Commit | Line | Data |
---|---|---|
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 | #include "gdb_assert.h" |
29 | #ifdef HAVE_TKILL_SYSCALL | |
30 | #include <unistd.h> | |
31 | #include <sys/syscall.h> | |
32 | #endif | |
3993f6b1 | 33 | #include <sys/ptrace.h> |
0274a8ce | 34 | #include "linux-nat.h" |
af96c192 | 35 | #include "linux-ptrace.h" |
13da1c97 | 36 | #include "linux-procfs.h" |
ac264b3b | 37 | #include "linux-fork.h" |
d6b0e80f AC |
38 | #include "gdbthread.h" |
39 | #include "gdbcmd.h" | |
40 | #include "regcache.h" | |
4f844a66 | 41 | #include "regset.h" |
dab06dbe | 42 | #include "inf-child.h" |
10d6c8cd DJ |
43 | #include "inf-ptrace.h" |
44 | #include "auxv.h" | |
1777feb0 | 45 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
46 | #include "elf-bfd.h" /* for elfcore_write_* */ |
47 | #include "gregset.h" /* for gregset */ | |
48 | #include "gdbcore.h" /* for get_exec_file */ | |
49 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 50 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 51 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
52 | #include "inf-loop.h" |
53 | #include "event-loop.h" | |
54 | #include "event-top.h" | |
07e059b5 VP |
55 | #include <pwd.h> |
56 | #include <sys/types.h> | |
2978b111 | 57 | #include <dirent.h> |
07e059b5 | 58 | #include "xml-support.h" |
191c4426 | 59 | #include "terminal.h" |
efcbbd14 | 60 | #include <sys/vfs.h> |
6c95b8df | 61 | #include "solib.h" |
d26e3629 | 62 | #include "linux-osdata.h" |
6432734d | 63 | #include "linux-tdep.h" |
7dcd53a0 | 64 | #include "symfile.h" |
5808517f YQ |
65 | #include "agent.h" |
66 | #include "tracepoint.h" | |
87b0bb13 | 67 | #include "exceptions.h" |
87b0bb13 | 68 | #include "buffer.h" |
6ecd4729 | 69 | #include "target-descriptions.h" |
614c279d | 70 | #include "filestuff.h" |
77e371c0 | 71 | #include "objfiles.h" |
efcbbd14 UW |
72 | |
73 | #ifndef SPUFS_MAGIC | |
74 | #define SPUFS_MAGIC 0x23c9b64e | |
75 | #endif | |
dba24537 | 76 | |
10568435 JK |
77 | #ifdef HAVE_PERSONALITY |
78 | # include <sys/personality.h> | |
79 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
80 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
81 | # endif | |
82 | #endif /* HAVE_PERSONALITY */ | |
83 | ||
1777feb0 | 84 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
85 | |
86 | Waiting for events in sync mode | |
87 | =============================== | |
88 | ||
89 | When waiting for an event in a specific thread, we just use waitpid, passing | |
90 | the specific pid, and not passing WNOHANG. | |
91 | ||
1777feb0 | 92 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 93 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 94 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
95 | miss an event. The solution is to use non-blocking waitpid, together with |
96 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 97 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
98 | flag to check for events in cloned processes. If nothing is found, we use |
99 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
100 | happened to a child process -- and SIGCHLD will be delivered both for events | |
101 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
102 | an event, we get back to calling nonblocking waitpid with and without |
103 | __WCLONED. | |
8a77dff3 VP |
104 | |
105 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 106 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
107 | blocked, the signal becomes pending and sigsuspend immediately |
108 | notices it and returns. | |
109 | ||
110 | Waiting for events in async mode | |
111 | ================================ | |
112 | ||
7feb7d06 PA |
113 | In async mode, GDB should always be ready to handle both user input |
114 | and target events, so neither blocking waitpid nor sigsuspend are | |
115 | viable options. Instead, we should asynchronously notify the GDB main | |
116 | event loop whenever there's an unprocessed event from the target. We | |
117 | detect asynchronous target events by handling SIGCHLD signals. To | |
118 | notify the event loop about target events, the self-pipe trick is used | |
119 | --- a pipe is registered as waitable event source in the event loop, | |
120 | the event loop select/poll's on the read end of this pipe (as well on | |
121 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
122 | byte to this pipe. This is more portable than relying on | |
123 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
124 | emulates them with select/poll+sigprocmask, and that is racy | |
125 | (a.k.a. plain broken). | |
126 | ||
127 | Obviously, if we fail to notify the event loop if there's a target | |
128 | event, it's bad. OTOH, if we notify the event loop when there's no | |
129 | event from the target, linux_nat_wait will detect that there's no real | |
130 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
131 | This is mostly harmless, but it will waste time and is better avoided. | |
132 | ||
133 | The main design point is that every time GDB is outside linux-nat.c, | |
134 | we have a SIGCHLD handler installed that is called when something | |
135 | happens to the target and notifies the GDB event loop. Whenever GDB | |
136 | core decides to handle the event, and calls into linux-nat.c, we | |
137 | process things as in sync mode, except that the we never block in | |
138 | sigsuspend. | |
139 | ||
140 | While processing an event, we may end up momentarily blocked in | |
141 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
142 | return quickly. E.g., in all-stop mode, before reporting to the core | |
143 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
144 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
145 | Note that this is different from blocking indefinitely waiting for the | |
146 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
147 | |
148 | Use of signals | |
149 | ============== | |
150 | ||
151 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
152 | signal is not entirely significant; we just need for a signal to be delivered, | |
153 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
154 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
155 | be queued once; we do not keep track of other sources of SIGSTOP. | |
156 | ||
157 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
158 | use them, because they have special behavior when the signal is generated - | |
159 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
160 | kills the entire thread group. | |
161 | ||
162 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
163 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
164 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
165 | ||
166 | We could use a real-time signal instead. This would solve those problems; we | |
167 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
168 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
169 | generates it, and there are races with trying to find a signal that is not | |
170 | blocked. */ | |
a0ef4274 | 171 | |
dba24537 AC |
172 | #ifndef O_LARGEFILE |
173 | #define O_LARGEFILE 0 | |
174 | #endif | |
0274a8ce | 175 | |
10d6c8cd DJ |
176 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
177 | the use of the multi-threaded target. */ | |
178 | static struct target_ops *linux_ops; | |
f973ed9c | 179 | static struct target_ops linux_ops_saved; |
10d6c8cd | 180 | |
9f0bdab8 | 181 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
182 | static void (*linux_nat_new_thread) (struct lwp_info *); |
183 | ||
26cb8b7c PA |
184 | /* The method to call, if any, when a new fork is attached. */ |
185 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
186 | ||
187 | /* The method to call, if any, when a process is no longer | |
188 | attached. */ | |
189 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
190 | ||
7b50312a PA |
191 | /* Hook to call prior to resuming a thread. */ |
192 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 193 | |
5b009018 PA |
194 | /* The method to call, if any, when the siginfo object needs to be |
195 | converted between the layout returned by ptrace, and the layout in | |
196 | the architecture of the inferior. */ | |
a5362b9a | 197 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
198 | gdb_byte *, |
199 | int); | |
200 | ||
ac264b3b MS |
201 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
202 | Called by our to_xfer_partial. */ | |
4ac248ca | 203 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 204 | |
6a3cb8e8 PA |
205 | /* The saved to_close method, inherited from inf-ptrace.c. |
206 | Called by our to_close. */ | |
207 | static void (*super_close) (struct target_ops *); | |
208 | ||
ccce17b0 | 209 | static unsigned int debug_linux_nat; |
920d2a44 AC |
210 | static void |
211 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
212 | struct cmd_list_element *c, const char *value) | |
213 | { | |
214 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
215 | value); | |
216 | } | |
d6b0e80f | 217 | |
ae087d01 DJ |
218 | struct simple_pid_list |
219 | { | |
220 | int pid; | |
3d799a95 | 221 | int status; |
ae087d01 DJ |
222 | struct simple_pid_list *next; |
223 | }; | |
224 | struct simple_pid_list *stopped_pids; | |
225 | ||
3dd5b83d PA |
226 | /* Async mode support. */ |
227 | ||
b84876c2 PA |
228 | /* The read/write ends of the pipe registered as waitable file in the |
229 | event loop. */ | |
230 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
231 | ||
7feb7d06 | 232 | /* Flush the event pipe. */ |
b84876c2 | 233 | |
7feb7d06 PA |
234 | static void |
235 | async_file_flush (void) | |
b84876c2 | 236 | { |
7feb7d06 PA |
237 | int ret; |
238 | char buf; | |
b84876c2 | 239 | |
7feb7d06 | 240 | do |
b84876c2 | 241 | { |
7feb7d06 | 242 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 243 | } |
7feb7d06 | 244 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
245 | } |
246 | ||
7feb7d06 PA |
247 | /* Put something (anything, doesn't matter what, or how much) in event |
248 | pipe, so that the select/poll in the event-loop realizes we have | |
249 | something to process. */ | |
252fbfc8 | 250 | |
b84876c2 | 251 | static void |
7feb7d06 | 252 | async_file_mark (void) |
b84876c2 | 253 | { |
7feb7d06 | 254 | int ret; |
b84876c2 | 255 | |
7feb7d06 PA |
256 | /* It doesn't really matter what the pipe contains, as long we end |
257 | up with something in it. Might as well flush the previous | |
258 | left-overs. */ | |
259 | async_file_flush (); | |
b84876c2 | 260 | |
7feb7d06 | 261 | do |
b84876c2 | 262 | { |
7feb7d06 | 263 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 264 | } |
7feb7d06 | 265 | while (ret == -1 && errno == EINTR); |
b84876c2 | 266 | |
7feb7d06 PA |
267 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
268 | be awakened anyway. */ | |
b84876c2 PA |
269 | } |
270 | ||
7feb7d06 PA |
271 | static int kill_lwp (int lwpid, int signo); |
272 | ||
273 | static int stop_callback (struct lwp_info *lp, void *data); | |
274 | ||
275 | static void block_child_signals (sigset_t *prev_mask); | |
276 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
277 | |
278 | struct lwp_info; | |
279 | static struct lwp_info *add_lwp (ptid_t ptid); | |
280 | static void purge_lwp_list (int pid); | |
4403d8e9 | 281 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
282 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
283 | ||
ae087d01 DJ |
284 | \f |
285 | /* Trivial list manipulation functions to keep track of a list of | |
286 | new stopped processes. */ | |
287 | static void | |
3d799a95 | 288 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
289 | { |
290 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 291 | |
ae087d01 | 292 | new_pid->pid = pid; |
3d799a95 | 293 | new_pid->status = status; |
ae087d01 DJ |
294 | new_pid->next = *listp; |
295 | *listp = new_pid; | |
296 | } | |
297 | ||
84636d28 PA |
298 | static int |
299 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
300 | { | |
301 | struct simple_pid_list *p; | |
302 | ||
303 | for (p = list; p != NULL; p = p->next) | |
304 | if (p->pid == pid) | |
305 | return 1; | |
306 | return 0; | |
307 | } | |
308 | ||
ae087d01 | 309 | static int |
46a96992 | 310 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
311 | { |
312 | struct simple_pid_list **p; | |
313 | ||
314 | for (p = listp; *p != NULL; p = &(*p)->next) | |
315 | if ((*p)->pid == pid) | |
316 | { | |
317 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 318 | |
46a96992 | 319 | *statusp = (*p)->status; |
ae087d01 DJ |
320 | xfree (*p); |
321 | *p = next; | |
322 | return 1; | |
323 | } | |
324 | return 0; | |
325 | } | |
326 | ||
96d7229d LM |
327 | /* Initialize ptrace warnings and check for supported ptrace |
328 | features given PID. */ | |
3993f6b1 DJ |
329 | |
330 | static void | |
96d7229d | 331 | linux_init_ptrace (pid_t pid) |
3993f6b1 | 332 | { |
96d7229d LM |
333 | linux_enable_event_reporting (pid); |
334 | linux_ptrace_init_warnings (); | |
4de4c07c DJ |
335 | } |
336 | ||
6d8fd2b7 | 337 | static void |
f045800c | 338 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 339 | { |
96d7229d | 340 | linux_init_ptrace (pid); |
4de4c07c DJ |
341 | } |
342 | ||
10d6c8cd | 343 | static void |
2e97a79e | 344 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 345 | { |
96d7229d | 346 | linux_init_ptrace (ptid_get_pid (ptid)); |
4de4c07c DJ |
347 | } |
348 | ||
4403d8e9 JK |
349 | /* Return the number of known LWPs in the tgid given by PID. */ |
350 | ||
351 | static int | |
352 | num_lwps (int pid) | |
353 | { | |
354 | int count = 0; | |
355 | struct lwp_info *lp; | |
356 | ||
357 | for (lp = lwp_list; lp; lp = lp->next) | |
358 | if (ptid_get_pid (lp->ptid) == pid) | |
359 | count++; | |
360 | ||
361 | return count; | |
362 | } | |
363 | ||
364 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
365 | ||
366 | static void | |
367 | delete_lwp_cleanup (void *lp_voidp) | |
368 | { | |
369 | struct lwp_info *lp = lp_voidp; | |
370 | ||
371 | delete_lwp (lp->ptid); | |
372 | } | |
373 | ||
6d8fd2b7 | 374 | static int |
07107ca6 LM |
375 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
376 | int detach_fork) | |
3993f6b1 | 377 | { |
9016a515 | 378 | int has_vforked; |
4de4c07c DJ |
379 | int parent_pid, child_pid; |
380 | ||
e58b0e63 PA |
381 | has_vforked = (inferior_thread ()->pending_follow.kind |
382 | == TARGET_WAITKIND_VFORKED); | |
383 | parent_pid = ptid_get_lwp (inferior_ptid); | |
d3587048 | 384 | if (parent_pid == 0) |
e58b0e63 | 385 | parent_pid = ptid_get_pid (inferior_ptid); |
dfd4cc63 LM |
386 | child_pid |
387 | = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid); | |
4de4c07c | 388 | |
6c95b8df PA |
389 | if (has_vforked |
390 | && !non_stop /* Non-stop always resumes both branches. */ | |
391 | && (!target_is_async_p () || sync_execution) | |
392 | && !(follow_child || detach_fork || sched_multi)) | |
393 | { | |
394 | /* The parent stays blocked inside the vfork syscall until the | |
395 | child execs or exits. If we don't let the child run, then | |
396 | the parent stays blocked. If we're telling the parent to run | |
397 | in the foreground, the user will not be able to ctrl-c to get | |
398 | back the terminal, effectively hanging the debug session. */ | |
ac74f770 MS |
399 | fprintf_filtered (gdb_stderr, _("\ |
400 | Can not resume the parent process over vfork in the foreground while\n\ | |
401 | holding the child stopped. Try \"set detach-on-fork\" or \ | |
402 | \"set schedule-multiple\".\n")); | |
403 | /* FIXME output string > 80 columns. */ | |
6c95b8df PA |
404 | return 1; |
405 | } | |
406 | ||
4de4c07c DJ |
407 | if (! follow_child) |
408 | { | |
6c95b8df | 409 | struct lwp_info *child_lp = NULL; |
4de4c07c | 410 | |
1777feb0 | 411 | /* We're already attached to the parent, by default. */ |
4de4c07c | 412 | |
ac264b3b MS |
413 | /* Detach new forked process? */ |
414 | if (detach_fork) | |
f75c00e4 | 415 | { |
4403d8e9 | 416 | struct cleanup *old_chain; |
9caaaa83 | 417 | int status = W_STOPCODE (0); |
4403d8e9 | 418 | |
6c95b8df PA |
419 | /* Before detaching from the child, remove all breakpoints |
420 | from it. If we forked, then this has already been taken | |
421 | care of by infrun.c. If we vforked however, any | |
422 | breakpoint inserted in the parent is visible in the | |
423 | child, even those added while stopped in a vfork | |
424 | catchpoint. This will remove the breakpoints from the | |
425 | parent also, but they'll be reinserted below. */ | |
426 | if (has_vforked) | |
427 | { | |
428 | /* keep breakpoints list in sync. */ | |
dfd4cc63 | 429 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
6c95b8df PA |
430 | } |
431 | ||
e85a822c | 432 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
433 | { |
434 | target_terminal_ours (); | |
435 | fprintf_filtered (gdb_stdlog, | |
3e43a32a MS |
436 | "Detaching after fork from " |
437 | "child process %d.\n", | |
ac264b3b MS |
438 | child_pid); |
439 | } | |
4de4c07c | 440 | |
4403d8e9 JK |
441 | old_chain = save_inferior_ptid (); |
442 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
443 | ||
444 | child_lp = add_lwp (inferior_ptid); | |
445 | child_lp->stopped = 1; | |
446 | child_lp->last_resume_kind = resume_stop; | |
447 | make_cleanup (delete_lwp_cleanup, child_lp); | |
448 | ||
4403d8e9 JK |
449 | if (linux_nat_prepare_to_resume != NULL) |
450 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
451 | |
452 | /* When debugging an inferior in an architecture that supports | |
453 | hardware single stepping on a kernel without commit | |
454 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
455 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
456 | set if the parent process had them set. | |
457 | To work around this, single step the child process | |
458 | once before detaching to clear the flags. */ | |
459 | ||
460 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
461 | (child_lp->ptid))) | |
462 | { | |
c077881a HZ |
463 | linux_disable_event_reporting (child_pid); |
464 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
465 | perror_with_name (_("Couldn't do single step")); | |
466 | if (my_waitpid (child_pid, &status, 0) < 0) | |
467 | perror_with_name (_("Couldn't wait vfork process")); | |
468 | } | |
469 | ||
470 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
471 | { |
472 | int signo; | |
473 | ||
474 | signo = WSTOPSIG (status); | |
475 | if (signo != 0 | |
476 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
477 | signo = 0; | |
478 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
479 | } | |
4403d8e9 JK |
480 | |
481 | do_cleanups (old_chain); | |
ac264b3b MS |
482 | } |
483 | else | |
484 | { | |
77435e4c | 485 | struct inferior *parent_inf, *child_inf; |
2277426b | 486 | struct cleanup *old_chain; |
7f9f62ba PA |
487 | |
488 | /* Add process to GDB's tables. */ | |
77435e4c PA |
489 | child_inf = add_inferior (child_pid); |
490 | ||
e58b0e63 | 491 | parent_inf = current_inferior (); |
77435e4c | 492 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 493 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
494 | child_inf->gdbarch = parent_inf->gdbarch; |
495 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7f9f62ba | 496 | |
2277426b | 497 | old_chain = save_inferior_ptid (); |
6c95b8df | 498 | save_current_program_space (); |
2277426b PA |
499 | |
500 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
501 | add_thread (inferior_ptid); | |
6c95b8df PA |
502 | child_lp = add_lwp (inferior_ptid); |
503 | child_lp->stopped = 1; | |
25289eb2 | 504 | child_lp->last_resume_kind = resume_stop; |
7dcd53a0 | 505 | child_inf->symfile_flags = SYMFILE_NO_READ; |
2277426b | 506 | |
6c95b8df PA |
507 | /* If this is a vfork child, then the address-space is |
508 | shared with the parent. */ | |
509 | if (has_vforked) | |
510 | { | |
511 | child_inf->pspace = parent_inf->pspace; | |
512 | child_inf->aspace = parent_inf->aspace; | |
513 | ||
514 | /* The parent will be frozen until the child is done | |
515 | with the shared region. Keep track of the | |
516 | parent. */ | |
517 | child_inf->vfork_parent = parent_inf; | |
518 | child_inf->pending_detach = 0; | |
519 | parent_inf->vfork_child = child_inf; | |
520 | parent_inf->pending_detach = 0; | |
521 | } | |
522 | else | |
523 | { | |
524 | child_inf->aspace = new_address_space (); | |
525 | child_inf->pspace = add_program_space (child_inf->aspace); | |
526 | child_inf->removable = 1; | |
527 | set_current_program_space (child_inf->pspace); | |
528 | clone_program_space (child_inf->pspace, parent_inf->pspace); | |
529 | ||
530 | /* Let the shared library layer (solib-svr4) learn about | |
531 | this new process, relocate the cloned exec, pull in | |
532 | shared libraries, and install the solib event | |
533 | breakpoint. If a "cloned-VM" event was propagated | |
534 | better throughout the core, this wouldn't be | |
535 | required. */ | |
268a4a75 | 536 | solib_create_inferior_hook (0); |
6c95b8df PA |
537 | } |
538 | ||
539 | /* Let the thread_db layer learn about this new process. */ | |
2277426b PA |
540 | check_for_thread_db (); |
541 | ||
542 | do_cleanups (old_chain); | |
ac264b3b | 543 | } |
9016a515 DJ |
544 | |
545 | if (has_vforked) | |
546 | { | |
3ced3da4 | 547 | struct lwp_info *parent_lp; |
6c95b8df PA |
548 | struct inferior *parent_inf; |
549 | ||
550 | parent_inf = current_inferior (); | |
551 | ||
552 | /* If we detached from the child, then we have to be careful | |
553 | to not insert breakpoints in the parent until the child | |
554 | is done with the shared memory region. However, if we're | |
555 | staying attached to the child, then we can and should | |
556 | insert breakpoints, so that we can debug it. A | |
557 | subsequent child exec or exit is enough to know when does | |
558 | the child stops using the parent's address space. */ | |
559 | parent_inf->waiting_for_vfork_done = detach_fork; | |
56710373 | 560 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
6c95b8df | 561 | |
3ced3da4 | 562 | parent_lp = find_lwp_pid (pid_to_ptid (parent_pid)); |
96d7229d | 563 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 564 | |
96d7229d | 565 | if (linux_supports_tracevforkdone ()) |
9016a515 | 566 | { |
6c95b8df PA |
567 | if (debug_linux_nat) |
568 | fprintf_unfiltered (gdb_stdlog, | |
569 | "LCFF: waiting for VFORK_DONE on %d\n", | |
570 | parent_pid); | |
3ced3da4 | 571 | parent_lp->stopped = 1; |
9016a515 | 572 | |
6c95b8df PA |
573 | /* We'll handle the VFORK_DONE event like any other |
574 | event, in target_wait. */ | |
9016a515 DJ |
575 | } |
576 | else | |
577 | { | |
578 | /* We can't insert breakpoints until the child has | |
579 | finished with the shared memory region. We need to | |
580 | wait until that happens. Ideal would be to just | |
581 | call: | |
582 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
583 | - waitpid (parent_pid, &status, __WALL); | |
584 | However, most architectures can't handle a syscall | |
585 | being traced on the way out if it wasn't traced on | |
586 | the way in. | |
587 | ||
588 | We might also think to loop, continuing the child | |
589 | until it exits or gets a SIGTRAP. One problem is | |
590 | that the child might call ptrace with PTRACE_TRACEME. | |
591 | ||
592 | There's no simple and reliable way to figure out when | |
593 | the vforked child will be done with its copy of the | |
594 | shared memory. We could step it out of the syscall, | |
595 | two instructions, let it go, and then single-step the | |
596 | parent once. When we have hardware single-step, this | |
597 | would work; with software single-step it could still | |
598 | be made to work but we'd have to be able to insert | |
599 | single-step breakpoints in the child, and we'd have | |
600 | to insert -just- the single-step breakpoint in the | |
601 | parent. Very awkward. | |
602 | ||
603 | In the end, the best we can do is to make sure it | |
604 | runs for a little while. Hopefully it will be out of | |
605 | range of any breakpoints we reinsert. Usually this | |
606 | is only the single-step breakpoint at vfork's return | |
607 | point. */ | |
608 | ||
6c95b8df PA |
609 | if (debug_linux_nat) |
610 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
611 | "LCFF: no VFORK_DONE " |
612 | "support, sleeping a bit\n"); | |
6c95b8df | 613 | |
9016a515 | 614 | usleep (10000); |
9016a515 | 615 | |
6c95b8df PA |
616 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
617 | and leave it pending. The next linux_nat_resume call | |
618 | will notice a pending event, and bypasses actually | |
619 | resuming the inferior. */ | |
3ced3da4 PA |
620 | parent_lp->status = 0; |
621 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
622 | parent_lp->stopped = 1; | |
6c95b8df PA |
623 | |
624 | /* If we're in async mode, need to tell the event loop | |
625 | there's something here to process. */ | |
626 | if (target_can_async_p ()) | |
627 | async_file_mark (); | |
628 | } | |
9016a515 | 629 | } |
4de4c07c | 630 | } |
3993f6b1 | 631 | else |
4de4c07c | 632 | { |
77435e4c | 633 | struct inferior *parent_inf, *child_inf; |
3ced3da4 | 634 | struct lwp_info *child_lp; |
6c95b8df | 635 | struct program_space *parent_pspace; |
4de4c07c | 636 | |
e85a822c | 637 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
638 | { |
639 | target_terminal_ours (); | |
6c95b8df | 640 | if (has_vforked) |
3e43a32a MS |
641 | fprintf_filtered (gdb_stdlog, |
642 | _("Attaching after process %d " | |
643 | "vfork to child process %d.\n"), | |
6c95b8df PA |
644 | parent_pid, child_pid); |
645 | else | |
3e43a32a MS |
646 | fprintf_filtered (gdb_stdlog, |
647 | _("Attaching after process %d " | |
648 | "fork to child process %d.\n"), | |
6c95b8df | 649 | parent_pid, child_pid); |
f75c00e4 | 650 | } |
4de4c07c | 651 | |
7a7d3353 PA |
652 | /* Add the new inferior first, so that the target_detach below |
653 | doesn't unpush the target. */ | |
654 | ||
77435e4c PA |
655 | child_inf = add_inferior (child_pid); |
656 | ||
e58b0e63 | 657 | parent_inf = current_inferior (); |
77435e4c | 658 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 659 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
660 | child_inf->gdbarch = parent_inf->gdbarch; |
661 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7a7d3353 | 662 | |
6c95b8df | 663 | parent_pspace = parent_inf->pspace; |
9016a515 | 664 | |
6c95b8df PA |
665 | /* If we're vforking, we want to hold on to the parent until the |
666 | child exits or execs. At child exec or exit time we can | |
667 | remove the old breakpoints from the parent and detach or | |
668 | resume debugging it. Otherwise, detach the parent now; we'll | |
669 | want to reuse it's program/address spaces, but we can't set | |
670 | them to the child before removing breakpoints from the | |
671 | parent, otherwise, the breakpoints module could decide to | |
672 | remove breakpoints from the wrong process (since they'd be | |
673 | assigned to the same address space). */ | |
9016a515 DJ |
674 | |
675 | if (has_vforked) | |
7f9f62ba | 676 | { |
6c95b8df PA |
677 | gdb_assert (child_inf->vfork_parent == NULL); |
678 | gdb_assert (parent_inf->vfork_child == NULL); | |
679 | child_inf->vfork_parent = parent_inf; | |
680 | child_inf->pending_detach = 0; | |
681 | parent_inf->vfork_child = child_inf; | |
682 | parent_inf->pending_detach = detach_fork; | |
683 | parent_inf->waiting_for_vfork_done = 0; | |
ac264b3b | 684 | } |
2277426b | 685 | else if (detach_fork) |
b84876c2 | 686 | target_detach (NULL, 0); |
4de4c07c | 687 | |
6c95b8df PA |
688 | /* Note that the detach above makes PARENT_INF dangling. */ |
689 | ||
690 | /* Add the child thread to the appropriate lists, and switch to | |
691 | this new thread, before cloning the program space, and | |
692 | informing the solib layer about this new process. */ | |
693 | ||
9f0bdab8 | 694 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
2277426b | 695 | add_thread (inferior_ptid); |
3ced3da4 PA |
696 | child_lp = add_lwp (inferior_ptid); |
697 | child_lp->stopped = 1; | |
25289eb2 | 698 | child_lp->last_resume_kind = resume_stop; |
6c95b8df PA |
699 | |
700 | /* If this is a vfork child, then the address-space is shared | |
701 | with the parent. If we detached from the parent, then we can | |
702 | reuse the parent's program/address spaces. */ | |
703 | if (has_vforked || detach_fork) | |
704 | { | |
705 | child_inf->pspace = parent_pspace; | |
706 | child_inf->aspace = child_inf->pspace->aspace; | |
707 | } | |
708 | else | |
709 | { | |
710 | child_inf->aspace = new_address_space (); | |
711 | child_inf->pspace = add_program_space (child_inf->aspace); | |
712 | child_inf->removable = 1; | |
7dcd53a0 | 713 | child_inf->symfile_flags = SYMFILE_NO_READ; |
6c95b8df PA |
714 | set_current_program_space (child_inf->pspace); |
715 | clone_program_space (child_inf->pspace, parent_pspace); | |
716 | ||
717 | /* Let the shared library layer (solib-svr4) learn about | |
718 | this new process, relocate the cloned exec, pull in | |
719 | shared libraries, and install the solib event breakpoint. | |
720 | If a "cloned-VM" event was propagated better throughout | |
721 | the core, this wouldn't be required. */ | |
268a4a75 | 722 | solib_create_inferior_hook (0); |
6c95b8df | 723 | } |
ac264b3b | 724 | |
6c95b8df | 725 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 726 | check_for_thread_db (); |
4de4c07c DJ |
727 | } |
728 | ||
729 | return 0; | |
730 | } | |
731 | ||
4de4c07c | 732 | \f |
77b06cd7 | 733 | static int |
a863b201 | 734 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 735 | { |
96d7229d | 736 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
737 | } |
738 | ||
eb73ad13 | 739 | static int |
973fc227 | 740 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
741 | { |
742 | return 0; | |
743 | } | |
744 | ||
77b06cd7 | 745 | static int |
3ecc7da0 | 746 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 747 | { |
96d7229d | 748 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
749 | } |
750 | ||
eb73ad13 | 751 | static int |
e98cf0cd | 752 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
753 | { |
754 | return 0; | |
755 | } | |
756 | ||
77b06cd7 | 757 | static int |
ba025e51 | 758 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 759 | { |
96d7229d | 760 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
761 | } |
762 | ||
eb73ad13 | 763 | static int |
758e29d2 | 764 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
765 | { |
766 | return 0; | |
767 | } | |
768 | ||
a96d9b2e | 769 | static int |
ff214e67 TT |
770 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
771 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
772 | int table_size, int *table) |
773 | { | |
96d7229d | 774 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
775 | return 1; |
776 | ||
a96d9b2e SDJ |
777 | /* On GNU/Linux, we ignore the arguments. It means that we only |
778 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 779 | |
a96d9b2e SDJ |
780 | Also, we do not use the `table' information because we do not |
781 | filter system calls here. We let GDB do the logic for us. */ | |
782 | return 0; | |
783 | } | |
784 | ||
d6b0e80f AC |
785 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
786 | are processes sharing the same VM space. A multi-threaded process | |
787 | is basically a group of such processes. However, such a grouping | |
788 | is almost entirely a user-space issue; the kernel doesn't enforce | |
789 | such a grouping at all (this might change in the future). In | |
790 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
791 | Threads library) to provide such a grouping. | |
792 | ||
793 | It is perfectly well possible to write a multi-threaded application | |
794 | without the assistance of a threads library, by using the clone | |
795 | system call directly. This module should be able to give some | |
796 | rudimentary support for debugging such applications if developers | |
797 | specify the CLONE_PTRACE flag in the clone system call, and are | |
798 | using the Linux kernel 2.4 or above. | |
799 | ||
800 | Note that there are some peculiarities in GNU/Linux that affect | |
801 | this code: | |
802 | ||
803 | - In general one should specify the __WCLONE flag to waitpid in | |
804 | order to make it report events for any of the cloned processes | |
805 | (and leave it out for the initial process). However, if a cloned | |
806 | process has exited the exit status is only reported if the | |
807 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
808 | we cannot use it since GDB must work on older systems too. | |
809 | ||
810 | - When a traced, cloned process exits and is waited for by the | |
811 | debugger, the kernel reassigns it to the original parent and | |
812 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
813 | library doesn't notice this, which leads to the "zombie problem": | |
814 | When debugged a multi-threaded process that spawns a lot of | |
815 | threads will run out of processes, even if the threads exit, | |
816 | because the "zombies" stay around. */ | |
817 | ||
818 | /* List of known LWPs. */ | |
9f0bdab8 | 819 | struct lwp_info *lwp_list; |
d6b0e80f AC |
820 | \f |
821 | ||
d6b0e80f AC |
822 | /* Original signal mask. */ |
823 | static sigset_t normal_mask; | |
824 | ||
825 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
826 | _initialize_linux_nat. */ | |
827 | static sigset_t suspend_mask; | |
828 | ||
7feb7d06 PA |
829 | /* Signals to block to make that sigsuspend work. */ |
830 | static sigset_t blocked_mask; | |
831 | ||
832 | /* SIGCHLD action. */ | |
833 | struct sigaction sigchld_action; | |
b84876c2 | 834 | |
7feb7d06 PA |
835 | /* Block child signals (SIGCHLD and linux threads signals), and store |
836 | the previous mask in PREV_MASK. */ | |
84e46146 | 837 | |
7feb7d06 PA |
838 | static void |
839 | block_child_signals (sigset_t *prev_mask) | |
840 | { | |
841 | /* Make sure SIGCHLD is blocked. */ | |
842 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
843 | sigaddset (&blocked_mask, SIGCHLD); | |
844 | ||
845 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
846 | } | |
847 | ||
848 | /* Restore child signals mask, previously returned by | |
849 | block_child_signals. */ | |
850 | ||
851 | static void | |
852 | restore_child_signals_mask (sigset_t *prev_mask) | |
853 | { | |
854 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
855 | } | |
2455069d UW |
856 | |
857 | /* Mask of signals to pass directly to the inferior. */ | |
858 | static sigset_t pass_mask; | |
859 | ||
860 | /* Update signals to pass to the inferior. */ | |
861 | static void | |
94bedb42 TT |
862 | linux_nat_pass_signals (struct target_ops *self, |
863 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
864 | { |
865 | int signo; | |
866 | ||
867 | sigemptyset (&pass_mask); | |
868 | ||
869 | for (signo = 1; signo < NSIG; signo++) | |
870 | { | |
2ea28649 | 871 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
872 | if (target_signo < numsigs && pass_signals[target_signo]) |
873 | sigaddset (&pass_mask, signo); | |
874 | } | |
875 | } | |
876 | ||
d6b0e80f AC |
877 | \f |
878 | ||
879 | /* Prototypes for local functions. */ | |
880 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 881 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 882 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
710151dd | 883 | |
d6b0e80f | 884 | \f |
d6b0e80f | 885 | |
7b50312a PA |
886 | /* Destroy and free LP. */ |
887 | ||
888 | static void | |
889 | lwp_free (struct lwp_info *lp) | |
890 | { | |
891 | xfree (lp->arch_private); | |
892 | xfree (lp); | |
893 | } | |
894 | ||
d90e17a7 PA |
895 | /* Remove all LWPs belong to PID from the lwp list. */ |
896 | ||
897 | static void | |
898 | purge_lwp_list (int pid) | |
899 | { | |
900 | struct lwp_info *lp, *lpprev, *lpnext; | |
901 | ||
902 | lpprev = NULL; | |
903 | ||
904 | for (lp = lwp_list; lp; lp = lpnext) | |
905 | { | |
906 | lpnext = lp->next; | |
907 | ||
908 | if (ptid_get_pid (lp->ptid) == pid) | |
909 | { | |
910 | if (lp == lwp_list) | |
911 | lwp_list = lp->next; | |
912 | else | |
913 | lpprev->next = lp->next; | |
914 | ||
7b50312a | 915 | lwp_free (lp); |
d90e17a7 PA |
916 | } |
917 | else | |
918 | lpprev = lp; | |
919 | } | |
920 | } | |
921 | ||
26cb8b7c PA |
922 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
923 | in the process. Return a pointer to the structure describing the | |
924 | new LWP. | |
925 | ||
926 | This differs from add_lwp in that we don't let the arch specific | |
927 | bits know about this new thread. Current clients of this callback | |
928 | take the opportunity to install watchpoints in the new thread, and | |
929 | we shouldn't do that for the first thread. If we're spawning a | |
930 | child ("run"), the thread executes the shell wrapper first, and we | |
931 | shouldn't touch it until it execs the program we want to debug. | |
932 | For "attach", it'd be okay to call the callback, but it's not | |
933 | necessary, because watchpoints can't yet have been inserted into | |
934 | the inferior. */ | |
d6b0e80f AC |
935 | |
936 | static struct lwp_info * | |
26cb8b7c | 937 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
938 | { |
939 | struct lwp_info *lp; | |
940 | ||
dfd4cc63 | 941 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
942 | |
943 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
944 | ||
945 | memset (lp, 0, sizeof (struct lwp_info)); | |
946 | ||
25289eb2 | 947 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
948 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
949 | ||
950 | lp->ptid = ptid; | |
dc146f7c | 951 | lp->core = -1; |
d6b0e80f AC |
952 | |
953 | lp->next = lwp_list; | |
954 | lwp_list = lp; | |
d6b0e80f | 955 | |
26cb8b7c PA |
956 | return lp; |
957 | } | |
958 | ||
959 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
960 | structure describing the new LWP. The LWP should already be | |
961 | stopped. */ | |
962 | ||
963 | static struct lwp_info * | |
964 | add_lwp (ptid_t ptid) | |
965 | { | |
966 | struct lwp_info *lp; | |
967 | ||
968 | lp = add_initial_lwp (ptid); | |
969 | ||
6e012a6c PA |
970 | /* Let the arch specific bits know about this new thread. Current |
971 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
972 | watchpoints in the new thread. We don't do this for the first |
973 | thread though. See add_initial_lwp. */ | |
974 | if (linux_nat_new_thread != NULL) | |
7b50312a | 975 | linux_nat_new_thread (lp); |
9f0bdab8 | 976 | |
d6b0e80f AC |
977 | return lp; |
978 | } | |
979 | ||
980 | /* Remove the LWP specified by PID from the list. */ | |
981 | ||
982 | static void | |
983 | delete_lwp (ptid_t ptid) | |
984 | { | |
985 | struct lwp_info *lp, *lpprev; | |
986 | ||
987 | lpprev = NULL; | |
988 | ||
989 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
990 | if (ptid_equal (lp->ptid, ptid)) | |
991 | break; | |
992 | ||
993 | if (!lp) | |
994 | return; | |
995 | ||
d6b0e80f AC |
996 | if (lpprev) |
997 | lpprev->next = lp->next; | |
998 | else | |
999 | lwp_list = lp->next; | |
1000 | ||
7b50312a | 1001 | lwp_free (lp); |
d6b0e80f AC |
1002 | } |
1003 | ||
1004 | /* Return a pointer to the structure describing the LWP corresponding | |
1005 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1006 | ||
1007 | static struct lwp_info * | |
1008 | find_lwp_pid (ptid_t ptid) | |
1009 | { | |
1010 | struct lwp_info *lp; | |
1011 | int lwp; | |
1012 | ||
dfd4cc63 LM |
1013 | if (ptid_lwp_p (ptid)) |
1014 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 1015 | else |
dfd4cc63 | 1016 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
1017 | |
1018 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 1019 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
1020 | return lp; |
1021 | ||
1022 | return NULL; | |
1023 | } | |
1024 | ||
1025 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1026 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1027 | pointer to the structure describing that LWP immediately. | |
1028 | Otherwise return NULL. */ | |
1029 | ||
1030 | struct lwp_info * | |
d90e17a7 PA |
1031 | iterate_over_lwps (ptid_t filter, |
1032 | int (*callback) (struct lwp_info *, void *), | |
1033 | void *data) | |
d6b0e80f AC |
1034 | { |
1035 | struct lwp_info *lp, *lpnext; | |
1036 | ||
1037 | for (lp = lwp_list; lp; lp = lpnext) | |
1038 | { | |
1039 | lpnext = lp->next; | |
d90e17a7 PA |
1040 | |
1041 | if (ptid_match (lp->ptid, filter)) | |
1042 | { | |
1043 | if ((*callback) (lp, data)) | |
1044 | return lp; | |
1045 | } | |
d6b0e80f AC |
1046 | } |
1047 | ||
1048 | return NULL; | |
1049 | } | |
1050 | ||
2277426b PA |
1051 | /* Update our internal state when changing from one checkpoint to |
1052 | another indicated by NEW_PTID. We can only switch single-threaded | |
1053 | applications, so we only create one new LWP, and the previous list | |
1054 | is discarded. */ | |
f973ed9c DJ |
1055 | |
1056 | void | |
1057 | linux_nat_switch_fork (ptid_t new_ptid) | |
1058 | { | |
1059 | struct lwp_info *lp; | |
1060 | ||
dfd4cc63 | 1061 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 1062 | |
f973ed9c DJ |
1063 | lp = add_lwp (new_ptid); |
1064 | lp->stopped = 1; | |
e26af52f | 1065 | |
2277426b PA |
1066 | /* This changes the thread's ptid while preserving the gdb thread |
1067 | num. Also changes the inferior pid, while preserving the | |
1068 | inferior num. */ | |
1069 | thread_change_ptid (inferior_ptid, new_ptid); | |
1070 | ||
1071 | /* We've just told GDB core that the thread changed target id, but, | |
1072 | in fact, it really is a different thread, with different register | |
1073 | contents. */ | |
1074 | registers_changed (); | |
e26af52f DJ |
1075 | } |
1076 | ||
e26af52f DJ |
1077 | /* Handle the exit of a single thread LP. */ |
1078 | ||
1079 | static void | |
1080 | exit_lwp (struct lwp_info *lp) | |
1081 | { | |
e09875d4 | 1082 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1083 | |
1084 | if (th) | |
e26af52f | 1085 | { |
17faa917 DJ |
1086 | if (print_thread_events) |
1087 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1088 | ||
4f8d22e3 | 1089 | delete_thread (lp->ptid); |
e26af52f DJ |
1090 | } |
1091 | ||
1092 | delete_lwp (lp->ptid); | |
1093 | } | |
1094 | ||
a0ef4274 DJ |
1095 | /* Wait for the LWP specified by LP, which we have just attached to. |
1096 | Returns a wait status for that LWP, to cache. */ | |
1097 | ||
1098 | static int | |
1099 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1100 | int *signalled) | |
1101 | { | |
dfd4cc63 | 1102 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
1103 | int status; |
1104 | ||
644cebc9 | 1105 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1106 | { |
1107 | if (debug_linux_nat) | |
1108 | fprintf_unfiltered (gdb_stdlog, | |
1109 | "LNPAW: Attaching to a stopped process\n"); | |
1110 | ||
1111 | /* The process is definitely stopped. It is in a job control | |
1112 | stop, unless the kernel predates the TASK_STOPPED / | |
1113 | TASK_TRACED distinction, in which case it might be in a | |
1114 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1115 | can kill it, signal it, et cetera. | |
1116 | ||
1117 | First make sure there is a pending SIGSTOP. Since we are | |
1118 | already attached, the process can not transition from stopped | |
1119 | to running without a PTRACE_CONT; so we know this signal will | |
1120 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1121 | probably already in the queue (unless this kernel is old | |
1122 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1123 | is not an RT signal, it can only be queued once. */ | |
1124 | kill_lwp (pid, SIGSTOP); | |
1125 | ||
1126 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1127 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1128 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1129 | } | |
1130 | ||
1131 | /* Make sure the initial process is stopped. The user-level threads | |
1132 | layer might want to poke around in the inferior, and that won't | |
1133 | work if things haven't stabilized yet. */ | |
1134 | new_pid = my_waitpid (pid, &status, 0); | |
1135 | if (new_pid == -1 && errno == ECHILD) | |
1136 | { | |
1137 | if (first) | |
1138 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1139 | ||
1140 | /* Try again with __WCLONE to check cloned processes. */ | |
1141 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1142 | *cloned = 1; | |
1143 | } | |
1144 | ||
dacc9cb2 PP |
1145 | gdb_assert (pid == new_pid); |
1146 | ||
1147 | if (!WIFSTOPPED (status)) | |
1148 | { | |
1149 | /* The pid we tried to attach has apparently just exited. */ | |
1150 | if (debug_linux_nat) | |
1151 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1152 | pid, status_to_str (status)); | |
1153 | return status; | |
1154 | } | |
a0ef4274 DJ |
1155 | |
1156 | if (WSTOPSIG (status) != SIGSTOP) | |
1157 | { | |
1158 | *signalled = 1; | |
1159 | if (debug_linux_nat) | |
1160 | fprintf_unfiltered (gdb_stdlog, | |
1161 | "LNPAW: Received %s after attaching\n", | |
1162 | status_to_str (status)); | |
1163 | } | |
1164 | ||
1165 | return status; | |
1166 | } | |
1167 | ||
84636d28 PA |
1168 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1169 | the new LWP could not be attached, or 1 if we're already auto | |
1170 | attached to this thread, but haven't processed the | |
1171 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1172 | its existance, without considering it an error. */ | |
d6b0e80f | 1173 | |
9ee57c33 | 1174 | int |
93815fbf | 1175 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1176 | { |
9ee57c33 | 1177 | struct lwp_info *lp; |
84636d28 | 1178 | int lwpid; |
d6b0e80f | 1179 | |
dfd4cc63 | 1180 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1181 | |
9ee57c33 | 1182 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1183 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f AC |
1184 | |
1185 | /* We assume that we're already attached to any LWP that has an id | |
1186 | equal to the overall process id, and to any LWP that is already | |
1187 | in our list of LWPs. If we're not seeing exit events from threads | |
1188 | and we've had PID wraparound since we last tried to stop all threads, | |
1189 | this assumption might be wrong; fortunately, this is very unlikely | |
1190 | to happen. */ | |
dfd4cc63 | 1191 | if (lwpid != ptid_get_pid (ptid) && lp == NULL) |
d6b0e80f | 1192 | { |
a0ef4274 | 1193 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1194 | |
84636d28 | 1195 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1196 | { |
96d7229d | 1197 | if (linux_supports_tracefork ()) |
84636d28 PA |
1198 | { |
1199 | /* If we haven't stopped all threads when we get here, | |
1200 | we may have seen a thread listed in thread_db's list, | |
1201 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1202 | that's the case, ignore this new thread, and let | |
1203 | normal event handling discover it later. */ | |
1204 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1205 | { | |
1206 | /* We've already seen this thread stop, but we | |
1207 | haven't seen the PTRACE_EVENT_CLONE extended | |
1208 | event yet. */ | |
84636d28 PA |
1209 | return 0; |
1210 | } | |
1211 | else | |
1212 | { | |
1213 | int new_pid; | |
1214 | int status; | |
1215 | ||
1216 | /* See if we've got a stop for this new child | |
1217 | pending. If so, we're already attached. */ | |
1218 | new_pid = my_waitpid (lwpid, &status, WNOHANG); | |
1219 | if (new_pid == -1 && errno == ECHILD) | |
1220 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1221 | if (new_pid != -1) | |
1222 | { | |
1223 | if (WIFSTOPPED (status)) | |
1224 | add_to_pid_list (&stopped_pids, lwpid, status); | |
84636d28 PA |
1225 | return 1; |
1226 | } | |
1227 | } | |
1228 | } | |
1229 | ||
9ee57c33 DJ |
1230 | /* If we fail to attach to the thread, issue a warning, |
1231 | but continue. One way this can happen is if thread | |
e9efe249 | 1232 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1233 | bug may place threads in the thread list and then fail |
1234 | to create them. */ | |
1235 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1236 | safe_strerror (errno)); | |
1237 | return -1; | |
1238 | } | |
1239 | ||
d6b0e80f AC |
1240 | if (debug_linux_nat) |
1241 | fprintf_unfiltered (gdb_stdlog, | |
1242 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1243 | target_pid_to_str (ptid)); | |
1244 | ||
a0ef4274 | 1245 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1246 | if (!WIFSTOPPED (status)) |
12696c10 | 1247 | return 1; |
dacc9cb2 | 1248 | |
a0ef4274 DJ |
1249 | lp = add_lwp (ptid); |
1250 | lp->stopped = 1; | |
1251 | lp->cloned = cloned; | |
1252 | lp->signalled = signalled; | |
1253 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1254 | { |
a0ef4274 DJ |
1255 | lp->resumed = 1; |
1256 | lp->status = status; | |
d6b0e80f AC |
1257 | } |
1258 | ||
dfd4cc63 | 1259 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1260 | |
1261 | if (debug_linux_nat) | |
1262 | { | |
1263 | fprintf_unfiltered (gdb_stdlog, | |
1264 | "LLAL: waitpid %s received %s\n", | |
1265 | target_pid_to_str (ptid), | |
1266 | status_to_str (status)); | |
1267 | } | |
1268 | } | |
1269 | else | |
1270 | { | |
1271 | /* We assume that the LWP representing the original process is | |
1272 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1273 | that the GNU/linux ptrace layer uses to keep track of |
1274 | threads. Note that this won't have already been done since | |
1275 | the main thread will have, we assume, been stopped by an | |
1276 | attach from a different layer. */ | |
9ee57c33 DJ |
1277 | if (lp == NULL) |
1278 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1279 | lp->stopped = 1; |
1280 | } | |
9ee57c33 | 1281 | |
25289eb2 | 1282 | lp->last_resume_kind = resume_stop; |
9ee57c33 | 1283 | return 0; |
d6b0e80f AC |
1284 | } |
1285 | ||
b84876c2 | 1286 | static void |
136d6dae VP |
1287 | linux_nat_create_inferior (struct target_ops *ops, |
1288 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1289 | int from_tty) |
1290 | { | |
10568435 JK |
1291 | #ifdef HAVE_PERSONALITY |
1292 | int personality_orig = 0, personality_set = 0; | |
1293 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1294 | |
1295 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1296 | we have to mask the async mode. */ | |
1297 | ||
10568435 JK |
1298 | #ifdef HAVE_PERSONALITY |
1299 | if (disable_randomization) | |
1300 | { | |
1301 | errno = 0; | |
1302 | personality_orig = personality (0xffffffff); | |
1303 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1304 | { | |
1305 | personality_set = 1; | |
1306 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1307 | } | |
1308 | if (errno != 0 || (personality_set | |
1309 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1310 | warning (_("Error disabling address space randomization: %s"), | |
1311 | safe_strerror (errno)); | |
1312 | } | |
1313 | #endif /* HAVE_PERSONALITY */ | |
1314 | ||
2455069d | 1315 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1316 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1317 | |
136d6dae | 1318 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1319 | |
10568435 JK |
1320 | #ifdef HAVE_PERSONALITY |
1321 | if (personality_set) | |
1322 | { | |
1323 | errno = 0; | |
1324 | personality (personality_orig); | |
1325 | if (errno != 0) | |
1326 | warning (_("Error restoring address space randomization: %s"), | |
1327 | safe_strerror (errno)); | |
1328 | } | |
1329 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1330 | } |
1331 | ||
d6b0e80f | 1332 | static void |
c0939df1 | 1333 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1334 | { |
1335 | struct lwp_info *lp; | |
d6b0e80f | 1336 | int status; |
af990527 | 1337 | ptid_t ptid; |
87b0bb13 | 1338 | volatile struct gdb_exception ex; |
d6b0e80f | 1339 | |
2455069d | 1340 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1341 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1342 | |
87b0bb13 JK |
1343 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
1344 | { | |
1345 | linux_ops->to_attach (ops, args, from_tty); | |
1346 | } | |
1347 | if (ex.reason < 0) | |
1348 | { | |
1349 | pid_t pid = parse_pid_to_attach (args); | |
1350 | struct buffer buffer; | |
1351 | char *message, *buffer_s; | |
1352 | ||
1353 | message = xstrdup (ex.message); | |
1354 | make_cleanup (xfree, message); | |
1355 | ||
1356 | buffer_init (&buffer); | |
7ae1a6a6 | 1357 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1358 | |
1359 | buffer_grow_str0 (&buffer, ""); | |
1360 | buffer_s = buffer_finish (&buffer); | |
1361 | make_cleanup (xfree, buffer_s); | |
1362 | ||
7ae1a6a6 PA |
1363 | if (*buffer_s != '\0') |
1364 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1365 | else | |
1366 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1367 | } |
d6b0e80f | 1368 | |
af990527 PA |
1369 | /* The ptrace base target adds the main thread with (pid,0,0) |
1370 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1371 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1372 | ptid_get_pid (inferior_ptid), | |
1373 | 0); | |
af990527 PA |
1374 | thread_change_ptid (inferior_ptid, ptid); |
1375 | ||
9f0bdab8 | 1376 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1377 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1378 | |
1379 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1380 | &lp->signalled); | |
dacc9cb2 PP |
1381 | if (!WIFSTOPPED (status)) |
1382 | { | |
1383 | if (WIFEXITED (status)) | |
1384 | { | |
1385 | int exit_code = WEXITSTATUS (status); | |
1386 | ||
1387 | target_terminal_ours (); | |
1388 | target_mourn_inferior (); | |
1389 | if (exit_code == 0) | |
1390 | error (_("Unable to attach: program exited normally.")); | |
1391 | else | |
1392 | error (_("Unable to attach: program exited with code %d."), | |
1393 | exit_code); | |
1394 | } | |
1395 | else if (WIFSIGNALED (status)) | |
1396 | { | |
2ea28649 | 1397 | enum gdb_signal signo; |
dacc9cb2 PP |
1398 | |
1399 | target_terminal_ours (); | |
1400 | target_mourn_inferior (); | |
1401 | ||
2ea28649 | 1402 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1403 | error (_("Unable to attach: program terminated with signal " |
1404 | "%s, %s."), | |
2ea28649 PA |
1405 | gdb_signal_to_name (signo), |
1406 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1407 | } |
1408 | ||
1409 | internal_error (__FILE__, __LINE__, | |
1410 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1411 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1412 | } |
1413 | ||
a0ef4274 | 1414 | lp->stopped = 1; |
9f0bdab8 | 1415 | |
a0ef4274 | 1416 | /* Save the wait status to report later. */ |
d6b0e80f | 1417 | lp->resumed = 1; |
a0ef4274 DJ |
1418 | if (debug_linux_nat) |
1419 | fprintf_unfiltered (gdb_stdlog, | |
1420 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1421 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1422 | |
7feb7d06 PA |
1423 | lp->status = status; |
1424 | ||
1425 | if (target_can_async_p ()) | |
1426 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1427 | } |
1428 | ||
a0ef4274 DJ |
1429 | /* Get pending status of LP. */ |
1430 | static int | |
1431 | get_pending_status (struct lwp_info *lp, int *status) | |
1432 | { | |
a493e3e2 | 1433 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1434 | |
1435 | /* If we paused threads momentarily, we may have stored pending | |
1436 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1437 | and GDB core hasn't seen any signal for those threads. | |
1438 | Otherwise, the last signal reported to the core is found in the | |
1439 | thread object's stop_signal. | |
1440 | ||
1441 | There's a corner case that isn't handled here at present. Only | |
1442 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1443 | stop_signal make sense as a real signal to pass to the inferior. | |
1444 | Some catchpoint related events, like | |
1445 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1446 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1447 | those traps are debug API (ptrace in our case) related and |
1448 | induced; the inferior wouldn't see them if it wasn't being | |
1449 | traced. Hence, we should never pass them to the inferior, even | |
1450 | when set to pass state. Since this corner case isn't handled by | |
1451 | infrun.c when proceeding with a signal, for consistency, neither | |
1452 | do we handle it here (or elsewhere in the file we check for | |
1453 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1454 | this is really a corner case. */ | |
1455 | ||
1456 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1457 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1458 | else if (lp->status) |
2ea28649 | 1459 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1460 | else if (non_stop && !is_executing (lp->ptid)) |
1461 | { | |
1462 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1463 | |
16c381f0 | 1464 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1465 | } |
1466 | else if (!non_stop) | |
a0ef4274 | 1467 | { |
ca2163eb PA |
1468 | struct target_waitstatus last; |
1469 | ptid_t last_ptid; | |
4c28f408 | 1470 | |
ca2163eb | 1471 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1472 | |
dfd4cc63 | 1473 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1474 | { |
e09875d4 | 1475 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1476 | |
16c381f0 | 1477 | signo = tp->suspend.stop_signal; |
4c28f408 | 1478 | } |
ca2163eb | 1479 | } |
4c28f408 | 1480 | |
ca2163eb | 1481 | *status = 0; |
4c28f408 | 1482 | |
a493e3e2 | 1483 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1484 | { |
1485 | if (debug_linux_nat) | |
1486 | fprintf_unfiltered (gdb_stdlog, | |
1487 | "GPT: lwp %s has no pending signal\n", | |
1488 | target_pid_to_str (lp->ptid)); | |
1489 | } | |
1490 | else if (!signal_pass_state (signo)) | |
1491 | { | |
1492 | if (debug_linux_nat) | |
3e43a32a MS |
1493 | fprintf_unfiltered (gdb_stdlog, |
1494 | "GPT: lwp %s had signal %s, " | |
1495 | "but it is in no pass state\n", | |
ca2163eb | 1496 | target_pid_to_str (lp->ptid), |
2ea28649 | 1497 | gdb_signal_to_string (signo)); |
a0ef4274 | 1498 | } |
a0ef4274 | 1499 | else |
4c28f408 | 1500 | { |
2ea28649 | 1501 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1502 | |
1503 | if (debug_linux_nat) | |
1504 | fprintf_unfiltered (gdb_stdlog, | |
1505 | "GPT: lwp %s has pending signal %s\n", | |
1506 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1507 | gdb_signal_to_string (signo)); |
4c28f408 | 1508 | } |
a0ef4274 DJ |
1509 | |
1510 | return 0; | |
1511 | } | |
1512 | ||
d6b0e80f AC |
1513 | static int |
1514 | detach_callback (struct lwp_info *lp, void *data) | |
1515 | { | |
1516 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1517 | ||
1518 | if (debug_linux_nat && lp->status) | |
1519 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1520 | strsignal (WSTOPSIG (lp->status)), | |
1521 | target_pid_to_str (lp->ptid)); | |
1522 | ||
a0ef4274 DJ |
1523 | /* If there is a pending SIGSTOP, get rid of it. */ |
1524 | if (lp->signalled) | |
d6b0e80f | 1525 | { |
d6b0e80f AC |
1526 | if (debug_linux_nat) |
1527 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1528 | "DC: Sending SIGCONT to %s\n", |
1529 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1530 | |
dfd4cc63 | 1531 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1532 | lp->signalled = 0; |
d6b0e80f AC |
1533 | } |
1534 | ||
1535 | /* We don't actually detach from the LWP that has an id equal to the | |
1536 | overall process id just yet. */ | |
dfd4cc63 | 1537 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1538 | { |
a0ef4274 DJ |
1539 | int status = 0; |
1540 | ||
1541 | /* Pass on any pending signal for this LWP. */ | |
1542 | get_pending_status (lp, &status); | |
1543 | ||
7b50312a PA |
1544 | if (linux_nat_prepare_to_resume != NULL) |
1545 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1546 | errno = 0; |
dfd4cc63 | 1547 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1548 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1549 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1550 | safe_strerror (errno)); |
1551 | ||
1552 | if (debug_linux_nat) | |
1553 | fprintf_unfiltered (gdb_stdlog, | |
1554 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1555 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1556 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1557 | |
1558 | delete_lwp (lp->ptid); | |
1559 | } | |
1560 | ||
1561 | return 0; | |
1562 | } | |
1563 | ||
1564 | static void | |
52554a0e | 1565 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1566 | { |
b84876c2 | 1567 | int pid; |
a0ef4274 | 1568 | int status; |
d90e17a7 PA |
1569 | struct lwp_info *main_lwp; |
1570 | ||
dfd4cc63 | 1571 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1572 | |
ae5e0686 MK |
1573 | /* Don't unregister from the event loop, as there may be other |
1574 | inferiors running. */ | |
b84876c2 | 1575 | |
4c28f408 PA |
1576 | /* Stop all threads before detaching. ptrace requires that the |
1577 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1578 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1579 | /* ... and wait until all of them have reported back that |
1580 | they're no longer running. */ | |
d90e17a7 | 1581 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1582 | |
d90e17a7 | 1583 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1584 | |
1585 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1586 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1587 | |
1588 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1589 | |
a0ef4274 DJ |
1590 | /* Pass on any pending signal for the last LWP. */ |
1591 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1592 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1593 | && WIFSTOPPED (status)) |
1594 | { | |
52554a0e TT |
1595 | char *tem; |
1596 | ||
a0ef4274 DJ |
1597 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1598 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1599 | tem = alloca (8); |
cde33bf1 | 1600 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1601 | args = tem; |
ddabfc73 TT |
1602 | if (debug_linux_nat) |
1603 | fprintf_unfiltered (gdb_stdlog, | |
1604 | "LND: Sending signal %s to %s\n", | |
1605 | args, | |
1606 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1607 | } |
1608 | ||
7b50312a PA |
1609 | if (linux_nat_prepare_to_resume != NULL) |
1610 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1611 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1612 | |
7a7d3353 PA |
1613 | if (forks_exist_p ()) |
1614 | { | |
1615 | /* Multi-fork case. The current inferior_ptid is being detached | |
1616 | from, but there are other viable forks to debug. Detach from | |
1617 | the current fork, and context-switch to the first | |
1618 | available. */ | |
1619 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1620 | } |
1621 | else | |
1622 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1623 | } |
1624 | ||
1625 | /* Resume LP. */ | |
1626 | ||
25289eb2 | 1627 | static void |
e5ef252a | 1628 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1629 | { |
25289eb2 | 1630 | if (lp->stopped) |
6c95b8df | 1631 | { |
dfd4cc63 | 1632 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
25289eb2 PA |
1633 | |
1634 | if (inf->vfork_child != NULL) | |
1635 | { | |
1636 | if (debug_linux_nat) | |
1637 | fprintf_unfiltered (gdb_stdlog, | |
1638 | "RC: Not resuming %s (vfork parent)\n", | |
1639 | target_pid_to_str (lp->ptid)); | |
1640 | } | |
1641 | else if (lp->status == 0 | |
1642 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
1643 | { | |
1644 | if (debug_linux_nat) | |
1645 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1646 | "RC: Resuming sibling %s, %s, %s\n", |
1647 | target_pid_to_str (lp->ptid), | |
1648 | (signo != GDB_SIGNAL_0 | |
1649 | ? strsignal (gdb_signal_to_host (signo)) | |
1650 | : "0"), | |
1651 | step ? "step" : "resume"); | |
25289eb2 | 1652 | |
7b50312a PA |
1653 | if (linux_nat_prepare_to_resume != NULL) |
1654 | linux_nat_prepare_to_resume (lp); | |
25289eb2 | 1655 | linux_ops->to_resume (linux_ops, |
dfd4cc63 | 1656 | pid_to_ptid (ptid_get_lwp (lp->ptid)), |
e5ef252a | 1657 | step, signo); |
25289eb2 PA |
1658 | lp->stopped = 0; |
1659 | lp->step = step; | |
25289eb2 PA |
1660 | lp->stopped_by_watchpoint = 0; |
1661 | } | |
1662 | else | |
1663 | { | |
1664 | if (debug_linux_nat) | |
1665 | fprintf_unfiltered (gdb_stdlog, | |
1666 | "RC: Not resuming sibling %s (has pending)\n", | |
1667 | target_pid_to_str (lp->ptid)); | |
1668 | } | |
6c95b8df | 1669 | } |
25289eb2 | 1670 | else |
d6b0e80f | 1671 | { |
d90e17a7 PA |
1672 | if (debug_linux_nat) |
1673 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1674 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1675 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1676 | } |
25289eb2 | 1677 | } |
d6b0e80f | 1678 | |
8817a6f2 PA |
1679 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1680 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1681 | |
25289eb2 | 1682 | static int |
8817a6f2 | 1683 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1684 | { |
e5ef252a PA |
1685 | enum gdb_signal signo = GDB_SIGNAL_0; |
1686 | ||
8817a6f2 PA |
1687 | if (lp == except) |
1688 | return 0; | |
1689 | ||
e5ef252a PA |
1690 | if (lp->stopped) |
1691 | { | |
1692 | struct thread_info *thread; | |
1693 | ||
1694 | thread = find_thread_ptid (lp->ptid); | |
1695 | if (thread != NULL) | |
1696 | { | |
1697 | if (signal_pass_state (thread->suspend.stop_signal)) | |
1698 | signo = thread->suspend.stop_signal; | |
1699 | thread->suspend.stop_signal = GDB_SIGNAL_0; | |
1700 | } | |
1701 | } | |
1702 | ||
1703 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1704 | return 0; |
1705 | } | |
1706 | ||
1707 | static int | |
1708 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1709 | { | |
1710 | lp->resumed = 0; | |
25289eb2 | 1711 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1712 | return 0; |
1713 | } | |
1714 | ||
1715 | static int | |
1716 | resume_set_callback (struct lwp_info *lp, void *data) | |
1717 | { | |
1718 | lp->resumed = 1; | |
25289eb2 | 1719 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1720 | return 0; |
1721 | } | |
1722 | ||
1723 | static void | |
28439f5e | 1724 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1725 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1726 | { |
1727 | struct lwp_info *lp; | |
d90e17a7 | 1728 | int resume_many; |
d6b0e80f | 1729 | |
76f50ad1 DJ |
1730 | if (debug_linux_nat) |
1731 | fprintf_unfiltered (gdb_stdlog, | |
1732 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1733 | step ? "step" : "resume", | |
1734 | target_pid_to_str (ptid), | |
a493e3e2 | 1735 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1736 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1737 | target_pid_to_str (inferior_ptid)); |
1738 | ||
d6b0e80f | 1739 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1740 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1741 | || ptid_is_pid (ptid)); | |
4c28f408 | 1742 | |
e3e9f5a2 PA |
1743 | /* Mark the lwps we're resuming as resumed. */ |
1744 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1745 | |
d90e17a7 PA |
1746 | /* See if it's the current inferior that should be handled |
1747 | specially. */ | |
1748 | if (resume_many) | |
1749 | lp = find_lwp_pid (inferior_ptid); | |
1750 | else | |
1751 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1752 | gdb_assert (lp != NULL); |
d6b0e80f | 1753 | |
9f0bdab8 DJ |
1754 | /* Remember if we're stepping. */ |
1755 | lp->step = step; | |
25289eb2 | 1756 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1757 | |
9f0bdab8 DJ |
1758 | /* If we have a pending wait status for this thread, there is no |
1759 | point in resuming the process. But first make sure that | |
1760 | linux_nat_wait won't preemptively handle the event - we | |
1761 | should never take this short-circuit if we are going to | |
1762 | leave LP running, since we have skipped resuming all the | |
1763 | other threads. This bit of code needs to be synchronized | |
1764 | with linux_nat_wait. */ | |
76f50ad1 | 1765 | |
9f0bdab8 DJ |
1766 | if (lp->status && WIFSTOPPED (lp->status)) |
1767 | { | |
2455069d UW |
1768 | if (!lp->step |
1769 | && WSTOPSIG (lp->status) | |
1770 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1771 | { |
9f0bdab8 DJ |
1772 | if (debug_linux_nat) |
1773 | fprintf_unfiltered (gdb_stdlog, | |
1774 | "LLR: Not short circuiting for ignored " | |
1775 | "status 0x%x\n", lp->status); | |
1776 | ||
d6b0e80f AC |
1777 | /* FIXME: What should we do if we are supposed to continue |
1778 | this thread with a signal? */ | |
a493e3e2 | 1779 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1780 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1781 | lp->status = 0; |
1782 | } | |
1783 | } | |
76f50ad1 | 1784 | |
6c95b8df | 1785 | if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) |
9f0bdab8 DJ |
1786 | { |
1787 | /* FIXME: What should we do if we are supposed to continue | |
1788 | this thread with a signal? */ | |
a493e3e2 | 1789 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1790 | |
9f0bdab8 DJ |
1791 | if (debug_linux_nat) |
1792 | fprintf_unfiltered (gdb_stdlog, | |
1793 | "LLR: Short circuiting for status 0x%x\n", | |
1794 | lp->status); | |
d6b0e80f | 1795 | |
7feb7d06 PA |
1796 | if (target_can_async_p ()) |
1797 | { | |
1798 | target_async (inferior_event_handler, 0); | |
1799 | /* Tell the event loop we have something to process. */ | |
1800 | async_file_mark (); | |
1801 | } | |
9f0bdab8 | 1802 | return; |
d6b0e80f AC |
1803 | } |
1804 | ||
d90e17a7 | 1805 | if (resume_many) |
8817a6f2 | 1806 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 PA |
1807 | |
1808 | /* Convert to something the lower layer understands. */ | |
dfd4cc63 | 1809 | ptid = pid_to_ptid (ptid_get_lwp (lp->ptid)); |
d6b0e80f | 1810 | |
7b50312a PA |
1811 | if (linux_nat_prepare_to_resume != NULL) |
1812 | linux_nat_prepare_to_resume (lp); | |
28439f5e | 1813 | linux_ops->to_resume (linux_ops, ptid, step, signo); |
ebec9a0f | 1814 | lp->stopped_by_watchpoint = 0; |
8817a6f2 | 1815 | lp->stopped = 0; |
9f0bdab8 | 1816 | |
d6b0e80f AC |
1817 | if (debug_linux_nat) |
1818 | fprintf_unfiltered (gdb_stdlog, | |
1819 | "LLR: %s %s, %s (resume event thread)\n", | |
1820 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1821 | target_pid_to_str (ptid), | |
a493e3e2 | 1822 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1823 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1824 | |
1825 | if (target_can_async_p ()) | |
8ea051c5 | 1826 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1827 | } |
1828 | ||
c5f62d5f | 1829 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1830 | |
1831 | static int | |
1832 | kill_lwp (int lwpid, int signo) | |
1833 | { | |
c5f62d5f DE |
1834 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1835 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1836 | |
1837 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1838 | { |
1839 | static int tkill_failed; | |
1840 | ||
1841 | if (!tkill_failed) | |
1842 | { | |
1843 | int ret; | |
1844 | ||
1845 | errno = 0; | |
1846 | ret = syscall (__NR_tkill, lwpid, signo); | |
1847 | if (errno != ENOSYS) | |
1848 | return ret; | |
1849 | tkill_failed = 1; | |
1850 | } | |
1851 | } | |
d6b0e80f AC |
1852 | #endif |
1853 | ||
1854 | return kill (lwpid, signo); | |
1855 | } | |
1856 | ||
ca2163eb PA |
1857 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1858 | event, check if the core is interested in it: if not, ignore the | |
1859 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1860 | syscall entry/exit status, since the ptrace event itself doesn't | |
1861 | indicate it, and report the trap to higher layers. */ | |
1862 | ||
1863 | static int | |
1864 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1865 | { | |
1866 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1867 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1868 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1869 | ||
1870 | if (stopping) | |
1871 | { | |
1872 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1873 | makes it so that the LWP reports an immediate syscall return, | |
1874 | followed by the SIGSTOP. Skip seeing that "return" using | |
1875 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1876 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1877 | entry event. If we didn't do this (and returned 0), we'd | |
1878 | leave a syscall entry pending, and our caller, by using | |
1879 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1880 | itself. Later, when the user re-resumes this LWP, we'd see | |
1881 | another syscall entry event and we'd mistake it for a return. | |
1882 | ||
1883 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1884 | (leaving immediately with LWP->signalled set, without issuing | |
1885 | a PTRACE_CONT), it would still be problematic to leave this | |
1886 | syscall enter pending, as later when the thread is resumed, | |
1887 | it would then see the same syscall exit mentioned above, | |
1888 | followed by the delayed SIGSTOP, while the syscall didn't | |
1889 | actually get to execute. It seems it would be even more | |
1890 | confusing to the user. */ | |
1891 | ||
1892 | if (debug_linux_nat) | |
1893 | fprintf_unfiltered (gdb_stdlog, | |
1894 | "LHST: ignoring syscall %d " | |
1895 | "for LWP %ld (stopping threads), " | |
1896 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1897 | syscall_number, | |
dfd4cc63 | 1898 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1899 | |
1900 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1901 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1902 | lp->stopped = 0; |
ca2163eb PA |
1903 | return 1; |
1904 | } | |
1905 | ||
1906 | if (catch_syscall_enabled ()) | |
1907 | { | |
1908 | /* Always update the entry/return state, even if this particular | |
1909 | syscall isn't interesting to the core now. In async mode, | |
1910 | the user could install a new catchpoint for this syscall | |
1911 | between syscall enter/return, and we'll need to know to | |
1912 | report a syscall return if that happens. */ | |
1913 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1914 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1915 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1916 | ||
1917 | if (catching_syscall_number (syscall_number)) | |
1918 | { | |
1919 | /* Alright, an event to report. */ | |
1920 | ourstatus->kind = lp->syscall_state; | |
1921 | ourstatus->value.syscall_number = syscall_number; | |
1922 | ||
1923 | if (debug_linux_nat) | |
1924 | fprintf_unfiltered (gdb_stdlog, | |
1925 | "LHST: stopping for %s of syscall %d" | |
1926 | " for LWP %ld\n", | |
3e43a32a MS |
1927 | lp->syscall_state |
1928 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1929 | ? "entry" : "return", |
1930 | syscall_number, | |
dfd4cc63 | 1931 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1932 | return 0; |
1933 | } | |
1934 | ||
1935 | if (debug_linux_nat) | |
1936 | fprintf_unfiltered (gdb_stdlog, | |
1937 | "LHST: ignoring %s of syscall %d " | |
1938 | "for LWP %ld\n", | |
1939 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1940 | ? "entry" : "return", | |
1941 | syscall_number, | |
dfd4cc63 | 1942 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1943 | } |
1944 | else | |
1945 | { | |
1946 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1947 | before on this LWP, it could happen that the user removes all | |
1948 | syscall catchpoints before we get to process this event. | |
1949 | There are two noteworthy issues here: | |
1950 | ||
1951 | - When stopped at a syscall entry event, resuming with | |
1952 | PT_STEP still resumes executing the syscall and reports a | |
1953 | syscall return. | |
1954 | ||
1955 | - Only PT_SYSCALL catches syscall enters. If we last | |
1956 | single-stepped this thread, then this event can't be a | |
1957 | syscall enter. If we last single-stepped this thread, this | |
1958 | has to be a syscall exit. | |
1959 | ||
1960 | The points above mean that the next resume, be it PT_STEP or | |
1961 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1962 | if (debug_linux_nat) | |
1963 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1964 | "LHST: caught syscall event " |
1965 | "with no syscall catchpoints." | |
ca2163eb PA |
1966 | " %d for LWP %ld, ignoring\n", |
1967 | syscall_number, | |
dfd4cc63 | 1968 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1969 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1970 | } | |
1971 | ||
1972 | /* The core isn't interested in this event. For efficiency, avoid | |
1973 | stopping all threads only to have the core resume them all again. | |
1974 | Since we're not stopping threads, if we're still syscall tracing | |
1975 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1976 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1977 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1978 | ||
1979 | /* Note that gdbarch_get_syscall_number may access registers, hence | |
1980 | fill a regcache. */ | |
1981 | registers_changed (); | |
7b50312a PA |
1982 | if (linux_nat_prepare_to_resume != NULL) |
1983 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 1984 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 1985 | lp->step, GDB_SIGNAL_0); |
8817a6f2 | 1986 | lp->stopped = 0; |
ca2163eb PA |
1987 | return 1; |
1988 | } | |
1989 | ||
3d799a95 DJ |
1990 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1991 | event, we need to add the new LWP to our list (and not report the | |
1992 | trap to higher layers). This function returns non-zero if the | |
1993 | event should be ignored and we should wait again. If STOPPING is | |
1994 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1995 | |
1996 | static int | |
3d799a95 DJ |
1997 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1998 | int stopping) | |
d6b0e80f | 1999 | { |
dfd4cc63 | 2000 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 2001 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
3d799a95 | 2002 | int event = status >> 16; |
d6b0e80f | 2003 | |
3d799a95 DJ |
2004 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
2005 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 2006 | { |
3d799a95 DJ |
2007 | unsigned long new_pid; |
2008 | int ret; | |
2009 | ||
2010 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 2011 | |
3d799a95 DJ |
2012 | /* If we haven't already seen the new PID stop, wait for it now. */ |
2013 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2014 | { | |
2015 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2016 | hits the SIGSTOP, but we're already attached. */ | |
2017 | ret = my_waitpid (new_pid, &status, | |
2018 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2019 | if (ret == -1) | |
2020 | perror_with_name (_("waiting for new child")); | |
2021 | else if (ret != new_pid) | |
2022 | internal_error (__FILE__, __LINE__, | |
2023 | _("wait returned unexpected PID %d"), ret); | |
2024 | else if (!WIFSTOPPED (status)) | |
2025 | internal_error (__FILE__, __LINE__, | |
2026 | _("wait returned unexpected status 0x%x"), status); | |
2027 | } | |
2028 | ||
3a3e9ee3 | 2029 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2030 | |
26cb8b7c PA |
2031 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2032 | { | |
2033 | /* The arch-specific native code may need to know about new | |
2034 | forks even if those end up never mapped to an | |
2035 | inferior. */ | |
2036 | if (linux_nat_new_fork != NULL) | |
2037 | linux_nat_new_fork (lp, new_pid); | |
2038 | } | |
2039 | ||
2277426b | 2040 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2041 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2042 | { |
2277426b PA |
2043 | /* Handle checkpointing by linux-fork.c here as a special |
2044 | case. We don't want the follow-fork-mode or 'catch fork' | |
2045 | to interfere with this. */ | |
2046 | ||
2047 | /* This won't actually modify the breakpoint list, but will | |
2048 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2049 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2050 | |
2051 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2052 | if (!find_fork_pid (new_pid)) |
2053 | add_fork (new_pid); | |
2277426b PA |
2054 | |
2055 | /* Report as spurious, so that infrun doesn't want to follow | |
2056 | this fork. We're actually doing an infcall in | |
2057 | linux-fork.c. */ | |
2058 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2059 | |
2060 | /* Report the stop to the core. */ | |
2061 | return 0; | |
2062 | } | |
2063 | ||
3d799a95 DJ |
2064 | if (event == PTRACE_EVENT_FORK) |
2065 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2066 | else if (event == PTRACE_EVENT_VFORK) | |
2067 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2068 | else |
3d799a95 | 2069 | { |
78768c4a JK |
2070 | struct lwp_info *new_lp; |
2071 | ||
3d799a95 | 2072 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2073 | |
3c4d7e12 PA |
2074 | if (debug_linux_nat) |
2075 | fprintf_unfiltered (gdb_stdlog, | |
2076 | "LHEW: Got clone event " | |
2077 | "from LWP %d, new child is LWP %ld\n", | |
2078 | pid, new_pid); | |
2079 | ||
dfd4cc63 | 2080 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2081 | new_lp->cloned = 1; |
4c28f408 | 2082 | new_lp->stopped = 1; |
d6b0e80f | 2083 | |
3d799a95 DJ |
2084 | if (WSTOPSIG (status) != SIGSTOP) |
2085 | { | |
2086 | /* This can happen if someone starts sending signals to | |
2087 | the new thread before it gets a chance to run, which | |
2088 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2089 | This is an unlikely case, and harder to handle for | |
2090 | fork / vfork than for clone, so we do not try - but | |
2091 | we handle it for clone events here. We'll send | |
2092 | the other signal on to the thread below. */ | |
2093 | ||
2094 | new_lp->signalled = 1; | |
2095 | } | |
2096 | else | |
79395f92 PA |
2097 | { |
2098 | struct thread_info *tp; | |
2099 | ||
2100 | /* When we stop for an event in some other thread, and | |
2101 | pull the thread list just as this thread has cloned, | |
2102 | we'll have seen the new thread in the thread_db list | |
2103 | before handling the CLONE event (glibc's | |
2104 | pthread_create adds the new thread to the thread list | |
2105 | before clone'ing, and has the kernel fill in the | |
2106 | thread's tid on the clone call with | |
2107 | CLONE_PARENT_SETTID). If that happened, and the core | |
2108 | had requested the new thread to stop, we'll have | |
2109 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2110 | RT signal, it can only be queued once. We need to be | |
2111 | careful to not resume the LWP if we wanted it to | |
2112 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2113 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2114 | tp = find_thread_ptid (new_lp->ptid); |
2115 | if (tp != NULL && tp->stop_requested) | |
2116 | new_lp->last_resume_kind = resume_stop; | |
2117 | else | |
2118 | status = 0; | |
2119 | } | |
d6b0e80f | 2120 | |
4c28f408 | 2121 | if (non_stop) |
3d799a95 | 2122 | { |
4c28f408 PA |
2123 | /* Add the new thread to GDB's lists as soon as possible |
2124 | so that: | |
2125 | ||
2126 | 1) the frontend doesn't have to wait for a stop to | |
2127 | display them, and, | |
2128 | ||
2129 | 2) we tag it with the correct running state. */ | |
2130 | ||
2131 | /* If the thread_db layer is active, let it know about | |
2132 | this new thread, and add it to GDB's list. */ | |
2133 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
2134 | { | |
2135 | /* We're not using thread_db. Add it to GDB's | |
2136 | list. */ | |
dfd4cc63 | 2137 | target_post_attach (ptid_get_lwp (new_lp->ptid)); |
4c28f408 PA |
2138 | add_thread (new_lp->ptid); |
2139 | } | |
2140 | ||
2141 | if (!stopping) | |
2142 | { | |
2143 | set_running (new_lp->ptid, 1); | |
2144 | set_executing (new_lp->ptid, 1); | |
e21ffe51 PA |
2145 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced |
2146 | resume_stop. */ | |
2147 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2148 | } |
2149 | } | |
2150 | ||
79395f92 PA |
2151 | if (status != 0) |
2152 | { | |
2153 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2154 | gdb_assert (new_lp->status == 0); | |
2155 | ||
2156 | /* Save the wait status to report later. */ | |
2157 | if (debug_linux_nat) | |
2158 | fprintf_unfiltered (gdb_stdlog, | |
2159 | "LHEW: waitpid of new LWP %ld, " | |
2160 | "saving status %s\n", | |
dfd4cc63 | 2161 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2162 | status_to_str (status)); |
2163 | new_lp->status = status; | |
2164 | } | |
2165 | ||
ca2163eb PA |
2166 | /* Note the need to use the low target ops to resume, to |
2167 | handle resuming with PT_SYSCALL if we have syscall | |
2168 | catchpoints. */ | |
4c28f408 PA |
2169 | if (!stopping) |
2170 | { | |
3d799a95 | 2171 | new_lp->resumed = 1; |
ca2163eb | 2172 | |
79395f92 | 2173 | if (status == 0) |
ad34eb2f | 2174 | { |
e21ffe51 | 2175 | gdb_assert (new_lp->last_resume_kind == resume_continue); |
ad34eb2f JK |
2176 | if (debug_linux_nat) |
2177 | fprintf_unfiltered (gdb_stdlog, | |
79395f92 | 2178 | "LHEW: resuming new LWP %ld\n", |
dfd4cc63 | 2179 | ptid_get_lwp (new_lp->ptid)); |
7b50312a PA |
2180 | if (linux_nat_prepare_to_resume != NULL) |
2181 | linux_nat_prepare_to_resume (new_lp); | |
79395f92 | 2182 | linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid), |
a493e3e2 | 2183 | 0, GDB_SIGNAL_0); |
79395f92 | 2184 | new_lp->stopped = 0; |
ad34eb2f JK |
2185 | } |
2186 | } | |
d6b0e80f | 2187 | |
3d799a95 DJ |
2188 | if (debug_linux_nat) |
2189 | fprintf_unfiltered (gdb_stdlog, | |
3c4d7e12 | 2190 | "LHEW: resuming parent LWP %d\n", pid); |
7b50312a PA |
2191 | if (linux_nat_prepare_to_resume != NULL) |
2192 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
2193 | linux_ops->to_resume (linux_ops, |
2194 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
a493e3e2 | 2195 | 0, GDB_SIGNAL_0); |
8817a6f2 | 2196 | lp->stopped = 0; |
3d799a95 DJ |
2197 | return 1; |
2198 | } | |
2199 | ||
2200 | return 0; | |
d6b0e80f AC |
2201 | } |
2202 | ||
3d799a95 DJ |
2203 | if (event == PTRACE_EVENT_EXEC) |
2204 | { | |
a75724bc PA |
2205 | if (debug_linux_nat) |
2206 | fprintf_unfiltered (gdb_stdlog, | |
2207 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2208 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2209 | |
3d799a95 DJ |
2210 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2211 | ourstatus->value.execd_pathname | |
8dd27370 | 2212 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2213 | |
6c95b8df PA |
2214 | return 0; |
2215 | } | |
2216 | ||
2217 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2218 | { | |
2219 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2220 | { |
6c95b8df | 2221 | if (debug_linux_nat) |
3e43a32a MS |
2222 | fprintf_unfiltered (gdb_stdlog, |
2223 | "LHEW: Got expected PTRACE_EVENT_" | |
2224 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2225 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2226 | |
6c95b8df PA |
2227 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2228 | return 0; | |
3d799a95 DJ |
2229 | } |
2230 | ||
6c95b8df | 2231 | if (debug_linux_nat) |
3e43a32a MS |
2232 | fprintf_unfiltered (gdb_stdlog, |
2233 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
2234 | "from LWP %ld: resuming\n", | |
dfd4cc63 LM |
2235 | ptid_get_lwp (lp->ptid)); |
2236 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); | |
6c95b8df | 2237 | return 1; |
3d799a95 DJ |
2238 | } |
2239 | ||
2240 | internal_error (__FILE__, __LINE__, | |
2241 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2242 | } |
2243 | ||
2244 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2245 | exited. */ | |
2246 | ||
2247 | static int | |
2248 | wait_lwp (struct lwp_info *lp) | |
2249 | { | |
2250 | pid_t pid; | |
432b4d03 | 2251 | int status = 0; |
d6b0e80f | 2252 | int thread_dead = 0; |
432b4d03 | 2253 | sigset_t prev_mask; |
d6b0e80f AC |
2254 | |
2255 | gdb_assert (!lp->stopped); | |
2256 | gdb_assert (lp->status == 0); | |
2257 | ||
432b4d03 JK |
2258 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2259 | block_child_signals (&prev_mask); | |
2260 | ||
2261 | for (;;) | |
d6b0e80f | 2262 | { |
432b4d03 JK |
2263 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2264 | was right and we should just call sigsuspend. */ | |
2265 | ||
dfd4cc63 | 2266 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2267 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2268 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2269 | if (pid == -1 && errno == ECHILD) |
2270 | { | |
2271 | /* The thread has previously exited. We need to delete it | |
2272 | now because, for some vendor 2.4 kernels with NPTL | |
2273 | support backported, there won't be an exit event unless | |
2274 | it is the main thread. 2.6 kernels will report an exit | |
2275 | event for each thread that exits, as expected. */ | |
2276 | thread_dead = 1; | |
2277 | if (debug_linux_nat) | |
2278 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2279 | target_pid_to_str (lp->ptid)); | |
2280 | } | |
432b4d03 JK |
2281 | if (pid != 0) |
2282 | break; | |
2283 | ||
2284 | /* Bugs 10970, 12702. | |
2285 | Thread group leader may have exited in which case we'll lock up in | |
2286 | waitpid if there are other threads, even if they are all zombies too. | |
2287 | Basically, we're not supposed to use waitpid this way. | |
2288 | __WCLONE is not applicable for the leader so we can't use that. | |
2289 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2290 | process; it gets ESRCH both for the zombie and for running processes. | |
2291 | ||
2292 | As a workaround, check if we're waiting for the thread group leader and | |
2293 | if it's a zombie, and avoid calling waitpid if it is. | |
2294 | ||
2295 | This is racy, what if the tgl becomes a zombie right after we check? | |
2296 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2297 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2298 | |
dfd4cc63 LM |
2299 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2300 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2301 | { |
d6b0e80f AC |
2302 | thread_dead = 1; |
2303 | if (debug_linux_nat) | |
432b4d03 JK |
2304 | fprintf_unfiltered (gdb_stdlog, |
2305 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2306 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2307 | break; |
d6b0e80f | 2308 | } |
432b4d03 JK |
2309 | |
2310 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2311 | get invoked despite our caller had them intentionally blocked by | |
2312 | block_child_signals. This is sensitive only to the loop of | |
2313 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2314 | again before it gets to sigsuspend so we can safely let the handlers | |
2315 | get executed here. */ | |
2316 | ||
2317 | sigsuspend (&suspend_mask); | |
2318 | } | |
2319 | ||
2320 | restore_child_signals_mask (&prev_mask); | |
2321 | ||
d6b0e80f AC |
2322 | if (!thread_dead) |
2323 | { | |
dfd4cc63 | 2324 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2325 | |
2326 | if (debug_linux_nat) | |
2327 | { | |
2328 | fprintf_unfiltered (gdb_stdlog, | |
2329 | "WL: waitpid %s received %s\n", | |
2330 | target_pid_to_str (lp->ptid), | |
2331 | status_to_str (status)); | |
2332 | } | |
d6b0e80f | 2333 | |
a9f4bb21 PA |
2334 | /* Check if the thread has exited. */ |
2335 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2336 | { | |
2337 | thread_dead = 1; | |
2338 | if (debug_linux_nat) | |
2339 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2340 | target_pid_to_str (lp->ptid)); | |
2341 | } | |
d6b0e80f AC |
2342 | } |
2343 | ||
2344 | if (thread_dead) | |
2345 | { | |
e26af52f | 2346 | exit_lwp (lp); |
d6b0e80f AC |
2347 | return 0; |
2348 | } | |
2349 | ||
2350 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2351 | lp->stopped = 1; |
d6b0e80f | 2352 | |
ca2163eb PA |
2353 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2354 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2355 | { | |
2356 | /* No longer need the sysgood bit. The ptrace event ends up | |
2357 | recorded in lp->waitstatus if we care for it. We can carry | |
2358 | on handling the event like a regular SIGTRAP from here | |
2359 | on. */ | |
2360 | status = W_STOPCODE (SIGTRAP); | |
2361 | if (linux_handle_syscall_trap (lp, 1)) | |
2362 | return wait_lwp (lp); | |
2363 | } | |
2364 | ||
d6b0e80f AC |
2365 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2366 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2367 | { | |
2368 | if (debug_linux_nat) | |
2369 | fprintf_unfiltered (gdb_stdlog, | |
2370 | "WL: Handling extended status 0x%06x\n", | |
2371 | status); | |
3d799a95 | 2372 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
2373 | return wait_lwp (lp); |
2374 | } | |
2375 | ||
2376 | return status; | |
2377 | } | |
2378 | ||
2379 | /* Send a SIGSTOP to LP. */ | |
2380 | ||
2381 | static int | |
2382 | stop_callback (struct lwp_info *lp, void *data) | |
2383 | { | |
2384 | if (!lp->stopped && !lp->signalled) | |
2385 | { | |
2386 | int ret; | |
2387 | ||
2388 | if (debug_linux_nat) | |
2389 | { | |
2390 | fprintf_unfiltered (gdb_stdlog, | |
2391 | "SC: kill %s **<SIGSTOP>**\n", | |
2392 | target_pid_to_str (lp->ptid)); | |
2393 | } | |
2394 | errno = 0; | |
dfd4cc63 | 2395 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2396 | if (debug_linux_nat) |
2397 | { | |
2398 | fprintf_unfiltered (gdb_stdlog, | |
2399 | "SC: lwp kill %d %s\n", | |
2400 | ret, | |
2401 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2402 | } | |
2403 | ||
2404 | lp->signalled = 1; | |
2405 | gdb_assert (lp->status == 0); | |
2406 | } | |
2407 | ||
2408 | return 0; | |
2409 | } | |
2410 | ||
7b50312a PA |
2411 | /* Request a stop on LWP. */ |
2412 | ||
2413 | void | |
2414 | linux_stop_lwp (struct lwp_info *lwp) | |
2415 | { | |
2416 | stop_callback (lwp, NULL); | |
2417 | } | |
2418 | ||
57380f4e | 2419 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2420 | |
2421 | static int | |
57380f4e DJ |
2422 | linux_nat_has_pending_sigint (int pid) |
2423 | { | |
2424 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2425 | |
2426 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2427 | ||
2428 | if (sigismember (&pending, SIGINT) | |
2429 | && !sigismember (&ignored, SIGINT)) | |
2430 | return 1; | |
2431 | ||
2432 | return 0; | |
2433 | } | |
2434 | ||
2435 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2436 | ||
2437 | static int | |
2438 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2439 | { |
57380f4e DJ |
2440 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2441 | flag to consume the next one. */ | |
2442 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2443 | && WSTOPSIG (lp->status) == SIGINT) | |
2444 | lp->status = 0; | |
2445 | else | |
2446 | lp->ignore_sigint = 1; | |
2447 | ||
2448 | return 0; | |
2449 | } | |
2450 | ||
2451 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2452 | This function is called after we know the LWP has stopped; if the LWP | |
2453 | stopped before the expected SIGINT was delivered, then it will never have | |
2454 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2455 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2456 | |
57380f4e DJ |
2457 | static void |
2458 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2459 | { | |
2460 | if (!lp->ignore_sigint) | |
2461 | return; | |
2462 | ||
dfd4cc63 | 2463 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2464 | { |
2465 | if (debug_linux_nat) | |
2466 | fprintf_unfiltered (gdb_stdlog, | |
2467 | "MCIS: Clearing bogus flag for %s\n", | |
2468 | target_pid_to_str (lp->ptid)); | |
2469 | lp->ignore_sigint = 0; | |
2470 | } | |
2471 | } | |
2472 | ||
ebec9a0f PA |
2473 | /* Fetch the possible triggered data watchpoint info and store it in |
2474 | LP. | |
2475 | ||
2476 | On some archs, like x86, that use debug registers to set | |
2477 | watchpoints, it's possible that the way to know which watched | |
2478 | address trapped, is to check the register that is used to select | |
2479 | which address to watch. Problem is, between setting the watchpoint | |
2480 | and reading back which data address trapped, the user may change | |
2481 | the set of watchpoints, and, as a consequence, GDB changes the | |
2482 | debug registers in the inferior. To avoid reading back a stale | |
2483 | stopped-data-address when that happens, we cache in LP the fact | |
2484 | that a watchpoint trapped, and the corresponding data address, as | |
2485 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2486 | registers meanwhile, we have the cached data we can rely on. */ | |
2487 | ||
2488 | static void | |
2489 | save_sigtrap (struct lwp_info *lp) | |
2490 | { | |
2491 | struct cleanup *old_chain; | |
2492 | ||
2493 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
2494 | { | |
2495 | lp->stopped_by_watchpoint = 0; | |
2496 | return; | |
2497 | } | |
2498 | ||
2499 | old_chain = save_inferior_ptid (); | |
2500 | inferior_ptid = lp->ptid; | |
2501 | ||
6a109b6b | 2502 | lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint (linux_ops); |
ebec9a0f PA |
2503 | |
2504 | if (lp->stopped_by_watchpoint) | |
2505 | { | |
2506 | if (linux_ops->to_stopped_data_address != NULL) | |
2507 | lp->stopped_data_address_p = | |
2508 | linux_ops->to_stopped_data_address (¤t_target, | |
2509 | &lp->stopped_data_address); | |
2510 | else | |
2511 | lp->stopped_data_address_p = 0; | |
2512 | } | |
2513 | ||
2514 | do_cleanups (old_chain); | |
2515 | } | |
2516 | ||
2517 | /* See save_sigtrap. */ | |
2518 | ||
2519 | static int | |
6a109b6b | 2520 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2521 | { |
2522 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2523 | ||
2524 | gdb_assert (lp != NULL); | |
2525 | ||
2526 | return lp->stopped_by_watchpoint; | |
2527 | } | |
2528 | ||
2529 | static int | |
2530 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2531 | { | |
2532 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2533 | ||
2534 | gdb_assert (lp != NULL); | |
2535 | ||
2536 | *addr_p = lp->stopped_data_address; | |
2537 | ||
2538 | return lp->stopped_data_address_p; | |
2539 | } | |
2540 | ||
26ab7092 JK |
2541 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2542 | ||
2543 | static int | |
2544 | sigtrap_is_event (int status) | |
2545 | { | |
2546 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2547 | } | |
2548 | ||
2549 | /* SIGTRAP-like events recognizer. */ | |
2550 | ||
2551 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
2552 | ||
00390b84 JK |
2553 | /* Check for SIGTRAP-like events in LP. */ |
2554 | ||
2555 | static int | |
2556 | linux_nat_lp_status_is_event (struct lwp_info *lp) | |
2557 | { | |
2558 | /* We check for lp->waitstatus in addition to lp->status, because we can | |
2559 | have pending process exits recorded in lp->status | |
2560 | and W_EXITCODE(0,0) == 0. We should probably have an additional | |
2561 | lp->status_p flag. */ | |
2562 | ||
2563 | return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE | |
2564 | && linux_nat_status_is_event (lp->status)); | |
2565 | } | |
2566 | ||
26ab7092 JK |
2567 | /* Set alternative SIGTRAP-like events recognizer. If |
2568 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2569 | applied. */ | |
2570 | ||
2571 | void | |
2572 | linux_nat_set_status_is_event (struct target_ops *t, | |
2573 | int (*status_is_event) (int status)) | |
2574 | { | |
2575 | linux_nat_status_is_event = status_is_event; | |
2576 | } | |
2577 | ||
57380f4e DJ |
2578 | /* Wait until LP is stopped. */ |
2579 | ||
2580 | static int | |
2581 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2582 | { | |
dfd4cc63 | 2583 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
6c95b8df PA |
2584 | |
2585 | /* If this is a vfork parent, bail out, it is not going to report | |
2586 | any SIGSTOP until the vfork is done with. */ | |
2587 | if (inf->vfork_child != NULL) | |
2588 | return 0; | |
2589 | ||
d6b0e80f AC |
2590 | if (!lp->stopped) |
2591 | { | |
2592 | int status; | |
2593 | ||
2594 | status = wait_lwp (lp); | |
2595 | if (status == 0) | |
2596 | return 0; | |
2597 | ||
57380f4e DJ |
2598 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2599 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2600 | { |
57380f4e | 2601 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2602 | |
2603 | errno = 0; | |
dfd4cc63 | 2604 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2605 | lp->stopped = 0; |
d6b0e80f AC |
2606 | if (debug_linux_nat) |
2607 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2608 | "PTRACE_CONT %s, 0, 0 (%s) " |
2609 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2610 | target_pid_to_str (lp->ptid), |
2611 | errno ? safe_strerror (errno) : "OK"); | |
2612 | ||
57380f4e | 2613 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2614 | } |
2615 | ||
57380f4e DJ |
2616 | maybe_clear_ignore_sigint (lp); |
2617 | ||
d6b0e80f AC |
2618 | if (WSTOPSIG (status) != SIGSTOP) |
2619 | { | |
e5ef252a | 2620 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2621 | |
e5ef252a PA |
2622 | save_sigtrap (lp); |
2623 | ||
2624 | if (debug_linux_nat) | |
2625 | fprintf_unfiltered (gdb_stdlog, | |
2626 | "SWC: Pending event %s in %s\n", | |
2627 | status_to_str ((int) status), | |
2628 | target_pid_to_str (lp->ptid)); | |
2629 | ||
2630 | /* Save the sigtrap event. */ | |
2631 | lp->status = status; | |
e5ef252a | 2632 | gdb_assert (lp->signalled); |
d6b0e80f AC |
2633 | } |
2634 | else | |
2635 | { | |
2636 | /* We caught the SIGSTOP that we intended to catch, so | |
2637 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2638 | |
2639 | if (debug_linux_nat) | |
2640 | fprintf_unfiltered (gdb_stdlog, | |
2641 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2642 | target_pid_to_str (lp->ptid)); | |
2643 | ||
e5ef252a PA |
2644 | /* Reset SIGNALLED only after the stop_wait_callback call |
2645 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2646 | lp->signalled = 0; |
2647 | } | |
2648 | } | |
2649 | ||
2650 | return 0; | |
2651 | } | |
2652 | ||
d6b0e80f AC |
2653 | /* Return non-zero if LP has a wait status pending. */ |
2654 | ||
2655 | static int | |
2656 | status_callback (struct lwp_info *lp, void *data) | |
2657 | { | |
2658 | /* Only report a pending wait status if we pretend that this has | |
2659 | indeed been resumed. */ | |
ca2163eb PA |
2660 | if (!lp->resumed) |
2661 | return 0; | |
2662 | ||
2663 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2664 | { | |
2665 | /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event, | |
766062f6 | 2666 | or a pending process exit. Note that `W_EXITCODE(0,0) == |
ca2163eb PA |
2667 | 0', so a clean process exit can not be stored pending in |
2668 | lp->status, it is indistinguishable from | |
2669 | no-pending-status. */ | |
2670 | return 1; | |
2671 | } | |
2672 | ||
2673 | if (lp->status != 0) | |
2674 | return 1; | |
2675 | ||
2676 | return 0; | |
d6b0e80f AC |
2677 | } |
2678 | ||
2679 | /* Return non-zero if LP isn't stopped. */ | |
2680 | ||
2681 | static int | |
2682 | running_callback (struct lwp_info *lp, void *data) | |
2683 | { | |
25289eb2 PA |
2684 | return (!lp->stopped |
2685 | || ((lp->status != 0 | |
2686 | || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2687 | && lp->resumed)); | |
d6b0e80f AC |
2688 | } |
2689 | ||
2690 | /* Count the LWP's that have had events. */ | |
2691 | ||
2692 | static int | |
2693 | count_events_callback (struct lwp_info *lp, void *data) | |
2694 | { | |
2695 | int *count = data; | |
2696 | ||
2697 | gdb_assert (count != NULL); | |
2698 | ||
e09490f1 | 2699 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2700 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2701 | (*count)++; |
2702 | ||
2703 | return 0; | |
2704 | } | |
2705 | ||
2706 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2707 | ||
2708 | static int | |
2709 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2710 | { | |
25289eb2 PA |
2711 | if (lp->last_resume_kind == resume_step |
2712 | && lp->status != 0) | |
d6b0e80f AC |
2713 | return 1; |
2714 | else | |
2715 | return 0; | |
2716 | } | |
2717 | ||
2718 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2719 | ||
2720 | static int | |
2721 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2722 | { | |
2723 | int *selector = data; | |
2724 | ||
2725 | gdb_assert (selector != NULL); | |
2726 | ||
1777feb0 | 2727 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2728 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2729 | if ((*selector)-- == 0) |
2730 | return 1; | |
2731 | ||
2732 | return 0; | |
2733 | } | |
2734 | ||
710151dd PA |
2735 | static int |
2736 | cancel_breakpoint (struct lwp_info *lp) | |
2737 | { | |
2738 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2739 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2740 | LWP. We will handle the current event, eventually we will resume | |
2741 | this LWP, and this breakpoint will trap again. | |
2742 | ||
2743 | If we do not do this, then we run the risk that the user will | |
2744 | delete or disable the breakpoint, but the LWP will have already | |
2745 | tripped on it. */ | |
2746 | ||
515630c5 UW |
2747 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2748 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2749 | CORE_ADDR pc; | |
2750 | ||
118e6252 | 2751 | pc = regcache_read_pc (regcache) - target_decr_pc_after_break (gdbarch); |
6c95b8df | 2752 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
710151dd PA |
2753 | { |
2754 | if (debug_linux_nat) | |
2755 | fprintf_unfiltered (gdb_stdlog, | |
2756 | "CB: Push back breakpoint for %s\n", | |
2757 | target_pid_to_str (lp->ptid)); | |
2758 | ||
2759 | /* Back up the PC if necessary. */ | |
118e6252 | 2760 | if (target_decr_pc_after_break (gdbarch)) |
515630c5 UW |
2761 | regcache_write_pc (regcache, pc); |
2762 | ||
710151dd PA |
2763 | return 1; |
2764 | } | |
2765 | return 0; | |
2766 | } | |
2767 | ||
d6b0e80f AC |
2768 | static int |
2769 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2770 | { | |
2771 | struct lwp_info *event_lp = data; | |
2772 | ||
2773 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2774 | if (lp == event_lp) | |
2775 | return 0; | |
2776 | ||
2777 | /* If a LWP other than the LWP that we're reporting an event for has | |
2778 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2779 | then just arrange for it to hit it again later. We don't keep | |
2780 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2781 | LWP. We will handle the current event, eventually we will resume | |
2782 | all LWPs, and this one will get its breakpoint trap again. | |
2783 | ||
2784 | If we do not do this, then we run the risk that the user will | |
2785 | delete or disable the breakpoint, but the LWP will have already | |
2786 | tripped on it. */ | |
2787 | ||
00390b84 | 2788 | if (linux_nat_lp_status_is_event (lp) |
710151dd PA |
2789 | && cancel_breakpoint (lp)) |
2790 | /* Throw away the SIGTRAP. */ | |
2791 | lp->status = 0; | |
d6b0e80f AC |
2792 | |
2793 | return 0; | |
2794 | } | |
2795 | ||
2796 | /* Select one LWP out of those that have events pending. */ | |
2797 | ||
2798 | static void | |
d90e17a7 | 2799 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2800 | { |
2801 | int num_events = 0; | |
2802 | int random_selector; | |
2803 | struct lwp_info *event_lp; | |
2804 | ||
ac264b3b | 2805 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2806 | (*orig_lp)->status = *status; |
2807 | ||
2808 | /* Give preference to any LWP that is being single-stepped. */ | |
d90e17a7 PA |
2809 | event_lp = iterate_over_lwps (filter, |
2810 | select_singlestep_lwp_callback, NULL); | |
d6b0e80f AC |
2811 | if (event_lp != NULL) |
2812 | { | |
2813 | if (debug_linux_nat) | |
2814 | fprintf_unfiltered (gdb_stdlog, | |
2815 | "SEL: Select single-step %s\n", | |
2816 | target_pid_to_str (event_lp->ptid)); | |
2817 | } | |
2818 | else | |
2819 | { | |
2820 | /* No single-stepping LWP. Select one at random, out of those | |
2821 | which have had SIGTRAP events. */ | |
2822 | ||
2823 | /* First see how many SIGTRAP events we have. */ | |
d90e17a7 | 2824 | iterate_over_lwps (filter, count_events_callback, &num_events); |
d6b0e80f AC |
2825 | |
2826 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2827 | random_selector = (int) | |
2828 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2829 | ||
2830 | if (debug_linux_nat && num_events > 1) | |
2831 | fprintf_unfiltered (gdb_stdlog, | |
2832 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2833 | num_events, random_selector); | |
2834 | ||
d90e17a7 PA |
2835 | event_lp = iterate_over_lwps (filter, |
2836 | select_event_lwp_callback, | |
d6b0e80f AC |
2837 | &random_selector); |
2838 | } | |
2839 | ||
2840 | if (event_lp != NULL) | |
2841 | { | |
2842 | /* Switch the event LWP. */ | |
2843 | *orig_lp = event_lp; | |
2844 | *status = event_lp->status; | |
2845 | } | |
2846 | ||
2847 | /* Flush the wait status for the event LWP. */ | |
2848 | (*orig_lp)->status = 0; | |
2849 | } | |
2850 | ||
2851 | /* Return non-zero if LP has been resumed. */ | |
2852 | ||
2853 | static int | |
2854 | resumed_callback (struct lwp_info *lp, void *data) | |
2855 | { | |
2856 | return lp->resumed; | |
2857 | } | |
2858 | ||
12d9289a PA |
2859 | /* Stop an active thread, verify it still exists, then resume it. If |
2860 | the thread ends up with a pending status, then it is not resumed, | |
2861 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2862 | |
2863 | static int | |
2864 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2865 | { | |
12d9289a PA |
2866 | int *new_pending_p = data; |
2867 | ||
25289eb2 | 2868 | if (!lp->stopped) |
d6b0e80f | 2869 | { |
25289eb2 PA |
2870 | ptid_t ptid = lp->ptid; |
2871 | ||
d6b0e80f AC |
2872 | stop_callback (lp, NULL); |
2873 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2874 | |
2875 | /* Resume if the lwp still exists, and the core wanted it | |
2876 | running. */ | |
12d9289a PA |
2877 | lp = find_lwp_pid (ptid); |
2878 | if (lp != NULL) | |
25289eb2 | 2879 | { |
12d9289a PA |
2880 | if (lp->last_resume_kind == resume_stop |
2881 | && lp->status == 0) | |
2882 | { | |
2883 | /* The core wanted the LWP to stop. Even if it stopped | |
2884 | cleanly (with SIGSTOP), leave the event pending. */ | |
2885 | if (debug_linux_nat) | |
2886 | fprintf_unfiltered (gdb_stdlog, | |
2887 | "SARC: core wanted LWP %ld stopped " | |
2888 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2889 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2890 | lp->status = W_STOPCODE (SIGSTOP); |
2891 | } | |
2892 | ||
2893 | if (lp->status == 0) | |
2894 | { | |
2895 | if (debug_linux_nat) | |
2896 | fprintf_unfiltered (gdb_stdlog, | |
2897 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2898 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2899 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2900 | } |
2901 | else | |
2902 | { | |
2903 | if (debug_linux_nat) | |
2904 | fprintf_unfiltered (gdb_stdlog, | |
2905 | "SARC: not re-resuming LWP %ld " | |
2906 | "(has pending)\n", | |
dfd4cc63 | 2907 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2908 | if (new_pending_p) |
2909 | *new_pending_p = 1; | |
2910 | } | |
25289eb2 | 2911 | } |
d6b0e80f AC |
2912 | } |
2913 | return 0; | |
2914 | } | |
2915 | ||
02f3fc28 | 2916 | /* Check if we should go on and pass this event to common code. |
12d9289a PA |
2917 | Return the affected lwp if we are, or NULL otherwise. If we stop |
2918 | all lwps temporarily, we may end up with new pending events in some | |
2919 | other lwp. In that case set *NEW_PENDING_P to true. */ | |
2920 | ||
02f3fc28 | 2921 | static struct lwp_info * |
0e5bf2a8 | 2922 | linux_nat_filter_event (int lwpid, int status, int *new_pending_p) |
02f3fc28 PA |
2923 | { |
2924 | struct lwp_info *lp; | |
2925 | ||
12d9289a PA |
2926 | *new_pending_p = 0; |
2927 | ||
02f3fc28 PA |
2928 | lp = find_lwp_pid (pid_to_ptid (lwpid)); |
2929 | ||
2930 | /* Check for stop events reported by a process we didn't already | |
2931 | know about - anything not already in our LWP list. | |
2932 | ||
2933 | If we're expecting to receive stopped processes after | |
2934 | fork, vfork, and clone events, then we'll just add the | |
2935 | new one to our list and go back to waiting for the event | |
2936 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2937 | from waitpid before or after the event is. |
2938 | ||
2939 | But note the case of a non-leader thread exec'ing after the | |
2940 | leader having exited, and gone from our lists. The non-leader | |
2941 | thread changes its tid to the tgid. */ | |
2942 | ||
2943 | if (WIFSTOPPED (status) && lp == NULL | |
2944 | && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC)) | |
2945 | { | |
2946 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2947 | if (debug_linux_nat) | |
2948 | fprintf_unfiltered (gdb_stdlog, | |
2949 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2950 | lwpid); | |
2951 | ||
dfd4cc63 | 2952 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2953 | lp->stopped = 1; |
2954 | lp->resumed = 1; | |
2955 | add_thread (lp->ptid); | |
2956 | } | |
2957 | ||
02f3fc28 PA |
2958 | if (WIFSTOPPED (status) && !lp) |
2959 | { | |
84636d28 | 2960 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2961 | return NULL; |
2962 | } | |
2963 | ||
2964 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2965 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2966 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2967 | exits. */ |
2968 | if (!WIFSTOPPED (status) && !lp) | |
2969 | return NULL; | |
2970 | ||
8817a6f2 PA |
2971 | /* This LWP is stopped now. (And if dead, this prevents it from |
2972 | ever being continued.) */ | |
2973 | lp->stopped = 1; | |
2974 | ||
ca2163eb PA |
2975 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2976 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2977 | { | |
2978 | /* No longer need the sysgood bit. The ptrace event ends up | |
2979 | recorded in lp->waitstatus if we care for it. We can carry | |
2980 | on handling the event like a regular SIGTRAP from here | |
2981 | on. */ | |
2982 | status = W_STOPCODE (SIGTRAP); | |
2983 | if (linux_handle_syscall_trap (lp, 0)) | |
2984 | return NULL; | |
2985 | } | |
02f3fc28 | 2986 | |
ca2163eb PA |
2987 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2988 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
02f3fc28 PA |
2989 | { |
2990 | if (debug_linux_nat) | |
2991 | fprintf_unfiltered (gdb_stdlog, | |
2992 | "LLW: Handling extended status 0x%06x\n", | |
2993 | status); | |
2994 | if (linux_handle_extended_wait (lp, status, 0)) | |
2995 | return NULL; | |
2996 | } | |
2997 | ||
26ab7092 | 2998 | if (linux_nat_status_is_event (status)) |
da559b09 | 2999 | save_sigtrap (lp); |
ca2163eb | 3000 | |
02f3fc28 | 3001 | /* Check if the thread has exited. */ |
d90e17a7 | 3002 | if ((WIFEXITED (status) || WIFSIGNALED (status)) |
dfd4cc63 | 3003 | && num_lwps (ptid_get_pid (lp->ptid)) > 1) |
02f3fc28 | 3004 | { |
9db03742 JB |
3005 | /* If this is the main thread, we must stop all threads and verify |
3006 | if they are still alive. This is because in the nptl thread model | |
3007 | on Linux 2.4, there is no signal issued for exiting LWPs | |
02f3fc28 PA |
3008 | other than the main thread. We only get the main thread exit |
3009 | signal once all child threads have already exited. If we | |
3010 | stop all the threads and use the stop_wait_callback to check | |
3011 | if they have exited we can determine whether this signal | |
3012 | should be ignored or whether it means the end of the debugged | |
3013 | application, regardless of which threading model is being | |
5d3b6af6 | 3014 | used. */ |
dfd4cc63 | 3015 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
02f3fc28 | 3016 | { |
dfd4cc63 | 3017 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), |
12d9289a | 3018 | stop_and_resume_callback, new_pending_p); |
02f3fc28 PA |
3019 | } |
3020 | ||
3021 | if (debug_linux_nat) | |
3022 | fprintf_unfiltered (gdb_stdlog, | |
3023 | "LLW: %s exited.\n", | |
3024 | target_pid_to_str (lp->ptid)); | |
3025 | ||
dfd4cc63 | 3026 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) |
9db03742 JB |
3027 | { |
3028 | /* If there is at least one more LWP, then the exit signal | |
3029 | was not the end of the debugged application and should be | |
3030 | ignored. */ | |
3031 | exit_lwp (lp); | |
3032 | return NULL; | |
3033 | } | |
02f3fc28 PA |
3034 | } |
3035 | ||
3036 | /* Check if the current LWP has previously exited. In the nptl | |
3037 | thread model, LWPs other than the main thread do not issue | |
3038 | signals when they exit so we must check whenever the thread has | |
3039 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3040 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3041 | { |
dfd4cc63 | 3042 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3043 | |
02f3fc28 PA |
3044 | if (debug_linux_nat) |
3045 | fprintf_unfiltered (gdb_stdlog, | |
3046 | "LLW: %s exited.\n", | |
3047 | target_pid_to_str (lp->ptid)); | |
3048 | ||
3049 | exit_lwp (lp); | |
3050 | ||
3051 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3052 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3053 | |
3054 | /* Discard the event. */ | |
3055 | return NULL; | |
3056 | } | |
3057 | ||
3058 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3059 | an attempt to stop an LWP. */ | |
3060 | if (lp->signalled | |
3061 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3062 | { | |
3063 | if (debug_linux_nat) | |
3064 | fprintf_unfiltered (gdb_stdlog, | |
3065 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3066 | target_pid_to_str (lp->ptid)); | |
3067 | ||
02f3fc28 PA |
3068 | lp->signalled = 0; |
3069 | ||
25289eb2 PA |
3070 | if (lp->last_resume_kind != resume_stop) |
3071 | { | |
3072 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3073 | |
25289eb2 PA |
3074 | registers_changed (); |
3075 | ||
7b50312a PA |
3076 | if (linux_nat_prepare_to_resume != NULL) |
3077 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3078 | linux_ops->to_resume (linux_ops, |
3079 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
3080 | lp->step, GDB_SIGNAL_0); | |
25289eb2 PA |
3081 | if (debug_linux_nat) |
3082 | fprintf_unfiltered (gdb_stdlog, | |
3083 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3084 | lp->step ? | |
3085 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3086 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3087 | |
25289eb2 PA |
3088 | lp->stopped = 0; |
3089 | gdb_assert (lp->resumed); | |
02f3fc28 | 3090 | |
25289eb2 PA |
3091 | /* Discard the event. */ |
3092 | return NULL; | |
3093 | } | |
02f3fc28 PA |
3094 | } |
3095 | ||
57380f4e DJ |
3096 | /* Make sure we don't report a SIGINT that we have already displayed |
3097 | for another thread. */ | |
3098 | if (lp->ignore_sigint | |
3099 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3100 | { | |
3101 | if (debug_linux_nat) | |
3102 | fprintf_unfiltered (gdb_stdlog, | |
3103 | "LLW: Delayed SIGINT caught for %s.\n", | |
3104 | target_pid_to_str (lp->ptid)); | |
3105 | ||
3106 | /* This is a delayed SIGINT. */ | |
3107 | lp->ignore_sigint = 0; | |
3108 | ||
3109 | registers_changed (); | |
7b50312a PA |
3110 | if (linux_nat_prepare_to_resume != NULL) |
3111 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3112 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3113 | lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3114 | if (debug_linux_nat) |
3115 | fprintf_unfiltered (gdb_stdlog, | |
3116 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3117 | lp->step ? | |
3118 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3119 | target_pid_to_str (lp->ptid)); | |
3120 | ||
3121 | lp->stopped = 0; | |
3122 | gdb_assert (lp->resumed); | |
3123 | ||
3124 | /* Discard the event. */ | |
3125 | return NULL; | |
3126 | } | |
3127 | ||
02f3fc28 PA |
3128 | /* An interesting event. */ |
3129 | gdb_assert (lp); | |
ca2163eb | 3130 | lp->status = status; |
02f3fc28 PA |
3131 | return lp; |
3132 | } | |
3133 | ||
0e5bf2a8 PA |
3134 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3135 | their exits until all other threads in the group have exited. */ | |
3136 | ||
3137 | static void | |
3138 | check_zombie_leaders (void) | |
3139 | { | |
3140 | struct inferior *inf; | |
3141 | ||
3142 | ALL_INFERIORS (inf) | |
3143 | { | |
3144 | struct lwp_info *leader_lp; | |
3145 | ||
3146 | if (inf->pid == 0) | |
3147 | continue; | |
3148 | ||
3149 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3150 | if (leader_lp != NULL | |
3151 | /* Check if there are other threads in the group, as we may | |
3152 | have raced with the inferior simply exiting. */ | |
3153 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3154 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3155 | { |
3156 | if (debug_linux_nat) | |
3157 | fprintf_unfiltered (gdb_stdlog, | |
3158 | "CZL: Thread group leader %d zombie " | |
3159 | "(it exited, or another thread execd).\n", | |
3160 | inf->pid); | |
3161 | ||
3162 | /* A leader zombie can mean one of two things: | |
3163 | ||
3164 | - It exited, and there's an exit status pending | |
3165 | available, or only the leader exited (not the whole | |
3166 | program). In the latter case, we can't waitpid the | |
3167 | leader's exit status until all other threads are gone. | |
3168 | ||
3169 | - There are 3 or more threads in the group, and a thread | |
3170 | other than the leader exec'd. On an exec, the Linux | |
3171 | kernel destroys all other threads (except the execing | |
3172 | one) in the thread group, and resets the execing thread's | |
3173 | tid to the tgid. No exit notification is sent for the | |
3174 | execing thread -- from the ptracer's perspective, it | |
3175 | appears as though the execing thread just vanishes. | |
3176 | Until we reap all other threads except the leader and the | |
3177 | execing thread, the leader will be zombie, and the | |
3178 | execing thread will be in `D (disc sleep)'. As soon as | |
3179 | all other threads are reaped, the execing thread changes | |
3180 | it's tid to the tgid, and the previous (zombie) leader | |
3181 | vanishes, giving place to the "new" leader. We could try | |
3182 | distinguishing the exit and exec cases, by waiting once | |
3183 | more, and seeing if something comes out, but it doesn't | |
3184 | sound useful. The previous leader _does_ go away, and | |
3185 | we'll re-add the new one once we see the exec event | |
3186 | (which is just the same as what would happen if the | |
3187 | previous leader did exit voluntarily before some other | |
3188 | thread execs). */ | |
3189 | ||
3190 | if (debug_linux_nat) | |
3191 | fprintf_unfiltered (gdb_stdlog, | |
3192 | "CZL: Thread group leader %d vanished.\n", | |
3193 | inf->pid); | |
3194 | exit_lwp (leader_lp); | |
3195 | } | |
3196 | } | |
3197 | } | |
3198 | ||
d6b0e80f | 3199 | static ptid_t |
7feb7d06 | 3200 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3201 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3202 | int target_options) | |
d6b0e80f | 3203 | { |
7feb7d06 | 3204 | static sigset_t prev_mask; |
4b60df3d | 3205 | enum resume_kind last_resume_kind; |
12d9289a | 3206 | struct lwp_info *lp; |
12d9289a | 3207 | int status; |
d6b0e80f | 3208 | |
01124a23 | 3209 | if (debug_linux_nat) |
b84876c2 PA |
3210 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3211 | ||
f973ed9c DJ |
3212 | /* The first time we get here after starting a new inferior, we may |
3213 | not have added it to the LWP list yet - this is the earliest | |
3214 | moment at which we know its PID. */ | |
d90e17a7 | 3215 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3216 | { |
27c9d204 PA |
3217 | /* Upgrade the main thread's ptid. */ |
3218 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3219 | ptid_build (ptid_get_pid (inferior_ptid), |
3220 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3221 | |
26cb8b7c | 3222 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3223 | lp->resumed = 1; |
3224 | } | |
3225 | ||
12696c10 | 3226 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3227 | block_child_signals (&prev_mask); |
d6b0e80f AC |
3228 | |
3229 | retry: | |
d90e17a7 PA |
3230 | lp = NULL; |
3231 | status = 0; | |
d6b0e80f AC |
3232 | |
3233 | /* First check if there is a LWP with a wait status pending. */ | |
0e5bf2a8 | 3234 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d6b0e80f | 3235 | { |
0e5bf2a8 | 3236 | /* Any LWP in the PTID group that's been resumed will do. */ |
d90e17a7 | 3237 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
d6b0e80f AC |
3238 | if (lp) |
3239 | { | |
ca2163eb | 3240 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3241 | fprintf_unfiltered (gdb_stdlog, |
3242 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3243 | status_to_str (lp->status), |
d6b0e80f AC |
3244 | target_pid_to_str (lp->ptid)); |
3245 | } | |
d6b0e80f | 3246 | } |
dfd4cc63 | 3247 | else if (ptid_lwp_p (ptid)) |
d6b0e80f AC |
3248 | { |
3249 | if (debug_linux_nat) | |
3250 | fprintf_unfiltered (gdb_stdlog, | |
3251 | "LLW: Waiting for specific LWP %s.\n", | |
3252 | target_pid_to_str (ptid)); | |
3253 | ||
3254 | /* We have a specific LWP to check. */ | |
3255 | lp = find_lwp_pid (ptid); | |
3256 | gdb_assert (lp); | |
d6b0e80f | 3257 | |
ca2163eb | 3258 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3259 | fprintf_unfiltered (gdb_stdlog, |
3260 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3261 | status_to_str (lp->status), |
d6b0e80f AC |
3262 | target_pid_to_str (lp->ptid)); |
3263 | ||
d90e17a7 PA |
3264 | /* We check for lp->waitstatus in addition to lp->status, |
3265 | because we can have pending process exits recorded in | |
3266 | lp->status and W_EXITCODE(0,0) == 0. We should probably have | |
3267 | an additional lp->status_p flag. */ | |
ca2163eb | 3268 | if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) |
d90e17a7 | 3269 | lp = NULL; |
d6b0e80f AC |
3270 | } |
3271 | ||
b84876c2 PA |
3272 | if (!target_can_async_p ()) |
3273 | { | |
3274 | /* Causes SIGINT to be passed on to the attached process. */ | |
3275 | set_sigint_trap (); | |
b84876c2 | 3276 | } |
d6b0e80f | 3277 | |
0e5bf2a8 | 3278 | /* But if we don't find a pending event, we'll have to wait. */ |
7feb7d06 | 3279 | |
d90e17a7 | 3280 | while (lp == NULL) |
d6b0e80f AC |
3281 | { |
3282 | pid_t lwpid; | |
3283 | ||
0e5bf2a8 PA |
3284 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3285 | quirks: | |
3286 | ||
3287 | - If the thread group leader exits while other threads in the | |
3288 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3289 | waitpid won't return an exit status until the other threads | |
3290 | in the group are reapped. | |
3291 | ||
3292 | - When a non-leader thread execs, that thread just vanishes | |
3293 | without reporting an exit (so we'd hang if we waited for it | |
3294 | explicitly in that case). The exec event is reported to | |
3295 | the TGID pid. */ | |
3296 | ||
3297 | errno = 0; | |
3298 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3299 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3300 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3301 | ||
3302 | if (debug_linux_nat) | |
3303 | fprintf_unfiltered (gdb_stdlog, | |
3304 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3305 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3306 | |
d6b0e80f AC |
3307 | if (lwpid > 0) |
3308 | { | |
12d9289a PA |
3309 | /* If this is true, then we paused LWPs momentarily, and may |
3310 | now have pending events to handle. */ | |
3311 | int new_pending; | |
3312 | ||
d6b0e80f AC |
3313 | if (debug_linux_nat) |
3314 | { | |
3315 | fprintf_unfiltered (gdb_stdlog, | |
3316 | "LLW: waitpid %ld received %s\n", | |
3317 | (long) lwpid, status_to_str (status)); | |
3318 | } | |
3319 | ||
0e5bf2a8 | 3320 | lp = linux_nat_filter_event (lwpid, status, &new_pending); |
d90e17a7 | 3321 | |
33355866 JK |
3322 | /* STATUS is now no longer valid, use LP->STATUS instead. */ |
3323 | status = 0; | |
3324 | ||
0e5bf2a8 | 3325 | if (lp && !ptid_match (lp->ptid, ptid)) |
d6b0e80f | 3326 | { |
e3e9f5a2 PA |
3327 | gdb_assert (lp->resumed); |
3328 | ||
d90e17a7 | 3329 | if (debug_linux_nat) |
3e43a32a MS |
3330 | fprintf (stderr, |
3331 | "LWP %ld got an event %06x, leaving pending.\n", | |
33355866 | 3332 | ptid_get_lwp (lp->ptid), lp->status); |
d90e17a7 | 3333 | |
ca2163eb | 3334 | if (WIFSTOPPED (lp->status)) |
d90e17a7 | 3335 | { |
ca2163eb | 3336 | if (WSTOPSIG (lp->status) != SIGSTOP) |
d90e17a7 | 3337 | { |
e3e9f5a2 PA |
3338 | /* Cancel breakpoint hits. The breakpoint may |
3339 | be removed before we fetch events from this | |
3340 | process to report to the core. It is best | |
3341 | not to assume the moribund breakpoints | |
3342 | heuristic always handles these cases --- it | |
3343 | could be too many events go through to the | |
3344 | core before this one is handled. All-stop | |
3345 | always cancels breakpoint hits in all | |
3346 | threads. */ | |
3347 | if (non_stop | |
00390b84 | 3348 | && linux_nat_lp_status_is_event (lp) |
e3e9f5a2 PA |
3349 | && cancel_breakpoint (lp)) |
3350 | { | |
3351 | /* Throw away the SIGTRAP. */ | |
3352 | lp->status = 0; | |
3353 | ||
3354 | if (debug_linux_nat) | |
3355 | fprintf (stderr, | |
3e43a32a MS |
3356 | "LLW: LWP %ld hit a breakpoint while" |
3357 | " waiting for another process;" | |
3358 | " cancelled it\n", | |
e3e9f5a2 PA |
3359 | ptid_get_lwp (lp->ptid)); |
3360 | } | |
d90e17a7 PA |
3361 | } |
3362 | else | |
8817a6f2 | 3363 | lp->signalled = 0; |
d90e17a7 | 3364 | } |
33355866 | 3365 | else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status)) |
d90e17a7 PA |
3366 | { |
3367 | if (debug_linux_nat) | |
3e43a32a MS |
3368 | fprintf (stderr, |
3369 | "Process %ld exited while stopping LWPs\n", | |
d90e17a7 PA |
3370 | ptid_get_lwp (lp->ptid)); |
3371 | ||
3372 | /* This was the last lwp in the process. Since | |
3373 | events are serialized to GDB core, and we can't | |
3374 | report this one right now, but GDB core and the | |
3375 | other target layers will want to be notified | |
3376 | about the exit code/signal, leave the status | |
3377 | pending for the next time we're able to report | |
3378 | it. */ | |
d90e17a7 | 3379 | |
d90e17a7 PA |
3380 | /* Dead LWP's aren't expected to reported a pending |
3381 | sigstop. */ | |
3382 | lp->signalled = 0; | |
3383 | ||
3384 | /* Store the pending event in the waitstatus as | |
3385 | well, because W_EXITCODE(0,0) == 0. */ | |
ca2163eb | 3386 | store_waitstatus (&lp->waitstatus, lp->status); |
d90e17a7 PA |
3387 | } |
3388 | ||
3389 | /* Keep looking. */ | |
3390 | lp = NULL; | |
d6b0e80f AC |
3391 | } |
3392 | ||
0e5bf2a8 | 3393 | if (new_pending) |
d90e17a7 | 3394 | { |
0e5bf2a8 PA |
3395 | /* Some LWP now has a pending event. Go all the way |
3396 | back to check it. */ | |
3397 | goto retry; | |
3398 | } | |
12d9289a | 3399 | |
0e5bf2a8 PA |
3400 | if (lp) |
3401 | { | |
3402 | /* We got an event to report to the core. */ | |
3403 | break; | |
d90e17a7 | 3404 | } |
0e5bf2a8 PA |
3405 | |
3406 | /* Retry until nothing comes out of waitpid. A single | |
3407 | SIGCHLD can indicate more than one child stopped. */ | |
3408 | continue; | |
d6b0e80f AC |
3409 | } |
3410 | ||
0e5bf2a8 PA |
3411 | /* Check for zombie thread group leaders. Those can't be reaped |
3412 | until all other threads in the thread group are. */ | |
3413 | check_zombie_leaders (); | |
d6b0e80f | 3414 | |
0e5bf2a8 PA |
3415 | /* If there are no resumed children left, bail. We'd be stuck |
3416 | forever in the sigsuspend call below otherwise. */ | |
3417 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3418 | { | |
3419 | if (debug_linux_nat) | |
3420 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3421 | |
0e5bf2a8 | 3422 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3423 | |
0e5bf2a8 PA |
3424 | if (!target_can_async_p ()) |
3425 | clear_sigint_trap (); | |
b84876c2 | 3426 | |
0e5bf2a8 PA |
3427 | restore_child_signals_mask (&prev_mask); |
3428 | return minus_one_ptid; | |
d6b0e80f | 3429 | } |
28736962 | 3430 | |
0e5bf2a8 PA |
3431 | /* No interesting event to report to the core. */ |
3432 | ||
3433 | if (target_options & TARGET_WNOHANG) | |
3434 | { | |
01124a23 | 3435 | if (debug_linux_nat) |
28736962 PA |
3436 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3437 | ||
0e5bf2a8 | 3438 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3439 | restore_child_signals_mask (&prev_mask); |
3440 | return minus_one_ptid; | |
3441 | } | |
d6b0e80f AC |
3442 | |
3443 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3444 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3445 | |
3446 | /* Block until we get an event reported with SIGCHLD. */ | |
3447 | sigsuspend (&suspend_mask); | |
d6b0e80f AC |
3448 | } |
3449 | ||
b84876c2 | 3450 | if (!target_can_async_p ()) |
d26b5354 | 3451 | clear_sigint_trap (); |
d6b0e80f AC |
3452 | |
3453 | gdb_assert (lp); | |
3454 | ||
ca2163eb PA |
3455 | status = lp->status; |
3456 | lp->status = 0; | |
3457 | ||
d6b0e80f AC |
3458 | /* Don't report signals that GDB isn't interested in, such as |
3459 | signals that are neither printed nor stopped upon. Stopping all | |
3460 | threads can be a bit time-consuming so if we want decent | |
3461 | performance with heavily multi-threaded programs, especially when | |
3462 | they're using a high frequency timer, we'd better avoid it if we | |
3463 | can. */ | |
3464 | ||
3465 | if (WIFSTOPPED (status)) | |
3466 | { | |
2ea28649 | 3467 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); |
d6b0e80f | 3468 | |
2455069d UW |
3469 | /* When using hardware single-step, we need to report every signal. |
3470 | Otherwise, signals in pass_mask may be short-circuited. */ | |
d539ed7e | 3471 | if (!lp->step |
2455069d | 3472 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))) |
d6b0e80f AC |
3473 | { |
3474 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
3475 | here? It is not clear we should. GDB may not expect | |
3476 | other threads to run. On the other hand, not resuming | |
3477 | newly attached threads may cause an unwanted delay in | |
3478 | getting them running. */ | |
3479 | registers_changed (); | |
7b50312a PA |
3480 | if (linux_nat_prepare_to_resume != NULL) |
3481 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3482 | linux_ops->to_resume (linux_ops, |
3483 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
10d6c8cd | 3484 | lp->step, signo); |
d6b0e80f AC |
3485 | if (debug_linux_nat) |
3486 | fprintf_unfiltered (gdb_stdlog, | |
3487 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3488 | lp->step ? | |
3489 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3490 | target_pid_to_str (lp->ptid), | |
a493e3e2 | 3491 | (signo != GDB_SIGNAL_0 |
2ea28649 | 3492 | ? strsignal (gdb_signal_to_host (signo)) |
423ec54c | 3493 | : "0")); |
d6b0e80f | 3494 | lp->stopped = 0; |
d6b0e80f AC |
3495 | goto retry; |
3496 | } | |
3497 | ||
1ad15515 | 3498 | if (!non_stop) |
d6b0e80f | 3499 | { |
1ad15515 PA |
3500 | /* Only do the below in all-stop, as we currently use SIGINT |
3501 | to implement target_stop (see linux_nat_stop) in | |
3502 | non-stop. */ | |
a493e3e2 | 3503 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) |
1ad15515 PA |
3504 | { |
3505 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3506 | forwarded to the entire process group, that is, all LWPs | |
3507 | will receive it - unless they're using CLONE_THREAD to | |
3508 | share signals. Since we only want to report it once, we | |
3509 | mark it as ignored for all LWPs except this one. */ | |
d90e17a7 PA |
3510 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)), |
3511 | set_ignore_sigint, NULL); | |
1ad15515 PA |
3512 | lp->ignore_sigint = 0; |
3513 | } | |
3514 | else | |
3515 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
3516 | } |
3517 | } | |
3518 | ||
3519 | /* This LWP is stopped now. */ | |
3520 | lp->stopped = 1; | |
3521 | ||
3522 | if (debug_linux_nat) | |
3523 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
3524 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
3525 | ||
4c28f408 PA |
3526 | if (!non_stop) |
3527 | { | |
3528 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3529 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3530 | |
3531 | /* ... and wait until all of them have reported back that | |
3532 | they're no longer running. */ | |
d90e17a7 | 3533 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
4c28f408 PA |
3534 | |
3535 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3536 | from among those that have had events. Giving equal priority | |
3537 | to all LWPs that have had events helps prevent | |
3538 | starvation. */ | |
0e5bf2a8 | 3539 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d90e17a7 | 3540 | select_event_lwp (ptid, &lp, &status); |
d6b0e80f | 3541 | |
e3e9f5a2 PA |
3542 | /* Now that we've selected our final event LWP, cancel any |
3543 | breakpoints in other LWPs that have hit a GDB breakpoint. | |
3544 | See the comment in cancel_breakpoints_callback to find out | |
3545 | why. */ | |
3546 | iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp); | |
3547 | ||
4b60df3d PA |
3548 | /* We'll need this to determine whether to report a SIGSTOP as |
3549 | TARGET_WAITKIND_0. Need to take a copy because | |
3550 | resume_clear_callback clears it. */ | |
3551 | last_resume_kind = lp->last_resume_kind; | |
3552 | ||
e3e9f5a2 PA |
3553 | /* In all-stop, from the core's perspective, all LWPs are now |
3554 | stopped until a new resume action is sent over. */ | |
3555 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3556 | } | |
3557 | else | |
25289eb2 | 3558 | { |
4b60df3d PA |
3559 | /* See above. */ |
3560 | last_resume_kind = lp->last_resume_kind; | |
3561 | resume_clear_callback (lp, NULL); | |
25289eb2 | 3562 | } |
d6b0e80f | 3563 | |
26ab7092 | 3564 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3565 | { |
d6b0e80f AC |
3566 | if (debug_linux_nat) |
3567 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3568 | "LLW: trap ptid is %s.\n", |
3569 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3570 | } |
d6b0e80f AC |
3571 | |
3572 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3573 | { | |
3574 | *ourstatus = lp->waitstatus; | |
3575 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3576 | } | |
3577 | else | |
3578 | store_waitstatus (ourstatus, status); | |
3579 | ||
01124a23 | 3580 | if (debug_linux_nat) |
b84876c2 PA |
3581 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3582 | ||
7feb7d06 | 3583 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3584 | |
4b60df3d | 3585 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3586 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3587 | && WSTOPSIG (status) == SIGSTOP) | |
3588 | { | |
3589 | /* A thread that has been requested to stop by GDB with | |
3590 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3591 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3592 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3593 | } |
3594 | ||
1e225492 JK |
3595 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3596 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3597 | lp->core = -1; | |
3598 | else | |
2e794194 | 3599 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3600 | |
f973ed9c | 3601 | return lp->ptid; |
d6b0e80f AC |
3602 | } |
3603 | ||
e3e9f5a2 PA |
3604 | /* Resume LWPs that are currently stopped without any pending status |
3605 | to report, but are resumed from the core's perspective. */ | |
3606 | ||
3607 | static int | |
3608 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3609 | { | |
3610 | ptid_t *wait_ptid_p = data; | |
3611 | ||
3612 | if (lp->stopped | |
3613 | && lp->resumed | |
3614 | && lp->status == 0 | |
3615 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
3616 | { | |
336060f3 PA |
3617 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3618 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
3619 | CORE_ADDR pc = regcache_read_pc (regcache); | |
3620 | ||
e3e9f5a2 PA |
3621 | gdb_assert (is_executing (lp->ptid)); |
3622 | ||
3623 | /* Don't bother if there's a breakpoint at PC that we'd hit | |
3624 | immediately, and we're not waiting for this LWP. */ | |
3625 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3626 | { | |
e3e9f5a2 PA |
3627 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
3628 | return 0; | |
3629 | } | |
3630 | ||
3631 | if (debug_linux_nat) | |
3632 | fprintf_unfiltered (gdb_stdlog, | |
336060f3 PA |
3633 | "RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", |
3634 | target_pid_to_str (lp->ptid), | |
3635 | paddress (gdbarch, pc), | |
3636 | lp->step); | |
e3e9f5a2 | 3637 | |
336060f3 | 3638 | registers_changed (); |
7b50312a PA |
3639 | if (linux_nat_prepare_to_resume != NULL) |
3640 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3641 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3642 | lp->step, GDB_SIGNAL_0); |
e3e9f5a2 | 3643 | lp->stopped = 0; |
e3e9f5a2 PA |
3644 | lp->stopped_by_watchpoint = 0; |
3645 | } | |
3646 | ||
3647 | return 0; | |
3648 | } | |
3649 | ||
7feb7d06 PA |
3650 | static ptid_t |
3651 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3652 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3653 | int target_options) | |
7feb7d06 PA |
3654 | { |
3655 | ptid_t event_ptid; | |
3656 | ||
3657 | if (debug_linux_nat) | |
09826ec5 PA |
3658 | { |
3659 | char *options_string; | |
3660 | ||
3661 | options_string = target_options_to_string (target_options); | |
3662 | fprintf_unfiltered (gdb_stdlog, | |
3663 | "linux_nat_wait: [%s], [%s]\n", | |
3664 | target_pid_to_str (ptid), | |
3665 | options_string); | |
3666 | xfree (options_string); | |
3667 | } | |
7feb7d06 PA |
3668 | |
3669 | /* Flush the async file first. */ | |
3670 | if (target_can_async_p ()) | |
3671 | async_file_flush (); | |
3672 | ||
e3e9f5a2 PA |
3673 | /* Resume LWPs that are currently stopped without any pending status |
3674 | to report, but are resumed from the core's perspective. LWPs get | |
3675 | in this state if we find them stopping at a time we're not | |
3676 | interested in reporting the event (target_wait on a | |
3677 | specific_process, for example, see linux_nat_wait_1), and | |
3678 | meanwhile the event became uninteresting. Don't bother resuming | |
3679 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3680 | if (non_stop) | |
3681 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3682 | ||
47608cb1 | 3683 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3684 | |
3685 | /* If we requested any event, and something came out, assume there | |
3686 | may be more. If we requested a specific lwp or process, also | |
3687 | assume there may be more. */ | |
3688 | if (target_can_async_p () | |
6953d224 PA |
3689 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3690 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3691 | || !ptid_equal (ptid, minus_one_ptid))) |
3692 | async_file_mark (); | |
3693 | ||
3694 | /* Get ready for the next event. */ | |
3695 | if (target_can_async_p ()) | |
3696 | target_async (inferior_event_handler, 0); | |
3697 | ||
3698 | return event_ptid; | |
3699 | } | |
3700 | ||
d6b0e80f AC |
3701 | static int |
3702 | kill_callback (struct lwp_info *lp, void *data) | |
3703 | { | |
ed731959 JK |
3704 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3705 | ||
3706 | errno = 0; | |
dfd4cc63 | 3707 | kill (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 JK |
3708 | if (debug_linux_nat) |
3709 | fprintf_unfiltered (gdb_stdlog, | |
3710 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3711 | target_pid_to_str (lp->ptid), | |
3712 | errno ? safe_strerror (errno) : "OK"); | |
3713 | ||
3714 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3715 | ||
d6b0e80f | 3716 | errno = 0; |
dfd4cc63 | 3717 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f AC |
3718 | if (debug_linux_nat) |
3719 | fprintf_unfiltered (gdb_stdlog, | |
3720 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3721 | target_pid_to_str (lp->ptid), | |
3722 | errno ? safe_strerror (errno) : "OK"); | |
3723 | ||
3724 | return 0; | |
3725 | } | |
3726 | ||
3727 | static int | |
3728 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3729 | { | |
3730 | pid_t pid; | |
3731 | ||
3732 | /* We must make sure that there are no pending events (delayed | |
3733 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3734 | program doesn't interfere with any following debugging session. */ | |
3735 | ||
3736 | /* For cloned processes we must check both with __WCLONE and | |
3737 | without, since the exit status of a cloned process isn't reported | |
3738 | with __WCLONE. */ | |
3739 | if (lp->cloned) | |
3740 | { | |
3741 | do | |
3742 | { | |
dfd4cc63 | 3743 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3744 | if (pid != (pid_t) -1) |
d6b0e80f | 3745 | { |
e85a822c DJ |
3746 | if (debug_linux_nat) |
3747 | fprintf_unfiltered (gdb_stdlog, | |
3748 | "KWC: wait %s received unknown.\n", | |
3749 | target_pid_to_str (lp->ptid)); | |
3750 | /* The Linux kernel sometimes fails to kill a thread | |
3751 | completely after PTRACE_KILL; that goes from the stop | |
3752 | point in do_fork out to the one in | |
3753 | get_signal_to_deliever and waits again. So kill it | |
3754 | again. */ | |
3755 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3756 | } |
3757 | } | |
dfd4cc63 | 3758 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3759 | |
3760 | gdb_assert (pid == -1 && errno == ECHILD); | |
3761 | } | |
3762 | ||
3763 | do | |
3764 | { | |
dfd4cc63 | 3765 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3766 | if (pid != (pid_t) -1) |
d6b0e80f | 3767 | { |
e85a822c DJ |
3768 | if (debug_linux_nat) |
3769 | fprintf_unfiltered (gdb_stdlog, | |
3770 | "KWC: wait %s received unk.\n", | |
3771 | target_pid_to_str (lp->ptid)); | |
3772 | /* See the call to kill_callback above. */ | |
3773 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3774 | } |
3775 | } | |
dfd4cc63 | 3776 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3777 | |
3778 | gdb_assert (pid == -1 && errno == ECHILD); | |
3779 | return 0; | |
3780 | } | |
3781 | ||
3782 | static void | |
7d85a9c0 | 3783 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3784 | { |
f973ed9c DJ |
3785 | struct target_waitstatus last; |
3786 | ptid_t last_ptid; | |
3787 | int status; | |
d6b0e80f | 3788 | |
f973ed9c DJ |
3789 | /* If we're stopped while forking and we haven't followed yet, |
3790 | kill the other task. We need to do this first because the | |
3791 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3792 | |
f973ed9c | 3793 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3794 | |
f973ed9c DJ |
3795 | if (last.kind == TARGET_WAITKIND_FORKED |
3796 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3797 | { | |
dfd4cc63 | 3798 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3799 | wait (&status); |
26cb8b7c PA |
3800 | |
3801 | /* Let the arch-specific native code know this process is | |
3802 | gone. */ | |
dfd4cc63 | 3803 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3804 | } |
3805 | ||
3806 | if (forks_exist_p ()) | |
7feb7d06 | 3807 | linux_fork_killall (); |
f973ed9c DJ |
3808 | else |
3809 | { | |
d90e17a7 | 3810 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3811 | |
4c28f408 PA |
3812 | /* Stop all threads before killing them, since ptrace requires |
3813 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3814 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3815 | /* ... and wait until all of them have reported back that |
3816 | they're no longer running. */ | |
d90e17a7 | 3817 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3818 | |
f973ed9c | 3819 | /* Kill all LWP's ... */ |
d90e17a7 | 3820 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3821 | |
3822 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3823 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3824 | } |
3825 | ||
3826 | target_mourn_inferior (); | |
d6b0e80f AC |
3827 | } |
3828 | ||
3829 | static void | |
136d6dae | 3830 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3831 | { |
26cb8b7c PA |
3832 | int pid = ptid_get_pid (inferior_ptid); |
3833 | ||
3834 | purge_lwp_list (pid); | |
d6b0e80f | 3835 | |
f973ed9c | 3836 | if (! forks_exist_p ()) |
d90e17a7 PA |
3837 | /* Normal case, no other forks available. */ |
3838 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3839 | else |
3840 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3841 | there are other viable forks to debug. Delete the exiting | |
3842 | one and context-switch to the first available. */ | |
3843 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3844 | |
3845 | /* Let the arch-specific native code know this process is gone. */ | |
3846 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3847 | } |
3848 | ||
5b009018 PA |
3849 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3850 | layout of the inferiors' architecture. */ | |
3851 | ||
3852 | static void | |
a5362b9a | 3853 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3854 | { |
3855 | int done = 0; | |
3856 | ||
3857 | if (linux_nat_siginfo_fixup != NULL) | |
3858 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3859 | ||
3860 | /* If there was no callback, or the callback didn't do anything, | |
3861 | then just do a straight memcpy. */ | |
3862 | if (!done) | |
3863 | { | |
3864 | if (direction == 1) | |
a5362b9a | 3865 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3866 | else |
a5362b9a | 3867 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3868 | } |
3869 | } | |
3870 | ||
9b409511 | 3871 | static enum target_xfer_status |
4aa995e1 PA |
3872 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3873 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3874 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3875 | ULONGEST *xfered_len) | |
4aa995e1 | 3876 | { |
4aa995e1 | 3877 | int pid; |
a5362b9a TS |
3878 | siginfo_t siginfo; |
3879 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3880 | |
3881 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3882 | gdb_assert (readbuf || writebuf); | |
3883 | ||
dfd4cc63 | 3884 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3885 | if (pid == 0) |
dfd4cc63 | 3886 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3887 | |
3888 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3889 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3890 | |
3891 | errno = 0; | |
3892 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3893 | if (errno != 0) | |
2ed4b548 | 3894 | return TARGET_XFER_E_IO; |
4aa995e1 | 3895 | |
5b009018 PA |
3896 | /* When GDB is built as a 64-bit application, ptrace writes into |
3897 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3898 | inferior with a 64-bit GDB should look the same as debugging it | |
3899 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3900 | the converted layout, so any read/write will have to be done | |
3901 | post-conversion. */ | |
3902 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3903 | ||
4aa995e1 PA |
3904 | if (offset + len > sizeof (siginfo)) |
3905 | len = sizeof (siginfo) - offset; | |
3906 | ||
3907 | if (readbuf != NULL) | |
5b009018 | 3908 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3909 | else |
3910 | { | |
5b009018 PA |
3911 | memcpy (inf_siginfo + offset, writebuf, len); |
3912 | ||
3913 | /* Convert back to ptrace layout before flushing it out. */ | |
3914 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3915 | ||
4aa995e1 PA |
3916 | errno = 0; |
3917 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3918 | if (errno != 0) | |
2ed4b548 | 3919 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3920 | } |
3921 | ||
9b409511 YQ |
3922 | *xfered_len = len; |
3923 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3924 | } |
3925 | ||
9b409511 | 3926 | static enum target_xfer_status |
10d6c8cd DJ |
3927 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3928 | const char *annex, gdb_byte *readbuf, | |
3929 | const gdb_byte *writebuf, | |
9b409511 | 3930 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3931 | { |
4aa995e1 | 3932 | struct cleanup *old_chain; |
9b409511 | 3933 | enum target_xfer_status xfer; |
d6b0e80f | 3934 | |
4aa995e1 PA |
3935 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3936 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3937 | offset, len, xfered_len); |
4aa995e1 | 3938 | |
c35b1492 PA |
3939 | /* The target is connected but no live inferior is selected. Pass |
3940 | this request down to a lower stratum (e.g., the executable | |
3941 | file). */ | |
3942 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 3943 | return TARGET_XFER_EOF; |
c35b1492 | 3944 | |
4aa995e1 PA |
3945 | old_chain = save_inferior_ptid (); |
3946 | ||
dfd4cc63 LM |
3947 | if (ptid_lwp_p (inferior_ptid)) |
3948 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3949 | |
10d6c8cd | 3950 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3951 | offset, len, xfered_len); |
d6b0e80f AC |
3952 | |
3953 | do_cleanups (old_chain); | |
3954 | return xfer; | |
3955 | } | |
3956 | ||
3957 | static int | |
28439f5e | 3958 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3959 | { |
8c6a60d1 | 3960 | int err, tmp_errno; |
4c28f408 | 3961 | |
dfd4cc63 | 3962 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3963 | |
4c28f408 PA |
3964 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3965 | running thread errors out claiming that the thread doesn't | |
3966 | exist. */ | |
dfd4cc63 | 3967 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3968 | tmp_errno = errno; |
d6b0e80f AC |
3969 | if (debug_linux_nat) |
3970 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3971 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3972 | target_pid_to_str (ptid), |
8c6a60d1 | 3973 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3974 | |
4c28f408 | 3975 | if (err != 0) |
d6b0e80f AC |
3976 | return 0; |
3977 | ||
3978 | return 1; | |
3979 | } | |
3980 | ||
28439f5e PA |
3981 | static int |
3982 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3983 | { | |
3984 | return linux_thread_alive (ptid); | |
3985 | } | |
3986 | ||
d6b0e80f | 3987 | static char * |
117de6a9 | 3988 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3989 | { |
3990 | static char buf[64]; | |
3991 | ||
dfd4cc63 LM |
3992 | if (ptid_lwp_p (ptid) |
3993 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
3994 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 3995 | { |
dfd4cc63 | 3996 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
3997 | return buf; |
3998 | } | |
3999 | ||
4000 | return normal_pid_to_str (ptid); | |
4001 | } | |
4002 | ||
4694da01 | 4003 | static char * |
503a628d | 4004 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 TT |
4005 | { |
4006 | int pid = ptid_get_pid (thr->ptid); | |
4007 | long lwp = ptid_get_lwp (thr->ptid); | |
4008 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4009 | char buf[sizeof (FORMAT) + 30]; | |
4010 | FILE *comm_file; | |
4011 | char *result = NULL; | |
4012 | ||
4013 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4014 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4015 | if (comm_file) |
4016 | { | |
4017 | /* Not exported by the kernel, so we define it here. */ | |
4018 | #define COMM_LEN 16 | |
4019 | static char line[COMM_LEN + 1]; | |
4020 | ||
4021 | if (fgets (line, sizeof (line), comm_file)) | |
4022 | { | |
4023 | char *nl = strchr (line, '\n'); | |
4024 | ||
4025 | if (nl) | |
4026 | *nl = '\0'; | |
4027 | if (*line != '\0') | |
4028 | result = line; | |
4029 | } | |
4030 | ||
4031 | fclose (comm_file); | |
4032 | } | |
4033 | ||
4034 | #undef COMM_LEN | |
4035 | #undef FORMAT | |
4036 | ||
4037 | return result; | |
4038 | } | |
4039 | ||
dba24537 AC |
4040 | /* Accepts an integer PID; Returns a string representing a file that |
4041 | can be opened to get the symbols for the child process. */ | |
4042 | ||
6d8fd2b7 | 4043 | static char * |
8dd27370 | 4044 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 4045 | { |
b4ab256d HZ |
4046 | static char buf[PATH_MAX]; |
4047 | char name[PATH_MAX]; | |
dba24537 | 4048 | |
b4ab256d HZ |
4049 | xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid); |
4050 | memset (buf, 0, PATH_MAX); | |
4051 | if (readlink (name, buf, PATH_MAX - 1) <= 0) | |
4052 | strcpy (buf, name); | |
dba24537 | 4053 | |
b4ab256d | 4054 | return buf; |
dba24537 AC |
4055 | } |
4056 | ||
dba24537 AC |
4057 | /* Records the thread's register state for the corefile note |
4058 | section. */ | |
4059 | ||
4060 | static char * | |
6432734d UW |
4061 | linux_nat_collect_thread_registers (const struct regcache *regcache, |
4062 | ptid_t ptid, bfd *obfd, | |
4063 | char *note_data, int *note_size, | |
2ea28649 | 4064 | enum gdb_signal stop_signal) |
dba24537 | 4065 | { |
6432734d | 4066 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
4f844a66 | 4067 | const struct regset *regset; |
55e969c1 | 4068 | int core_regset_p; |
6432734d UW |
4069 | gdb_gregset_t gregs; |
4070 | gdb_fpregset_t fpregs; | |
4f844a66 DM |
4071 | |
4072 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
dba24537 | 4073 | |
6432734d UW |
4074 | if (core_regset_p |
4075 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
4076 | sizeof (gregs))) | |
4077 | != NULL && regset->collect_regset != NULL) | |
4078 | regset->collect_regset (regset, regcache, -1, &gregs, sizeof (gregs)); | |
4f844a66 | 4079 | else |
6432734d | 4080 | fill_gregset (regcache, &gregs, -1); |
2f2241f1 | 4081 | |
6432734d UW |
4082 | note_data = (char *) elfcore_write_prstatus |
4083 | (obfd, note_data, note_size, ptid_get_lwp (ptid), | |
2ea28649 | 4084 | gdb_signal_to_host (stop_signal), &gregs); |
2f2241f1 | 4085 | |
6432734d UW |
4086 | if (core_regset_p |
4087 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
4088 | sizeof (fpregs))) | |
3e43a32a | 4089 | != NULL && regset->collect_regset != NULL) |
6432734d UW |
4090 | regset->collect_regset (regset, regcache, -1, &fpregs, sizeof (fpregs)); |
4091 | else | |
4092 | fill_fpregset (regcache, &fpregs, -1); | |
17ea7499 | 4093 | |
6432734d UW |
4094 | note_data = (char *) elfcore_write_prfpreg (obfd, note_data, note_size, |
4095 | &fpregs, sizeof (fpregs)); | |
4f844a66 | 4096 | |
dba24537 AC |
4097 | return note_data; |
4098 | } | |
4099 | ||
dba24537 AC |
4100 | /* Fills the "to_make_corefile_note" target vector. Builds the note |
4101 | section for a corefile, and returns it in a malloc buffer. */ | |
4102 | ||
4103 | static char * | |
fc6691b2 TT |
4104 | linux_nat_make_corefile_notes (struct target_ops *self, |
4105 | bfd *obfd, int *note_size) | |
dba24537 | 4106 | { |
6432734d UW |
4107 | /* FIXME: uweigand/2011-10-06: Once all GNU/Linux architectures have been |
4108 | converted to gdbarch_core_regset_sections, this function can go away. */ | |
f5656ead | 4109 | return linux_make_corefile_notes (target_gdbarch (), obfd, note_size, |
6432734d | 4110 | linux_nat_collect_thread_registers); |
dba24537 AC |
4111 | } |
4112 | ||
10d6c8cd DJ |
4113 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4114 | filesystem. Because we can use a single read() call for /proc, this | |
4115 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4116 | but it doesn't support writes. */ | |
4117 | ||
9b409511 | 4118 | static enum target_xfer_status |
10d6c8cd DJ |
4119 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
4120 | const char *annex, gdb_byte *readbuf, | |
4121 | const gdb_byte *writebuf, | |
9b409511 | 4122 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 4123 | { |
10d6c8cd DJ |
4124 | LONGEST ret; |
4125 | int fd; | |
dba24537 AC |
4126 | char filename[64]; |
4127 | ||
10d6c8cd | 4128 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4129 | return 0; |
4130 | ||
4131 | /* Don't bother for one word. */ | |
4132 | if (len < 3 * sizeof (long)) | |
9b409511 | 4133 | return TARGET_XFER_EOF; |
dba24537 AC |
4134 | |
4135 | /* We could keep this file open and cache it - possibly one per | |
4136 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4137 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4138 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4139 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 4140 | if (fd == -1) |
9b409511 | 4141 | return TARGET_XFER_EOF; |
dba24537 AC |
4142 | |
4143 | /* If pread64 is available, use it. It's faster if the kernel | |
4144 | supports it (only one syscall), and it's 64-bit safe even on | |
4145 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4146 | application). */ | |
4147 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4148 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4149 | #else |
10d6c8cd | 4150 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4151 | #endif |
4152 | ret = 0; | |
4153 | else | |
4154 | ret = len; | |
4155 | ||
4156 | close (fd); | |
9b409511 YQ |
4157 | |
4158 | if (ret == 0) | |
4159 | return TARGET_XFER_EOF; | |
4160 | else | |
4161 | { | |
4162 | *xfered_len = ret; | |
4163 | return TARGET_XFER_OK; | |
4164 | } | |
dba24537 AC |
4165 | } |
4166 | ||
efcbbd14 UW |
4167 | |
4168 | /* Enumerate spufs IDs for process PID. */ | |
4169 | static LONGEST | |
b55e14c7 | 4170 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4171 | { |
f5656ead | 4172 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4173 | LONGEST pos = 0; |
4174 | LONGEST written = 0; | |
4175 | char path[128]; | |
4176 | DIR *dir; | |
4177 | struct dirent *entry; | |
4178 | ||
4179 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4180 | dir = opendir (path); | |
4181 | if (!dir) | |
4182 | return -1; | |
4183 | ||
4184 | rewinddir (dir); | |
4185 | while ((entry = readdir (dir)) != NULL) | |
4186 | { | |
4187 | struct stat st; | |
4188 | struct statfs stfs; | |
4189 | int fd; | |
4190 | ||
4191 | fd = atoi (entry->d_name); | |
4192 | if (!fd) | |
4193 | continue; | |
4194 | ||
4195 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4196 | if (stat (path, &st) != 0) | |
4197 | continue; | |
4198 | if (!S_ISDIR (st.st_mode)) | |
4199 | continue; | |
4200 | ||
4201 | if (statfs (path, &stfs) != 0) | |
4202 | continue; | |
4203 | if (stfs.f_type != SPUFS_MAGIC) | |
4204 | continue; | |
4205 | ||
4206 | if (pos >= offset && pos + 4 <= offset + len) | |
4207 | { | |
4208 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4209 | written += 4; | |
4210 | } | |
4211 | pos += 4; | |
4212 | } | |
4213 | ||
4214 | closedir (dir); | |
4215 | return written; | |
4216 | } | |
4217 | ||
4218 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4219 | object type, using the /proc file system. */ | |
9b409511 YQ |
4220 | |
4221 | static enum target_xfer_status | |
efcbbd14 UW |
4222 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4223 | const char *annex, gdb_byte *readbuf, | |
4224 | const gdb_byte *writebuf, | |
9b409511 | 4225 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4226 | { |
4227 | char buf[128]; | |
4228 | int fd = 0; | |
4229 | int ret = -1; | |
dfd4cc63 | 4230 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4231 | |
4232 | if (!annex) | |
4233 | { | |
4234 | if (!readbuf) | |
2ed4b548 | 4235 | return TARGET_XFER_E_IO; |
efcbbd14 | 4236 | else |
9b409511 YQ |
4237 | { |
4238 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4239 | ||
4240 | if (l < 0) | |
4241 | return TARGET_XFER_E_IO; | |
4242 | else if (l == 0) | |
4243 | return TARGET_XFER_EOF; | |
4244 | else | |
4245 | { | |
4246 | *xfered_len = (ULONGEST) l; | |
4247 | return TARGET_XFER_OK; | |
4248 | } | |
4249 | } | |
efcbbd14 UW |
4250 | } |
4251 | ||
4252 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4253 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4254 | if (fd <= 0) |
2ed4b548 | 4255 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4256 | |
4257 | if (offset != 0 | |
4258 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4259 | { | |
4260 | close (fd); | |
9b409511 | 4261 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4262 | } |
4263 | ||
4264 | if (writebuf) | |
4265 | ret = write (fd, writebuf, (size_t) len); | |
4266 | else if (readbuf) | |
4267 | ret = read (fd, readbuf, (size_t) len); | |
4268 | ||
4269 | close (fd); | |
9b409511 YQ |
4270 | |
4271 | if (ret < 0) | |
4272 | return TARGET_XFER_E_IO; | |
4273 | else if (ret == 0) | |
4274 | return TARGET_XFER_EOF; | |
4275 | else | |
4276 | { | |
4277 | *xfered_len = (ULONGEST) ret; | |
4278 | return TARGET_XFER_OK; | |
4279 | } | |
efcbbd14 UW |
4280 | } |
4281 | ||
4282 | ||
dba24537 AC |
4283 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4284 | ||
4285 | static void | |
4286 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4287 | { | |
4288 | int len = strlen (line) - 1; | |
4289 | const char *p; | |
4290 | int signum; | |
4291 | ||
4292 | if (line[len] != '\n') | |
8a3fe4f8 | 4293 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4294 | |
4295 | p = line; | |
4296 | signum = len * 4; | |
4297 | while (len-- > 0) | |
4298 | { | |
4299 | int digit; | |
4300 | ||
4301 | if (*p >= '0' && *p <= '9') | |
4302 | digit = *p - '0'; | |
4303 | else if (*p >= 'a' && *p <= 'f') | |
4304 | digit = *p - 'a' + 10; | |
4305 | else | |
8a3fe4f8 | 4306 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4307 | |
4308 | signum -= 4; | |
4309 | ||
4310 | if (digit & 1) | |
4311 | sigaddset (sigs, signum + 1); | |
4312 | if (digit & 2) | |
4313 | sigaddset (sigs, signum + 2); | |
4314 | if (digit & 4) | |
4315 | sigaddset (sigs, signum + 3); | |
4316 | if (digit & 8) | |
4317 | sigaddset (sigs, signum + 4); | |
4318 | ||
4319 | p++; | |
4320 | } | |
4321 | } | |
4322 | ||
4323 | /* Find process PID's pending signals from /proc/pid/status and set | |
4324 | SIGS to match. */ | |
4325 | ||
4326 | void | |
3e43a32a MS |
4327 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4328 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4329 | { |
4330 | FILE *procfile; | |
d8d2a3ee | 4331 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4332 | struct cleanup *cleanup; |
dba24537 AC |
4333 | |
4334 | sigemptyset (pending); | |
4335 | sigemptyset (blocked); | |
4336 | sigemptyset (ignored); | |
cde33bf1 | 4337 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4338 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4339 | if (procfile == NULL) |
8a3fe4f8 | 4340 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4341 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4342 | |
d8d2a3ee | 4343 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4344 | { |
4345 | /* Normal queued signals are on the SigPnd line in the status | |
4346 | file. However, 2.6 kernels also have a "shared" pending | |
4347 | queue for delivering signals to a thread group, so check for | |
4348 | a ShdPnd line also. | |
4349 | ||
4350 | Unfortunately some Red Hat kernels include the shared pending | |
4351 | queue but not the ShdPnd status field. */ | |
4352 | ||
4353 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
4354 | add_line_to_sigset (buffer + 8, pending); | |
4355 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
4356 | add_line_to_sigset (buffer + 8, pending); | |
4357 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
4358 | add_line_to_sigset (buffer + 8, blocked); | |
4359 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
4360 | add_line_to_sigset (buffer + 8, ignored); | |
4361 | } | |
4362 | ||
7c8a8b04 | 4363 | do_cleanups (cleanup); |
dba24537 AC |
4364 | } |
4365 | ||
9b409511 | 4366 | static enum target_xfer_status |
07e059b5 | 4367 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4368 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4369 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4370 | ULONGEST *xfered_len) | |
07e059b5 | 4371 | { |
07e059b5 VP |
4372 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4373 | ||
9b409511 YQ |
4374 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4375 | if (*xfered_len == 0) | |
4376 | return TARGET_XFER_EOF; | |
4377 | else | |
4378 | return TARGET_XFER_OK; | |
07e059b5 VP |
4379 | } |
4380 | ||
9b409511 | 4381 | static enum target_xfer_status |
10d6c8cd DJ |
4382 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4383 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4384 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4385 | ULONGEST *xfered_len) | |
10d6c8cd | 4386 | { |
9b409511 | 4387 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4388 | |
4389 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4390 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4391 | offset, len, xfered_len); |
10d6c8cd | 4392 | |
07e059b5 VP |
4393 | if (object == TARGET_OBJECT_OSDATA) |
4394 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4395 | offset, len, xfered_len); |
07e059b5 | 4396 | |
efcbbd14 UW |
4397 | if (object == TARGET_OBJECT_SPU) |
4398 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4399 | offset, len, xfered_len); |
efcbbd14 | 4400 | |
8f313923 JK |
4401 | /* GDB calculates all the addresses in possibly larget width of the address. |
4402 | Address width needs to be masked before its final use - either by | |
4403 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4404 | ||
4405 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4406 | ||
4407 | if (object == TARGET_OBJECT_MEMORY) | |
4408 | { | |
f5656ead | 4409 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4410 | |
4411 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4412 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4413 | } | |
4414 | ||
10d6c8cd | 4415 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4416 | offset, len, xfered_len); |
4417 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4418 | return xfer; |
4419 | ||
4420 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4421 | offset, len, xfered_len); |
10d6c8cd DJ |
4422 | } |
4423 | ||
5808517f YQ |
4424 | static void |
4425 | cleanup_target_stop (void *arg) | |
4426 | { | |
4427 | ptid_t *ptid = (ptid_t *) arg; | |
4428 | ||
4429 | gdb_assert (arg != NULL); | |
4430 | ||
4431 | /* Unpause all */ | |
a493e3e2 | 4432 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4433 | } |
4434 | ||
4435 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4436 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4437 | const char *strid) | |
5808517f YQ |
4438 | { |
4439 | char s[IPA_CMD_BUF_SIZE]; | |
4440 | struct cleanup *old_chain; | |
4441 | int pid = ptid_get_pid (inferior_ptid); | |
4442 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4443 | struct static_tracepoint_marker *marker = NULL; | |
4444 | char *p = s; | |
4445 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4446 | ||
4447 | /* Pause all */ | |
4448 | target_stop (ptid); | |
4449 | ||
4450 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4451 | s[sizeof ("qTfSTM")] = 0; | |
4452 | ||
42476b70 | 4453 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4454 | |
4455 | old_chain = make_cleanup (free_current_marker, &marker); | |
4456 | make_cleanup (cleanup_target_stop, &ptid); | |
4457 | ||
4458 | while (*p++ == 'm') | |
4459 | { | |
4460 | if (marker == NULL) | |
4461 | marker = XCNEW (struct static_tracepoint_marker); | |
4462 | ||
4463 | do | |
4464 | { | |
4465 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4466 | ||
4467 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4468 | { | |
4469 | VEC_safe_push (static_tracepoint_marker_p, | |
4470 | markers, marker); | |
4471 | marker = NULL; | |
4472 | } | |
4473 | else | |
4474 | { | |
4475 | release_static_tracepoint_marker (marker); | |
4476 | memset (marker, 0, sizeof (*marker)); | |
4477 | } | |
4478 | } | |
4479 | while (*p++ == ','); /* comma-separated list */ | |
4480 | ||
4481 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4482 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4483 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4484 | p = s; |
4485 | } | |
4486 | ||
4487 | do_cleanups (old_chain); | |
4488 | ||
4489 | return markers; | |
4490 | } | |
4491 | ||
e9efe249 | 4492 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4493 | it with local methods. */ |
4494 | ||
910122bf UW |
4495 | static void |
4496 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4497 | { |
6d8fd2b7 | 4498 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4499 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4500 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4501 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4502 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4503 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4504 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4505 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4506 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4507 | t->to_post_attach = linux_child_post_attach; |
4508 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4509 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; |
4510 | ||
4511 | super_xfer_partial = t->to_xfer_partial; | |
4512 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4513 | |
4514 | t->to_static_tracepoint_markers_by_strid | |
4515 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4516 | } |
4517 | ||
4518 | struct target_ops * | |
4519 | linux_target (void) | |
4520 | { | |
4521 | struct target_ops *t; | |
4522 | ||
4523 | t = inf_ptrace_target (); | |
4524 | linux_target_install_ops (t); | |
4525 | ||
4526 | return t; | |
4527 | } | |
4528 | ||
4529 | struct target_ops * | |
7714d83a | 4530 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4531 | { |
4532 | struct target_ops *t; | |
4533 | ||
4534 | t = inf_ptrace_trad_target (register_u_offset); | |
4535 | linux_target_install_ops (t); | |
10d6c8cd | 4536 | |
10d6c8cd DJ |
4537 | return t; |
4538 | } | |
4539 | ||
b84876c2 PA |
4540 | /* target_is_async_p implementation. */ |
4541 | ||
4542 | static int | |
6a109b6b | 4543 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 PA |
4544 | { |
4545 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4546 | it explicitly with the "set target-async" command. |
b84876c2 | 4547 | Someday, linux will always be async. */ |
3dd5b83d | 4548 | return target_async_permitted; |
b84876c2 PA |
4549 | } |
4550 | ||
4551 | /* target_can_async_p implementation. */ | |
4552 | ||
4553 | static int | |
6a109b6b | 4554 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4555 | { |
4556 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4557 | it explicitly with the "set target-async" command. |
b84876c2 | 4558 | Someday, linux will always be async. */ |
3dd5b83d | 4559 | return target_async_permitted; |
b84876c2 PA |
4560 | } |
4561 | ||
9908b566 | 4562 | static int |
2a9a2795 | 4563 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4564 | { |
4565 | return 1; | |
4566 | } | |
4567 | ||
d90e17a7 PA |
4568 | /* True if we want to support multi-process. To be removed when GDB |
4569 | supports multi-exec. */ | |
4570 | ||
2277426b | 4571 | int linux_multi_process = 1; |
d90e17a7 PA |
4572 | |
4573 | static int | |
86ce2668 | 4574 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4575 | { |
4576 | return linux_multi_process; | |
4577 | } | |
4578 | ||
03583c20 | 4579 | static int |
2bfc0540 | 4580 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4581 | { |
4582 | #ifdef HAVE_PERSONALITY | |
4583 | return 1; | |
4584 | #else | |
4585 | return 0; | |
4586 | #endif | |
4587 | } | |
4588 | ||
b84876c2 PA |
4589 | static int async_terminal_is_ours = 1; |
4590 | ||
4591 | /* target_terminal_inferior implementation. */ | |
4592 | ||
4593 | static void | |
d2f640d4 | 4594 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 PA |
4595 | { |
4596 | if (!target_is_async_p ()) | |
4597 | { | |
4598 | /* Async mode is disabled. */ | |
d6b64346 | 4599 | child_terminal_inferior (self); |
b84876c2 PA |
4600 | return; |
4601 | } | |
4602 | ||
d6b64346 | 4603 | child_terminal_inferior (self); |
b84876c2 | 4604 | |
d9d2d8b6 | 4605 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4606 | if (!async_terminal_is_ours) |
4607 | return; | |
4608 | ||
4609 | delete_file_handler (input_fd); | |
4610 | async_terminal_is_ours = 0; | |
4611 | set_sigint_trap (); | |
4612 | } | |
4613 | ||
4614 | /* target_terminal_ours implementation. */ | |
4615 | ||
2c0b251b | 4616 | static void |
e3594fd1 | 4617 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 PA |
4618 | { |
4619 | if (!target_is_async_p ()) | |
4620 | { | |
4621 | /* Async mode is disabled. */ | |
d6b64346 | 4622 | child_terminal_ours (self); |
b84876c2 PA |
4623 | return; |
4624 | } | |
4625 | ||
4626 | /* GDB should never give the terminal to the inferior if the | |
4627 | inferior is running in the background (run&, continue&, etc.), | |
4628 | but claiming it sure should. */ | |
d6b64346 | 4629 | child_terminal_ours (self); |
b84876c2 | 4630 | |
b84876c2 PA |
4631 | if (async_terminal_is_ours) |
4632 | return; | |
4633 | ||
4634 | clear_sigint_trap (); | |
4635 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4636 | async_terminal_is_ours = 1; | |
4637 | } | |
4638 | ||
4639 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4640 | void *context); | |
4641 | static void *async_client_context; | |
4642 | ||
7feb7d06 PA |
4643 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4644 | so we notice when any child changes state, and notify the | |
4645 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4646 | above to wait for the arrival of a SIGCHLD. */ | |
4647 | ||
b84876c2 | 4648 | static void |
7feb7d06 | 4649 | sigchld_handler (int signo) |
b84876c2 | 4650 | { |
7feb7d06 PA |
4651 | int old_errno = errno; |
4652 | ||
01124a23 DE |
4653 | if (debug_linux_nat) |
4654 | ui_file_write_async_safe (gdb_stdlog, | |
4655 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4656 | |
4657 | if (signo == SIGCHLD | |
4658 | && linux_nat_event_pipe[0] != -1) | |
4659 | async_file_mark (); /* Let the event loop know that there are | |
4660 | events to handle. */ | |
4661 | ||
4662 | errno = old_errno; | |
4663 | } | |
4664 | ||
4665 | /* Callback registered with the target events file descriptor. */ | |
4666 | ||
4667 | static void | |
4668 | handle_target_event (int error, gdb_client_data client_data) | |
4669 | { | |
4670 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4671 | } | |
4672 | ||
4673 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4674 | ||
4675 | static int | |
4676 | linux_async_pipe (int enable) | |
4677 | { | |
4678 | int previous = (linux_nat_event_pipe[0] != -1); | |
4679 | ||
4680 | if (previous != enable) | |
4681 | { | |
4682 | sigset_t prev_mask; | |
4683 | ||
12696c10 PA |
4684 | /* Block child signals while we create/destroy the pipe, as |
4685 | their handler writes to it. */ | |
7feb7d06 PA |
4686 | block_child_signals (&prev_mask); |
4687 | ||
4688 | if (enable) | |
4689 | { | |
614c279d | 4690 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4691 | internal_error (__FILE__, __LINE__, |
4692 | "creating event pipe failed."); | |
4693 | ||
4694 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4695 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4696 | } | |
4697 | else | |
4698 | { | |
4699 | close (linux_nat_event_pipe[0]); | |
4700 | close (linux_nat_event_pipe[1]); | |
4701 | linux_nat_event_pipe[0] = -1; | |
4702 | linux_nat_event_pipe[1] = -1; | |
4703 | } | |
4704 | ||
4705 | restore_child_signals_mask (&prev_mask); | |
4706 | } | |
4707 | ||
4708 | return previous; | |
b84876c2 PA |
4709 | } |
4710 | ||
4711 | /* target_async implementation. */ | |
4712 | ||
4713 | static void | |
6a109b6b TT |
4714 | linux_nat_async (struct target_ops *ops, |
4715 | void (*callback) (enum inferior_event_type event_type, | |
4716 | void *context), | |
4717 | void *context) | |
b84876c2 | 4718 | { |
b84876c2 PA |
4719 | if (callback != NULL) |
4720 | { | |
4721 | async_client_callback = callback; | |
4722 | async_client_context = context; | |
7feb7d06 PA |
4723 | if (!linux_async_pipe (1)) |
4724 | { | |
4725 | add_file_handler (linux_nat_event_pipe[0], | |
4726 | handle_target_event, NULL); | |
4727 | /* There may be pending events to handle. Tell the event loop | |
4728 | to poll them. */ | |
4729 | async_file_mark (); | |
4730 | } | |
b84876c2 PA |
4731 | } |
4732 | else | |
4733 | { | |
4734 | async_client_callback = callback; | |
4735 | async_client_context = context; | |
b84876c2 | 4736 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4737 | linux_async_pipe (0); |
b84876c2 PA |
4738 | } |
4739 | return; | |
4740 | } | |
4741 | ||
a493e3e2 | 4742 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4743 | event came out. */ |
4744 | ||
4c28f408 | 4745 | static int |
252fbfc8 | 4746 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4747 | { |
d90e17a7 | 4748 | if (!lwp->stopped) |
252fbfc8 | 4749 | { |
d90e17a7 PA |
4750 | if (debug_linux_nat) |
4751 | fprintf_unfiltered (gdb_stdlog, | |
4752 | "LNSL: running -> suspending %s\n", | |
4753 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4754 | |
252fbfc8 | 4755 | |
25289eb2 PA |
4756 | if (lwp->last_resume_kind == resume_stop) |
4757 | { | |
4758 | if (debug_linux_nat) | |
4759 | fprintf_unfiltered (gdb_stdlog, | |
4760 | "linux-nat: already stopping LWP %ld at " | |
4761 | "GDB's request\n", | |
4762 | ptid_get_lwp (lwp->ptid)); | |
4763 | return 0; | |
4764 | } | |
252fbfc8 | 4765 | |
25289eb2 PA |
4766 | stop_callback (lwp, NULL); |
4767 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4768 | } |
4769 | else | |
4770 | { | |
4771 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4772 | |
d90e17a7 PA |
4773 | if (debug_linux_nat) |
4774 | { | |
e09875d4 | 4775 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4776 | fprintf_unfiltered (gdb_stdlog, |
4777 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4778 | target_pid_to_str (lwp->ptid)); |
4779 | else | |
3e43a32a MS |
4780 | fprintf_unfiltered (gdb_stdlog, |
4781 | "LNSL: already stopped/no " | |
4782 | "stop_requested yet %s\n", | |
d90e17a7 | 4783 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4784 | } |
4785 | } | |
4c28f408 PA |
4786 | return 0; |
4787 | } | |
4788 | ||
4789 | static void | |
1eab8a48 | 4790 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 PA |
4791 | { |
4792 | if (non_stop) | |
d90e17a7 | 4793 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4794 | else |
1eab8a48 | 4795 | linux_ops->to_stop (linux_ops, ptid); |
4c28f408 PA |
4796 | } |
4797 | ||
d90e17a7 | 4798 | static void |
de90e03d | 4799 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4800 | { |
4801 | /* Unregister from the event loop. */ | |
6a109b6b TT |
4802 | if (linux_nat_is_async_p (NULL)) |
4803 | linux_nat_async (NULL, NULL, 0); | |
d90e17a7 | 4804 | |
d90e17a7 | 4805 | if (linux_ops->to_close) |
de90e03d | 4806 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4807 | |
4808 | super_close (self); | |
d90e17a7 PA |
4809 | } |
4810 | ||
c0694254 PA |
4811 | /* When requests are passed down from the linux-nat layer to the |
4812 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4813 | used. The address space pointer is stored in the inferior object, | |
4814 | but the common code that is passed such ptid can't tell whether | |
4815 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4816 | look up the "main" process id from the lwp here. */ | |
4817 | ||
70221824 | 4818 | static struct address_space * |
c0694254 PA |
4819 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4820 | { | |
4821 | struct lwp_info *lwp; | |
4822 | struct inferior *inf; | |
4823 | int pid; | |
4824 | ||
dfd4cc63 LM |
4825 | pid = ptid_get_lwp (ptid); |
4826 | if (ptid_get_lwp (ptid) == 0) | |
c0694254 PA |
4827 | { |
4828 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4829 | tgid. */ | |
4830 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4831 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4832 | } |
4833 | else | |
4834 | { | |
4835 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4836 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4837 | } |
4838 | ||
4839 | inf = find_inferior_pid (pid); | |
4840 | gdb_assert (inf != NULL); | |
4841 | return inf->aspace; | |
4842 | } | |
4843 | ||
dc146f7c VP |
4844 | /* Return the cached value of the processor core for thread PTID. */ |
4845 | ||
70221824 | 4846 | static int |
dc146f7c VP |
4847 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4848 | { | |
4849 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4850 | |
dc146f7c VP |
4851 | if (info) |
4852 | return info->core; | |
4853 | return -1; | |
4854 | } | |
4855 | ||
f973ed9c DJ |
4856 | void |
4857 | linux_nat_add_target (struct target_ops *t) | |
4858 | { | |
f973ed9c DJ |
4859 | /* Save the provided single-threaded target. We save this in a separate |
4860 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4861 | may have saved a pointer to T; we want to use it for the final | |
4862 | process stratum target. */ | |
4863 | linux_ops_saved = *t; | |
4864 | linux_ops = &linux_ops_saved; | |
4865 | ||
4866 | /* Override some methods for multithreading. */ | |
b84876c2 | 4867 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4868 | t->to_attach = linux_nat_attach; |
4869 | t->to_detach = linux_nat_detach; | |
4870 | t->to_resume = linux_nat_resume; | |
4871 | t->to_wait = linux_nat_wait; | |
2455069d | 4872 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4873 | t->to_xfer_partial = linux_nat_xfer_partial; |
4874 | t->to_kill = linux_nat_kill; | |
4875 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4876 | t->to_thread_alive = linux_nat_thread_alive; | |
4877 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4878 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4879 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4880 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4881 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4882 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
f973ed9c | 4883 | |
b84876c2 PA |
4884 | t->to_can_async_p = linux_nat_can_async_p; |
4885 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4886 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4887 | t->to_async = linux_nat_async; |
b84876c2 PA |
4888 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4889 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4890 | |
4891 | super_close = t->to_close; | |
d90e17a7 | 4892 | t->to_close = linux_nat_close; |
b84876c2 | 4893 | |
4c28f408 PA |
4894 | /* Methods for non-stop support. */ |
4895 | t->to_stop = linux_nat_stop; | |
4896 | ||
d90e17a7 PA |
4897 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4898 | ||
03583c20 UW |
4899 | t->to_supports_disable_randomization |
4900 | = linux_nat_supports_disable_randomization; | |
4901 | ||
dc146f7c VP |
4902 | t->to_core_of_thread = linux_nat_core_of_thread; |
4903 | ||
f973ed9c DJ |
4904 | /* We don't change the stratum; this target will sit at |
4905 | process_stratum and thread_db will set at thread_stratum. This | |
4906 | is a little strange, since this is a multi-threaded-capable | |
4907 | target, but we want to be on the stack below thread_db, and we | |
4908 | also want to be used for single-threaded processes. */ | |
4909 | ||
4910 | add_target (t); | |
f973ed9c DJ |
4911 | } |
4912 | ||
9f0bdab8 DJ |
4913 | /* Register a method to call whenever a new thread is attached. */ |
4914 | void | |
7b50312a PA |
4915 | linux_nat_set_new_thread (struct target_ops *t, |
4916 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4917 | { |
4918 | /* Save the pointer. We only support a single registered instance | |
4919 | of the GNU/Linux native target, so we do not need to map this to | |
4920 | T. */ | |
4921 | linux_nat_new_thread = new_thread; | |
4922 | } | |
4923 | ||
26cb8b7c PA |
4924 | /* See declaration in linux-nat.h. */ |
4925 | ||
4926 | void | |
4927 | linux_nat_set_new_fork (struct target_ops *t, | |
4928 | linux_nat_new_fork_ftype *new_fork) | |
4929 | { | |
4930 | /* Save the pointer. */ | |
4931 | linux_nat_new_fork = new_fork; | |
4932 | } | |
4933 | ||
4934 | /* See declaration in linux-nat.h. */ | |
4935 | ||
4936 | void | |
4937 | linux_nat_set_forget_process (struct target_ops *t, | |
4938 | linux_nat_forget_process_ftype *fn) | |
4939 | { | |
4940 | /* Save the pointer. */ | |
4941 | linux_nat_forget_process_hook = fn; | |
4942 | } | |
4943 | ||
4944 | /* See declaration in linux-nat.h. */ | |
4945 | ||
4946 | void | |
4947 | linux_nat_forget_process (pid_t pid) | |
4948 | { | |
4949 | if (linux_nat_forget_process_hook != NULL) | |
4950 | linux_nat_forget_process_hook (pid); | |
4951 | } | |
4952 | ||
5b009018 PA |
4953 | /* Register a method that converts a siginfo object between the layout |
4954 | that ptrace returns, and the layout in the architecture of the | |
4955 | inferior. */ | |
4956 | void | |
4957 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4958 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4959 | gdb_byte *, |
4960 | int)) | |
4961 | { | |
4962 | /* Save the pointer. */ | |
4963 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4964 | } | |
4965 | ||
7b50312a PA |
4966 | /* Register a method to call prior to resuming a thread. */ |
4967 | ||
4968 | void | |
4969 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4970 | void (*prepare_to_resume) (struct lwp_info *)) | |
4971 | { | |
4972 | /* Save the pointer. */ | |
4973 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4974 | } | |
4975 | ||
f865ee35 JK |
4976 | /* See linux-nat.h. */ |
4977 | ||
4978 | int | |
4979 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4980 | { |
da559b09 | 4981 | int pid; |
9f0bdab8 | 4982 | |
dfd4cc63 | 4983 | pid = ptid_get_lwp (ptid); |
da559b09 | 4984 | if (pid == 0) |
dfd4cc63 | 4985 | pid = ptid_get_pid (ptid); |
f865ee35 | 4986 | |
da559b09 JK |
4987 | errno = 0; |
4988 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4989 | if (errno != 0) | |
4990 | { | |
4991 | memset (siginfo, 0, sizeof (*siginfo)); | |
4992 | return 0; | |
4993 | } | |
f865ee35 | 4994 | return 1; |
9f0bdab8 DJ |
4995 | } |
4996 | ||
2c0b251b PA |
4997 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
4998 | extern initialize_file_ftype _initialize_linux_nat; | |
4999 | ||
d6b0e80f AC |
5000 | void |
5001 | _initialize_linux_nat (void) | |
5002 | { | |
ccce17b0 YQ |
5003 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
5004 | &debug_linux_nat, _("\ | |
b84876c2 PA |
5005 | Set debugging of GNU/Linux lwp module."), _("\ |
5006 | Show debugging of GNU/Linux lwp module."), _("\ | |
5007 | Enables printf debugging output."), | |
ccce17b0 YQ |
5008 | NULL, |
5009 | show_debug_linux_nat, | |
5010 | &setdebuglist, &showdebuglist); | |
b84876c2 | 5011 | |
b84876c2 | 5012 | /* Save this mask as the default. */ |
d6b0e80f AC |
5013 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
5014 | ||
7feb7d06 PA |
5015 | /* Install a SIGCHLD handler. */ |
5016 | sigchld_action.sa_handler = sigchld_handler; | |
5017 | sigemptyset (&sigchld_action.sa_mask); | |
5018 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
5019 | |
5020 | /* Make it the default. */ | |
7feb7d06 | 5021 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5022 | |
5023 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5024 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5025 | sigdelset (&suspend_mask, SIGCHLD); | |
5026 | ||
7feb7d06 | 5027 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5028 | } |
5029 | \f | |
5030 | ||
5031 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5032 | the GNU/Linux Threads library and therefore doesn't really belong | |
5033 | here. */ | |
5034 | ||
5035 | /* Read variable NAME in the target and return its value if found. | |
5036 | Otherwise return zero. It is assumed that the type of the variable | |
5037 | is `int'. */ | |
5038 | ||
5039 | static int | |
5040 | get_signo (const char *name) | |
5041 | { | |
3b7344d5 | 5042 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5043 | int signo; |
5044 | ||
5045 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5046 | if (ms.minsym == NULL) |
d6b0e80f AC |
5047 | return 0; |
5048 | ||
77e371c0 | 5049 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5050 | sizeof (signo)) != 0) |
5051 | return 0; | |
5052 | ||
5053 | return signo; | |
5054 | } | |
5055 | ||
5056 | /* Return the set of signals used by the threads library in *SET. */ | |
5057 | ||
5058 | void | |
5059 | lin_thread_get_thread_signals (sigset_t *set) | |
5060 | { | |
5061 | struct sigaction action; | |
5062 | int restart, cancel; | |
5063 | ||
b84876c2 | 5064 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5065 | sigemptyset (set); |
5066 | ||
5067 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5068 | cancel = get_signo ("__pthread_sig_cancel"); |
5069 | ||
5070 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5071 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5072 | not provide any way for the debugger to query the signal numbers - | |
5073 | fortunately they don't change! */ | |
5074 | ||
d6b0e80f | 5075 | if (restart == 0) |
17fbb0bd | 5076 | restart = __SIGRTMIN; |
d6b0e80f | 5077 | |
d6b0e80f | 5078 | if (cancel == 0) |
17fbb0bd | 5079 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5080 | |
5081 | sigaddset (set, restart); | |
5082 | sigaddset (set, cancel); | |
5083 | ||
5084 | /* The GNU/Linux Threads library makes terminating threads send a | |
5085 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5086 | those (to prevent them from terminating GDB itself, which is | |
5087 | likely to be their default action) and treat them the same way as | |
5088 | SIGCHLD. */ | |
5089 | ||
5090 | action.sa_handler = sigchld_handler; | |
5091 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5092 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5093 | sigaction (cancel, &action, NULL); |
5094 | ||
5095 | /* We block the "cancel" signal throughout this code ... */ | |
5096 | sigaddset (&blocked_mask, cancel); | |
5097 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5098 | ||
5099 | /* ... except during a sigsuspend. */ | |
5100 | sigdelset (&suspend_mask, cancel); | |
5101 | } |