4352 | file. However, 2.6 kernels also have a "shared" pending | |
4353 | queue for delivering signals to a thread group, so check for | |
4354 | a ShdPnd line also. | |
4355 | ||
4356 | Unfortunately some Red Hat kernels include the shared pending | |
4357 | queue but not the ShdPnd status field. */ | |
4358 | ||
4359 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
4360 | add_line_to_sigset (buffer + 8, pending); | |
4361 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
4362 | add_line_to_sigset (buffer + 8, pending); | |
4363 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
4364 | add_line_to_sigset (buffer + 8, blocked); | |
4365 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
4366 | add_line_to_sigset (buffer + 8, ignored); | |
4367 | } | |
4368 | ||
7c8a8b04 | 4369 | do_cleanups (cleanup); |
dba24537 AC |
4370 | } |
4371 | ||
9b409511 | 4372 | static enum target_xfer_status |
07e059b5 | 4373 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4374 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4375 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4376 | ULONGEST *xfered_len) | |
07e059b5 | 4377 | { |
07e059b5 VP |
4378 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4379 | ||
9b409511 YQ |
4380 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4381 | if (*xfered_len == 0) | |
4382 | return TARGET_XFER_EOF; | |
4383 | else | |
4384 | return TARGET_XFER_OK; | |
07e059b5 VP |
4385 | } |
4386 | ||
9b409511 | 4387 | static enum target_xfer_status |
10d6c8cd DJ |
4388 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4389 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4390 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4391 | ULONGEST *xfered_len) | |
10d6c8cd | 4392 | { |
9b409511 | 4393 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4394 | |
4395 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4396 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4397 | offset, len, xfered_len); |
10d6c8cd | 4398 | |
07e059b5 VP |
4399 | if (object == TARGET_OBJECT_OSDATA) |
4400 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4401 | offset, len, xfered_len); |
07e059b5 | 4402 | |
efcbbd14 UW |
4403 | if (object == TARGET_OBJECT_SPU) |
4404 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4405 | offset, len, xfered_len); |
efcbbd14 | 4406 | |
8f313923 JK |
4407 | /* GDB calculates all the addresses in possibly larget width of the address. |
4408 | Address width needs to be masked before its final use - either by | |
4409 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4410 | ||
4411 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4412 | ||
4413 | if (object == TARGET_OBJECT_MEMORY) | |
4414 | { | |
f5656ead | 4415 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4416 | |
4417 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4418 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4419 | } | |
4420 | ||
10d6c8cd | 4421 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4422 | offset, len, xfered_len); |
4423 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4424 | return xfer; |
4425 | ||
4426 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4427 | offset, len, xfered_len); |
10d6c8cd DJ |
4428 | } |
4429 | ||
5808517f YQ |
4430 | static void |
4431 | cleanup_target_stop (void *arg) | |
4432 | { | |
4433 | ptid_t *ptid = (ptid_t *) arg; | |
4434 | ||
4435 | gdb_assert (arg != NULL); | |
4436 | ||
4437 | /* Unpause all */ | |
a493e3e2 | 4438 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4439 | } |
4440 | ||
4441 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4442 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4443 | const char *strid) | |
5808517f YQ |
4444 | { |
4445 | char s[IPA_CMD_BUF_SIZE]; | |
4446 | struct cleanup *old_chain; | |
4447 | int pid = ptid_get_pid (inferior_ptid); | |
4448 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4449 | struct static_tracepoint_marker *marker = NULL; | |
4450 | char *p = s; | |
4451 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4452 | ||
4453 | /* Pause all */ | |
4454 | target_stop (ptid); | |
4455 | ||
4456 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4457 | s[sizeof ("qTfSTM")] = 0; | |
4458 | ||
42476b70 | 4459 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4460 | |
4461 | old_chain = make_cleanup (free_current_marker, &marker); | |
4462 | make_cleanup (cleanup_target_stop, &ptid); | |
4463 | ||
4464 | while (*p++ == 'm') | |
4465 | { | |
4466 | if (marker == NULL) | |
4467 | marker = XCNEW (struct static_tracepoint_marker); | |
4468 | ||
4469 | do | |
4470 | { | |
4471 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4472 | ||
4473 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4474 | { | |
4475 | VEC_safe_push (static_tracepoint_marker_p, | |
4476 | markers, marker); | |
4477 | marker = NULL; | |
4478 | } | |
4479 | else | |
4480 | { | |
4481 | release_static_tracepoint_marker (marker); | |
4482 | memset (marker, 0, sizeof (*marker)); | |
4483 | } | |
4484 | } | |
4485 | while (*p++ == ','); /* comma-separated list */ | |
4486 | ||
4487 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4488 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4489 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4490 | p = s; |
4491 | } | |
4492 | ||
4493 | do_cleanups (old_chain); | |
4494 | ||
4495 | return markers; | |
4496 | } | |
4497 | ||
e9efe249 | 4498 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4499 | it with local methods. */ |
4500 | ||
910122bf UW |
4501 | static void |
4502 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4503 | { |
6d8fd2b7 | 4504 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4505 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4506 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4507 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4508 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4509 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4510 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4511 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4512 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4513 | t->to_post_attach = linux_child_post_attach; |
4514 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4515 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; |
4516 | ||
4517 | super_xfer_partial = t->to_xfer_partial; | |
4518 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4519 | |
4520 | t->to_static_tracepoint_markers_by_strid | |
4521 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4522 | } |
4523 | ||
4524 | struct target_ops * | |
4525 | linux_target (void) | |
4526 | { | |
4527 | struct target_ops *t; | |
4528 | ||
4529 | t = inf_ptrace_target (); | |
4530 | linux_target_install_ops (t); | |
4531 | ||
4532 | return t; | |
4533 | } | |
4534 | ||
4535 | struct target_ops * | |
7714d83a | 4536 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4537 | { |
4538 | struct target_ops *t; | |
4539 | ||
4540 | t = inf_ptrace_trad_target (register_u_offset); | |
4541 | linux_target_install_ops (t); | |
10d6c8cd | 4542 | |
10d6c8cd DJ |
4543 | return t; |
4544 | } | |
4545 | ||
b84876c2 PA |
4546 | /* target_is_async_p implementation. */ |
4547 | ||
4548 | static int | |
6a109b6b | 4549 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 PA |
4550 | { |
4551 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4552 | it explicitly with the "set target-async" command. |
b84876c2 | 4553 | Someday, linux will always be async. */ |
3dd5b83d | 4554 | return target_async_permitted; |
b84876c2 PA |
4555 | } |
4556 | ||
4557 | /* target_can_async_p implementation. */ | |
4558 | ||
4559 | static int | |
6a109b6b | 4560 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4561 | { |
4562 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4563 | it explicitly with the "set target-async" command. |
b84876c2 | 4564 | Someday, linux will always be async. */ |
3dd5b83d | 4565 | return target_async_permitted; |
b84876c2 PA |
4566 | } |
4567 | ||
9908b566 | 4568 | static int |
2a9a2795 | 4569 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4570 | { |
4571 | return 1; | |
4572 | } | |
4573 | ||
d90e17a7 PA |
4574 | /* True if we want to support multi-process. To be removed when GDB |
4575 | supports multi-exec. */ | |
4576 | ||
2277426b | 4577 | int linux_multi_process = 1; |
d90e17a7 PA |
4578 | |
4579 | static int | |
86ce2668 | 4580 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4581 | { |
4582 | return linux_multi_process; | |
4583 | } | |
4584 | ||
03583c20 | 4585 | static int |
2bfc0540 | 4586 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4587 | { |
4588 | #ifdef HAVE_PERSONALITY | |
4589 | return 1; | |
4590 | #else | |
4591 | return 0; | |
4592 | #endif | |
4593 | } | |
4594 | ||
b84876c2 PA |
4595 | static int async_terminal_is_ours = 1; |
4596 | ||
4d4ca2a1 DE |
4597 | /* target_terminal_inferior implementation. |
4598 | ||
4599 | This is a wrapper around child_terminal_inferior to add async support. */ | |
b84876c2 PA |
4600 | |
4601 | static void | |
d2f640d4 | 4602 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 PA |
4603 | { |
4604 | if (!target_is_async_p ()) | |
4605 | { | |
4606 | /* Async mode is disabled. */ | |
d6b64346 | 4607 | child_terminal_inferior (self); |
b84876c2 PA |
4608 | return; |
4609 | } | |
4610 | ||
d6b64346 | 4611 | child_terminal_inferior (self); |
b84876c2 | 4612 | |
d9d2d8b6 | 4613 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4614 | if (!async_terminal_is_ours) |
4615 | return; | |
4616 | ||
4617 | delete_file_handler (input_fd); | |
4618 | async_terminal_is_ours = 0; | |
4619 | set_sigint_trap (); | |
4620 | } | |
4621 | ||
4d4ca2a1 DE |
4622 | /* target_terminal_ours implementation. |
4623 | ||
4624 | This is a wrapper around child_terminal_ours to add async support (and | |
4625 | implement the target_terminal_ours vs target_terminal_ours_for_output | |
4626 | distinction). child_terminal_ours is currently no different than | |
4627 | child_terminal_ours_for_output. | |
4628 | We leave target_terminal_ours_for_output alone, leaving it to | |
4629 | child_terminal_ours_for_output. */ | |
b84876c2 | 4630 | |
2c0b251b | 4631 | static void |
e3594fd1 | 4632 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 PA |
4633 | { |
4634 | if (!target_is_async_p ()) | |
4635 | { | |
4636 | /* Async mode is disabled. */ | |
d6b64346 | 4637 | child_terminal_ours (self); |
b84876c2 PA |
4638 | return; |
4639 | } | |
4640 | ||
4641 | /* GDB should never give the terminal to the inferior if the | |
4642 | inferior is running in the background (run&, continue&, etc.), | |
4643 | but claiming it sure should. */ | |
d6b64346 | 4644 | child_terminal_ours (self); |
b84876c2 | 4645 | |
b84876c2 PA |
4646 | if (async_terminal_is_ours) |
4647 | return; | |
4648 | ||
4649 | clear_sigint_trap (); | |
4650 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4651 | async_terminal_is_ours = 1; | |
4652 | } | |
4653 | ||
4654 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4655 | void *context); | |
4656 | static void *async_client_context; | |
4657 | ||
7feb7d06 PA |
4658 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4659 | so we notice when any child changes state, and notify the | |
4660 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4661 | above to wait for the arrival of a SIGCHLD. */ | |
4662 | ||
b84876c2 | 4663 | static void |
7feb7d06 | 4664 | sigchld_handler (int signo) |
b84876c2 | 4665 | { |
7feb7d06 PA |
4666 | int old_errno = errno; |
4667 | ||
01124a23 DE |
4668 | if (debug_linux_nat) |
4669 | ui_file_write_async_safe (gdb_stdlog, | |
4670 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4671 | |
4672 | if (signo == SIGCHLD | |
4673 | && linux_nat_event_pipe[0] != -1) | |
4674 | async_file_mark (); /* Let the event loop know that there are | |
4675 | events to handle. */ | |
4676 | ||
4677 | errno = old_errno; | |
4678 | } | |
4679 | ||
4680 | /* Callback registered with the target events file descriptor. */ | |
4681 | ||
4682 | static void | |
4683 | handle_target_event (int error, gdb_client_data client_data) | |
4684 | { | |
4685 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4686 | } | |
4687 | ||
4688 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4689 | ||
4690 | static int | |
4691 | linux_async_pipe (int enable) | |
4692 | { | |
4693 | int previous = (linux_nat_event_pipe[0] != -1); | |
4694 | ||
4695 | if (previous != enable) | |
4696 | { | |
4697 | sigset_t prev_mask; | |
4698 | ||
12696c10 PA |
4699 | /* Block child signals while we create/destroy the pipe, as |
4700 | their handler writes to it. */ | |
7feb7d06 PA |
4701 | block_child_signals (&prev_mask); |
4702 | ||
4703 | if (enable) | |
4704 | { | |
614c279d | 4705 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4706 | internal_error (__FILE__, __LINE__, |
4707 | "creating event pipe failed."); | |
4708 | ||
4709 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4710 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4711 | } | |
4712 | else | |
4713 | { | |
4714 | close (linux_nat_event_pipe[0]); | |
4715 | close (linux_nat_event_pipe[1]); | |
4716 | linux_nat_event_pipe[0] = -1; | |
4717 | linux_nat_event_pipe[1] = -1; | |
4718 | } | |
4719 | ||
4720 | restore_child_signals_mask (&prev_mask); | |
4721 | } | |
4722 | ||
4723 | return previous; | |
b84876c2 PA |
4724 | } |
4725 | ||
4726 | /* target_async implementation. */ | |
4727 | ||
4728 | static void | |
6a109b6b TT |
4729 | linux_nat_async (struct target_ops *ops, |
4730 | void (*callback) (enum inferior_event_type event_type, | |
4731 | void *context), | |
4732 | void *context) | |
b84876c2 | 4733 | { |
b84876c2 PA |
4734 | if (callback != NULL) |
4735 | { | |
4736 | async_client_callback = callback; | |
4737 | async_client_context = context; | |
7feb7d06 PA |
4738 | if (!linux_async_pipe (1)) |
4739 | { | |
4740 | add_file_handler (linux_nat_event_pipe[0], | |
4741 | handle_target_event, NULL); | |
4742 | /* There may be pending events to handle. Tell the event loop | |
4743 | to poll them. */ | |
4744 | async_file_mark (); | |
4745 | } | |
b84876c2 PA |
4746 | } |
4747 | else | |
4748 | { | |
4749 | async_client_callback = callback; | |
4750 | async_client_context = context; | |
b84876c2 | 4751 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4752 | linux_async_pipe (0); |
b84876c2 PA |
4753 | } |
4754 | return; | |
4755 | } | |
4756 | ||
a493e3e2 | 4757 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4758 | event came out. */ |
4759 | ||
4c28f408 | 4760 | static int |
252fbfc8 | 4761 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4762 | { |
d90e17a7 | 4763 | if (!lwp->stopped) |
252fbfc8 | 4764 | { |
d90e17a7 PA |
4765 | if (debug_linux_nat) |
4766 | fprintf_unfiltered (gdb_stdlog, | |
4767 | "LNSL: running -> suspending %s\n", | |
4768 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4769 | |
252fbfc8 | 4770 | |
25289eb2 PA |
4771 | if (lwp->last_resume_kind == resume_stop) |
4772 | { | |
4773 | if (debug_linux_nat) | |
4774 | fprintf_unfiltered (gdb_stdlog, | |
4775 | "linux-nat: already stopping LWP %ld at " | |
4776 | "GDB's request\n", | |
4777 | ptid_get_lwp (lwp->ptid)); | |
4778 | return 0; | |
4779 | } | |
252fbfc8 | 4780 | |
25289eb2 PA |
4781 | stop_callback (lwp, NULL); |
4782 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4783 | } |
4784 | else | |
4785 | { | |
4786 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4787 | |
d90e17a7 PA |
4788 | if (debug_linux_nat) |
4789 | { | |
e09875d4 | 4790 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4791 | fprintf_unfiltered (gdb_stdlog, |
4792 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4793 | target_pid_to_str (lwp->ptid)); |
4794 | else | |
3e43a32a MS |
4795 | fprintf_unfiltered (gdb_stdlog, |
4796 | "LNSL: already stopped/no " | |
4797 | "stop_requested yet %s\n", | |
d90e17a7 | 4798 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4799 | } |
4800 | } | |
4c28f408 PA |
4801 | return 0; |
4802 | } | |
4803 | ||
4804 | static void | |
1eab8a48 | 4805 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 PA |
4806 | { |
4807 | if (non_stop) | |
d90e17a7 | 4808 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4809 | else |
1eab8a48 | 4810 | linux_ops->to_stop (linux_ops, ptid); |
4c28f408 PA |
4811 | } |
4812 | ||
d90e17a7 | 4813 | static void |
de90e03d | 4814 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4815 | { |
4816 | /* Unregister from the event loop. */ | |
6a109b6b TT |
4817 | if (linux_nat_is_async_p (NULL)) |
4818 | linux_nat_async (NULL, NULL, 0); | |
d90e17a7 | 4819 | |
d90e17a7 | 4820 | if (linux_ops->to_close) |
de90e03d | 4821 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4822 | |
4823 | super_close (self); | |
d90e17a7 PA |
4824 | } |
4825 | ||
c0694254 PA |
4826 | /* When requests are passed down from the linux-nat layer to the |
4827 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4828 | used. The address space pointer is stored in the inferior object, | |
4829 | but the common code that is passed such ptid can't tell whether | |
4830 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4831 | look up the "main" process id from the lwp here. */ | |
4832 | ||
70221824 | 4833 | static struct address_space * |
c0694254 PA |
4834 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4835 | { | |
4836 | struct lwp_info *lwp; | |
4837 | struct inferior *inf; | |
4838 | int pid; | |
4839 | ||
dfd4cc63 LM |
4840 | pid = ptid_get_lwp (ptid); |
4841 | if (ptid_get_lwp (ptid) == 0) | |
c0694254 PA |
4842 | { |
4843 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4844 | tgid. */ | |
4845 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4846 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4847 | } |
4848 | else | |
4849 | { | |
4850 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4851 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4852 | } |
4853 | ||
4854 | inf = find_inferior_pid (pid); | |
4855 | gdb_assert (inf != NULL); | |
4856 | return inf->aspace; | |
4857 | } | |
4858 | ||
dc146f7c VP |
4859 | /* Return the cached value of the processor core for thread PTID. */ |
4860 | ||
70221824 | 4861 | static int |
dc146f7c VP |
4862 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4863 | { | |
4864 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4865 | |
dc146f7c VP |
4866 | if (info) |
4867 | return info->core; | |
4868 | return -1; | |
4869 | } | |
4870 | ||
f973ed9c DJ |
4871 | void |
4872 | linux_nat_add_target (struct target_ops *t) | |
4873 | { | |
f973ed9c DJ |
4874 | /* Save the provided single-threaded target. We save this in a separate |
4875 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4876 | may have saved a pointer to T; we want to use it for the final | |
4877 | process stratum target. */ | |
4878 | linux_ops_saved = *t; | |
4879 | linux_ops = &linux_ops_saved; | |
4880 | ||
4881 | /* Override some methods for multithreading. */ | |
b84876c2 | 4882 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4883 | t->to_attach = linux_nat_attach; |
4884 | t->to_detach = linux_nat_detach; | |
4885 | t->to_resume = linux_nat_resume; | |
4886 | t->to_wait = linux_nat_wait; | |
2455069d | 4887 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4888 | t->to_xfer_partial = linux_nat_xfer_partial; |
4889 | t->to_kill = linux_nat_kill; | |
4890 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4891 | t->to_thread_alive = linux_nat_thread_alive; | |
4892 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4893 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4894 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4895 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4896 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4897 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
f973ed9c | 4898 | |
b84876c2 PA |
4899 | t->to_can_async_p = linux_nat_can_async_p; |
4900 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4901 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4902 | t->to_async = linux_nat_async; |
b84876c2 PA |
4903 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4904 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4905 | |
4906 | super_close = t->to_close; | |
d90e17a7 | 4907 | t->to_close = linux_nat_close; |
b84876c2 | 4908 | |
4c28f408 PA |
4909 | /* Methods for non-stop support. */ |
4910 | t->to_stop = linux_nat_stop; | |
4911 | ||
d90e17a7 PA |
4912 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4913 | ||
03583c20 UW |
4914 | t->to_supports_disable_randomization |
4915 | = linux_nat_supports_disable_randomization; | |
4916 | ||
dc146f7c VP |
4917 | t->to_core_of_thread = linux_nat_core_of_thread; |
4918 | ||
f973ed9c DJ |
4919 | /* We don't change the stratum; this target will sit at |
4920 | process_stratum and thread_db will set at thread_stratum. This | |
4921 | is a little strange, since this is a multi-threaded-capable | |
4922 | target, but we want to be on the stack below thread_db, and we | |
4923 | also want to be used for single-threaded processes. */ | |
4924 | ||
4925 | add_target (t); | |
f973ed9c DJ |
4926 | } |
4927 | ||
9f0bdab8 DJ |
4928 | /* Register a method to call whenever a new thread is attached. */ |
4929 | void | |
7b50312a PA |
4930 | linux_nat_set_new_thread (struct target_ops *t, |
4931 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4932 | { |
4933 | /* Save the pointer. We only support a single registered instance | |
4934 | of the GNU/Linux native target, so we do not need to map this to | |
4935 | T. */ | |
4936 | linux_nat_new_thread = new_thread; | |
4937 | } | |
4938 | ||
26cb8b7c PA |
4939 | /* See declaration in linux-nat.h. */ |
4940 | ||
4941 | void | |
4942 | linux_nat_set_new_fork (struct target_ops *t, | |
4943 | linux_nat_new_fork_ftype *new_fork) | |
4944 | { | |
4945 | /* Save the pointer. */ | |
4946 | linux_nat_new_fork = new_fork; | |
4947 | } | |
4948 | ||
4949 | /* See declaration in linux-nat.h. */ | |
4950 | ||
4951 | void | |
4952 | linux_nat_set_forget_process (struct target_ops *t, | |
4953 | linux_nat_forget_process_ftype *fn) | |
4954 | { | |
4955 | /* Save the pointer. */ | |
4956 | linux_nat_forget_process_hook = fn; | |
4957 | } | |
4958 | ||
4959 | /* See declaration in linux-nat.h. */ | |
4960 | ||
4961 | void | |
4962 | linux_nat_forget_process (pid_t pid) | |
4963 | { | |
4964 | if (linux_nat_forget_process_hook != NULL) | |
4965 | linux_nat_forget_process_hook (pid); | |
4966 | } | |
4967 | ||
5b009018 PA |
4968 | /* Register a method that converts a siginfo object between the layout |
4969 | that ptrace returns, and the layout in the architecture of the | |
4970 | inferior. */ | |
4971 | void | |
4972 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4973 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4974 | gdb_byte *, |
4975 | int)) | |
4976 | { | |
4977 | /* Save the pointer. */ | |
4978 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4979 | } | |
4980 | ||
7b50312a PA |
4981 | /* Register a method to call prior to resuming a thread. */ |
4982 | ||
4983 | void | |
4984 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4985 | void (*prepare_to_resume) (struct lwp_info *)) | |
4986 | { | |
4987 | /* Save the pointer. */ | |
4988 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4989 | } | |
4990 | ||
f865ee35 JK |
4991 | /* See linux-nat.h. */ |
4992 | ||
4993 | int | |
4994 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4995 | { |
da559b09 | 4996 | int pid; |
9f0bdab8 | 4997 | |
dfd4cc63 | 4998 | pid = ptid_get_lwp (ptid); |
da559b09 | 4999 | if (pid == 0) |
dfd4cc63 | 5000 | pid = ptid_get_pid (ptid); |
f865ee35 | 5001 | |
da559b09 JK |
5002 | errno = 0; |
5003 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
5004 | if (errno != 0) | |
5005 | { | |
5006 | memset (siginfo, 0, sizeof (*siginfo)); | |
5007 | return 0; | |
5008 | } | |
f865ee35 | 5009 | return 1; |
9f0bdab8 DJ |
5010 | } |
5011 | ||
2c0b251b PA |
5012 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
5013 | extern initialize_file_ftype _initialize_linux_nat; | |
5014 | ||
d6b0e80f AC |
5015 | void |
5016 | _initialize_linux_nat (void) | |
5017 | { | |
ccce17b0 YQ |
5018 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
5019 | &debug_linux_nat, _("\ | |
b84876c2 PA |
5020 | Set debugging of GNU/Linux lwp module."), _("\ |
5021 | Show debugging of GNU/Linux lwp module."), _("\ | |
5022 | Enables printf debugging output."), | |
ccce17b0 YQ |
5023 | NULL, |
5024 | show_debug_linux_nat, | |
5025 | &setdebuglist, &showdebuglist); | |
b84876c2 | 5026 | |
b84876c2 | 5027 | /* Save this mask as the default. */ |
d6b0e80f AC |
5028 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
5029 | ||
7feb7d06 PA |
5030 | /* Install a SIGCHLD handler. */ |
5031 | sigchld_action.sa_handler = sigchld_handler; | |
5032 | sigemptyset (&sigchld_action.sa_mask); | |
5033 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
5034 | |
5035 | /* Make it the default. */ | |
7feb7d06 | 5036 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5037 | |
5038 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5039 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5040 | sigdelset (&suspend_mask, SIGCHLD); | |
5041 | ||
7feb7d06 | 5042 | sigemptyset (&blocked_mask); |
8009206a TT |
5043 | |
5044 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to | |
5045 | support read-only process state. */ | |
5046 | linux_ptrace_set_additional_flags (PTRACE_O_TRACESYSGOOD | |
5047 | | PTRACE_O_TRACEVFORKDONE | |
5048 | | PTRACE_O_TRACEVFORK | |
5049 | | PTRACE_O_TRACEFORK | |
5050 | | PTRACE_O_TRACEEXEC); | |
d6b0e80f AC |
5051 | } |
5052 | \f | |
5053 | ||
5054 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5055 | the GNU/Linux Threads library and therefore doesn't really belong | |
5056 | here. */ | |
5057 | ||
5058 | /* Read variable NAME in the target and return its value if found. | |
5059 | Otherwise return zero. It is assumed that the type of the variable | |
5060 | is `int'. */ | |
5061 | ||
5062 | static int | |
5063 | get_signo (const char *name) | |
5064 | { | |
3b7344d5 | 5065 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5066 | int signo; |
5067 | ||
5068 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5069 | if (ms.minsym == NULL) |
d6b0e80f AC |
5070 | return 0; |
5071 | ||
77e371c0 | 5072 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5073 | sizeof (signo)) != 0) |
5074 | return 0; | |
5075 | ||
5076 | return signo; | |
5077 | } | |
5078 | ||
5079 | /* Return the set of signals used by the threads library in *SET. */ | |
5080 | ||
5081 | void | |
5082 | lin_thread_get_thread_signals (sigset_t *set) | |
5083 | { | |
5084 | struct sigaction action; | |
5085 | int restart, cancel; | |
5086 | ||
b84876c2 | 5087 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5088 | sigemptyset (set); |
5089 | ||
5090 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5091 | cancel = get_signo ("__pthread_sig_cancel"); |
5092 | ||
5093 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5094 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5095 | not provide any way for the debugger to query the signal numbers - | |
5096 | fortunately they don't change! */ | |
5097 | ||
d6b0e80f | 5098 | if (restart == 0) |
17fbb0bd | 5099 | restart = __SIGRTMIN; |
d6b0e80f | 5100 | |
d6b0e80f | 5101 | if (cancel == 0) |
17fbb0bd | 5102 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5103 | |
5104 | sigaddset (set, restart); | |
5105 | sigaddset (set, cancel); | |
5106 | ||
5107 | /* The GNU/Linux Threads library makes terminating threads send a | |
5108 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5109 | those (to prevent them from terminating GDB itself, which is | |
5110 | likely to be their default action) and treat them the same way as | |
5111 | SIGCHLD. */ | |
5112 | ||
5113 | action.sa_handler = sigchld_handler; | |
5114 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5115 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5116 | sigaction (cancel, &action, NULL); |
5117 | ||
5118 | /* We block the "cancel" signal throughout this code ... */ | |
5119 | sigaddset (&blocked_mask, cancel); | |
5120 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5121 | ||
5122 | /* ... except during a sigsuspend. */ | |
5123 | sigdelset (&suspend_mask, cancel); | |
5124 | } |