Commit | Line | Data |
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3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
ecd75fc8 | 3 | Copyright (C) 2001-2014 Free Software Foundation, Inc. |
3993f6b1 DJ |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
3993f6b1 DJ |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3993f6b1 DJ |
19 | |
20 | #include "defs.h" | |
21 | #include "inferior.h" | |
45741a9c | 22 | #include "infrun.h" |
3993f6b1 | 23 | #include "target.h" |
96d7229d LM |
24 | #include "nat/linux-nat.h" |
25 | #include "nat/linux-waitpid.h" | |
3993f6b1 | 26 | #include "gdb_wait.h" |
d6b0e80f AC |
27 | #ifdef HAVE_TKILL_SYSCALL |
28 | #include <unistd.h> | |
29 | #include <sys/syscall.h> | |
30 | #endif | |
3993f6b1 | 31 | #include <sys/ptrace.h> |
0274a8ce | 32 | #include "linux-nat.h" |
125f8a3d GB |
33 | #include "nat/linux-ptrace.h" |
34 | #include "nat/linux-procfs.h" | |
ac264b3b | 35 | #include "linux-fork.h" |
d6b0e80f AC |
36 | #include "gdbthread.h" |
37 | #include "gdbcmd.h" | |
38 | #include "regcache.h" | |
4f844a66 | 39 | #include "regset.h" |
dab06dbe | 40 | #include "inf-child.h" |
10d6c8cd DJ |
41 | #include "inf-ptrace.h" |
42 | #include "auxv.h" | |
1777feb0 | 43 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
44 | #include "elf-bfd.h" /* for elfcore_write_* */ |
45 | #include "gregset.h" /* for gregset */ | |
46 | #include "gdbcore.h" /* for get_exec_file */ | |
47 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 48 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 49 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
50 | #include "inf-loop.h" |
51 | #include "event-loop.h" | |
52 | #include "event-top.h" | |
07e059b5 VP |
53 | #include <pwd.h> |
54 | #include <sys/types.h> | |
2978b111 | 55 | #include <dirent.h> |
07e059b5 | 56 | #include "xml-support.h" |
191c4426 | 57 | #include "terminal.h" |
efcbbd14 | 58 | #include <sys/vfs.h> |
6c95b8df | 59 | #include "solib.h" |
125f8a3d | 60 | #include "nat/linux-osdata.h" |
6432734d | 61 | #include "linux-tdep.h" |
7dcd53a0 | 62 | #include "symfile.h" |
5808517f YQ |
63 | #include "agent.h" |
64 | #include "tracepoint.h" | |
87b0bb13 | 65 | #include "exceptions.h" |
87b0bb13 | 66 | #include "buffer.h" |
6ecd4729 | 67 | #include "target-descriptions.h" |
614c279d | 68 | #include "filestuff.h" |
77e371c0 | 69 | #include "objfiles.h" |
efcbbd14 UW |
70 | |
71 | #ifndef SPUFS_MAGIC | |
72 | #define SPUFS_MAGIC 0x23c9b64e | |
73 | #endif | |
dba24537 | 74 | |
10568435 JK |
75 | #ifdef HAVE_PERSONALITY |
76 | # include <sys/personality.h> | |
77 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
78 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
79 | # endif | |
80 | #endif /* HAVE_PERSONALITY */ | |
81 | ||
1777feb0 | 82 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
83 | |
84 | Waiting for events in sync mode | |
85 | =============================== | |
86 | ||
87 | When waiting for an event in a specific thread, we just use waitpid, passing | |
88 | the specific pid, and not passing WNOHANG. | |
89 | ||
1777feb0 | 90 | When waiting for an event in all threads, waitpid is not quite good. Prior to |
8a77dff3 | 91 | version 2.4, Linux can either wait for event in main thread, or in secondary |
1777feb0 | 92 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might |
8a77dff3 VP |
93 | miss an event. The solution is to use non-blocking waitpid, together with |
94 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
1777feb0 | 95 | process, if any. Second, we use non-blocking waitpid with the __WCLONED |
8a77dff3 VP |
96 | flag to check for events in cloned processes. If nothing is found, we use |
97 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
98 | happened to a child process -- and SIGCHLD will be delivered both for events | |
99 | in main debugged process and in cloned processes. As soon as we know there's | |
3e43a32a MS |
100 | an event, we get back to calling nonblocking waitpid with and without |
101 | __WCLONED. | |
8a77dff3 VP |
102 | |
103 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
1777feb0 | 104 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's |
8a77dff3 VP |
105 | blocked, the signal becomes pending and sigsuspend immediately |
106 | notices it and returns. | |
107 | ||
108 | Waiting for events in async mode | |
109 | ================================ | |
110 | ||
7feb7d06 PA |
111 | In async mode, GDB should always be ready to handle both user input |
112 | and target events, so neither blocking waitpid nor sigsuspend are | |
113 | viable options. Instead, we should asynchronously notify the GDB main | |
114 | event loop whenever there's an unprocessed event from the target. We | |
115 | detect asynchronous target events by handling SIGCHLD signals. To | |
116 | notify the event loop about target events, the self-pipe trick is used | |
117 | --- a pipe is registered as waitable event source in the event loop, | |
118 | the event loop select/poll's on the read end of this pipe (as well on | |
119 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
120 | byte to this pipe. This is more portable than relying on | |
121 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
122 | emulates them with select/poll+sigprocmask, and that is racy | |
123 | (a.k.a. plain broken). | |
124 | ||
125 | Obviously, if we fail to notify the event loop if there's a target | |
126 | event, it's bad. OTOH, if we notify the event loop when there's no | |
127 | event from the target, linux_nat_wait will detect that there's no real | |
128 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
129 | This is mostly harmless, but it will waste time and is better avoided. | |
130 | ||
131 | The main design point is that every time GDB is outside linux-nat.c, | |
132 | we have a SIGCHLD handler installed that is called when something | |
133 | happens to the target and notifies the GDB event loop. Whenever GDB | |
134 | core decides to handle the event, and calls into linux-nat.c, we | |
135 | process things as in sync mode, except that the we never block in | |
136 | sigsuspend. | |
137 | ||
138 | While processing an event, we may end up momentarily blocked in | |
139 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
140 | return quickly. E.g., in all-stop mode, before reporting to the core | |
141 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
142 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
143 | Note that this is different from blocking indefinitely waiting for the | |
144 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
145 | |
146 | Use of signals | |
147 | ============== | |
148 | ||
149 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
150 | signal is not entirely significant; we just need for a signal to be delivered, | |
151 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
152 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
153 | be queued once; we do not keep track of other sources of SIGSTOP. | |
154 | ||
155 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
156 | use them, because they have special behavior when the signal is generated - | |
157 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
158 | kills the entire thread group. | |
159 | ||
160 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
161 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
162 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
163 | ||
164 | We could use a real-time signal instead. This would solve those problems; we | |
165 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
166 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
167 | generates it, and there are races with trying to find a signal that is not | |
168 | blocked. */ | |
a0ef4274 | 169 | |
dba24537 AC |
170 | #ifndef O_LARGEFILE |
171 | #define O_LARGEFILE 0 | |
172 | #endif | |
0274a8ce | 173 | |
10d6c8cd DJ |
174 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
175 | the use of the multi-threaded target. */ | |
176 | static struct target_ops *linux_ops; | |
f973ed9c | 177 | static struct target_ops linux_ops_saved; |
10d6c8cd | 178 | |
9f0bdab8 | 179 | /* The method to call, if any, when a new thread is attached. */ |
7b50312a PA |
180 | static void (*linux_nat_new_thread) (struct lwp_info *); |
181 | ||
26cb8b7c PA |
182 | /* The method to call, if any, when a new fork is attached. */ |
183 | static linux_nat_new_fork_ftype *linux_nat_new_fork; | |
184 | ||
185 | /* The method to call, if any, when a process is no longer | |
186 | attached. */ | |
187 | static linux_nat_forget_process_ftype *linux_nat_forget_process_hook; | |
188 | ||
7b50312a PA |
189 | /* Hook to call prior to resuming a thread. */ |
190 | static void (*linux_nat_prepare_to_resume) (struct lwp_info *); | |
9f0bdab8 | 191 | |
5b009018 PA |
192 | /* The method to call, if any, when the siginfo object needs to be |
193 | converted between the layout returned by ptrace, and the layout in | |
194 | the architecture of the inferior. */ | |
a5362b9a | 195 | static int (*linux_nat_siginfo_fixup) (siginfo_t *, |
5b009018 PA |
196 | gdb_byte *, |
197 | int); | |
198 | ||
ac264b3b MS |
199 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
200 | Called by our to_xfer_partial. */ | |
4ac248ca | 201 | static target_xfer_partial_ftype *super_xfer_partial; |
10d6c8cd | 202 | |
6a3cb8e8 PA |
203 | /* The saved to_close method, inherited from inf-ptrace.c. |
204 | Called by our to_close. */ | |
205 | static void (*super_close) (struct target_ops *); | |
206 | ||
ccce17b0 | 207 | static unsigned int debug_linux_nat; |
920d2a44 AC |
208 | static void |
209 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
210 | struct cmd_list_element *c, const char *value) | |
211 | { | |
212 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
213 | value); | |
214 | } | |
d6b0e80f | 215 | |
ae087d01 DJ |
216 | struct simple_pid_list |
217 | { | |
218 | int pid; | |
3d799a95 | 219 | int status; |
ae087d01 DJ |
220 | struct simple_pid_list *next; |
221 | }; | |
222 | struct simple_pid_list *stopped_pids; | |
223 | ||
3dd5b83d PA |
224 | /* Async mode support. */ |
225 | ||
b84876c2 PA |
226 | /* The read/write ends of the pipe registered as waitable file in the |
227 | event loop. */ | |
228 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
229 | ||
7feb7d06 | 230 | /* Flush the event pipe. */ |
b84876c2 | 231 | |
7feb7d06 PA |
232 | static void |
233 | async_file_flush (void) | |
b84876c2 | 234 | { |
7feb7d06 PA |
235 | int ret; |
236 | char buf; | |
b84876c2 | 237 | |
7feb7d06 | 238 | do |
b84876c2 | 239 | { |
7feb7d06 | 240 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 241 | } |
7feb7d06 | 242 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
243 | } |
244 | ||
7feb7d06 PA |
245 | /* Put something (anything, doesn't matter what, or how much) in event |
246 | pipe, so that the select/poll in the event-loop realizes we have | |
247 | something to process. */ | |
252fbfc8 | 248 | |
b84876c2 | 249 | static void |
7feb7d06 | 250 | async_file_mark (void) |
b84876c2 | 251 | { |
7feb7d06 | 252 | int ret; |
b84876c2 | 253 | |
7feb7d06 PA |
254 | /* It doesn't really matter what the pipe contains, as long we end |
255 | up with something in it. Might as well flush the previous | |
256 | left-overs. */ | |
257 | async_file_flush (); | |
b84876c2 | 258 | |
7feb7d06 | 259 | do |
b84876c2 | 260 | { |
7feb7d06 | 261 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 262 | } |
7feb7d06 | 263 | while (ret == -1 && errno == EINTR); |
b84876c2 | 264 | |
7feb7d06 PA |
265 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
266 | be awakened anyway. */ | |
b84876c2 PA |
267 | } |
268 | ||
7feb7d06 PA |
269 | static int kill_lwp (int lwpid, int signo); |
270 | ||
271 | static int stop_callback (struct lwp_info *lp, void *data); | |
272 | ||
273 | static void block_child_signals (sigset_t *prev_mask); | |
274 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
275 | |
276 | struct lwp_info; | |
277 | static struct lwp_info *add_lwp (ptid_t ptid); | |
278 | static void purge_lwp_list (int pid); | |
4403d8e9 | 279 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
280 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
281 | ||
ae087d01 DJ |
282 | \f |
283 | /* Trivial list manipulation functions to keep track of a list of | |
284 | new stopped processes. */ | |
285 | static void | |
3d799a95 | 286 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
287 | { |
288 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
e0881a8e | 289 | |
ae087d01 | 290 | new_pid->pid = pid; |
3d799a95 | 291 | new_pid->status = status; |
ae087d01 DJ |
292 | new_pid->next = *listp; |
293 | *listp = new_pid; | |
294 | } | |
295 | ||
84636d28 PA |
296 | static int |
297 | in_pid_list_p (struct simple_pid_list *list, int pid) | |
298 | { | |
299 | struct simple_pid_list *p; | |
300 | ||
301 | for (p = list; p != NULL; p = p->next) | |
302 | if (p->pid == pid) | |
303 | return 1; | |
304 | return 0; | |
305 | } | |
306 | ||
ae087d01 | 307 | static int |
46a96992 | 308 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
309 | { |
310 | struct simple_pid_list **p; | |
311 | ||
312 | for (p = listp; *p != NULL; p = &(*p)->next) | |
313 | if ((*p)->pid == pid) | |
314 | { | |
315 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 316 | |
46a96992 | 317 | *statusp = (*p)->status; |
ae087d01 DJ |
318 | xfree (*p); |
319 | *p = next; | |
320 | return 1; | |
321 | } | |
322 | return 0; | |
323 | } | |
324 | ||
96d7229d LM |
325 | /* Initialize ptrace warnings and check for supported ptrace |
326 | features given PID. */ | |
3993f6b1 DJ |
327 | |
328 | static void | |
96d7229d | 329 | linux_init_ptrace (pid_t pid) |
3993f6b1 | 330 | { |
96d7229d LM |
331 | linux_enable_event_reporting (pid); |
332 | linux_ptrace_init_warnings (); | |
4de4c07c DJ |
333 | } |
334 | ||
6d8fd2b7 | 335 | static void |
f045800c | 336 | linux_child_post_attach (struct target_ops *self, int pid) |
4de4c07c | 337 | { |
96d7229d | 338 | linux_init_ptrace (pid); |
4de4c07c DJ |
339 | } |
340 | ||
10d6c8cd | 341 | static void |
2e97a79e | 342 | linux_child_post_startup_inferior (struct target_ops *self, ptid_t ptid) |
4de4c07c | 343 | { |
96d7229d | 344 | linux_init_ptrace (ptid_get_pid (ptid)); |
4de4c07c DJ |
345 | } |
346 | ||
4403d8e9 JK |
347 | /* Return the number of known LWPs in the tgid given by PID. */ |
348 | ||
349 | static int | |
350 | num_lwps (int pid) | |
351 | { | |
352 | int count = 0; | |
353 | struct lwp_info *lp; | |
354 | ||
355 | for (lp = lwp_list; lp; lp = lp->next) | |
356 | if (ptid_get_pid (lp->ptid) == pid) | |
357 | count++; | |
358 | ||
359 | return count; | |
360 | } | |
361 | ||
362 | /* Call delete_lwp with prototype compatible for make_cleanup. */ | |
363 | ||
364 | static void | |
365 | delete_lwp_cleanup (void *lp_voidp) | |
366 | { | |
367 | struct lwp_info *lp = lp_voidp; | |
368 | ||
369 | delete_lwp (lp->ptid); | |
370 | } | |
371 | ||
6d8fd2b7 | 372 | static int |
07107ca6 LM |
373 | linux_child_follow_fork (struct target_ops *ops, int follow_child, |
374 | int detach_fork) | |
3993f6b1 | 375 | { |
9016a515 | 376 | int has_vforked; |
4de4c07c DJ |
377 | int parent_pid, child_pid; |
378 | ||
e58b0e63 PA |
379 | has_vforked = (inferior_thread ()->pending_follow.kind |
380 | == TARGET_WAITKIND_VFORKED); | |
381 | parent_pid = ptid_get_lwp (inferior_ptid); | |
d3587048 | 382 | if (parent_pid == 0) |
e58b0e63 | 383 | parent_pid = ptid_get_pid (inferior_ptid); |
dfd4cc63 LM |
384 | child_pid |
385 | = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid); | |
4de4c07c | 386 | |
6c95b8df PA |
387 | if (has_vforked |
388 | && !non_stop /* Non-stop always resumes both branches. */ | |
389 | && (!target_is_async_p () || sync_execution) | |
390 | && !(follow_child || detach_fork || sched_multi)) | |
391 | { | |
392 | /* The parent stays blocked inside the vfork syscall until the | |
393 | child execs or exits. If we don't let the child run, then | |
394 | the parent stays blocked. If we're telling the parent to run | |
395 | in the foreground, the user will not be able to ctrl-c to get | |
396 | back the terminal, effectively hanging the debug session. */ | |
ac74f770 MS |
397 | fprintf_filtered (gdb_stderr, _("\ |
398 | Can not resume the parent process over vfork in the foreground while\n\ | |
399 | holding the child stopped. Try \"set detach-on-fork\" or \ | |
400 | \"set schedule-multiple\".\n")); | |
401 | /* FIXME output string > 80 columns. */ | |
6c95b8df PA |
402 | return 1; |
403 | } | |
404 | ||
4de4c07c DJ |
405 | if (! follow_child) |
406 | { | |
6c95b8df | 407 | struct lwp_info *child_lp = NULL; |
4de4c07c | 408 | |
1777feb0 | 409 | /* We're already attached to the parent, by default. */ |
4de4c07c | 410 | |
ac264b3b MS |
411 | /* Detach new forked process? */ |
412 | if (detach_fork) | |
f75c00e4 | 413 | { |
4403d8e9 | 414 | struct cleanup *old_chain; |
9caaaa83 | 415 | int status = W_STOPCODE (0); |
4403d8e9 | 416 | |
6c95b8df PA |
417 | /* Before detaching from the child, remove all breakpoints |
418 | from it. If we forked, then this has already been taken | |
419 | care of by infrun.c. If we vforked however, any | |
420 | breakpoint inserted in the parent is visible in the | |
421 | child, even those added while stopped in a vfork | |
422 | catchpoint. This will remove the breakpoints from the | |
423 | parent also, but they'll be reinserted below. */ | |
424 | if (has_vforked) | |
425 | { | |
426 | /* keep breakpoints list in sync. */ | |
dfd4cc63 | 427 | remove_breakpoints_pid (ptid_get_pid (inferior_ptid)); |
6c95b8df PA |
428 | } |
429 | ||
e85a822c | 430 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
431 | { |
432 | target_terminal_ours (); | |
433 | fprintf_filtered (gdb_stdlog, | |
3e43a32a MS |
434 | "Detaching after fork from " |
435 | "child process %d.\n", | |
ac264b3b MS |
436 | child_pid); |
437 | } | |
4de4c07c | 438 | |
4403d8e9 JK |
439 | old_chain = save_inferior_ptid (); |
440 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
441 | ||
442 | child_lp = add_lwp (inferior_ptid); | |
443 | child_lp->stopped = 1; | |
444 | child_lp->last_resume_kind = resume_stop; | |
445 | make_cleanup (delete_lwp_cleanup, child_lp); | |
446 | ||
4403d8e9 JK |
447 | if (linux_nat_prepare_to_resume != NULL) |
448 | linux_nat_prepare_to_resume (child_lp); | |
c077881a HZ |
449 | |
450 | /* When debugging an inferior in an architecture that supports | |
451 | hardware single stepping on a kernel without commit | |
452 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
453 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
454 | set if the parent process had them set. | |
455 | To work around this, single step the child process | |
456 | once before detaching to clear the flags. */ | |
457 | ||
458 | if (!gdbarch_software_single_step_p (target_thread_architecture | |
459 | (child_lp->ptid))) | |
460 | { | |
c077881a HZ |
461 | linux_disable_event_reporting (child_pid); |
462 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
463 | perror_with_name (_("Couldn't do single step")); | |
464 | if (my_waitpid (child_pid, &status, 0) < 0) | |
465 | perror_with_name (_("Couldn't wait vfork process")); | |
466 | } | |
467 | ||
468 | if (WIFSTOPPED (status)) | |
9caaaa83 PA |
469 | { |
470 | int signo; | |
471 | ||
472 | signo = WSTOPSIG (status); | |
473 | if (signo != 0 | |
474 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
475 | signo = 0; | |
476 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
477 | } | |
4403d8e9 JK |
478 | |
479 | do_cleanups (old_chain); | |
ac264b3b MS |
480 | } |
481 | else | |
482 | { | |
77435e4c | 483 | struct inferior *parent_inf, *child_inf; |
2277426b | 484 | struct cleanup *old_chain; |
7f9f62ba PA |
485 | |
486 | /* Add process to GDB's tables. */ | |
77435e4c PA |
487 | child_inf = add_inferior (child_pid); |
488 | ||
e58b0e63 | 489 | parent_inf = current_inferior (); |
77435e4c | 490 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 491 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
492 | child_inf->gdbarch = parent_inf->gdbarch; |
493 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7f9f62ba | 494 | |
2277426b | 495 | old_chain = save_inferior_ptid (); |
6c95b8df | 496 | save_current_program_space (); |
2277426b PA |
497 | |
498 | inferior_ptid = ptid_build (child_pid, child_pid, 0); | |
499 | add_thread (inferior_ptid); | |
6c95b8df PA |
500 | child_lp = add_lwp (inferior_ptid); |
501 | child_lp->stopped = 1; | |
25289eb2 | 502 | child_lp->last_resume_kind = resume_stop; |
7dcd53a0 | 503 | child_inf->symfile_flags = SYMFILE_NO_READ; |
2277426b | 504 | |
6c95b8df PA |
505 | /* If this is a vfork child, then the address-space is |
506 | shared with the parent. */ | |
507 | if (has_vforked) | |
508 | { | |
509 | child_inf->pspace = parent_inf->pspace; | |
510 | child_inf->aspace = parent_inf->aspace; | |
511 | ||
512 | /* The parent will be frozen until the child is done | |
513 | with the shared region. Keep track of the | |
514 | parent. */ | |
515 | child_inf->vfork_parent = parent_inf; | |
516 | child_inf->pending_detach = 0; | |
517 | parent_inf->vfork_child = child_inf; | |
518 | parent_inf->pending_detach = 0; | |
519 | } | |
520 | else | |
521 | { | |
522 | child_inf->aspace = new_address_space (); | |
523 | child_inf->pspace = add_program_space (child_inf->aspace); | |
524 | child_inf->removable = 1; | |
525 | set_current_program_space (child_inf->pspace); | |
526 | clone_program_space (child_inf->pspace, parent_inf->pspace); | |
527 | ||
528 | /* Let the shared library layer (solib-svr4) learn about | |
529 | this new process, relocate the cloned exec, pull in | |
530 | shared libraries, and install the solib event | |
531 | breakpoint. If a "cloned-VM" event was propagated | |
532 | better throughout the core, this wouldn't be | |
533 | required. */ | |
268a4a75 | 534 | solib_create_inferior_hook (0); |
6c95b8df PA |
535 | } |
536 | ||
537 | /* Let the thread_db layer learn about this new process. */ | |
2277426b PA |
538 | check_for_thread_db (); |
539 | ||
540 | do_cleanups (old_chain); | |
ac264b3b | 541 | } |
9016a515 DJ |
542 | |
543 | if (has_vforked) | |
544 | { | |
3ced3da4 | 545 | struct lwp_info *parent_lp; |
6c95b8df PA |
546 | struct inferior *parent_inf; |
547 | ||
548 | parent_inf = current_inferior (); | |
549 | ||
550 | /* If we detached from the child, then we have to be careful | |
551 | to not insert breakpoints in the parent until the child | |
552 | is done with the shared memory region. However, if we're | |
553 | staying attached to the child, then we can and should | |
554 | insert breakpoints, so that we can debug it. A | |
555 | subsequent child exec or exit is enough to know when does | |
556 | the child stops using the parent's address space. */ | |
557 | parent_inf->waiting_for_vfork_done = detach_fork; | |
56710373 | 558 | parent_inf->pspace->breakpoints_not_allowed = detach_fork; |
6c95b8df | 559 | |
3ced3da4 | 560 | parent_lp = find_lwp_pid (pid_to_ptid (parent_pid)); |
96d7229d | 561 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 562 | |
96d7229d | 563 | if (linux_supports_tracevforkdone ()) |
9016a515 | 564 | { |
6c95b8df PA |
565 | if (debug_linux_nat) |
566 | fprintf_unfiltered (gdb_stdlog, | |
567 | "LCFF: waiting for VFORK_DONE on %d\n", | |
568 | parent_pid); | |
3ced3da4 | 569 | parent_lp->stopped = 1; |
9016a515 | 570 | |
6c95b8df PA |
571 | /* We'll handle the VFORK_DONE event like any other |
572 | event, in target_wait. */ | |
9016a515 DJ |
573 | } |
574 | else | |
575 | { | |
576 | /* We can't insert breakpoints until the child has | |
577 | finished with the shared memory region. We need to | |
578 | wait until that happens. Ideal would be to just | |
579 | call: | |
580 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
581 | - waitpid (parent_pid, &status, __WALL); | |
582 | However, most architectures can't handle a syscall | |
583 | being traced on the way out if it wasn't traced on | |
584 | the way in. | |
585 | ||
586 | We might also think to loop, continuing the child | |
587 | until it exits or gets a SIGTRAP. One problem is | |
588 | that the child might call ptrace with PTRACE_TRACEME. | |
589 | ||
590 | There's no simple and reliable way to figure out when | |
591 | the vforked child will be done with its copy of the | |
592 | shared memory. We could step it out of the syscall, | |
593 | two instructions, let it go, and then single-step the | |
594 | parent once. When we have hardware single-step, this | |
595 | would work; with software single-step it could still | |
596 | be made to work but we'd have to be able to insert | |
597 | single-step breakpoints in the child, and we'd have | |
598 | to insert -just- the single-step breakpoint in the | |
599 | parent. Very awkward. | |
600 | ||
601 | In the end, the best we can do is to make sure it | |
602 | runs for a little while. Hopefully it will be out of | |
603 | range of any breakpoints we reinsert. Usually this | |
604 | is only the single-step breakpoint at vfork's return | |
605 | point. */ | |
606 | ||
6c95b8df PA |
607 | if (debug_linux_nat) |
608 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
609 | "LCFF: no VFORK_DONE " |
610 | "support, sleeping a bit\n"); | |
6c95b8df | 611 | |
9016a515 | 612 | usleep (10000); |
9016a515 | 613 | |
6c95b8df PA |
614 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
615 | and leave it pending. The next linux_nat_resume call | |
616 | will notice a pending event, and bypasses actually | |
617 | resuming the inferior. */ | |
3ced3da4 PA |
618 | parent_lp->status = 0; |
619 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
620 | parent_lp->stopped = 1; | |
6c95b8df PA |
621 | |
622 | /* If we're in async mode, need to tell the event loop | |
623 | there's something here to process. */ | |
624 | if (target_can_async_p ()) | |
625 | async_file_mark (); | |
626 | } | |
9016a515 | 627 | } |
4de4c07c | 628 | } |
3993f6b1 | 629 | else |
4de4c07c | 630 | { |
77435e4c | 631 | struct inferior *parent_inf, *child_inf; |
3ced3da4 | 632 | struct lwp_info *child_lp; |
6c95b8df | 633 | struct program_space *parent_pspace; |
4de4c07c | 634 | |
e85a822c | 635 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
636 | { |
637 | target_terminal_ours (); | |
6c95b8df | 638 | if (has_vforked) |
3e43a32a MS |
639 | fprintf_filtered (gdb_stdlog, |
640 | _("Attaching after process %d " | |
641 | "vfork to child process %d.\n"), | |
6c95b8df PA |
642 | parent_pid, child_pid); |
643 | else | |
3e43a32a MS |
644 | fprintf_filtered (gdb_stdlog, |
645 | _("Attaching after process %d " | |
646 | "fork to child process %d.\n"), | |
6c95b8df | 647 | parent_pid, child_pid); |
f75c00e4 | 648 | } |
4de4c07c | 649 | |
7a7d3353 PA |
650 | /* Add the new inferior first, so that the target_detach below |
651 | doesn't unpush the target. */ | |
652 | ||
77435e4c PA |
653 | child_inf = add_inferior (child_pid); |
654 | ||
e58b0e63 | 655 | parent_inf = current_inferior (); |
77435e4c | 656 | child_inf->attach_flag = parent_inf->attach_flag; |
191c4426 | 657 | copy_terminal_info (child_inf, parent_inf); |
6ecd4729 PA |
658 | child_inf->gdbarch = parent_inf->gdbarch; |
659 | copy_inferior_target_desc_info (child_inf, parent_inf); | |
7a7d3353 | 660 | |
6c95b8df | 661 | parent_pspace = parent_inf->pspace; |
9016a515 | 662 | |
6c95b8df PA |
663 | /* If we're vforking, we want to hold on to the parent until the |
664 | child exits or execs. At child exec or exit time we can | |
665 | remove the old breakpoints from the parent and detach or | |
666 | resume debugging it. Otherwise, detach the parent now; we'll | |
667 | want to reuse it's program/address spaces, but we can't set | |
668 | them to the child before removing breakpoints from the | |
669 | parent, otherwise, the breakpoints module could decide to | |
670 | remove breakpoints from the wrong process (since they'd be | |
671 | assigned to the same address space). */ | |
9016a515 DJ |
672 | |
673 | if (has_vforked) | |
7f9f62ba | 674 | { |
6c95b8df PA |
675 | gdb_assert (child_inf->vfork_parent == NULL); |
676 | gdb_assert (parent_inf->vfork_child == NULL); | |
677 | child_inf->vfork_parent = parent_inf; | |
678 | child_inf->pending_detach = 0; | |
679 | parent_inf->vfork_child = child_inf; | |
680 | parent_inf->pending_detach = detach_fork; | |
681 | parent_inf->waiting_for_vfork_done = 0; | |
ac264b3b | 682 | } |
2277426b | 683 | else if (detach_fork) |
b84876c2 | 684 | target_detach (NULL, 0); |
4de4c07c | 685 | |
6c95b8df PA |
686 | /* Note that the detach above makes PARENT_INF dangling. */ |
687 | ||
688 | /* Add the child thread to the appropriate lists, and switch to | |
689 | this new thread, before cloning the program space, and | |
690 | informing the solib layer about this new process. */ | |
691 | ||
9f0bdab8 | 692 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
2277426b | 693 | add_thread (inferior_ptid); |
3ced3da4 PA |
694 | child_lp = add_lwp (inferior_ptid); |
695 | child_lp->stopped = 1; | |
25289eb2 | 696 | child_lp->last_resume_kind = resume_stop; |
6c95b8df PA |
697 | |
698 | /* If this is a vfork child, then the address-space is shared | |
699 | with the parent. If we detached from the parent, then we can | |
700 | reuse the parent's program/address spaces. */ | |
701 | if (has_vforked || detach_fork) | |
702 | { | |
703 | child_inf->pspace = parent_pspace; | |
704 | child_inf->aspace = child_inf->pspace->aspace; | |
705 | } | |
706 | else | |
707 | { | |
708 | child_inf->aspace = new_address_space (); | |
709 | child_inf->pspace = add_program_space (child_inf->aspace); | |
710 | child_inf->removable = 1; | |
7dcd53a0 | 711 | child_inf->symfile_flags = SYMFILE_NO_READ; |
6c95b8df PA |
712 | set_current_program_space (child_inf->pspace); |
713 | clone_program_space (child_inf->pspace, parent_pspace); | |
714 | ||
715 | /* Let the shared library layer (solib-svr4) learn about | |
716 | this new process, relocate the cloned exec, pull in | |
717 | shared libraries, and install the solib event breakpoint. | |
718 | If a "cloned-VM" event was propagated better throughout | |
719 | the core, this wouldn't be required. */ | |
268a4a75 | 720 | solib_create_inferior_hook (0); |
6c95b8df | 721 | } |
ac264b3b | 722 | |
6c95b8df | 723 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 724 | check_for_thread_db (); |
4de4c07c DJ |
725 | } |
726 | ||
727 | return 0; | |
728 | } | |
729 | ||
4de4c07c | 730 | \f |
77b06cd7 | 731 | static int |
a863b201 | 732 | linux_child_insert_fork_catchpoint (struct target_ops *self, int pid) |
4de4c07c | 733 | { |
96d7229d | 734 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
735 | } |
736 | ||
eb73ad13 | 737 | static int |
973fc227 | 738 | linux_child_remove_fork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
739 | { |
740 | return 0; | |
741 | } | |
742 | ||
77b06cd7 | 743 | static int |
3ecc7da0 | 744 | linux_child_insert_vfork_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 745 | { |
96d7229d | 746 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
747 | } |
748 | ||
eb73ad13 | 749 | static int |
e98cf0cd | 750 | linux_child_remove_vfork_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
751 | { |
752 | return 0; | |
753 | } | |
754 | ||
77b06cd7 | 755 | static int |
ba025e51 | 756 | linux_child_insert_exec_catchpoint (struct target_ops *self, int pid) |
3993f6b1 | 757 | { |
96d7229d | 758 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
759 | } |
760 | ||
eb73ad13 | 761 | static int |
758e29d2 | 762 | linux_child_remove_exec_catchpoint (struct target_ops *self, int pid) |
eb73ad13 PA |
763 | { |
764 | return 0; | |
765 | } | |
766 | ||
a96d9b2e | 767 | static int |
ff214e67 TT |
768 | linux_child_set_syscall_catchpoint (struct target_ops *self, |
769 | int pid, int needed, int any_count, | |
a96d9b2e SDJ |
770 | int table_size, int *table) |
771 | { | |
96d7229d | 772 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
773 | return 1; |
774 | ||
a96d9b2e SDJ |
775 | /* On GNU/Linux, we ignore the arguments. It means that we only |
776 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 777 | |
a96d9b2e SDJ |
778 | Also, we do not use the `table' information because we do not |
779 | filter system calls here. We let GDB do the logic for us. */ | |
780 | return 0; | |
781 | } | |
782 | ||
d6b0e80f AC |
783 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
784 | are processes sharing the same VM space. A multi-threaded process | |
785 | is basically a group of such processes. However, such a grouping | |
786 | is almost entirely a user-space issue; the kernel doesn't enforce | |
787 | such a grouping at all (this might change in the future). In | |
788 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
789 | Threads library) to provide such a grouping. | |
790 | ||
791 | It is perfectly well possible to write a multi-threaded application | |
792 | without the assistance of a threads library, by using the clone | |
793 | system call directly. This module should be able to give some | |
794 | rudimentary support for debugging such applications if developers | |
795 | specify the CLONE_PTRACE flag in the clone system call, and are | |
796 | using the Linux kernel 2.4 or above. | |
797 | ||
798 | Note that there are some peculiarities in GNU/Linux that affect | |
799 | this code: | |
800 | ||
801 | - In general one should specify the __WCLONE flag to waitpid in | |
802 | order to make it report events for any of the cloned processes | |
803 | (and leave it out for the initial process). However, if a cloned | |
804 | process has exited the exit status is only reported if the | |
805 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
806 | we cannot use it since GDB must work on older systems too. | |
807 | ||
808 | - When a traced, cloned process exits and is waited for by the | |
809 | debugger, the kernel reassigns it to the original parent and | |
810 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
811 | library doesn't notice this, which leads to the "zombie problem": | |
812 | When debugged a multi-threaded process that spawns a lot of | |
813 | threads will run out of processes, even if the threads exit, | |
814 | because the "zombies" stay around. */ | |
815 | ||
816 | /* List of known LWPs. */ | |
9f0bdab8 | 817 | struct lwp_info *lwp_list; |
d6b0e80f AC |
818 | \f |
819 | ||
d6b0e80f AC |
820 | /* Original signal mask. */ |
821 | static sigset_t normal_mask; | |
822 | ||
823 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
824 | _initialize_linux_nat. */ | |
825 | static sigset_t suspend_mask; | |
826 | ||
7feb7d06 PA |
827 | /* Signals to block to make that sigsuspend work. */ |
828 | static sigset_t blocked_mask; | |
829 | ||
830 | /* SIGCHLD action. */ | |
831 | struct sigaction sigchld_action; | |
b84876c2 | 832 | |
7feb7d06 PA |
833 | /* Block child signals (SIGCHLD and linux threads signals), and store |
834 | the previous mask in PREV_MASK. */ | |
84e46146 | 835 | |
7feb7d06 PA |
836 | static void |
837 | block_child_signals (sigset_t *prev_mask) | |
838 | { | |
839 | /* Make sure SIGCHLD is blocked. */ | |
840 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
841 | sigaddset (&blocked_mask, SIGCHLD); | |
842 | ||
843 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
844 | } | |
845 | ||
846 | /* Restore child signals mask, previously returned by | |
847 | block_child_signals. */ | |
848 | ||
849 | static void | |
850 | restore_child_signals_mask (sigset_t *prev_mask) | |
851 | { | |
852 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
853 | } | |
2455069d UW |
854 | |
855 | /* Mask of signals to pass directly to the inferior. */ | |
856 | static sigset_t pass_mask; | |
857 | ||
858 | /* Update signals to pass to the inferior. */ | |
859 | static void | |
94bedb42 TT |
860 | linux_nat_pass_signals (struct target_ops *self, |
861 | int numsigs, unsigned char *pass_signals) | |
2455069d UW |
862 | { |
863 | int signo; | |
864 | ||
865 | sigemptyset (&pass_mask); | |
866 | ||
867 | for (signo = 1; signo < NSIG; signo++) | |
868 | { | |
2ea28649 | 869 | int target_signo = gdb_signal_from_host (signo); |
2455069d UW |
870 | if (target_signo < numsigs && pass_signals[target_signo]) |
871 | sigaddset (&pass_mask, signo); | |
872 | } | |
873 | } | |
874 | ||
d6b0e80f AC |
875 | \f |
876 | ||
877 | /* Prototypes for local functions. */ | |
878 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
28439f5e | 879 | static int linux_thread_alive (ptid_t ptid); |
8dd27370 | 880 | static char *linux_child_pid_to_exec_file (struct target_ops *self, int pid); |
710151dd | 881 | |
d6b0e80f | 882 | \f |
d6b0e80f | 883 | |
7b50312a PA |
884 | /* Destroy and free LP. */ |
885 | ||
886 | static void | |
887 | lwp_free (struct lwp_info *lp) | |
888 | { | |
889 | xfree (lp->arch_private); | |
890 | xfree (lp); | |
891 | } | |
892 | ||
d90e17a7 PA |
893 | /* Remove all LWPs belong to PID from the lwp list. */ |
894 | ||
895 | static void | |
896 | purge_lwp_list (int pid) | |
897 | { | |
898 | struct lwp_info *lp, *lpprev, *lpnext; | |
899 | ||
900 | lpprev = NULL; | |
901 | ||
902 | for (lp = lwp_list; lp; lp = lpnext) | |
903 | { | |
904 | lpnext = lp->next; | |
905 | ||
906 | if (ptid_get_pid (lp->ptid) == pid) | |
907 | { | |
908 | if (lp == lwp_list) | |
909 | lwp_list = lp->next; | |
910 | else | |
911 | lpprev->next = lp->next; | |
912 | ||
7b50312a | 913 | lwp_free (lp); |
d90e17a7 PA |
914 | } |
915 | else | |
916 | lpprev = lp; | |
917 | } | |
918 | } | |
919 | ||
26cb8b7c PA |
920 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
921 | in the process. Return a pointer to the structure describing the | |
922 | new LWP. | |
923 | ||
924 | This differs from add_lwp in that we don't let the arch specific | |
925 | bits know about this new thread. Current clients of this callback | |
926 | take the opportunity to install watchpoints in the new thread, and | |
927 | we shouldn't do that for the first thread. If we're spawning a | |
928 | child ("run"), the thread executes the shell wrapper first, and we | |
929 | shouldn't touch it until it execs the program we want to debug. | |
930 | For "attach", it'd be okay to call the callback, but it's not | |
931 | necessary, because watchpoints can't yet have been inserted into | |
932 | the inferior. */ | |
d6b0e80f AC |
933 | |
934 | static struct lwp_info * | |
26cb8b7c | 935 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
936 | { |
937 | struct lwp_info *lp; | |
938 | ||
dfd4cc63 | 939 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f AC |
940 | |
941 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
942 | ||
943 | memset (lp, 0, sizeof (struct lwp_info)); | |
944 | ||
25289eb2 | 945 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
946 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
947 | ||
948 | lp->ptid = ptid; | |
dc146f7c | 949 | lp->core = -1; |
d6b0e80f AC |
950 | |
951 | lp->next = lwp_list; | |
952 | lwp_list = lp; | |
d6b0e80f | 953 | |
26cb8b7c PA |
954 | return lp; |
955 | } | |
956 | ||
957 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
958 | structure describing the new LWP. The LWP should already be | |
959 | stopped. */ | |
960 | ||
961 | static struct lwp_info * | |
962 | add_lwp (ptid_t ptid) | |
963 | { | |
964 | struct lwp_info *lp; | |
965 | ||
966 | lp = add_initial_lwp (ptid); | |
967 | ||
6e012a6c PA |
968 | /* Let the arch specific bits know about this new thread. Current |
969 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
970 | watchpoints in the new thread. We don't do this for the first |
971 | thread though. See add_initial_lwp. */ | |
972 | if (linux_nat_new_thread != NULL) | |
7b50312a | 973 | linux_nat_new_thread (lp); |
9f0bdab8 | 974 | |
d6b0e80f AC |
975 | return lp; |
976 | } | |
977 | ||
978 | /* Remove the LWP specified by PID from the list. */ | |
979 | ||
980 | static void | |
981 | delete_lwp (ptid_t ptid) | |
982 | { | |
983 | struct lwp_info *lp, *lpprev; | |
984 | ||
985 | lpprev = NULL; | |
986 | ||
987 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
988 | if (ptid_equal (lp->ptid, ptid)) | |
989 | break; | |
990 | ||
991 | if (!lp) | |
992 | return; | |
993 | ||
d6b0e80f AC |
994 | if (lpprev) |
995 | lpprev->next = lp->next; | |
996 | else | |
997 | lwp_list = lp->next; | |
998 | ||
7b50312a | 999 | lwp_free (lp); |
d6b0e80f AC |
1000 | } |
1001 | ||
1002 | /* Return a pointer to the structure describing the LWP corresponding | |
1003 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1004 | ||
1005 | static struct lwp_info * | |
1006 | find_lwp_pid (ptid_t ptid) | |
1007 | { | |
1008 | struct lwp_info *lp; | |
1009 | int lwp; | |
1010 | ||
dfd4cc63 LM |
1011 | if (ptid_lwp_p (ptid)) |
1012 | lwp = ptid_get_lwp (ptid); | |
d6b0e80f | 1013 | else |
dfd4cc63 | 1014 | lwp = ptid_get_pid (ptid); |
d6b0e80f AC |
1015 | |
1016 | for (lp = lwp_list; lp; lp = lp->next) | |
dfd4cc63 | 1017 | if (lwp == ptid_get_lwp (lp->ptid)) |
d6b0e80f AC |
1018 | return lp; |
1019 | ||
1020 | return NULL; | |
1021 | } | |
1022 | ||
1023 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1024 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1025 | pointer to the structure describing that LWP immediately. | |
1026 | Otherwise return NULL. */ | |
1027 | ||
1028 | struct lwp_info * | |
d90e17a7 PA |
1029 | iterate_over_lwps (ptid_t filter, |
1030 | int (*callback) (struct lwp_info *, void *), | |
1031 | void *data) | |
d6b0e80f AC |
1032 | { |
1033 | struct lwp_info *lp, *lpnext; | |
1034 | ||
1035 | for (lp = lwp_list; lp; lp = lpnext) | |
1036 | { | |
1037 | lpnext = lp->next; | |
d90e17a7 PA |
1038 | |
1039 | if (ptid_match (lp->ptid, filter)) | |
1040 | { | |
1041 | if ((*callback) (lp, data)) | |
1042 | return lp; | |
1043 | } | |
d6b0e80f AC |
1044 | } |
1045 | ||
1046 | return NULL; | |
1047 | } | |
1048 | ||
2277426b PA |
1049 | /* Update our internal state when changing from one checkpoint to |
1050 | another indicated by NEW_PTID. We can only switch single-threaded | |
1051 | applications, so we only create one new LWP, and the previous list | |
1052 | is discarded. */ | |
f973ed9c DJ |
1053 | |
1054 | void | |
1055 | linux_nat_switch_fork (ptid_t new_ptid) | |
1056 | { | |
1057 | struct lwp_info *lp; | |
1058 | ||
dfd4cc63 | 1059 | purge_lwp_list (ptid_get_pid (inferior_ptid)); |
2277426b | 1060 | |
f973ed9c DJ |
1061 | lp = add_lwp (new_ptid); |
1062 | lp->stopped = 1; | |
e26af52f | 1063 | |
2277426b PA |
1064 | /* This changes the thread's ptid while preserving the gdb thread |
1065 | num. Also changes the inferior pid, while preserving the | |
1066 | inferior num. */ | |
1067 | thread_change_ptid (inferior_ptid, new_ptid); | |
1068 | ||
1069 | /* We've just told GDB core that the thread changed target id, but, | |
1070 | in fact, it really is a different thread, with different register | |
1071 | contents. */ | |
1072 | registers_changed (); | |
e26af52f DJ |
1073 | } |
1074 | ||
e26af52f DJ |
1075 | /* Handle the exit of a single thread LP. */ |
1076 | ||
1077 | static void | |
1078 | exit_lwp (struct lwp_info *lp) | |
1079 | { | |
e09875d4 | 1080 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1081 | |
1082 | if (th) | |
e26af52f | 1083 | { |
17faa917 DJ |
1084 | if (print_thread_events) |
1085 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1086 | ||
4f8d22e3 | 1087 | delete_thread (lp->ptid); |
e26af52f DJ |
1088 | } |
1089 | ||
1090 | delete_lwp (lp->ptid); | |
1091 | } | |
1092 | ||
a0ef4274 DJ |
1093 | /* Wait for the LWP specified by LP, which we have just attached to. |
1094 | Returns a wait status for that LWP, to cache. */ | |
1095 | ||
1096 | static int | |
1097 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1098 | int *signalled) | |
1099 | { | |
dfd4cc63 | 1100 | pid_t new_pid, pid = ptid_get_lwp (ptid); |
a0ef4274 DJ |
1101 | int status; |
1102 | ||
644cebc9 | 1103 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1104 | { |
1105 | if (debug_linux_nat) | |
1106 | fprintf_unfiltered (gdb_stdlog, | |
1107 | "LNPAW: Attaching to a stopped process\n"); | |
1108 | ||
1109 | /* The process is definitely stopped. It is in a job control | |
1110 | stop, unless the kernel predates the TASK_STOPPED / | |
1111 | TASK_TRACED distinction, in which case it might be in a | |
1112 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1113 | can kill it, signal it, et cetera. | |
1114 | ||
1115 | First make sure there is a pending SIGSTOP. Since we are | |
1116 | already attached, the process can not transition from stopped | |
1117 | to running without a PTRACE_CONT; so we know this signal will | |
1118 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1119 | probably already in the queue (unless this kernel is old | |
1120 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1121 | is not an RT signal, it can only be queued once. */ | |
1122 | kill_lwp (pid, SIGSTOP); | |
1123 | ||
1124 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1125 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1126 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1127 | } | |
1128 | ||
1129 | /* Make sure the initial process is stopped. The user-level threads | |
1130 | layer might want to poke around in the inferior, and that won't | |
1131 | work if things haven't stabilized yet. */ | |
1132 | new_pid = my_waitpid (pid, &status, 0); | |
1133 | if (new_pid == -1 && errno == ECHILD) | |
1134 | { | |
1135 | if (first) | |
1136 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1137 | ||
1138 | /* Try again with __WCLONE to check cloned processes. */ | |
1139 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1140 | *cloned = 1; | |
1141 | } | |
1142 | ||
dacc9cb2 PP |
1143 | gdb_assert (pid == new_pid); |
1144 | ||
1145 | if (!WIFSTOPPED (status)) | |
1146 | { | |
1147 | /* The pid we tried to attach has apparently just exited. */ | |
1148 | if (debug_linux_nat) | |
1149 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1150 | pid, status_to_str (status)); | |
1151 | return status; | |
1152 | } | |
a0ef4274 DJ |
1153 | |
1154 | if (WSTOPSIG (status) != SIGSTOP) | |
1155 | { | |
1156 | *signalled = 1; | |
1157 | if (debug_linux_nat) | |
1158 | fprintf_unfiltered (gdb_stdlog, | |
1159 | "LNPAW: Received %s after attaching\n", | |
1160 | status_to_str (status)); | |
1161 | } | |
1162 | ||
1163 | return status; | |
1164 | } | |
1165 | ||
84636d28 PA |
1166 | /* Attach to the LWP specified by PID. Return 0 if successful, -1 if |
1167 | the new LWP could not be attached, or 1 if we're already auto | |
1168 | attached to this thread, but haven't processed the | |
1169 | PTRACE_EVENT_CLONE event of its parent thread, so we just ignore | |
1170 | its existance, without considering it an error. */ | |
d6b0e80f | 1171 | |
9ee57c33 | 1172 | int |
93815fbf | 1173 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1174 | { |
9ee57c33 | 1175 | struct lwp_info *lp; |
84636d28 | 1176 | int lwpid; |
d6b0e80f | 1177 | |
dfd4cc63 | 1178 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 1179 | |
9ee57c33 | 1180 | lp = find_lwp_pid (ptid); |
dfd4cc63 | 1181 | lwpid = ptid_get_lwp (ptid); |
d6b0e80f AC |
1182 | |
1183 | /* We assume that we're already attached to any LWP that has an id | |
1184 | equal to the overall process id, and to any LWP that is already | |
1185 | in our list of LWPs. If we're not seeing exit events from threads | |
1186 | and we've had PID wraparound since we last tried to stop all threads, | |
1187 | this assumption might be wrong; fortunately, this is very unlikely | |
1188 | to happen. */ | |
dfd4cc63 | 1189 | if (lwpid != ptid_get_pid (ptid) && lp == NULL) |
d6b0e80f | 1190 | { |
a0ef4274 | 1191 | int status, cloned = 0, signalled = 0; |
d6b0e80f | 1192 | |
84636d28 | 1193 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) |
9ee57c33 | 1194 | { |
96d7229d | 1195 | if (linux_supports_tracefork ()) |
84636d28 PA |
1196 | { |
1197 | /* If we haven't stopped all threads when we get here, | |
1198 | we may have seen a thread listed in thread_db's list, | |
1199 | but not processed the PTRACE_EVENT_CLONE yet. If | |
1200 | that's the case, ignore this new thread, and let | |
1201 | normal event handling discover it later. */ | |
1202 | if (in_pid_list_p (stopped_pids, lwpid)) | |
1203 | { | |
1204 | /* We've already seen this thread stop, but we | |
1205 | haven't seen the PTRACE_EVENT_CLONE extended | |
1206 | event yet. */ | |
84636d28 PA |
1207 | return 0; |
1208 | } | |
1209 | else | |
1210 | { | |
1211 | int new_pid; | |
1212 | int status; | |
1213 | ||
1214 | /* See if we've got a stop for this new child | |
1215 | pending. If so, we're already attached. */ | |
1216 | new_pid = my_waitpid (lwpid, &status, WNOHANG); | |
1217 | if (new_pid == -1 && errno == ECHILD) | |
1218 | new_pid = my_waitpid (lwpid, &status, __WCLONE | WNOHANG); | |
1219 | if (new_pid != -1) | |
1220 | { | |
1221 | if (WIFSTOPPED (status)) | |
1222 | add_to_pid_list (&stopped_pids, lwpid, status); | |
84636d28 PA |
1223 | return 1; |
1224 | } | |
1225 | } | |
1226 | } | |
1227 | ||
9ee57c33 DJ |
1228 | /* If we fail to attach to the thread, issue a warning, |
1229 | but continue. One way this can happen is if thread | |
e9efe249 | 1230 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1231 | bug may place threads in the thread list and then fail |
1232 | to create them. */ | |
1233 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1234 | safe_strerror (errno)); | |
1235 | return -1; | |
1236 | } | |
1237 | ||
d6b0e80f AC |
1238 | if (debug_linux_nat) |
1239 | fprintf_unfiltered (gdb_stdlog, | |
1240 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1241 | target_pid_to_str (ptid)); | |
1242 | ||
a0ef4274 | 1243 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
dacc9cb2 | 1244 | if (!WIFSTOPPED (status)) |
12696c10 | 1245 | return 1; |
dacc9cb2 | 1246 | |
a0ef4274 DJ |
1247 | lp = add_lwp (ptid); |
1248 | lp->stopped = 1; | |
1249 | lp->cloned = cloned; | |
1250 | lp->signalled = signalled; | |
1251 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1252 | { |
a0ef4274 DJ |
1253 | lp->resumed = 1; |
1254 | lp->status = status; | |
d6b0e80f AC |
1255 | } |
1256 | ||
dfd4cc63 | 1257 | target_post_attach (ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
1258 | |
1259 | if (debug_linux_nat) | |
1260 | { | |
1261 | fprintf_unfiltered (gdb_stdlog, | |
1262 | "LLAL: waitpid %s received %s\n", | |
1263 | target_pid_to_str (ptid), | |
1264 | status_to_str (status)); | |
1265 | } | |
1266 | } | |
1267 | else | |
1268 | { | |
1269 | /* We assume that the LWP representing the original process is | |
1270 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1271 | that the GNU/linux ptrace layer uses to keep track of |
1272 | threads. Note that this won't have already been done since | |
1273 | the main thread will have, we assume, been stopped by an | |
1274 | attach from a different layer. */ | |
9ee57c33 DJ |
1275 | if (lp == NULL) |
1276 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1277 | lp->stopped = 1; |
1278 | } | |
9ee57c33 | 1279 | |
25289eb2 | 1280 | lp->last_resume_kind = resume_stop; |
9ee57c33 | 1281 | return 0; |
d6b0e80f AC |
1282 | } |
1283 | ||
b84876c2 | 1284 | static void |
136d6dae VP |
1285 | linux_nat_create_inferior (struct target_ops *ops, |
1286 | char *exec_file, char *allargs, char **env, | |
b84876c2 PA |
1287 | int from_tty) |
1288 | { | |
10568435 JK |
1289 | #ifdef HAVE_PERSONALITY |
1290 | int personality_orig = 0, personality_set = 0; | |
1291 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1292 | |
1293 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1294 | we have to mask the async mode. */ | |
1295 | ||
10568435 JK |
1296 | #ifdef HAVE_PERSONALITY |
1297 | if (disable_randomization) | |
1298 | { | |
1299 | errno = 0; | |
1300 | personality_orig = personality (0xffffffff); | |
1301 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1302 | { | |
1303 | personality_set = 1; | |
1304 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1305 | } | |
1306 | if (errno != 0 || (personality_set | |
1307 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1308 | warning (_("Error disabling address space randomization: %s"), | |
1309 | safe_strerror (errno)); | |
1310 | } | |
1311 | #endif /* HAVE_PERSONALITY */ | |
1312 | ||
2455069d | 1313 | /* Make sure we report all signals during startup. */ |
94bedb42 | 1314 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1315 | |
136d6dae | 1316 | linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty); |
b84876c2 | 1317 | |
10568435 JK |
1318 | #ifdef HAVE_PERSONALITY |
1319 | if (personality_set) | |
1320 | { | |
1321 | errno = 0; | |
1322 | personality (personality_orig); | |
1323 | if (errno != 0) | |
1324 | warning (_("Error restoring address space randomization: %s"), | |
1325 | safe_strerror (errno)); | |
1326 | } | |
1327 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1328 | } |
1329 | ||
d6b0e80f | 1330 | static void |
c0939df1 | 1331 | linux_nat_attach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f AC |
1332 | { |
1333 | struct lwp_info *lp; | |
d6b0e80f | 1334 | int status; |
af990527 | 1335 | ptid_t ptid; |
87b0bb13 | 1336 | volatile struct gdb_exception ex; |
d6b0e80f | 1337 | |
2455069d | 1338 | /* Make sure we report all signals during attach. */ |
94bedb42 | 1339 | linux_nat_pass_signals (ops, 0, NULL); |
2455069d | 1340 | |
87b0bb13 JK |
1341 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
1342 | { | |
1343 | linux_ops->to_attach (ops, args, from_tty); | |
1344 | } | |
1345 | if (ex.reason < 0) | |
1346 | { | |
1347 | pid_t pid = parse_pid_to_attach (args); | |
1348 | struct buffer buffer; | |
1349 | char *message, *buffer_s; | |
1350 | ||
1351 | message = xstrdup (ex.message); | |
1352 | make_cleanup (xfree, message); | |
1353 | ||
1354 | buffer_init (&buffer); | |
7ae1a6a6 | 1355 | linux_ptrace_attach_fail_reason (pid, &buffer); |
87b0bb13 JK |
1356 | |
1357 | buffer_grow_str0 (&buffer, ""); | |
1358 | buffer_s = buffer_finish (&buffer); | |
1359 | make_cleanup (xfree, buffer_s); | |
1360 | ||
7ae1a6a6 PA |
1361 | if (*buffer_s != '\0') |
1362 | throw_error (ex.error, "warning: %s\n%s", buffer_s, message); | |
1363 | else | |
1364 | throw_error (ex.error, "%s", message); | |
87b0bb13 | 1365 | } |
d6b0e80f | 1366 | |
af990527 PA |
1367 | /* The ptrace base target adds the main thread with (pid,0,0) |
1368 | format. Decorate it with lwp info. */ | |
dfd4cc63 LM |
1369 | ptid = ptid_build (ptid_get_pid (inferior_ptid), |
1370 | ptid_get_pid (inferior_ptid), | |
1371 | 0); | |
af990527 PA |
1372 | thread_change_ptid (inferior_ptid, ptid); |
1373 | ||
9f0bdab8 | 1374 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1375 | lp = add_initial_lwp (ptid); |
a0ef4274 DJ |
1376 | |
1377 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1378 | &lp->signalled); | |
dacc9cb2 PP |
1379 | if (!WIFSTOPPED (status)) |
1380 | { | |
1381 | if (WIFEXITED (status)) | |
1382 | { | |
1383 | int exit_code = WEXITSTATUS (status); | |
1384 | ||
1385 | target_terminal_ours (); | |
1386 | target_mourn_inferior (); | |
1387 | if (exit_code == 0) | |
1388 | error (_("Unable to attach: program exited normally.")); | |
1389 | else | |
1390 | error (_("Unable to attach: program exited with code %d."), | |
1391 | exit_code); | |
1392 | } | |
1393 | else if (WIFSIGNALED (status)) | |
1394 | { | |
2ea28649 | 1395 | enum gdb_signal signo; |
dacc9cb2 PP |
1396 | |
1397 | target_terminal_ours (); | |
1398 | target_mourn_inferior (); | |
1399 | ||
2ea28649 | 1400 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1401 | error (_("Unable to attach: program terminated with signal " |
1402 | "%s, %s."), | |
2ea28649 PA |
1403 | gdb_signal_to_name (signo), |
1404 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1405 | } |
1406 | ||
1407 | internal_error (__FILE__, __LINE__, | |
1408 | _("unexpected status %d for PID %ld"), | |
dfd4cc63 | 1409 | status, (long) ptid_get_lwp (ptid)); |
dacc9cb2 PP |
1410 | } |
1411 | ||
a0ef4274 | 1412 | lp->stopped = 1; |
9f0bdab8 | 1413 | |
a0ef4274 | 1414 | /* Save the wait status to report later. */ |
d6b0e80f | 1415 | lp->resumed = 1; |
a0ef4274 DJ |
1416 | if (debug_linux_nat) |
1417 | fprintf_unfiltered (gdb_stdlog, | |
1418 | "LNA: waitpid %ld, saving status %s\n", | |
dfd4cc63 | 1419 | (long) ptid_get_pid (lp->ptid), status_to_str (status)); |
710151dd | 1420 | |
7feb7d06 PA |
1421 | lp->status = status; |
1422 | ||
1423 | if (target_can_async_p ()) | |
1424 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1425 | } |
1426 | ||
a0ef4274 DJ |
1427 | /* Get pending status of LP. */ |
1428 | static int | |
1429 | get_pending_status (struct lwp_info *lp, int *status) | |
1430 | { | |
a493e3e2 | 1431 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1432 | |
1433 | /* If we paused threads momentarily, we may have stored pending | |
1434 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1435 | and GDB core hasn't seen any signal for those threads. | |
1436 | Otherwise, the last signal reported to the core is found in the | |
1437 | thread object's stop_signal. | |
1438 | ||
1439 | There's a corner case that isn't handled here at present. Only | |
1440 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1441 | stop_signal make sense as a real signal to pass to the inferior. | |
1442 | Some catchpoint related events, like | |
1443 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1444 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1445 | those traps are debug API (ptrace in our case) related and |
1446 | induced; the inferior wouldn't see them if it wasn't being | |
1447 | traced. Hence, we should never pass them to the inferior, even | |
1448 | when set to pass state. Since this corner case isn't handled by | |
1449 | infrun.c when proceeding with a signal, for consistency, neither | |
1450 | do we handle it here (or elsewhere in the file we check for | |
1451 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1452 | this is really a corner case. */ | |
1453 | ||
1454 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1455 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1456 | else if (lp->status) |
2ea28649 | 1457 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
ca2163eb PA |
1458 | else if (non_stop && !is_executing (lp->ptid)) |
1459 | { | |
1460 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1461 | |
16c381f0 | 1462 | signo = tp->suspend.stop_signal; |
ca2163eb PA |
1463 | } |
1464 | else if (!non_stop) | |
a0ef4274 | 1465 | { |
ca2163eb PA |
1466 | struct target_waitstatus last; |
1467 | ptid_t last_ptid; | |
4c28f408 | 1468 | |
ca2163eb | 1469 | get_last_target_status (&last_ptid, &last); |
4c28f408 | 1470 | |
dfd4cc63 | 1471 | if (ptid_get_lwp (lp->ptid) == ptid_get_lwp (last_ptid)) |
ca2163eb | 1472 | { |
e09875d4 | 1473 | struct thread_info *tp = find_thread_ptid (lp->ptid); |
e0881a8e | 1474 | |
16c381f0 | 1475 | signo = tp->suspend.stop_signal; |
4c28f408 | 1476 | } |
ca2163eb | 1477 | } |
4c28f408 | 1478 | |
ca2163eb | 1479 | *status = 0; |
4c28f408 | 1480 | |
a493e3e2 | 1481 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1482 | { |
1483 | if (debug_linux_nat) | |
1484 | fprintf_unfiltered (gdb_stdlog, | |
1485 | "GPT: lwp %s has no pending signal\n", | |
1486 | target_pid_to_str (lp->ptid)); | |
1487 | } | |
1488 | else if (!signal_pass_state (signo)) | |
1489 | { | |
1490 | if (debug_linux_nat) | |
3e43a32a MS |
1491 | fprintf_unfiltered (gdb_stdlog, |
1492 | "GPT: lwp %s had signal %s, " | |
1493 | "but it is in no pass state\n", | |
ca2163eb | 1494 | target_pid_to_str (lp->ptid), |
2ea28649 | 1495 | gdb_signal_to_string (signo)); |
a0ef4274 | 1496 | } |
a0ef4274 | 1497 | else |
4c28f408 | 1498 | { |
2ea28649 | 1499 | *status = W_STOPCODE (gdb_signal_to_host (signo)); |
ca2163eb PA |
1500 | |
1501 | if (debug_linux_nat) | |
1502 | fprintf_unfiltered (gdb_stdlog, | |
1503 | "GPT: lwp %s has pending signal %s\n", | |
1504 | target_pid_to_str (lp->ptid), | |
2ea28649 | 1505 | gdb_signal_to_string (signo)); |
4c28f408 | 1506 | } |
a0ef4274 DJ |
1507 | |
1508 | return 0; | |
1509 | } | |
1510 | ||
d6b0e80f AC |
1511 | static int |
1512 | detach_callback (struct lwp_info *lp, void *data) | |
1513 | { | |
1514 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1515 | ||
1516 | if (debug_linux_nat && lp->status) | |
1517 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1518 | strsignal (WSTOPSIG (lp->status)), | |
1519 | target_pid_to_str (lp->ptid)); | |
1520 | ||
a0ef4274 DJ |
1521 | /* If there is a pending SIGSTOP, get rid of it. */ |
1522 | if (lp->signalled) | |
d6b0e80f | 1523 | { |
d6b0e80f AC |
1524 | if (debug_linux_nat) |
1525 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1526 | "DC: Sending SIGCONT to %s\n", |
1527 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1528 | |
dfd4cc63 | 1529 | kill_lwp (ptid_get_lwp (lp->ptid), SIGCONT); |
d6b0e80f | 1530 | lp->signalled = 0; |
d6b0e80f AC |
1531 | } |
1532 | ||
1533 | /* We don't actually detach from the LWP that has an id equal to the | |
1534 | overall process id just yet. */ | |
dfd4cc63 | 1535 | if (ptid_get_lwp (lp->ptid) != ptid_get_pid (lp->ptid)) |
d6b0e80f | 1536 | { |
a0ef4274 DJ |
1537 | int status = 0; |
1538 | ||
1539 | /* Pass on any pending signal for this LWP. */ | |
1540 | get_pending_status (lp, &status); | |
1541 | ||
7b50312a PA |
1542 | if (linux_nat_prepare_to_resume != NULL) |
1543 | linux_nat_prepare_to_resume (lp); | |
d6b0e80f | 1544 | errno = 0; |
dfd4cc63 | 1545 | if (ptrace (PTRACE_DETACH, ptid_get_lwp (lp->ptid), 0, |
a0ef4274 | 1546 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1547 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1548 | safe_strerror (errno)); |
1549 | ||
1550 | if (debug_linux_nat) | |
1551 | fprintf_unfiltered (gdb_stdlog, | |
1552 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1553 | target_pid_to_str (lp->ptid), | |
7feb7d06 | 1554 | strsignal (WSTOPSIG (status))); |
d6b0e80f AC |
1555 | |
1556 | delete_lwp (lp->ptid); | |
1557 | } | |
1558 | ||
1559 | return 0; | |
1560 | } | |
1561 | ||
1562 | static void | |
52554a0e | 1563 | linux_nat_detach (struct target_ops *ops, const char *args, int from_tty) |
d6b0e80f | 1564 | { |
b84876c2 | 1565 | int pid; |
a0ef4274 | 1566 | int status; |
d90e17a7 PA |
1567 | struct lwp_info *main_lwp; |
1568 | ||
dfd4cc63 | 1569 | pid = ptid_get_pid (inferior_ptid); |
a0ef4274 | 1570 | |
ae5e0686 MK |
1571 | /* Don't unregister from the event loop, as there may be other |
1572 | inferiors running. */ | |
b84876c2 | 1573 | |
4c28f408 PA |
1574 | /* Stop all threads before detaching. ptrace requires that the |
1575 | thread is stopped to sucessfully detach. */ | |
d90e17a7 | 1576 | iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL); |
4c28f408 PA |
1577 | /* ... and wait until all of them have reported back that |
1578 | they're no longer running. */ | |
d90e17a7 | 1579 | iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL); |
4c28f408 | 1580 | |
d90e17a7 | 1581 | iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL); |
d6b0e80f AC |
1582 | |
1583 | /* Only the initial process should be left right now. */ | |
dfd4cc63 | 1584 | gdb_assert (num_lwps (ptid_get_pid (inferior_ptid)) == 1); |
d90e17a7 PA |
1585 | |
1586 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
d6b0e80f | 1587 | |
a0ef4274 DJ |
1588 | /* Pass on any pending signal for the last LWP. */ |
1589 | if ((args == NULL || *args == '\0') | |
d90e17a7 | 1590 | && get_pending_status (main_lwp, &status) != -1 |
a0ef4274 DJ |
1591 | && WIFSTOPPED (status)) |
1592 | { | |
52554a0e TT |
1593 | char *tem; |
1594 | ||
a0ef4274 DJ |
1595 | /* Put the signal number in ARGS so that inf_ptrace_detach will |
1596 | pass it along with PTRACE_DETACH. */ | |
52554a0e | 1597 | tem = alloca (8); |
cde33bf1 | 1598 | xsnprintf (tem, 8, "%d", (int) WSTOPSIG (status)); |
52554a0e | 1599 | args = tem; |
ddabfc73 TT |
1600 | if (debug_linux_nat) |
1601 | fprintf_unfiltered (gdb_stdlog, | |
1602 | "LND: Sending signal %s to %s\n", | |
1603 | args, | |
1604 | target_pid_to_str (main_lwp->ptid)); | |
a0ef4274 DJ |
1605 | } |
1606 | ||
7b50312a PA |
1607 | if (linux_nat_prepare_to_resume != NULL) |
1608 | linux_nat_prepare_to_resume (main_lwp); | |
d90e17a7 | 1609 | delete_lwp (main_lwp->ptid); |
b84876c2 | 1610 | |
7a7d3353 PA |
1611 | if (forks_exist_p ()) |
1612 | { | |
1613 | /* Multi-fork case. The current inferior_ptid is being detached | |
1614 | from, but there are other viable forks to debug. Detach from | |
1615 | the current fork, and context-switch to the first | |
1616 | available. */ | |
1617 | linux_fork_detach (args, from_tty); | |
7a7d3353 PA |
1618 | } |
1619 | else | |
1620 | linux_ops->to_detach (ops, args, from_tty); | |
d6b0e80f AC |
1621 | } |
1622 | ||
1623 | /* Resume LP. */ | |
1624 | ||
25289eb2 | 1625 | static void |
e5ef252a | 1626 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1627 | { |
25289eb2 | 1628 | if (lp->stopped) |
6c95b8df | 1629 | { |
dfd4cc63 | 1630 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
25289eb2 PA |
1631 | |
1632 | if (inf->vfork_child != NULL) | |
1633 | { | |
1634 | if (debug_linux_nat) | |
1635 | fprintf_unfiltered (gdb_stdlog, | |
1636 | "RC: Not resuming %s (vfork parent)\n", | |
1637 | target_pid_to_str (lp->ptid)); | |
1638 | } | |
1639 | else if (lp->status == 0 | |
1640 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
1641 | { | |
1642 | if (debug_linux_nat) | |
1643 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a PA |
1644 | "RC: Resuming sibling %s, %s, %s\n", |
1645 | target_pid_to_str (lp->ptid), | |
1646 | (signo != GDB_SIGNAL_0 | |
1647 | ? strsignal (gdb_signal_to_host (signo)) | |
1648 | : "0"), | |
1649 | step ? "step" : "resume"); | |
25289eb2 | 1650 | |
7b50312a PA |
1651 | if (linux_nat_prepare_to_resume != NULL) |
1652 | linux_nat_prepare_to_resume (lp); | |
25289eb2 | 1653 | linux_ops->to_resume (linux_ops, |
dfd4cc63 | 1654 | pid_to_ptid (ptid_get_lwp (lp->ptid)), |
e5ef252a | 1655 | step, signo); |
25289eb2 PA |
1656 | lp->stopped = 0; |
1657 | lp->step = step; | |
25289eb2 PA |
1658 | lp->stopped_by_watchpoint = 0; |
1659 | } | |
1660 | else | |
1661 | { | |
1662 | if (debug_linux_nat) | |
1663 | fprintf_unfiltered (gdb_stdlog, | |
1664 | "RC: Not resuming sibling %s (has pending)\n", | |
1665 | target_pid_to_str (lp->ptid)); | |
1666 | } | |
6c95b8df | 1667 | } |
25289eb2 | 1668 | else |
d6b0e80f | 1669 | { |
d90e17a7 PA |
1670 | if (debug_linux_nat) |
1671 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1672 | "RC: Not resuming sibling %s (not stopped)\n", |
d6b0e80f | 1673 | target_pid_to_str (lp->ptid)); |
d6b0e80f | 1674 | } |
25289eb2 | 1675 | } |
d6b0e80f | 1676 | |
8817a6f2 PA |
1677 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1678 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1679 | |
25289eb2 | 1680 | static int |
8817a6f2 | 1681 | linux_nat_resume_callback (struct lwp_info *lp, void *except) |
25289eb2 | 1682 | { |
e5ef252a PA |
1683 | enum gdb_signal signo = GDB_SIGNAL_0; |
1684 | ||
8817a6f2 PA |
1685 | if (lp == except) |
1686 | return 0; | |
1687 | ||
e5ef252a PA |
1688 | if (lp->stopped) |
1689 | { | |
1690 | struct thread_info *thread; | |
1691 | ||
1692 | thread = find_thread_ptid (lp->ptid); | |
1693 | if (thread != NULL) | |
1694 | { | |
70509625 | 1695 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1696 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1697 | } | |
1698 | } | |
1699 | ||
1700 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1701 | return 0; |
1702 | } | |
1703 | ||
1704 | static int | |
1705 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1706 | { | |
1707 | lp->resumed = 0; | |
25289eb2 | 1708 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1709 | return 0; |
1710 | } | |
1711 | ||
1712 | static int | |
1713 | resume_set_callback (struct lwp_info *lp, void *data) | |
1714 | { | |
1715 | lp->resumed = 1; | |
25289eb2 | 1716 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1717 | return 0; |
1718 | } | |
1719 | ||
1720 | static void | |
28439f5e | 1721 | linux_nat_resume (struct target_ops *ops, |
2ea28649 | 1722 | ptid_t ptid, int step, enum gdb_signal signo) |
d6b0e80f AC |
1723 | { |
1724 | struct lwp_info *lp; | |
d90e17a7 | 1725 | int resume_many; |
d6b0e80f | 1726 | |
76f50ad1 DJ |
1727 | if (debug_linux_nat) |
1728 | fprintf_unfiltered (gdb_stdlog, | |
1729 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1730 | step ? "step" : "resume", | |
1731 | target_pid_to_str (ptid), | |
a493e3e2 | 1732 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1733 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
76f50ad1 DJ |
1734 | target_pid_to_str (inferior_ptid)); |
1735 | ||
d6b0e80f | 1736 | /* A specific PTID means `step only this process id'. */ |
d90e17a7 PA |
1737 | resume_many = (ptid_equal (minus_one_ptid, ptid) |
1738 | || ptid_is_pid (ptid)); | |
4c28f408 | 1739 | |
e3e9f5a2 PA |
1740 | /* Mark the lwps we're resuming as resumed. */ |
1741 | iterate_over_lwps (ptid, resume_set_callback, NULL); | |
d6b0e80f | 1742 | |
d90e17a7 PA |
1743 | /* See if it's the current inferior that should be handled |
1744 | specially. */ | |
1745 | if (resume_many) | |
1746 | lp = find_lwp_pid (inferior_ptid); | |
1747 | else | |
1748 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1749 | gdb_assert (lp != NULL); |
d6b0e80f | 1750 | |
9f0bdab8 DJ |
1751 | /* Remember if we're stepping. */ |
1752 | lp->step = step; | |
25289eb2 | 1753 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1754 | |
9f0bdab8 DJ |
1755 | /* If we have a pending wait status for this thread, there is no |
1756 | point in resuming the process. But first make sure that | |
1757 | linux_nat_wait won't preemptively handle the event - we | |
1758 | should never take this short-circuit if we are going to | |
1759 | leave LP running, since we have skipped resuming all the | |
1760 | other threads. This bit of code needs to be synchronized | |
1761 | with linux_nat_wait. */ | |
76f50ad1 | 1762 | |
9f0bdab8 DJ |
1763 | if (lp->status && WIFSTOPPED (lp->status)) |
1764 | { | |
2455069d UW |
1765 | if (!lp->step |
1766 | && WSTOPSIG (lp->status) | |
1767 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1768 | { |
9f0bdab8 DJ |
1769 | if (debug_linux_nat) |
1770 | fprintf_unfiltered (gdb_stdlog, | |
1771 | "LLR: Not short circuiting for ignored " | |
1772 | "status 0x%x\n", lp->status); | |
1773 | ||
d6b0e80f AC |
1774 | /* FIXME: What should we do if we are supposed to continue |
1775 | this thread with a signal? */ | |
a493e3e2 | 1776 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1777 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1778 | lp->status = 0; |
1779 | } | |
1780 | } | |
76f50ad1 | 1781 | |
6c95b8df | 1782 | if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) |
9f0bdab8 DJ |
1783 | { |
1784 | /* FIXME: What should we do if we are supposed to continue | |
1785 | this thread with a signal? */ | |
a493e3e2 | 1786 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1787 | |
9f0bdab8 DJ |
1788 | if (debug_linux_nat) |
1789 | fprintf_unfiltered (gdb_stdlog, | |
1790 | "LLR: Short circuiting for status 0x%x\n", | |
1791 | lp->status); | |
d6b0e80f | 1792 | |
7feb7d06 PA |
1793 | if (target_can_async_p ()) |
1794 | { | |
1795 | target_async (inferior_event_handler, 0); | |
1796 | /* Tell the event loop we have something to process. */ | |
1797 | async_file_mark (); | |
1798 | } | |
9f0bdab8 | 1799 | return; |
d6b0e80f AC |
1800 | } |
1801 | ||
d90e17a7 | 1802 | if (resume_many) |
8817a6f2 | 1803 | iterate_over_lwps (ptid, linux_nat_resume_callback, lp); |
d90e17a7 PA |
1804 | |
1805 | /* Convert to something the lower layer understands. */ | |
dfd4cc63 | 1806 | ptid = pid_to_ptid (ptid_get_lwp (lp->ptid)); |
d6b0e80f | 1807 | |
7b50312a PA |
1808 | if (linux_nat_prepare_to_resume != NULL) |
1809 | linux_nat_prepare_to_resume (lp); | |
28439f5e | 1810 | linux_ops->to_resume (linux_ops, ptid, step, signo); |
ebec9a0f | 1811 | lp->stopped_by_watchpoint = 0; |
8817a6f2 | 1812 | lp->stopped = 0; |
9f0bdab8 | 1813 | |
d6b0e80f AC |
1814 | if (debug_linux_nat) |
1815 | fprintf_unfiltered (gdb_stdlog, | |
1816 | "LLR: %s %s, %s (resume event thread)\n", | |
1817 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1818 | target_pid_to_str (ptid), | |
a493e3e2 | 1819 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1820 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 PA |
1821 | |
1822 | if (target_can_async_p ()) | |
8ea051c5 | 1823 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1824 | } |
1825 | ||
c5f62d5f | 1826 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1827 | |
1828 | static int | |
1829 | kill_lwp (int lwpid, int signo) | |
1830 | { | |
c5f62d5f DE |
1831 | /* Use tkill, if possible, in case we are using nptl threads. If tkill |
1832 | fails, then we are not using nptl threads and we should be using kill. */ | |
d6b0e80f AC |
1833 | |
1834 | #ifdef HAVE_TKILL_SYSCALL | |
c5f62d5f DE |
1835 | { |
1836 | static int tkill_failed; | |
1837 | ||
1838 | if (!tkill_failed) | |
1839 | { | |
1840 | int ret; | |
1841 | ||
1842 | errno = 0; | |
1843 | ret = syscall (__NR_tkill, lwpid, signo); | |
1844 | if (errno != ENOSYS) | |
1845 | return ret; | |
1846 | tkill_failed = 1; | |
1847 | } | |
1848 | } | |
d6b0e80f AC |
1849 | #endif |
1850 | ||
1851 | return kill (lwpid, signo); | |
1852 | } | |
1853 | ||
ca2163eb PA |
1854 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1855 | event, check if the core is interested in it: if not, ignore the | |
1856 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1857 | syscall entry/exit status, since the ptrace event itself doesn't | |
1858 | indicate it, and report the trap to higher layers. */ | |
1859 | ||
1860 | static int | |
1861 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1862 | { | |
1863 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1864 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
1865 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid); | |
1866 | ||
1867 | if (stopping) | |
1868 | { | |
1869 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1870 | makes it so that the LWP reports an immediate syscall return, | |
1871 | followed by the SIGSTOP. Skip seeing that "return" using | |
1872 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1873 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1874 | entry event. If we didn't do this (and returned 0), we'd | |
1875 | leave a syscall entry pending, and our caller, by using | |
1876 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1877 | itself. Later, when the user re-resumes this LWP, we'd see | |
1878 | another syscall entry event and we'd mistake it for a return. | |
1879 | ||
1880 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1881 | (leaving immediately with LWP->signalled set, without issuing | |
1882 | a PTRACE_CONT), it would still be problematic to leave this | |
1883 | syscall enter pending, as later when the thread is resumed, | |
1884 | it would then see the same syscall exit mentioned above, | |
1885 | followed by the delayed SIGSTOP, while the syscall didn't | |
1886 | actually get to execute. It seems it would be even more | |
1887 | confusing to the user. */ | |
1888 | ||
1889 | if (debug_linux_nat) | |
1890 | fprintf_unfiltered (gdb_stdlog, | |
1891 | "LHST: ignoring syscall %d " | |
1892 | "for LWP %ld (stopping threads), " | |
1893 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1894 | syscall_number, | |
dfd4cc63 | 1895 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1896 | |
1897 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
dfd4cc63 | 1898 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 1899 | lp->stopped = 0; |
ca2163eb PA |
1900 | return 1; |
1901 | } | |
1902 | ||
1903 | if (catch_syscall_enabled ()) | |
1904 | { | |
1905 | /* Always update the entry/return state, even if this particular | |
1906 | syscall isn't interesting to the core now. In async mode, | |
1907 | the user could install a new catchpoint for this syscall | |
1908 | between syscall enter/return, and we'll need to know to | |
1909 | report a syscall return if that happens. */ | |
1910 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1911 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1912 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1913 | ||
1914 | if (catching_syscall_number (syscall_number)) | |
1915 | { | |
1916 | /* Alright, an event to report. */ | |
1917 | ourstatus->kind = lp->syscall_state; | |
1918 | ourstatus->value.syscall_number = syscall_number; | |
1919 | ||
1920 | if (debug_linux_nat) | |
1921 | fprintf_unfiltered (gdb_stdlog, | |
1922 | "LHST: stopping for %s of syscall %d" | |
1923 | " for LWP %ld\n", | |
3e43a32a MS |
1924 | lp->syscall_state |
1925 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1926 | ? "entry" : "return", |
1927 | syscall_number, | |
dfd4cc63 | 1928 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1929 | return 0; |
1930 | } | |
1931 | ||
1932 | if (debug_linux_nat) | |
1933 | fprintf_unfiltered (gdb_stdlog, | |
1934 | "LHST: ignoring %s of syscall %d " | |
1935 | "for LWP %ld\n", | |
1936 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1937 | ? "entry" : "return", | |
1938 | syscall_number, | |
dfd4cc63 | 1939 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1940 | } |
1941 | else | |
1942 | { | |
1943 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1944 | before on this LWP, it could happen that the user removes all | |
1945 | syscall catchpoints before we get to process this event. | |
1946 | There are two noteworthy issues here: | |
1947 | ||
1948 | - When stopped at a syscall entry event, resuming with | |
1949 | PT_STEP still resumes executing the syscall and reports a | |
1950 | syscall return. | |
1951 | ||
1952 | - Only PT_SYSCALL catches syscall enters. If we last | |
1953 | single-stepped this thread, then this event can't be a | |
1954 | syscall enter. If we last single-stepped this thread, this | |
1955 | has to be a syscall exit. | |
1956 | ||
1957 | The points above mean that the next resume, be it PT_STEP or | |
1958 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1959 | if (debug_linux_nat) | |
1960 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1961 | "LHST: caught syscall event " |
1962 | "with no syscall catchpoints." | |
ca2163eb PA |
1963 | " %d for LWP %ld, ignoring\n", |
1964 | syscall_number, | |
dfd4cc63 | 1965 | ptid_get_lwp (lp->ptid)); |
ca2163eb PA |
1966 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1967 | } | |
1968 | ||
1969 | /* The core isn't interested in this event. For efficiency, avoid | |
1970 | stopping all threads only to have the core resume them all again. | |
1971 | Since we're not stopping threads, if we're still syscall tracing | |
1972 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1973 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1974 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1975 | ||
1976 | /* Note that gdbarch_get_syscall_number may access registers, hence | |
1977 | fill a regcache. */ | |
1978 | registers_changed (); | |
7b50312a PA |
1979 | if (linux_nat_prepare_to_resume != NULL) |
1980 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 1981 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 1982 | lp->step, GDB_SIGNAL_0); |
8817a6f2 | 1983 | lp->stopped = 0; |
ca2163eb PA |
1984 | return 1; |
1985 | } | |
1986 | ||
3d799a95 DJ |
1987 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1988 | event, we need to add the new LWP to our list (and not report the | |
1989 | trap to higher layers). This function returns non-zero if the | |
1990 | event should be ignored and we should wait again. If STOPPING is | |
1991 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1992 | |
1993 | static int | |
3d799a95 DJ |
1994 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1995 | int stopping) | |
d6b0e80f | 1996 | { |
dfd4cc63 | 1997 | int pid = ptid_get_lwp (lp->ptid); |
3d799a95 | 1998 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
3d799a95 | 1999 | int event = status >> 16; |
d6b0e80f | 2000 | |
3d799a95 DJ |
2001 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
2002 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 2003 | { |
3d799a95 DJ |
2004 | unsigned long new_pid; |
2005 | int ret; | |
2006 | ||
2007 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 2008 | |
3d799a95 DJ |
2009 | /* If we haven't already seen the new PID stop, wait for it now. */ |
2010 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
2011 | { | |
2012 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
2013 | hits the SIGSTOP, but we're already attached. */ | |
2014 | ret = my_waitpid (new_pid, &status, | |
2015 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
2016 | if (ret == -1) | |
2017 | perror_with_name (_("waiting for new child")); | |
2018 | else if (ret != new_pid) | |
2019 | internal_error (__FILE__, __LINE__, | |
2020 | _("wait returned unexpected PID %d"), ret); | |
2021 | else if (!WIFSTOPPED (status)) | |
2022 | internal_error (__FILE__, __LINE__, | |
2023 | _("wait returned unexpected status 0x%x"), status); | |
2024 | } | |
2025 | ||
3a3e9ee3 | 2026 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 | 2027 | |
26cb8b7c PA |
2028 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
2029 | { | |
2030 | /* The arch-specific native code may need to know about new | |
2031 | forks even if those end up never mapped to an | |
2032 | inferior. */ | |
2033 | if (linux_nat_new_fork != NULL) | |
2034 | linux_nat_new_fork (lp, new_pid); | |
2035 | } | |
2036 | ||
2277426b | 2037 | if (event == PTRACE_EVENT_FORK |
dfd4cc63 | 2038 | && linux_fork_checkpointing_p (ptid_get_pid (lp->ptid))) |
2277426b | 2039 | { |
2277426b PA |
2040 | /* Handle checkpointing by linux-fork.c here as a special |
2041 | case. We don't want the follow-fork-mode or 'catch fork' | |
2042 | to interfere with this. */ | |
2043 | ||
2044 | /* This won't actually modify the breakpoint list, but will | |
2045 | physically remove the breakpoints from the child. */ | |
d80ee84f | 2046 | detach_breakpoints (ptid_build (new_pid, new_pid, 0)); |
2277426b PA |
2047 | |
2048 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
2049 | if (!find_fork_pid (new_pid)) |
2050 | add_fork (new_pid); | |
2277426b PA |
2051 | |
2052 | /* Report as spurious, so that infrun doesn't want to follow | |
2053 | this fork. We're actually doing an infcall in | |
2054 | linux-fork.c. */ | |
2055 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
2056 | |
2057 | /* Report the stop to the core. */ | |
2058 | return 0; | |
2059 | } | |
2060 | ||
3d799a95 DJ |
2061 | if (event == PTRACE_EVENT_FORK) |
2062 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2063 | else if (event == PTRACE_EVENT_VFORK) | |
2064 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 2065 | else |
3d799a95 | 2066 | { |
78768c4a JK |
2067 | struct lwp_info *new_lp; |
2068 | ||
3d799a95 | 2069 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2070 | |
3c4d7e12 PA |
2071 | if (debug_linux_nat) |
2072 | fprintf_unfiltered (gdb_stdlog, | |
2073 | "LHEW: Got clone event " | |
2074 | "from LWP %d, new child is LWP %ld\n", | |
2075 | pid, new_pid); | |
2076 | ||
dfd4cc63 | 2077 | new_lp = add_lwp (ptid_build (ptid_get_pid (lp->ptid), new_pid, 0)); |
3d799a95 | 2078 | new_lp->cloned = 1; |
4c28f408 | 2079 | new_lp->stopped = 1; |
d6b0e80f | 2080 | |
3d799a95 DJ |
2081 | if (WSTOPSIG (status) != SIGSTOP) |
2082 | { | |
2083 | /* This can happen if someone starts sending signals to | |
2084 | the new thread before it gets a chance to run, which | |
2085 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2086 | This is an unlikely case, and harder to handle for | |
2087 | fork / vfork than for clone, so we do not try - but | |
2088 | we handle it for clone events here. We'll send | |
2089 | the other signal on to the thread below. */ | |
2090 | ||
2091 | new_lp->signalled = 1; | |
2092 | } | |
2093 | else | |
79395f92 PA |
2094 | { |
2095 | struct thread_info *tp; | |
2096 | ||
2097 | /* When we stop for an event in some other thread, and | |
2098 | pull the thread list just as this thread has cloned, | |
2099 | we'll have seen the new thread in the thread_db list | |
2100 | before handling the CLONE event (glibc's | |
2101 | pthread_create adds the new thread to the thread list | |
2102 | before clone'ing, and has the kernel fill in the | |
2103 | thread's tid on the clone call with | |
2104 | CLONE_PARENT_SETTID). If that happened, and the core | |
2105 | had requested the new thread to stop, we'll have | |
2106 | killed it with SIGSTOP. But since SIGSTOP is not an | |
2107 | RT signal, it can only be queued once. We need to be | |
2108 | careful to not resume the LWP if we wanted it to | |
2109 | stop. In that case, we'll leave the SIGSTOP pending. | |
a493e3e2 | 2110 | It will later be reported as GDB_SIGNAL_0. */ |
79395f92 PA |
2111 | tp = find_thread_ptid (new_lp->ptid); |
2112 | if (tp != NULL && tp->stop_requested) | |
2113 | new_lp->last_resume_kind = resume_stop; | |
2114 | else | |
2115 | status = 0; | |
2116 | } | |
d6b0e80f | 2117 | |
4c28f408 | 2118 | if (non_stop) |
3d799a95 | 2119 | { |
4c28f408 PA |
2120 | /* Add the new thread to GDB's lists as soon as possible |
2121 | so that: | |
2122 | ||
2123 | 1) the frontend doesn't have to wait for a stop to | |
2124 | display them, and, | |
2125 | ||
2126 | 2) we tag it with the correct running state. */ | |
2127 | ||
2128 | /* If the thread_db layer is active, let it know about | |
2129 | this new thread, and add it to GDB's list. */ | |
2130 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
2131 | { | |
2132 | /* We're not using thread_db. Add it to GDB's | |
2133 | list. */ | |
dfd4cc63 | 2134 | target_post_attach (ptid_get_lwp (new_lp->ptid)); |
4c28f408 PA |
2135 | add_thread (new_lp->ptid); |
2136 | } | |
2137 | ||
2138 | if (!stopping) | |
2139 | { | |
2140 | set_running (new_lp->ptid, 1); | |
2141 | set_executing (new_lp->ptid, 1); | |
e21ffe51 PA |
2142 | /* thread_db_attach_lwp -> lin_lwp_attach_lwp forced |
2143 | resume_stop. */ | |
2144 | new_lp->last_resume_kind = resume_continue; | |
4c28f408 PA |
2145 | } |
2146 | } | |
2147 | ||
79395f92 PA |
2148 | if (status != 0) |
2149 | { | |
2150 | /* We created NEW_LP so it cannot yet contain STATUS. */ | |
2151 | gdb_assert (new_lp->status == 0); | |
2152 | ||
2153 | /* Save the wait status to report later. */ | |
2154 | if (debug_linux_nat) | |
2155 | fprintf_unfiltered (gdb_stdlog, | |
2156 | "LHEW: waitpid of new LWP %ld, " | |
2157 | "saving status %s\n", | |
dfd4cc63 | 2158 | (long) ptid_get_lwp (new_lp->ptid), |
79395f92 PA |
2159 | status_to_str (status)); |
2160 | new_lp->status = status; | |
2161 | } | |
2162 | ||
ca2163eb PA |
2163 | /* Note the need to use the low target ops to resume, to |
2164 | handle resuming with PT_SYSCALL if we have syscall | |
2165 | catchpoints. */ | |
4c28f408 PA |
2166 | if (!stopping) |
2167 | { | |
3d799a95 | 2168 | new_lp->resumed = 1; |
ca2163eb | 2169 | |
79395f92 | 2170 | if (status == 0) |
ad34eb2f | 2171 | { |
e21ffe51 | 2172 | gdb_assert (new_lp->last_resume_kind == resume_continue); |
ad34eb2f JK |
2173 | if (debug_linux_nat) |
2174 | fprintf_unfiltered (gdb_stdlog, | |
79395f92 | 2175 | "LHEW: resuming new LWP %ld\n", |
dfd4cc63 | 2176 | ptid_get_lwp (new_lp->ptid)); |
7b50312a PA |
2177 | if (linux_nat_prepare_to_resume != NULL) |
2178 | linux_nat_prepare_to_resume (new_lp); | |
79395f92 | 2179 | linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid), |
a493e3e2 | 2180 | 0, GDB_SIGNAL_0); |
79395f92 | 2181 | new_lp->stopped = 0; |
ad34eb2f JK |
2182 | } |
2183 | } | |
d6b0e80f | 2184 | |
3d799a95 DJ |
2185 | if (debug_linux_nat) |
2186 | fprintf_unfiltered (gdb_stdlog, | |
3c4d7e12 | 2187 | "LHEW: resuming parent LWP %d\n", pid); |
7b50312a PA |
2188 | if (linux_nat_prepare_to_resume != NULL) |
2189 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
2190 | linux_ops->to_resume (linux_ops, |
2191 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
a493e3e2 | 2192 | 0, GDB_SIGNAL_0); |
8817a6f2 | 2193 | lp->stopped = 0; |
3d799a95 DJ |
2194 | return 1; |
2195 | } | |
2196 | ||
2197 | return 0; | |
d6b0e80f AC |
2198 | } |
2199 | ||
3d799a95 DJ |
2200 | if (event == PTRACE_EVENT_EXEC) |
2201 | { | |
a75724bc PA |
2202 | if (debug_linux_nat) |
2203 | fprintf_unfiltered (gdb_stdlog, | |
2204 | "LHEW: Got exec event from LWP %ld\n", | |
dfd4cc63 | 2205 | ptid_get_lwp (lp->ptid)); |
a75724bc | 2206 | |
3d799a95 DJ |
2207 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2208 | ourstatus->value.execd_pathname | |
8dd27370 | 2209 | = xstrdup (linux_child_pid_to_exec_file (NULL, pid)); |
3d799a95 | 2210 | |
6c95b8df PA |
2211 | return 0; |
2212 | } | |
2213 | ||
2214 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2215 | { | |
2216 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2217 | { |
6c95b8df | 2218 | if (debug_linux_nat) |
3e43a32a MS |
2219 | fprintf_unfiltered (gdb_stdlog, |
2220 | "LHEW: Got expected PTRACE_EVENT_" | |
2221 | "VFORK_DONE from LWP %ld: stopping\n", | |
dfd4cc63 | 2222 | ptid_get_lwp (lp->ptid)); |
3d799a95 | 2223 | |
6c95b8df PA |
2224 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2225 | return 0; | |
3d799a95 DJ |
2226 | } |
2227 | ||
6c95b8df | 2228 | if (debug_linux_nat) |
3e43a32a MS |
2229 | fprintf_unfiltered (gdb_stdlog, |
2230 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
2231 | "from LWP %ld: resuming\n", | |
dfd4cc63 LM |
2232 | ptid_get_lwp (lp->ptid)); |
2233 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); | |
6c95b8df | 2234 | return 1; |
3d799a95 DJ |
2235 | } |
2236 | ||
2237 | internal_error (__FILE__, __LINE__, | |
2238 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2239 | } |
2240 | ||
2241 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
2242 | exited. */ | |
2243 | ||
2244 | static int | |
2245 | wait_lwp (struct lwp_info *lp) | |
2246 | { | |
2247 | pid_t pid; | |
432b4d03 | 2248 | int status = 0; |
d6b0e80f | 2249 | int thread_dead = 0; |
432b4d03 | 2250 | sigset_t prev_mask; |
d6b0e80f AC |
2251 | |
2252 | gdb_assert (!lp->stopped); | |
2253 | gdb_assert (lp->status == 0); | |
2254 | ||
432b4d03 JK |
2255 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2256 | block_child_signals (&prev_mask); | |
2257 | ||
2258 | for (;;) | |
d6b0e80f | 2259 | { |
432b4d03 JK |
2260 | /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind |
2261 | was right and we should just call sigsuspend. */ | |
2262 | ||
dfd4cc63 | 2263 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, WNOHANG); |
d6b0e80f | 2264 | if (pid == -1 && errno == ECHILD) |
dfd4cc63 | 2265 | pid = my_waitpid (ptid_get_lwp (lp->ptid), &status, __WCLONE | WNOHANG); |
a9f4bb21 PA |
2266 | if (pid == -1 && errno == ECHILD) |
2267 | { | |
2268 | /* The thread has previously exited. We need to delete it | |
2269 | now because, for some vendor 2.4 kernels with NPTL | |
2270 | support backported, there won't be an exit event unless | |
2271 | it is the main thread. 2.6 kernels will report an exit | |
2272 | event for each thread that exits, as expected. */ | |
2273 | thread_dead = 1; | |
2274 | if (debug_linux_nat) | |
2275 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
2276 | target_pid_to_str (lp->ptid)); | |
2277 | } | |
432b4d03 JK |
2278 | if (pid != 0) |
2279 | break; | |
2280 | ||
2281 | /* Bugs 10970, 12702. | |
2282 | Thread group leader may have exited in which case we'll lock up in | |
2283 | waitpid if there are other threads, even if they are all zombies too. | |
2284 | Basically, we're not supposed to use waitpid this way. | |
2285 | __WCLONE is not applicable for the leader so we can't use that. | |
2286 | LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED | |
2287 | process; it gets ESRCH both for the zombie and for running processes. | |
2288 | ||
2289 | As a workaround, check if we're waiting for the thread group leader and | |
2290 | if it's a zombie, and avoid calling waitpid if it is. | |
2291 | ||
2292 | This is racy, what if the tgl becomes a zombie right after we check? | |
2293 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2294 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2295 | |
dfd4cc63 LM |
2296 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid) |
2297 | && linux_proc_pid_is_zombie (ptid_get_lwp (lp->ptid))) | |
d6b0e80f | 2298 | { |
d6b0e80f AC |
2299 | thread_dead = 1; |
2300 | if (debug_linux_nat) | |
432b4d03 JK |
2301 | fprintf_unfiltered (gdb_stdlog, |
2302 | "WL: Thread group leader %s vanished.\n", | |
d6b0e80f | 2303 | target_pid_to_str (lp->ptid)); |
432b4d03 | 2304 | break; |
d6b0e80f | 2305 | } |
432b4d03 JK |
2306 | |
2307 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2308 | get invoked despite our caller had them intentionally blocked by | |
2309 | block_child_signals. This is sensitive only to the loop of | |
2310 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2311 | again before it gets to sigsuspend so we can safely let the handlers | |
2312 | get executed here. */ | |
2313 | ||
2314 | sigsuspend (&suspend_mask); | |
2315 | } | |
2316 | ||
2317 | restore_child_signals_mask (&prev_mask); | |
2318 | ||
d6b0e80f AC |
2319 | if (!thread_dead) |
2320 | { | |
dfd4cc63 | 2321 | gdb_assert (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
2322 | |
2323 | if (debug_linux_nat) | |
2324 | { | |
2325 | fprintf_unfiltered (gdb_stdlog, | |
2326 | "WL: waitpid %s received %s\n", | |
2327 | target_pid_to_str (lp->ptid), | |
2328 | status_to_str (status)); | |
2329 | } | |
d6b0e80f | 2330 | |
a9f4bb21 PA |
2331 | /* Check if the thread has exited. */ |
2332 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2333 | { | |
2334 | thread_dead = 1; | |
2335 | if (debug_linux_nat) | |
2336 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
2337 | target_pid_to_str (lp->ptid)); | |
2338 | } | |
d6b0e80f AC |
2339 | } |
2340 | ||
2341 | if (thread_dead) | |
2342 | { | |
e26af52f | 2343 | exit_lwp (lp); |
d6b0e80f AC |
2344 | return 0; |
2345 | } | |
2346 | ||
2347 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2348 | lp->stopped = 1; |
d6b0e80f | 2349 | |
ca2163eb PA |
2350 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2351 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2352 | { | |
2353 | /* No longer need the sysgood bit. The ptrace event ends up | |
2354 | recorded in lp->waitstatus if we care for it. We can carry | |
2355 | on handling the event like a regular SIGTRAP from here | |
2356 | on. */ | |
2357 | status = W_STOPCODE (SIGTRAP); | |
2358 | if (linux_handle_syscall_trap (lp, 1)) | |
2359 | return wait_lwp (lp); | |
2360 | } | |
2361 | ||
d6b0e80f AC |
2362 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2363 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2364 | { | |
2365 | if (debug_linux_nat) | |
2366 | fprintf_unfiltered (gdb_stdlog, | |
2367 | "WL: Handling extended status 0x%06x\n", | |
2368 | status); | |
3d799a95 | 2369 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
2370 | return wait_lwp (lp); |
2371 | } | |
2372 | ||
2373 | return status; | |
2374 | } | |
2375 | ||
2376 | /* Send a SIGSTOP to LP. */ | |
2377 | ||
2378 | static int | |
2379 | stop_callback (struct lwp_info *lp, void *data) | |
2380 | { | |
2381 | if (!lp->stopped && !lp->signalled) | |
2382 | { | |
2383 | int ret; | |
2384 | ||
2385 | if (debug_linux_nat) | |
2386 | { | |
2387 | fprintf_unfiltered (gdb_stdlog, | |
2388 | "SC: kill %s **<SIGSTOP>**\n", | |
2389 | target_pid_to_str (lp->ptid)); | |
2390 | } | |
2391 | errno = 0; | |
dfd4cc63 | 2392 | ret = kill_lwp (ptid_get_lwp (lp->ptid), SIGSTOP); |
d6b0e80f AC |
2393 | if (debug_linux_nat) |
2394 | { | |
2395 | fprintf_unfiltered (gdb_stdlog, | |
2396 | "SC: lwp kill %d %s\n", | |
2397 | ret, | |
2398 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2399 | } | |
2400 | ||
2401 | lp->signalled = 1; | |
2402 | gdb_assert (lp->status == 0); | |
2403 | } | |
2404 | ||
2405 | return 0; | |
2406 | } | |
2407 | ||
7b50312a PA |
2408 | /* Request a stop on LWP. */ |
2409 | ||
2410 | void | |
2411 | linux_stop_lwp (struct lwp_info *lwp) | |
2412 | { | |
2413 | stop_callback (lwp, NULL); | |
2414 | } | |
2415 | ||
57380f4e | 2416 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2417 | |
2418 | static int | |
57380f4e DJ |
2419 | linux_nat_has_pending_sigint (int pid) |
2420 | { | |
2421 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2422 | |
2423 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2424 | ||
2425 | if (sigismember (&pending, SIGINT) | |
2426 | && !sigismember (&ignored, SIGINT)) | |
2427 | return 1; | |
2428 | ||
2429 | return 0; | |
2430 | } | |
2431 | ||
2432 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2433 | ||
2434 | static int | |
2435 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2436 | { |
57380f4e DJ |
2437 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2438 | flag to consume the next one. */ | |
2439 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2440 | && WSTOPSIG (lp->status) == SIGINT) | |
2441 | lp->status = 0; | |
2442 | else | |
2443 | lp->ignore_sigint = 1; | |
2444 | ||
2445 | return 0; | |
2446 | } | |
2447 | ||
2448 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2449 | This function is called after we know the LWP has stopped; if the LWP | |
2450 | stopped before the expected SIGINT was delivered, then it will never have | |
2451 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2452 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2453 | |
57380f4e DJ |
2454 | static void |
2455 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2456 | { | |
2457 | if (!lp->ignore_sigint) | |
2458 | return; | |
2459 | ||
dfd4cc63 | 2460 | if (!linux_nat_has_pending_sigint (ptid_get_lwp (lp->ptid))) |
57380f4e DJ |
2461 | { |
2462 | if (debug_linux_nat) | |
2463 | fprintf_unfiltered (gdb_stdlog, | |
2464 | "MCIS: Clearing bogus flag for %s\n", | |
2465 | target_pid_to_str (lp->ptid)); | |
2466 | lp->ignore_sigint = 0; | |
2467 | } | |
2468 | } | |
2469 | ||
ebec9a0f PA |
2470 | /* Fetch the possible triggered data watchpoint info and store it in |
2471 | LP. | |
2472 | ||
2473 | On some archs, like x86, that use debug registers to set | |
2474 | watchpoints, it's possible that the way to know which watched | |
2475 | address trapped, is to check the register that is used to select | |
2476 | which address to watch. Problem is, between setting the watchpoint | |
2477 | and reading back which data address trapped, the user may change | |
2478 | the set of watchpoints, and, as a consequence, GDB changes the | |
2479 | debug registers in the inferior. To avoid reading back a stale | |
2480 | stopped-data-address when that happens, we cache in LP the fact | |
2481 | that a watchpoint trapped, and the corresponding data address, as | |
2482 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2483 | registers meanwhile, we have the cached data we can rely on. */ | |
2484 | ||
2485 | static void | |
2486 | save_sigtrap (struct lwp_info *lp) | |
2487 | { | |
2488 | struct cleanup *old_chain; | |
2489 | ||
2490 | if (linux_ops->to_stopped_by_watchpoint == NULL) | |
2491 | { | |
2492 | lp->stopped_by_watchpoint = 0; | |
2493 | return; | |
2494 | } | |
2495 | ||
2496 | old_chain = save_inferior_ptid (); | |
2497 | inferior_ptid = lp->ptid; | |
2498 | ||
6a109b6b | 2499 | lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint (linux_ops); |
ebec9a0f PA |
2500 | |
2501 | if (lp->stopped_by_watchpoint) | |
2502 | { | |
2503 | if (linux_ops->to_stopped_data_address != NULL) | |
2504 | lp->stopped_data_address_p = | |
2505 | linux_ops->to_stopped_data_address (¤t_target, | |
2506 | &lp->stopped_data_address); | |
2507 | else | |
2508 | lp->stopped_data_address_p = 0; | |
2509 | } | |
2510 | ||
2511 | do_cleanups (old_chain); | |
2512 | } | |
2513 | ||
2514 | /* See save_sigtrap. */ | |
2515 | ||
2516 | static int | |
6a109b6b | 2517 | linux_nat_stopped_by_watchpoint (struct target_ops *ops) |
ebec9a0f PA |
2518 | { |
2519 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2520 | ||
2521 | gdb_assert (lp != NULL); | |
2522 | ||
2523 | return lp->stopped_by_watchpoint; | |
2524 | } | |
2525 | ||
2526 | static int | |
2527 | linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) | |
2528 | { | |
2529 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2530 | ||
2531 | gdb_assert (lp != NULL); | |
2532 | ||
2533 | *addr_p = lp->stopped_data_address; | |
2534 | ||
2535 | return lp->stopped_data_address_p; | |
2536 | } | |
2537 | ||
26ab7092 JK |
2538 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2539 | ||
2540 | static int | |
2541 | sigtrap_is_event (int status) | |
2542 | { | |
2543 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2544 | } | |
2545 | ||
2546 | /* SIGTRAP-like events recognizer. */ | |
2547 | ||
2548 | static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event; | |
2549 | ||
00390b84 JK |
2550 | /* Check for SIGTRAP-like events in LP. */ |
2551 | ||
2552 | static int | |
2553 | linux_nat_lp_status_is_event (struct lwp_info *lp) | |
2554 | { | |
2555 | /* We check for lp->waitstatus in addition to lp->status, because we can | |
2556 | have pending process exits recorded in lp->status | |
2557 | and W_EXITCODE(0,0) == 0. We should probably have an additional | |
2558 | lp->status_p flag. */ | |
2559 | ||
2560 | return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE | |
2561 | && linux_nat_status_is_event (lp->status)); | |
2562 | } | |
2563 | ||
26ab7092 JK |
2564 | /* Set alternative SIGTRAP-like events recognizer. If |
2565 | breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be | |
2566 | applied. */ | |
2567 | ||
2568 | void | |
2569 | linux_nat_set_status_is_event (struct target_ops *t, | |
2570 | int (*status_is_event) (int status)) | |
2571 | { | |
2572 | linux_nat_status_is_event = status_is_event; | |
2573 | } | |
2574 | ||
57380f4e DJ |
2575 | /* Wait until LP is stopped. */ |
2576 | ||
2577 | static int | |
2578 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2579 | { | |
dfd4cc63 | 2580 | struct inferior *inf = find_inferior_pid (ptid_get_pid (lp->ptid)); |
6c95b8df PA |
2581 | |
2582 | /* If this is a vfork parent, bail out, it is not going to report | |
2583 | any SIGSTOP until the vfork is done with. */ | |
2584 | if (inf->vfork_child != NULL) | |
2585 | return 0; | |
2586 | ||
d6b0e80f AC |
2587 | if (!lp->stopped) |
2588 | { | |
2589 | int status; | |
2590 | ||
2591 | status = wait_lwp (lp); | |
2592 | if (status == 0) | |
2593 | return 0; | |
2594 | ||
57380f4e DJ |
2595 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2596 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2597 | { |
57380f4e | 2598 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2599 | |
2600 | errno = 0; | |
dfd4cc63 | 2601 | ptrace (PTRACE_CONT, ptid_get_lwp (lp->ptid), 0, 0); |
8817a6f2 | 2602 | lp->stopped = 0; |
d6b0e80f AC |
2603 | if (debug_linux_nat) |
2604 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2605 | "PTRACE_CONT %s, 0, 0 (%s) " |
2606 | "(discarding SIGINT)\n", | |
d6b0e80f AC |
2607 | target_pid_to_str (lp->ptid), |
2608 | errno ? safe_strerror (errno) : "OK"); | |
2609 | ||
57380f4e | 2610 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2611 | } |
2612 | ||
57380f4e DJ |
2613 | maybe_clear_ignore_sigint (lp); |
2614 | ||
d6b0e80f AC |
2615 | if (WSTOPSIG (status) != SIGSTOP) |
2616 | { | |
e5ef252a | 2617 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2618 | |
e5ef252a PA |
2619 | save_sigtrap (lp); |
2620 | ||
2621 | if (debug_linux_nat) | |
2622 | fprintf_unfiltered (gdb_stdlog, | |
2623 | "SWC: Pending event %s in %s\n", | |
2624 | status_to_str ((int) status), | |
2625 | target_pid_to_str (lp->ptid)); | |
2626 | ||
2627 | /* Save the sigtrap event. */ | |
2628 | lp->status = status; | |
e5ef252a | 2629 | gdb_assert (lp->signalled); |
d6b0e80f AC |
2630 | } |
2631 | else | |
2632 | { | |
2633 | /* We caught the SIGSTOP that we intended to catch, so | |
2634 | there's no SIGSTOP pending. */ | |
e5ef252a PA |
2635 | |
2636 | if (debug_linux_nat) | |
2637 | fprintf_unfiltered (gdb_stdlog, | |
2638 | "SWC: Delayed SIGSTOP caught for %s.\n", | |
2639 | target_pid_to_str (lp->ptid)); | |
2640 | ||
e5ef252a PA |
2641 | /* Reset SIGNALLED only after the stop_wait_callback call |
2642 | above as it does gdb_assert on SIGNALLED. */ | |
d6b0e80f AC |
2643 | lp->signalled = 0; |
2644 | } | |
2645 | } | |
2646 | ||
2647 | return 0; | |
2648 | } | |
2649 | ||
d6b0e80f AC |
2650 | /* Return non-zero if LP has a wait status pending. */ |
2651 | ||
2652 | static int | |
2653 | status_callback (struct lwp_info *lp, void *data) | |
2654 | { | |
2655 | /* Only report a pending wait status if we pretend that this has | |
2656 | indeed been resumed. */ | |
ca2163eb PA |
2657 | if (!lp->resumed) |
2658 | return 0; | |
2659 | ||
2660 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2661 | { | |
2662 | /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event, | |
766062f6 | 2663 | or a pending process exit. Note that `W_EXITCODE(0,0) == |
ca2163eb PA |
2664 | 0', so a clean process exit can not be stored pending in |
2665 | lp->status, it is indistinguishable from | |
2666 | no-pending-status. */ | |
2667 | return 1; | |
2668 | } | |
2669 | ||
2670 | if (lp->status != 0) | |
2671 | return 1; | |
2672 | ||
2673 | return 0; | |
d6b0e80f AC |
2674 | } |
2675 | ||
2676 | /* Return non-zero if LP isn't stopped. */ | |
2677 | ||
2678 | static int | |
2679 | running_callback (struct lwp_info *lp, void *data) | |
2680 | { | |
25289eb2 PA |
2681 | return (!lp->stopped |
2682 | || ((lp->status != 0 | |
2683 | || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2684 | && lp->resumed)); | |
d6b0e80f AC |
2685 | } |
2686 | ||
2687 | /* Count the LWP's that have had events. */ | |
2688 | ||
2689 | static int | |
2690 | count_events_callback (struct lwp_info *lp, void *data) | |
2691 | { | |
2692 | int *count = data; | |
2693 | ||
2694 | gdb_assert (count != NULL); | |
2695 | ||
e09490f1 | 2696 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2697 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2698 | (*count)++; |
2699 | ||
2700 | return 0; | |
2701 | } | |
2702 | ||
2703 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2704 | ||
2705 | static int | |
2706 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2707 | { | |
25289eb2 PA |
2708 | if (lp->last_resume_kind == resume_step |
2709 | && lp->status != 0) | |
d6b0e80f AC |
2710 | return 1; |
2711 | else | |
2712 | return 0; | |
2713 | } | |
2714 | ||
2715 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2716 | ||
2717 | static int | |
2718 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2719 | { | |
2720 | int *selector = data; | |
2721 | ||
2722 | gdb_assert (selector != NULL); | |
2723 | ||
1777feb0 | 2724 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
00390b84 | 2725 | if (lp->resumed && linux_nat_lp_status_is_event (lp)) |
d6b0e80f AC |
2726 | if ((*selector)-- == 0) |
2727 | return 1; | |
2728 | ||
2729 | return 0; | |
2730 | } | |
2731 | ||
710151dd PA |
2732 | static int |
2733 | cancel_breakpoint (struct lwp_info *lp) | |
2734 | { | |
2735 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2736 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2737 | LWP. We will handle the current event, eventually we will resume | |
2738 | this LWP, and this breakpoint will trap again. | |
2739 | ||
2740 | If we do not do this, then we run the risk that the user will | |
2741 | delete or disable the breakpoint, but the LWP will have already | |
2742 | tripped on it. */ | |
2743 | ||
515630c5 UW |
2744 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2745 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2746 | CORE_ADDR pc; | |
2747 | ||
118e6252 | 2748 | pc = regcache_read_pc (regcache) - target_decr_pc_after_break (gdbarch); |
6c95b8df | 2749 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
710151dd PA |
2750 | { |
2751 | if (debug_linux_nat) | |
2752 | fprintf_unfiltered (gdb_stdlog, | |
2753 | "CB: Push back breakpoint for %s\n", | |
2754 | target_pid_to_str (lp->ptid)); | |
2755 | ||
2756 | /* Back up the PC if necessary. */ | |
118e6252 | 2757 | if (target_decr_pc_after_break (gdbarch)) |
515630c5 UW |
2758 | regcache_write_pc (regcache, pc); |
2759 | ||
710151dd PA |
2760 | return 1; |
2761 | } | |
2762 | return 0; | |
2763 | } | |
2764 | ||
d6b0e80f AC |
2765 | static int |
2766 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2767 | { | |
2768 | struct lwp_info *event_lp = data; | |
2769 | ||
2770 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2771 | if (lp == event_lp) | |
2772 | return 0; | |
2773 | ||
2774 | /* If a LWP other than the LWP that we're reporting an event for has | |
2775 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2776 | then just arrange for it to hit it again later. We don't keep | |
2777 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2778 | LWP. We will handle the current event, eventually we will resume | |
2779 | all LWPs, and this one will get its breakpoint trap again. | |
2780 | ||
2781 | If we do not do this, then we run the risk that the user will | |
2782 | delete or disable the breakpoint, but the LWP will have already | |
2783 | tripped on it. */ | |
2784 | ||
00390b84 | 2785 | if (linux_nat_lp_status_is_event (lp) |
710151dd PA |
2786 | && cancel_breakpoint (lp)) |
2787 | /* Throw away the SIGTRAP. */ | |
2788 | lp->status = 0; | |
d6b0e80f AC |
2789 | |
2790 | return 0; | |
2791 | } | |
2792 | ||
2793 | /* Select one LWP out of those that have events pending. */ | |
2794 | ||
2795 | static void | |
d90e17a7 | 2796 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2797 | { |
2798 | int num_events = 0; | |
2799 | int random_selector; | |
2800 | struct lwp_info *event_lp; | |
2801 | ||
ac264b3b | 2802 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2803 | (*orig_lp)->status = *status; |
2804 | ||
2805 | /* Give preference to any LWP that is being single-stepped. */ | |
d90e17a7 PA |
2806 | event_lp = iterate_over_lwps (filter, |
2807 | select_singlestep_lwp_callback, NULL); | |
d6b0e80f AC |
2808 | if (event_lp != NULL) |
2809 | { | |
2810 | if (debug_linux_nat) | |
2811 | fprintf_unfiltered (gdb_stdlog, | |
2812 | "SEL: Select single-step %s\n", | |
2813 | target_pid_to_str (event_lp->ptid)); | |
2814 | } | |
2815 | else | |
2816 | { | |
2817 | /* No single-stepping LWP. Select one at random, out of those | |
2818 | which have had SIGTRAP events. */ | |
2819 | ||
2820 | /* First see how many SIGTRAP events we have. */ | |
d90e17a7 | 2821 | iterate_over_lwps (filter, count_events_callback, &num_events); |
d6b0e80f AC |
2822 | |
2823 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2824 | random_selector = (int) | |
2825 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2826 | ||
2827 | if (debug_linux_nat && num_events > 1) | |
2828 | fprintf_unfiltered (gdb_stdlog, | |
2829 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2830 | num_events, random_selector); | |
2831 | ||
d90e17a7 PA |
2832 | event_lp = iterate_over_lwps (filter, |
2833 | select_event_lwp_callback, | |
d6b0e80f AC |
2834 | &random_selector); |
2835 | } | |
2836 | ||
2837 | if (event_lp != NULL) | |
2838 | { | |
2839 | /* Switch the event LWP. */ | |
2840 | *orig_lp = event_lp; | |
2841 | *status = event_lp->status; | |
2842 | } | |
2843 | ||
2844 | /* Flush the wait status for the event LWP. */ | |
2845 | (*orig_lp)->status = 0; | |
2846 | } | |
2847 | ||
2848 | /* Return non-zero if LP has been resumed. */ | |
2849 | ||
2850 | static int | |
2851 | resumed_callback (struct lwp_info *lp, void *data) | |
2852 | { | |
2853 | return lp->resumed; | |
2854 | } | |
2855 | ||
12d9289a PA |
2856 | /* Stop an active thread, verify it still exists, then resume it. If |
2857 | the thread ends up with a pending status, then it is not resumed, | |
2858 | and *DATA (really a pointer to int), is set. */ | |
d6b0e80f AC |
2859 | |
2860 | static int | |
2861 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2862 | { | |
12d9289a PA |
2863 | int *new_pending_p = data; |
2864 | ||
25289eb2 | 2865 | if (!lp->stopped) |
d6b0e80f | 2866 | { |
25289eb2 PA |
2867 | ptid_t ptid = lp->ptid; |
2868 | ||
d6b0e80f AC |
2869 | stop_callback (lp, NULL); |
2870 | stop_wait_callback (lp, NULL); | |
25289eb2 PA |
2871 | |
2872 | /* Resume if the lwp still exists, and the core wanted it | |
2873 | running. */ | |
12d9289a PA |
2874 | lp = find_lwp_pid (ptid); |
2875 | if (lp != NULL) | |
25289eb2 | 2876 | { |
12d9289a PA |
2877 | if (lp->last_resume_kind == resume_stop |
2878 | && lp->status == 0) | |
2879 | { | |
2880 | /* The core wanted the LWP to stop. Even if it stopped | |
2881 | cleanly (with SIGSTOP), leave the event pending. */ | |
2882 | if (debug_linux_nat) | |
2883 | fprintf_unfiltered (gdb_stdlog, | |
2884 | "SARC: core wanted LWP %ld stopped " | |
2885 | "(leaving SIGSTOP pending)\n", | |
dfd4cc63 | 2886 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2887 | lp->status = W_STOPCODE (SIGSTOP); |
2888 | } | |
2889 | ||
2890 | if (lp->status == 0) | |
2891 | { | |
2892 | if (debug_linux_nat) | |
2893 | fprintf_unfiltered (gdb_stdlog, | |
2894 | "SARC: re-resuming LWP %ld\n", | |
dfd4cc63 | 2895 | ptid_get_lwp (lp->ptid)); |
e5ef252a | 2896 | resume_lwp (lp, lp->step, GDB_SIGNAL_0); |
12d9289a PA |
2897 | } |
2898 | else | |
2899 | { | |
2900 | if (debug_linux_nat) | |
2901 | fprintf_unfiltered (gdb_stdlog, | |
2902 | "SARC: not re-resuming LWP %ld " | |
2903 | "(has pending)\n", | |
dfd4cc63 | 2904 | ptid_get_lwp (lp->ptid)); |
12d9289a PA |
2905 | if (new_pending_p) |
2906 | *new_pending_p = 1; | |
2907 | } | |
25289eb2 | 2908 | } |
d6b0e80f AC |
2909 | } |
2910 | return 0; | |
2911 | } | |
2912 | ||
02f3fc28 | 2913 | /* Check if we should go on and pass this event to common code. |
12d9289a PA |
2914 | Return the affected lwp if we are, or NULL otherwise. If we stop |
2915 | all lwps temporarily, we may end up with new pending events in some | |
2916 | other lwp. In that case set *NEW_PENDING_P to true. */ | |
2917 | ||
02f3fc28 | 2918 | static struct lwp_info * |
0e5bf2a8 | 2919 | linux_nat_filter_event (int lwpid, int status, int *new_pending_p) |
02f3fc28 PA |
2920 | { |
2921 | struct lwp_info *lp; | |
2922 | ||
12d9289a PA |
2923 | *new_pending_p = 0; |
2924 | ||
02f3fc28 PA |
2925 | lp = find_lwp_pid (pid_to_ptid (lwpid)); |
2926 | ||
2927 | /* Check for stop events reported by a process we didn't already | |
2928 | know about - anything not already in our LWP list. | |
2929 | ||
2930 | If we're expecting to receive stopped processes after | |
2931 | fork, vfork, and clone events, then we'll just add the | |
2932 | new one to our list and go back to waiting for the event | |
2933 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2934 | from waitpid before or after the event is. |
2935 | ||
2936 | But note the case of a non-leader thread exec'ing after the | |
2937 | leader having exited, and gone from our lists. The non-leader | |
2938 | thread changes its tid to the tgid. */ | |
2939 | ||
2940 | if (WIFSTOPPED (status) && lp == NULL | |
2941 | && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC)) | |
2942 | { | |
2943 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2944 | if (debug_linux_nat) | |
2945 | fprintf_unfiltered (gdb_stdlog, | |
2946 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2947 | lwpid); | |
2948 | ||
dfd4cc63 | 2949 | lp = add_lwp (ptid_build (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2950 | lp->stopped = 1; |
2951 | lp->resumed = 1; | |
2952 | add_thread (lp->ptid); | |
2953 | } | |
2954 | ||
02f3fc28 PA |
2955 | if (WIFSTOPPED (status) && !lp) |
2956 | { | |
84636d28 | 2957 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2958 | return NULL; |
2959 | } | |
2960 | ||
2961 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2962 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2963 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2964 | exits. */ |
2965 | if (!WIFSTOPPED (status) && !lp) | |
2966 | return NULL; | |
2967 | ||
8817a6f2 PA |
2968 | /* This LWP is stopped now. (And if dead, this prevents it from |
2969 | ever being continued.) */ | |
2970 | lp->stopped = 1; | |
2971 | ||
ca2163eb PA |
2972 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2973 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2974 | { | |
2975 | /* No longer need the sysgood bit. The ptrace event ends up | |
2976 | recorded in lp->waitstatus if we care for it. We can carry | |
2977 | on handling the event like a regular SIGTRAP from here | |
2978 | on. */ | |
2979 | status = W_STOPCODE (SIGTRAP); | |
2980 | if (linux_handle_syscall_trap (lp, 0)) | |
2981 | return NULL; | |
2982 | } | |
02f3fc28 | 2983 | |
ca2163eb PA |
2984 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
2985 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
02f3fc28 PA |
2986 | { |
2987 | if (debug_linux_nat) | |
2988 | fprintf_unfiltered (gdb_stdlog, | |
2989 | "LLW: Handling extended status 0x%06x\n", | |
2990 | status); | |
2991 | if (linux_handle_extended_wait (lp, status, 0)) | |
2992 | return NULL; | |
2993 | } | |
2994 | ||
26ab7092 | 2995 | if (linux_nat_status_is_event (status)) |
da559b09 | 2996 | save_sigtrap (lp); |
ca2163eb | 2997 | |
02f3fc28 | 2998 | /* Check if the thread has exited. */ |
d90e17a7 | 2999 | if ((WIFEXITED (status) || WIFSIGNALED (status)) |
dfd4cc63 | 3000 | && num_lwps (ptid_get_pid (lp->ptid)) > 1) |
02f3fc28 | 3001 | { |
9db03742 JB |
3002 | /* If this is the main thread, we must stop all threads and verify |
3003 | if they are still alive. This is because in the nptl thread model | |
3004 | on Linux 2.4, there is no signal issued for exiting LWPs | |
02f3fc28 PA |
3005 | other than the main thread. We only get the main thread exit |
3006 | signal once all child threads have already exited. If we | |
3007 | stop all the threads and use the stop_wait_callback to check | |
3008 | if they have exited we can determine whether this signal | |
3009 | should be ignored or whether it means the end of the debugged | |
3010 | application, regardless of which threading model is being | |
5d3b6af6 | 3011 | used. */ |
dfd4cc63 | 3012 | if (ptid_get_pid (lp->ptid) == ptid_get_lwp (lp->ptid)) |
02f3fc28 | 3013 | { |
dfd4cc63 | 3014 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (lp->ptid)), |
12d9289a | 3015 | stop_and_resume_callback, new_pending_p); |
02f3fc28 PA |
3016 | } |
3017 | ||
3018 | if (debug_linux_nat) | |
3019 | fprintf_unfiltered (gdb_stdlog, | |
3020 | "LLW: %s exited.\n", | |
3021 | target_pid_to_str (lp->ptid)); | |
3022 | ||
dfd4cc63 | 3023 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1) |
9db03742 JB |
3024 | { |
3025 | /* If there is at least one more LWP, then the exit signal | |
3026 | was not the end of the debugged application and should be | |
3027 | ignored. */ | |
3028 | exit_lwp (lp); | |
3029 | return NULL; | |
3030 | } | |
02f3fc28 PA |
3031 | } |
3032 | ||
3033 | /* Check if the current LWP has previously exited. In the nptl | |
3034 | thread model, LWPs other than the main thread do not issue | |
3035 | signals when they exit so we must check whenever the thread has | |
3036 | stopped. A similar check is made in stop_wait_callback(). */ | |
dfd4cc63 | 3037 | if (num_lwps (ptid_get_pid (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid)) |
02f3fc28 | 3038 | { |
dfd4cc63 | 3039 | ptid_t ptid = pid_to_ptid (ptid_get_pid (lp->ptid)); |
d90e17a7 | 3040 | |
02f3fc28 PA |
3041 | if (debug_linux_nat) |
3042 | fprintf_unfiltered (gdb_stdlog, | |
3043 | "LLW: %s exited.\n", | |
3044 | target_pid_to_str (lp->ptid)); | |
3045 | ||
3046 | exit_lwp (lp); | |
3047 | ||
3048 | /* Make sure there is at least one thread running. */ | |
d90e17a7 | 3049 | gdb_assert (iterate_over_lwps (ptid, running_callback, NULL)); |
02f3fc28 PA |
3050 | |
3051 | /* Discard the event. */ | |
3052 | return NULL; | |
3053 | } | |
3054 | ||
3055 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
3056 | an attempt to stop an LWP. */ | |
3057 | if (lp->signalled | |
3058 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3059 | { | |
3060 | if (debug_linux_nat) | |
3061 | fprintf_unfiltered (gdb_stdlog, | |
3062 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
3063 | target_pid_to_str (lp->ptid)); | |
3064 | ||
02f3fc28 PA |
3065 | lp->signalled = 0; |
3066 | ||
25289eb2 PA |
3067 | if (lp->last_resume_kind != resume_stop) |
3068 | { | |
3069 | /* This is a delayed SIGSTOP. */ | |
02f3fc28 | 3070 | |
25289eb2 PA |
3071 | registers_changed (); |
3072 | ||
7b50312a PA |
3073 | if (linux_nat_prepare_to_resume != NULL) |
3074 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3075 | linux_ops->to_resume (linux_ops, |
3076 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
3077 | lp->step, GDB_SIGNAL_0); | |
25289eb2 PA |
3078 | if (debug_linux_nat) |
3079 | fprintf_unfiltered (gdb_stdlog, | |
3080 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
3081 | lp->step ? | |
3082 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3083 | target_pid_to_str (lp->ptid)); | |
02f3fc28 | 3084 | |
25289eb2 PA |
3085 | lp->stopped = 0; |
3086 | gdb_assert (lp->resumed); | |
02f3fc28 | 3087 | |
25289eb2 PA |
3088 | /* Discard the event. */ |
3089 | return NULL; | |
3090 | } | |
02f3fc28 PA |
3091 | } |
3092 | ||
57380f4e DJ |
3093 | /* Make sure we don't report a SIGINT that we have already displayed |
3094 | for another thread. */ | |
3095 | if (lp->ignore_sigint | |
3096 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3097 | { | |
3098 | if (debug_linux_nat) | |
3099 | fprintf_unfiltered (gdb_stdlog, | |
3100 | "LLW: Delayed SIGINT caught for %s.\n", | |
3101 | target_pid_to_str (lp->ptid)); | |
3102 | ||
3103 | /* This is a delayed SIGINT. */ | |
3104 | lp->ignore_sigint = 0; | |
3105 | ||
3106 | registers_changed (); | |
7b50312a PA |
3107 | if (linux_nat_prepare_to_resume != NULL) |
3108 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3109 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3110 | lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3111 | if (debug_linux_nat) |
3112 | fprintf_unfiltered (gdb_stdlog, | |
3113 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3114 | lp->step ? | |
3115 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3116 | target_pid_to_str (lp->ptid)); | |
3117 | ||
3118 | lp->stopped = 0; | |
3119 | gdb_assert (lp->resumed); | |
3120 | ||
3121 | /* Discard the event. */ | |
3122 | return NULL; | |
3123 | } | |
3124 | ||
02f3fc28 PA |
3125 | /* An interesting event. */ |
3126 | gdb_assert (lp); | |
ca2163eb | 3127 | lp->status = status; |
02f3fc28 PA |
3128 | return lp; |
3129 | } | |
3130 | ||
0e5bf2a8 PA |
3131 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3132 | their exits until all other threads in the group have exited. */ | |
3133 | ||
3134 | static void | |
3135 | check_zombie_leaders (void) | |
3136 | { | |
3137 | struct inferior *inf; | |
3138 | ||
3139 | ALL_INFERIORS (inf) | |
3140 | { | |
3141 | struct lwp_info *leader_lp; | |
3142 | ||
3143 | if (inf->pid == 0) | |
3144 | continue; | |
3145 | ||
3146 | leader_lp = find_lwp_pid (pid_to_ptid (inf->pid)); | |
3147 | if (leader_lp != NULL | |
3148 | /* Check if there are other threads in the group, as we may | |
3149 | have raced with the inferior simply exiting. */ | |
3150 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3151 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3152 | { |
3153 | if (debug_linux_nat) | |
3154 | fprintf_unfiltered (gdb_stdlog, | |
3155 | "CZL: Thread group leader %d zombie " | |
3156 | "(it exited, or another thread execd).\n", | |
3157 | inf->pid); | |
3158 | ||
3159 | /* A leader zombie can mean one of two things: | |
3160 | ||
3161 | - It exited, and there's an exit status pending | |
3162 | available, or only the leader exited (not the whole | |
3163 | program). In the latter case, we can't waitpid the | |
3164 | leader's exit status until all other threads are gone. | |
3165 | ||
3166 | - There are 3 or more threads in the group, and a thread | |
3167 | other than the leader exec'd. On an exec, the Linux | |
3168 | kernel destroys all other threads (except the execing | |
3169 | one) in the thread group, and resets the execing thread's | |
3170 | tid to the tgid. No exit notification is sent for the | |
3171 | execing thread -- from the ptracer's perspective, it | |
3172 | appears as though the execing thread just vanishes. | |
3173 | Until we reap all other threads except the leader and the | |
3174 | execing thread, the leader will be zombie, and the | |
3175 | execing thread will be in `D (disc sleep)'. As soon as | |
3176 | all other threads are reaped, the execing thread changes | |
3177 | it's tid to the tgid, and the previous (zombie) leader | |
3178 | vanishes, giving place to the "new" leader. We could try | |
3179 | distinguishing the exit and exec cases, by waiting once | |
3180 | more, and seeing if something comes out, but it doesn't | |
3181 | sound useful. The previous leader _does_ go away, and | |
3182 | we'll re-add the new one once we see the exec event | |
3183 | (which is just the same as what would happen if the | |
3184 | previous leader did exit voluntarily before some other | |
3185 | thread execs). */ | |
3186 | ||
3187 | if (debug_linux_nat) | |
3188 | fprintf_unfiltered (gdb_stdlog, | |
3189 | "CZL: Thread group leader %d vanished.\n", | |
3190 | inf->pid); | |
3191 | exit_lwp (leader_lp); | |
3192 | } | |
3193 | } | |
3194 | } | |
3195 | ||
d6b0e80f | 3196 | static ptid_t |
7feb7d06 | 3197 | linux_nat_wait_1 (struct target_ops *ops, |
47608cb1 PA |
3198 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3199 | int target_options) | |
d6b0e80f | 3200 | { |
7feb7d06 | 3201 | static sigset_t prev_mask; |
4b60df3d | 3202 | enum resume_kind last_resume_kind; |
12d9289a | 3203 | struct lwp_info *lp; |
12d9289a | 3204 | int status; |
d6b0e80f | 3205 | |
01124a23 | 3206 | if (debug_linux_nat) |
b84876c2 PA |
3207 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3208 | ||
f973ed9c DJ |
3209 | /* The first time we get here after starting a new inferior, we may |
3210 | not have added it to the LWP list yet - this is the earliest | |
3211 | moment at which we know its PID. */ | |
d90e17a7 | 3212 | if (ptid_is_pid (inferior_ptid)) |
f973ed9c | 3213 | { |
27c9d204 PA |
3214 | /* Upgrade the main thread's ptid. */ |
3215 | thread_change_ptid (inferior_ptid, | |
dfd4cc63 LM |
3216 | ptid_build (ptid_get_pid (inferior_ptid), |
3217 | ptid_get_pid (inferior_ptid), 0)); | |
27c9d204 | 3218 | |
26cb8b7c | 3219 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3220 | lp->resumed = 1; |
3221 | } | |
3222 | ||
12696c10 | 3223 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3224 | block_child_signals (&prev_mask); |
d6b0e80f AC |
3225 | |
3226 | retry: | |
d90e17a7 PA |
3227 | lp = NULL; |
3228 | status = 0; | |
d6b0e80f AC |
3229 | |
3230 | /* First check if there is a LWP with a wait status pending. */ | |
0e5bf2a8 | 3231 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d6b0e80f | 3232 | { |
0e5bf2a8 | 3233 | /* Any LWP in the PTID group that's been resumed will do. */ |
d90e17a7 | 3234 | lp = iterate_over_lwps (ptid, status_callback, NULL); |
d6b0e80f AC |
3235 | if (lp) |
3236 | { | |
ca2163eb | 3237 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3238 | fprintf_unfiltered (gdb_stdlog, |
3239 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3240 | status_to_str (lp->status), |
d6b0e80f AC |
3241 | target_pid_to_str (lp->ptid)); |
3242 | } | |
d6b0e80f | 3243 | } |
dfd4cc63 | 3244 | else if (ptid_lwp_p (ptid)) |
d6b0e80f AC |
3245 | { |
3246 | if (debug_linux_nat) | |
3247 | fprintf_unfiltered (gdb_stdlog, | |
3248 | "LLW: Waiting for specific LWP %s.\n", | |
3249 | target_pid_to_str (ptid)); | |
3250 | ||
3251 | /* We have a specific LWP to check. */ | |
3252 | lp = find_lwp_pid (ptid); | |
3253 | gdb_assert (lp); | |
d6b0e80f | 3254 | |
ca2163eb | 3255 | if (debug_linux_nat && lp->status) |
d6b0e80f AC |
3256 | fprintf_unfiltered (gdb_stdlog, |
3257 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3258 | status_to_str (lp->status), |
d6b0e80f AC |
3259 | target_pid_to_str (lp->ptid)); |
3260 | ||
d90e17a7 PA |
3261 | /* We check for lp->waitstatus in addition to lp->status, |
3262 | because we can have pending process exits recorded in | |
3263 | lp->status and W_EXITCODE(0,0) == 0. We should probably have | |
3264 | an additional lp->status_p flag. */ | |
ca2163eb | 3265 | if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) |
d90e17a7 | 3266 | lp = NULL; |
d6b0e80f AC |
3267 | } |
3268 | ||
b84876c2 PA |
3269 | if (!target_can_async_p ()) |
3270 | { | |
3271 | /* Causes SIGINT to be passed on to the attached process. */ | |
3272 | set_sigint_trap (); | |
b84876c2 | 3273 | } |
d6b0e80f | 3274 | |
0e5bf2a8 | 3275 | /* But if we don't find a pending event, we'll have to wait. */ |
7feb7d06 | 3276 | |
d90e17a7 | 3277 | while (lp == NULL) |
d6b0e80f AC |
3278 | { |
3279 | pid_t lwpid; | |
3280 | ||
0e5bf2a8 PA |
3281 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3282 | quirks: | |
3283 | ||
3284 | - If the thread group leader exits while other threads in the | |
3285 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3286 | waitpid won't return an exit status until the other threads | |
3287 | in the group are reapped. | |
3288 | ||
3289 | - When a non-leader thread execs, that thread just vanishes | |
3290 | without reporting an exit (so we'd hang if we waited for it | |
3291 | explicitly in that case). The exec event is reported to | |
3292 | the TGID pid. */ | |
3293 | ||
3294 | errno = 0; | |
3295 | lwpid = my_waitpid (-1, &status, __WCLONE | WNOHANG); | |
3296 | if (lwpid == 0 || (lwpid == -1 && errno == ECHILD)) | |
3297 | lwpid = my_waitpid (-1, &status, WNOHANG); | |
3298 | ||
3299 | if (debug_linux_nat) | |
3300 | fprintf_unfiltered (gdb_stdlog, | |
3301 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3302 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3303 | |
d6b0e80f AC |
3304 | if (lwpid > 0) |
3305 | { | |
12d9289a PA |
3306 | /* If this is true, then we paused LWPs momentarily, and may |
3307 | now have pending events to handle. */ | |
3308 | int new_pending; | |
3309 | ||
d6b0e80f AC |
3310 | if (debug_linux_nat) |
3311 | { | |
3312 | fprintf_unfiltered (gdb_stdlog, | |
3313 | "LLW: waitpid %ld received %s\n", | |
3314 | (long) lwpid, status_to_str (status)); | |
3315 | } | |
3316 | ||
0e5bf2a8 | 3317 | lp = linux_nat_filter_event (lwpid, status, &new_pending); |
d90e17a7 | 3318 | |
33355866 JK |
3319 | /* STATUS is now no longer valid, use LP->STATUS instead. */ |
3320 | status = 0; | |
3321 | ||
0e5bf2a8 | 3322 | if (lp && !ptid_match (lp->ptid, ptid)) |
d6b0e80f | 3323 | { |
e3e9f5a2 PA |
3324 | gdb_assert (lp->resumed); |
3325 | ||
d90e17a7 | 3326 | if (debug_linux_nat) |
3e43a32a MS |
3327 | fprintf (stderr, |
3328 | "LWP %ld got an event %06x, leaving pending.\n", | |
33355866 | 3329 | ptid_get_lwp (lp->ptid), lp->status); |
d90e17a7 | 3330 | |
ca2163eb | 3331 | if (WIFSTOPPED (lp->status)) |
d90e17a7 | 3332 | { |
ca2163eb | 3333 | if (WSTOPSIG (lp->status) != SIGSTOP) |
d90e17a7 | 3334 | { |
e3e9f5a2 PA |
3335 | /* Cancel breakpoint hits. The breakpoint may |
3336 | be removed before we fetch events from this | |
3337 | process to report to the core. It is best | |
3338 | not to assume the moribund breakpoints | |
3339 | heuristic always handles these cases --- it | |
3340 | could be too many events go through to the | |
3341 | core before this one is handled. All-stop | |
3342 | always cancels breakpoint hits in all | |
3343 | threads. */ | |
3344 | if (non_stop | |
00390b84 | 3345 | && linux_nat_lp_status_is_event (lp) |
e3e9f5a2 PA |
3346 | && cancel_breakpoint (lp)) |
3347 | { | |
3348 | /* Throw away the SIGTRAP. */ | |
3349 | lp->status = 0; | |
3350 | ||
3351 | if (debug_linux_nat) | |
3352 | fprintf (stderr, | |
3e43a32a MS |
3353 | "LLW: LWP %ld hit a breakpoint while" |
3354 | " waiting for another process;" | |
3355 | " cancelled it\n", | |
e3e9f5a2 PA |
3356 | ptid_get_lwp (lp->ptid)); |
3357 | } | |
d90e17a7 PA |
3358 | } |
3359 | else | |
8817a6f2 | 3360 | lp->signalled = 0; |
d90e17a7 | 3361 | } |
33355866 | 3362 | else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status)) |
d90e17a7 PA |
3363 | { |
3364 | if (debug_linux_nat) | |
3e43a32a MS |
3365 | fprintf (stderr, |
3366 | "Process %ld exited while stopping LWPs\n", | |
d90e17a7 PA |
3367 | ptid_get_lwp (lp->ptid)); |
3368 | ||
3369 | /* This was the last lwp in the process. Since | |
3370 | events are serialized to GDB core, and we can't | |
3371 | report this one right now, but GDB core and the | |
3372 | other target layers will want to be notified | |
3373 | about the exit code/signal, leave the status | |
3374 | pending for the next time we're able to report | |
3375 | it. */ | |
d90e17a7 | 3376 | |
d90e17a7 PA |
3377 | /* Dead LWP's aren't expected to reported a pending |
3378 | sigstop. */ | |
3379 | lp->signalled = 0; | |
3380 | ||
3381 | /* Store the pending event in the waitstatus as | |
3382 | well, because W_EXITCODE(0,0) == 0. */ | |
ca2163eb | 3383 | store_waitstatus (&lp->waitstatus, lp->status); |
d90e17a7 PA |
3384 | } |
3385 | ||
3386 | /* Keep looking. */ | |
3387 | lp = NULL; | |
d6b0e80f AC |
3388 | } |
3389 | ||
0e5bf2a8 | 3390 | if (new_pending) |
d90e17a7 | 3391 | { |
0e5bf2a8 PA |
3392 | /* Some LWP now has a pending event. Go all the way |
3393 | back to check it. */ | |
3394 | goto retry; | |
3395 | } | |
12d9289a | 3396 | |
0e5bf2a8 PA |
3397 | if (lp) |
3398 | { | |
3399 | /* We got an event to report to the core. */ | |
3400 | break; | |
d90e17a7 | 3401 | } |
0e5bf2a8 PA |
3402 | |
3403 | /* Retry until nothing comes out of waitpid. A single | |
3404 | SIGCHLD can indicate more than one child stopped. */ | |
3405 | continue; | |
d6b0e80f AC |
3406 | } |
3407 | ||
0e5bf2a8 PA |
3408 | /* Check for zombie thread group leaders. Those can't be reaped |
3409 | until all other threads in the thread group are. */ | |
3410 | check_zombie_leaders (); | |
d6b0e80f | 3411 | |
0e5bf2a8 PA |
3412 | /* If there are no resumed children left, bail. We'd be stuck |
3413 | forever in the sigsuspend call below otherwise. */ | |
3414 | if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL) | |
3415 | { | |
3416 | if (debug_linux_nat) | |
3417 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3418 | |
0e5bf2a8 | 3419 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3420 | |
0e5bf2a8 PA |
3421 | if (!target_can_async_p ()) |
3422 | clear_sigint_trap (); | |
b84876c2 | 3423 | |
0e5bf2a8 PA |
3424 | restore_child_signals_mask (&prev_mask); |
3425 | return minus_one_ptid; | |
d6b0e80f | 3426 | } |
28736962 | 3427 | |
0e5bf2a8 PA |
3428 | /* No interesting event to report to the core. */ |
3429 | ||
3430 | if (target_options & TARGET_WNOHANG) | |
3431 | { | |
01124a23 | 3432 | if (debug_linux_nat) |
28736962 PA |
3433 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3434 | ||
0e5bf2a8 | 3435 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3436 | restore_child_signals_mask (&prev_mask); |
3437 | return minus_one_ptid; | |
3438 | } | |
d6b0e80f AC |
3439 | |
3440 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3441 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3442 | |
3443 | /* Block until we get an event reported with SIGCHLD. */ | |
3444 | sigsuspend (&suspend_mask); | |
d6b0e80f AC |
3445 | } |
3446 | ||
b84876c2 | 3447 | if (!target_can_async_p ()) |
d26b5354 | 3448 | clear_sigint_trap (); |
d6b0e80f AC |
3449 | |
3450 | gdb_assert (lp); | |
3451 | ||
ca2163eb PA |
3452 | status = lp->status; |
3453 | lp->status = 0; | |
3454 | ||
d6b0e80f AC |
3455 | /* Don't report signals that GDB isn't interested in, such as |
3456 | signals that are neither printed nor stopped upon. Stopping all | |
3457 | threads can be a bit time-consuming so if we want decent | |
3458 | performance with heavily multi-threaded programs, especially when | |
3459 | they're using a high frequency timer, we'd better avoid it if we | |
3460 | can. */ | |
3461 | ||
3462 | if (WIFSTOPPED (status)) | |
3463 | { | |
2ea28649 | 3464 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); |
d6b0e80f | 3465 | |
2455069d UW |
3466 | /* When using hardware single-step, we need to report every signal. |
3467 | Otherwise, signals in pass_mask may be short-circuited. */ | |
d539ed7e | 3468 | if (!lp->step |
2455069d | 3469 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))) |
d6b0e80f AC |
3470 | { |
3471 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
3472 | here? It is not clear we should. GDB may not expect | |
3473 | other threads to run. On the other hand, not resuming | |
3474 | newly attached threads may cause an unwanted delay in | |
3475 | getting them running. */ | |
3476 | registers_changed (); | |
7b50312a PA |
3477 | if (linux_nat_prepare_to_resume != NULL) |
3478 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 LM |
3479 | linux_ops->to_resume (linux_ops, |
3480 | pid_to_ptid (ptid_get_lwp (lp->ptid)), | |
10d6c8cd | 3481 | lp->step, signo); |
d6b0e80f AC |
3482 | if (debug_linux_nat) |
3483 | fprintf_unfiltered (gdb_stdlog, | |
3484 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3485 | lp->step ? | |
3486 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
3487 | target_pid_to_str (lp->ptid), | |
a493e3e2 | 3488 | (signo != GDB_SIGNAL_0 |
2ea28649 | 3489 | ? strsignal (gdb_signal_to_host (signo)) |
423ec54c | 3490 | : "0")); |
d6b0e80f | 3491 | lp->stopped = 0; |
d6b0e80f AC |
3492 | goto retry; |
3493 | } | |
3494 | ||
1ad15515 | 3495 | if (!non_stop) |
d6b0e80f | 3496 | { |
1ad15515 PA |
3497 | /* Only do the below in all-stop, as we currently use SIGINT |
3498 | to implement target_stop (see linux_nat_stop) in | |
3499 | non-stop. */ | |
a493e3e2 | 3500 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) |
1ad15515 PA |
3501 | { |
3502 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3503 | forwarded to the entire process group, that is, all LWPs | |
3504 | will receive it - unless they're using CLONE_THREAD to | |
3505 | share signals. Since we only want to report it once, we | |
3506 | mark it as ignored for all LWPs except this one. */ | |
d90e17a7 PA |
3507 | iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)), |
3508 | set_ignore_sigint, NULL); | |
1ad15515 PA |
3509 | lp->ignore_sigint = 0; |
3510 | } | |
3511 | else | |
3512 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
3513 | } |
3514 | } | |
3515 | ||
3516 | /* This LWP is stopped now. */ | |
3517 | lp->stopped = 1; | |
3518 | ||
3519 | if (debug_linux_nat) | |
3520 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
3521 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
3522 | ||
4c28f408 PA |
3523 | if (!non_stop) |
3524 | { | |
3525 | /* Now stop all other LWP's ... */ | |
d90e17a7 | 3526 | iterate_over_lwps (minus_one_ptid, stop_callback, NULL); |
4c28f408 PA |
3527 | |
3528 | /* ... and wait until all of them have reported back that | |
3529 | they're no longer running. */ | |
d90e17a7 | 3530 | iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL); |
4c28f408 PA |
3531 | |
3532 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3533 | from among those that have had events. Giving equal priority | |
3534 | to all LWPs that have had events helps prevent | |
3535 | starvation. */ | |
0e5bf2a8 | 3536 | if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid)) |
d90e17a7 | 3537 | select_event_lwp (ptid, &lp, &status); |
d6b0e80f | 3538 | |
e3e9f5a2 PA |
3539 | /* Now that we've selected our final event LWP, cancel any |
3540 | breakpoints in other LWPs that have hit a GDB breakpoint. | |
3541 | See the comment in cancel_breakpoints_callback to find out | |
3542 | why. */ | |
3543 | iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp); | |
3544 | ||
4b60df3d PA |
3545 | /* We'll need this to determine whether to report a SIGSTOP as |
3546 | TARGET_WAITKIND_0. Need to take a copy because | |
3547 | resume_clear_callback clears it. */ | |
3548 | last_resume_kind = lp->last_resume_kind; | |
3549 | ||
e3e9f5a2 PA |
3550 | /* In all-stop, from the core's perspective, all LWPs are now |
3551 | stopped until a new resume action is sent over. */ | |
3552 | iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL); | |
3553 | } | |
3554 | else | |
25289eb2 | 3555 | { |
4b60df3d PA |
3556 | /* See above. */ |
3557 | last_resume_kind = lp->last_resume_kind; | |
3558 | resume_clear_callback (lp, NULL); | |
25289eb2 | 3559 | } |
d6b0e80f | 3560 | |
26ab7092 | 3561 | if (linux_nat_status_is_event (status)) |
d6b0e80f | 3562 | { |
d6b0e80f AC |
3563 | if (debug_linux_nat) |
3564 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
3565 | "LLW: trap ptid is %s.\n", |
3566 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 3567 | } |
d6b0e80f AC |
3568 | |
3569 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3570 | { | |
3571 | *ourstatus = lp->waitstatus; | |
3572 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3573 | } | |
3574 | else | |
3575 | store_waitstatus (ourstatus, status); | |
3576 | ||
01124a23 | 3577 | if (debug_linux_nat) |
b84876c2 PA |
3578 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3579 | ||
7feb7d06 | 3580 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3581 | |
4b60df3d | 3582 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3583 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3584 | && WSTOPSIG (status) == SIGSTOP) | |
3585 | { | |
3586 | /* A thread that has been requested to stop by GDB with | |
3587 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3588 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3589 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3590 | } |
3591 | ||
1e225492 JK |
3592 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3593 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3594 | lp->core = -1; | |
3595 | else | |
2e794194 | 3596 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3597 | |
f973ed9c | 3598 | return lp->ptid; |
d6b0e80f AC |
3599 | } |
3600 | ||
e3e9f5a2 PA |
3601 | /* Resume LWPs that are currently stopped without any pending status |
3602 | to report, but are resumed from the core's perspective. */ | |
3603 | ||
3604 | static int | |
3605 | resume_stopped_resumed_lwps (struct lwp_info *lp, void *data) | |
3606 | { | |
3607 | ptid_t *wait_ptid_p = data; | |
3608 | ||
3609 | if (lp->stopped | |
3610 | && lp->resumed | |
3611 | && lp->status == 0 | |
3612 | && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE) | |
3613 | { | |
336060f3 PA |
3614 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
3615 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
3616 | CORE_ADDR pc = regcache_read_pc (regcache); | |
3617 | ||
e3e9f5a2 PA |
3618 | gdb_assert (is_executing (lp->ptid)); |
3619 | ||
3620 | /* Don't bother if there's a breakpoint at PC that we'd hit | |
3621 | immediately, and we're not waiting for this LWP. */ | |
3622 | if (!ptid_match (lp->ptid, *wait_ptid_p)) | |
3623 | { | |
e3e9f5a2 PA |
3624 | if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc)) |
3625 | return 0; | |
3626 | } | |
3627 | ||
3628 | if (debug_linux_nat) | |
3629 | fprintf_unfiltered (gdb_stdlog, | |
336060f3 PA |
3630 | "RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", |
3631 | target_pid_to_str (lp->ptid), | |
3632 | paddress (gdbarch, pc), | |
3633 | lp->step); | |
e3e9f5a2 | 3634 | |
336060f3 | 3635 | registers_changed (); |
7b50312a PA |
3636 | if (linux_nat_prepare_to_resume != NULL) |
3637 | linux_nat_prepare_to_resume (lp); | |
dfd4cc63 | 3638 | linux_ops->to_resume (linux_ops, pid_to_ptid (ptid_get_lwp (lp->ptid)), |
a493e3e2 | 3639 | lp->step, GDB_SIGNAL_0); |
e3e9f5a2 | 3640 | lp->stopped = 0; |
e3e9f5a2 PA |
3641 | lp->stopped_by_watchpoint = 0; |
3642 | } | |
3643 | ||
3644 | return 0; | |
3645 | } | |
3646 | ||
7feb7d06 PA |
3647 | static ptid_t |
3648 | linux_nat_wait (struct target_ops *ops, | |
47608cb1 PA |
3649 | ptid_t ptid, struct target_waitstatus *ourstatus, |
3650 | int target_options) | |
7feb7d06 PA |
3651 | { |
3652 | ptid_t event_ptid; | |
3653 | ||
3654 | if (debug_linux_nat) | |
09826ec5 PA |
3655 | { |
3656 | char *options_string; | |
3657 | ||
3658 | options_string = target_options_to_string (target_options); | |
3659 | fprintf_unfiltered (gdb_stdlog, | |
3660 | "linux_nat_wait: [%s], [%s]\n", | |
3661 | target_pid_to_str (ptid), | |
3662 | options_string); | |
3663 | xfree (options_string); | |
3664 | } | |
7feb7d06 PA |
3665 | |
3666 | /* Flush the async file first. */ | |
3667 | if (target_can_async_p ()) | |
3668 | async_file_flush (); | |
3669 | ||
e3e9f5a2 PA |
3670 | /* Resume LWPs that are currently stopped without any pending status |
3671 | to report, but are resumed from the core's perspective. LWPs get | |
3672 | in this state if we find them stopping at a time we're not | |
3673 | interested in reporting the event (target_wait on a | |
3674 | specific_process, for example, see linux_nat_wait_1), and | |
3675 | meanwhile the event became uninteresting. Don't bother resuming | |
3676 | LWPs we're not going to wait for if they'd stop immediately. */ | |
3677 | if (non_stop) | |
3678 | iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid); | |
3679 | ||
47608cb1 | 3680 | event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options); |
7feb7d06 PA |
3681 | |
3682 | /* If we requested any event, and something came out, assume there | |
3683 | may be more. If we requested a specific lwp or process, also | |
3684 | assume there may be more. */ | |
3685 | if (target_can_async_p () | |
6953d224 PA |
3686 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3687 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
7feb7d06 PA |
3688 | || !ptid_equal (ptid, minus_one_ptid))) |
3689 | async_file_mark (); | |
3690 | ||
3691 | /* Get ready for the next event. */ | |
3692 | if (target_can_async_p ()) | |
3693 | target_async (inferior_event_handler, 0); | |
3694 | ||
3695 | return event_ptid; | |
3696 | } | |
3697 | ||
d6b0e80f AC |
3698 | static int |
3699 | kill_callback (struct lwp_info *lp, void *data) | |
3700 | { | |
ed731959 JK |
3701 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3702 | ||
3703 | errno = 0; | |
69ff6be5 | 3704 | kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL); |
ed731959 | 3705 | if (debug_linux_nat) |
57745c90 PA |
3706 | { |
3707 | int save_errno = errno; | |
3708 | ||
3709 | fprintf_unfiltered (gdb_stdlog, | |
3710 | "KC: kill (SIGKILL) %s, 0, 0 (%s)\n", | |
3711 | target_pid_to_str (lp->ptid), | |
3712 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3713 | } | |
ed731959 JK |
3714 | |
3715 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3716 | ||
d6b0e80f | 3717 | errno = 0; |
dfd4cc63 | 3718 | ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0); |
d6b0e80f | 3719 | if (debug_linux_nat) |
57745c90 PA |
3720 | { |
3721 | int save_errno = errno; | |
3722 | ||
3723 | fprintf_unfiltered (gdb_stdlog, | |
3724 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3725 | target_pid_to_str (lp->ptid), | |
3726 | save_errno ? safe_strerror (save_errno) : "OK"); | |
3727 | } | |
d6b0e80f AC |
3728 | |
3729 | return 0; | |
3730 | } | |
3731 | ||
3732 | static int | |
3733 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3734 | { | |
3735 | pid_t pid; | |
3736 | ||
3737 | /* We must make sure that there are no pending events (delayed | |
3738 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3739 | program doesn't interfere with any following debugging session. */ | |
3740 | ||
3741 | /* For cloned processes we must check both with __WCLONE and | |
3742 | without, since the exit status of a cloned process isn't reported | |
3743 | with __WCLONE. */ | |
3744 | if (lp->cloned) | |
3745 | { | |
3746 | do | |
3747 | { | |
dfd4cc63 | 3748 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, __WCLONE); |
e85a822c | 3749 | if (pid != (pid_t) -1) |
d6b0e80f | 3750 | { |
e85a822c DJ |
3751 | if (debug_linux_nat) |
3752 | fprintf_unfiltered (gdb_stdlog, | |
3753 | "KWC: wait %s received unknown.\n", | |
3754 | target_pid_to_str (lp->ptid)); | |
3755 | /* The Linux kernel sometimes fails to kill a thread | |
3756 | completely after PTRACE_KILL; that goes from the stop | |
3757 | point in do_fork out to the one in | |
3758 | get_signal_to_deliever and waits again. So kill it | |
3759 | again. */ | |
3760 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3761 | } |
3762 | } | |
dfd4cc63 | 3763 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3764 | |
3765 | gdb_assert (pid == -1 && errno == ECHILD); | |
3766 | } | |
3767 | ||
3768 | do | |
3769 | { | |
dfd4cc63 | 3770 | pid = my_waitpid (ptid_get_lwp (lp->ptid), NULL, 0); |
e85a822c | 3771 | if (pid != (pid_t) -1) |
d6b0e80f | 3772 | { |
e85a822c DJ |
3773 | if (debug_linux_nat) |
3774 | fprintf_unfiltered (gdb_stdlog, | |
3775 | "KWC: wait %s received unk.\n", | |
3776 | target_pid_to_str (lp->ptid)); | |
3777 | /* See the call to kill_callback above. */ | |
3778 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3779 | } |
3780 | } | |
dfd4cc63 | 3781 | while (pid == ptid_get_lwp (lp->ptid)); |
d6b0e80f AC |
3782 | |
3783 | gdb_assert (pid == -1 && errno == ECHILD); | |
3784 | return 0; | |
3785 | } | |
3786 | ||
3787 | static void | |
7d85a9c0 | 3788 | linux_nat_kill (struct target_ops *ops) |
d6b0e80f | 3789 | { |
f973ed9c DJ |
3790 | struct target_waitstatus last; |
3791 | ptid_t last_ptid; | |
3792 | int status; | |
d6b0e80f | 3793 | |
f973ed9c DJ |
3794 | /* If we're stopped while forking and we haven't followed yet, |
3795 | kill the other task. We need to do this first because the | |
3796 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3797 | |
f973ed9c | 3798 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3799 | |
f973ed9c DJ |
3800 | if (last.kind == TARGET_WAITKIND_FORKED |
3801 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3802 | { | |
dfd4cc63 | 3803 | ptrace (PT_KILL, ptid_get_pid (last.value.related_pid), 0, 0); |
f973ed9c | 3804 | wait (&status); |
26cb8b7c PA |
3805 | |
3806 | /* Let the arch-specific native code know this process is | |
3807 | gone. */ | |
dfd4cc63 | 3808 | linux_nat_forget_process (ptid_get_pid (last.value.related_pid)); |
f973ed9c DJ |
3809 | } |
3810 | ||
3811 | if (forks_exist_p ()) | |
7feb7d06 | 3812 | linux_fork_killall (); |
f973ed9c DJ |
3813 | else |
3814 | { | |
d90e17a7 | 3815 | ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid)); |
e0881a8e | 3816 | |
4c28f408 PA |
3817 | /* Stop all threads before killing them, since ptrace requires |
3818 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d90e17a7 | 3819 | iterate_over_lwps (ptid, stop_callback, NULL); |
4c28f408 PA |
3820 | /* ... and wait until all of them have reported back that |
3821 | they're no longer running. */ | |
d90e17a7 | 3822 | iterate_over_lwps (ptid, stop_wait_callback, NULL); |
4c28f408 | 3823 | |
f973ed9c | 3824 | /* Kill all LWP's ... */ |
d90e17a7 | 3825 | iterate_over_lwps (ptid, kill_callback, NULL); |
f973ed9c DJ |
3826 | |
3827 | /* ... and wait until we've flushed all events. */ | |
d90e17a7 | 3828 | iterate_over_lwps (ptid, kill_wait_callback, NULL); |
f973ed9c DJ |
3829 | } |
3830 | ||
3831 | target_mourn_inferior (); | |
d6b0e80f AC |
3832 | } |
3833 | ||
3834 | static void | |
136d6dae | 3835 | linux_nat_mourn_inferior (struct target_ops *ops) |
d6b0e80f | 3836 | { |
26cb8b7c PA |
3837 | int pid = ptid_get_pid (inferior_ptid); |
3838 | ||
3839 | purge_lwp_list (pid); | |
d6b0e80f | 3840 | |
f973ed9c | 3841 | if (! forks_exist_p ()) |
d90e17a7 PA |
3842 | /* Normal case, no other forks available. */ |
3843 | linux_ops->to_mourn_inferior (ops); | |
f973ed9c DJ |
3844 | else |
3845 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3846 | there are other viable forks to debug. Delete the exiting | |
3847 | one and context-switch to the first available. */ | |
3848 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3849 | |
3850 | /* Let the arch-specific native code know this process is gone. */ | |
3851 | linux_nat_forget_process (pid); | |
d6b0e80f AC |
3852 | } |
3853 | ||
5b009018 PA |
3854 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3855 | layout of the inferiors' architecture. */ | |
3856 | ||
3857 | static void | |
a5362b9a | 3858 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 PA |
3859 | { |
3860 | int done = 0; | |
3861 | ||
3862 | if (linux_nat_siginfo_fixup != NULL) | |
3863 | done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction); | |
3864 | ||
3865 | /* If there was no callback, or the callback didn't do anything, | |
3866 | then just do a straight memcpy. */ | |
3867 | if (!done) | |
3868 | { | |
3869 | if (direction == 1) | |
a5362b9a | 3870 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3871 | else |
a5362b9a | 3872 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3873 | } |
3874 | } | |
3875 | ||
9b409511 | 3876 | static enum target_xfer_status |
4aa995e1 PA |
3877 | linux_xfer_siginfo (struct target_ops *ops, enum target_object object, |
3878 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
3879 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3880 | ULONGEST *xfered_len) | |
4aa995e1 | 3881 | { |
4aa995e1 | 3882 | int pid; |
a5362b9a TS |
3883 | siginfo_t siginfo; |
3884 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3885 | |
3886 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3887 | gdb_assert (readbuf || writebuf); | |
3888 | ||
dfd4cc63 | 3889 | pid = ptid_get_lwp (inferior_ptid); |
4aa995e1 | 3890 | if (pid == 0) |
dfd4cc63 | 3891 | pid = ptid_get_pid (inferior_ptid); |
4aa995e1 PA |
3892 | |
3893 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3894 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3895 | |
3896 | errno = 0; | |
3897 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3898 | if (errno != 0) | |
2ed4b548 | 3899 | return TARGET_XFER_E_IO; |
4aa995e1 | 3900 | |
5b009018 PA |
3901 | /* When GDB is built as a 64-bit application, ptrace writes into |
3902 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3903 | inferior with a 64-bit GDB should look the same as debugging it | |
3904 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3905 | the converted layout, so any read/write will have to be done | |
3906 | post-conversion. */ | |
3907 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3908 | ||
4aa995e1 PA |
3909 | if (offset + len > sizeof (siginfo)) |
3910 | len = sizeof (siginfo) - offset; | |
3911 | ||
3912 | if (readbuf != NULL) | |
5b009018 | 3913 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3914 | else |
3915 | { | |
5b009018 PA |
3916 | memcpy (inf_siginfo + offset, writebuf, len); |
3917 | ||
3918 | /* Convert back to ptrace layout before flushing it out. */ | |
3919 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3920 | ||
4aa995e1 PA |
3921 | errno = 0; |
3922 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3923 | if (errno != 0) | |
2ed4b548 | 3924 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3925 | } |
3926 | ||
9b409511 YQ |
3927 | *xfered_len = len; |
3928 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3929 | } |
3930 | ||
9b409511 | 3931 | static enum target_xfer_status |
10d6c8cd DJ |
3932 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, |
3933 | const char *annex, gdb_byte *readbuf, | |
3934 | const gdb_byte *writebuf, | |
9b409511 | 3935 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
d6b0e80f | 3936 | { |
4aa995e1 | 3937 | struct cleanup *old_chain; |
9b409511 | 3938 | enum target_xfer_status xfer; |
d6b0e80f | 3939 | |
4aa995e1 PA |
3940 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
3941 | return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf, | |
9b409511 | 3942 | offset, len, xfered_len); |
4aa995e1 | 3943 | |
c35b1492 PA |
3944 | /* The target is connected but no live inferior is selected. Pass |
3945 | this request down to a lower stratum (e.g., the executable | |
3946 | file). */ | |
3947 | if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid)) | |
9b409511 | 3948 | return TARGET_XFER_EOF; |
c35b1492 | 3949 | |
4aa995e1 PA |
3950 | old_chain = save_inferior_ptid (); |
3951 | ||
dfd4cc63 LM |
3952 | if (ptid_lwp_p (inferior_ptid)) |
3953 | inferior_ptid = pid_to_ptid (ptid_get_lwp (inferior_ptid)); | |
d6b0e80f | 3954 | |
10d6c8cd | 3955 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 | 3956 | offset, len, xfered_len); |
d6b0e80f AC |
3957 | |
3958 | do_cleanups (old_chain); | |
3959 | return xfer; | |
3960 | } | |
3961 | ||
3962 | static int | |
28439f5e | 3963 | linux_thread_alive (ptid_t ptid) |
d6b0e80f | 3964 | { |
8c6a60d1 | 3965 | int err, tmp_errno; |
4c28f408 | 3966 | |
dfd4cc63 | 3967 | gdb_assert (ptid_lwp_p (ptid)); |
d6b0e80f | 3968 | |
4c28f408 PA |
3969 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3970 | running thread errors out claiming that the thread doesn't | |
3971 | exist. */ | |
dfd4cc63 | 3972 | err = kill_lwp (ptid_get_lwp (ptid), 0); |
8c6a60d1 | 3973 | tmp_errno = errno; |
d6b0e80f AC |
3974 | if (debug_linux_nat) |
3975 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3976 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3977 | target_pid_to_str (ptid), |
8c6a60d1 | 3978 | err ? safe_strerror (tmp_errno) : "OK"); |
9c0dd46b | 3979 | |
4c28f408 | 3980 | if (err != 0) |
d6b0e80f AC |
3981 | return 0; |
3982 | ||
3983 | return 1; | |
3984 | } | |
3985 | ||
28439f5e PA |
3986 | static int |
3987 | linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid) | |
3988 | { | |
3989 | return linux_thread_alive (ptid); | |
3990 | } | |
3991 | ||
d6b0e80f | 3992 | static char * |
117de6a9 | 3993 | linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid) |
d6b0e80f AC |
3994 | { |
3995 | static char buf[64]; | |
3996 | ||
dfd4cc63 LM |
3997 | if (ptid_lwp_p (ptid) |
3998 | && (ptid_get_pid (ptid) != ptid_get_lwp (ptid) | |
3999 | || num_lwps (ptid_get_pid (ptid)) > 1)) | |
d6b0e80f | 4000 | { |
dfd4cc63 | 4001 | snprintf (buf, sizeof (buf), "LWP %ld", ptid_get_lwp (ptid)); |
d6b0e80f AC |
4002 | return buf; |
4003 | } | |
4004 | ||
4005 | return normal_pid_to_str (ptid); | |
4006 | } | |
4007 | ||
4694da01 | 4008 | static char * |
503a628d | 4009 | linux_nat_thread_name (struct target_ops *self, struct thread_info *thr) |
4694da01 TT |
4010 | { |
4011 | int pid = ptid_get_pid (thr->ptid); | |
4012 | long lwp = ptid_get_lwp (thr->ptid); | |
4013 | #define FORMAT "/proc/%d/task/%ld/comm" | |
4014 | char buf[sizeof (FORMAT) + 30]; | |
4015 | FILE *comm_file; | |
4016 | char *result = NULL; | |
4017 | ||
4018 | snprintf (buf, sizeof (buf), FORMAT, pid, lwp); | |
614c279d | 4019 | comm_file = gdb_fopen_cloexec (buf, "r"); |
4694da01 TT |
4020 | if (comm_file) |
4021 | { | |
4022 | /* Not exported by the kernel, so we define it here. */ | |
4023 | #define COMM_LEN 16 | |
4024 | static char line[COMM_LEN + 1]; | |
4025 | ||
4026 | if (fgets (line, sizeof (line), comm_file)) | |
4027 | { | |
4028 | char *nl = strchr (line, '\n'); | |
4029 | ||
4030 | if (nl) | |
4031 | *nl = '\0'; | |
4032 | if (*line != '\0') | |
4033 | result = line; | |
4034 | } | |
4035 | ||
4036 | fclose (comm_file); | |
4037 | } | |
4038 | ||
4039 | #undef COMM_LEN | |
4040 | #undef FORMAT | |
4041 | ||
4042 | return result; | |
4043 | } | |
4044 | ||
dba24537 AC |
4045 | /* Accepts an integer PID; Returns a string representing a file that |
4046 | can be opened to get the symbols for the child process. */ | |
4047 | ||
6d8fd2b7 | 4048 | static char * |
8dd27370 | 4049 | linux_child_pid_to_exec_file (struct target_ops *self, int pid) |
dba24537 | 4050 | { |
b4ab256d HZ |
4051 | static char buf[PATH_MAX]; |
4052 | char name[PATH_MAX]; | |
dba24537 | 4053 | |
b4ab256d HZ |
4054 | xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid); |
4055 | memset (buf, 0, PATH_MAX); | |
4056 | if (readlink (name, buf, PATH_MAX - 1) <= 0) | |
4057 | strcpy (buf, name); | |
dba24537 | 4058 | |
b4ab256d | 4059 | return buf; |
dba24537 AC |
4060 | } |
4061 | ||
dba24537 AC |
4062 | /* Records the thread's register state for the corefile note |
4063 | section. */ | |
4064 | ||
4065 | static char * | |
6432734d UW |
4066 | linux_nat_collect_thread_registers (const struct regcache *regcache, |
4067 | ptid_t ptid, bfd *obfd, | |
4068 | char *note_data, int *note_size, | |
2ea28649 | 4069 | enum gdb_signal stop_signal) |
dba24537 | 4070 | { |
6432734d | 4071 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
4f844a66 | 4072 | const struct regset *regset; |
55e969c1 | 4073 | int core_regset_p; |
6432734d UW |
4074 | gdb_gregset_t gregs; |
4075 | gdb_fpregset_t fpregs; | |
4f844a66 DM |
4076 | |
4077 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
dba24537 | 4078 | |
6432734d UW |
4079 | if (core_regset_p |
4080 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
4081 | sizeof (gregs))) | |
4082 | != NULL && regset->collect_regset != NULL) | |
4083 | regset->collect_regset (regset, regcache, -1, &gregs, sizeof (gregs)); | |
4f844a66 | 4084 | else |
6432734d | 4085 | fill_gregset (regcache, &gregs, -1); |
2f2241f1 | 4086 | |
6432734d UW |
4087 | note_data = (char *) elfcore_write_prstatus |
4088 | (obfd, note_data, note_size, ptid_get_lwp (ptid), | |
2ea28649 | 4089 | gdb_signal_to_host (stop_signal), &gregs); |
2f2241f1 | 4090 | |
6432734d UW |
4091 | if (core_regset_p |
4092 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
4093 | sizeof (fpregs))) | |
3e43a32a | 4094 | != NULL && regset->collect_regset != NULL) |
6432734d UW |
4095 | regset->collect_regset (regset, regcache, -1, &fpregs, sizeof (fpregs)); |
4096 | else | |
4097 | fill_fpregset (regcache, &fpregs, -1); | |
17ea7499 | 4098 | |
6432734d UW |
4099 | note_data = (char *) elfcore_write_prfpreg (obfd, note_data, note_size, |
4100 | &fpregs, sizeof (fpregs)); | |
4f844a66 | 4101 | |
dba24537 AC |
4102 | return note_data; |
4103 | } | |
4104 | ||
dba24537 AC |
4105 | /* Fills the "to_make_corefile_note" target vector. Builds the note |
4106 | section for a corefile, and returns it in a malloc buffer. */ | |
4107 | ||
4108 | static char * | |
fc6691b2 TT |
4109 | linux_nat_make_corefile_notes (struct target_ops *self, |
4110 | bfd *obfd, int *note_size) | |
dba24537 | 4111 | { |
6432734d UW |
4112 | /* FIXME: uweigand/2011-10-06: Once all GNU/Linux architectures have been |
4113 | converted to gdbarch_core_regset_sections, this function can go away. */ | |
f5656ead | 4114 | return linux_make_corefile_notes (target_gdbarch (), obfd, note_size, |
6432734d | 4115 | linux_nat_collect_thread_registers); |
dba24537 AC |
4116 | } |
4117 | ||
10d6c8cd DJ |
4118 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
4119 | filesystem. Because we can use a single read() call for /proc, this | |
4120 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
4121 | but it doesn't support writes. */ | |
4122 | ||
9b409511 | 4123 | static enum target_xfer_status |
10d6c8cd DJ |
4124 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, |
4125 | const char *annex, gdb_byte *readbuf, | |
4126 | const gdb_byte *writebuf, | |
9b409511 | 4127 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 4128 | { |
10d6c8cd DJ |
4129 | LONGEST ret; |
4130 | int fd; | |
dba24537 AC |
4131 | char filename[64]; |
4132 | ||
10d6c8cd | 4133 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
4134 | return 0; |
4135 | ||
4136 | /* Don't bother for one word. */ | |
4137 | if (len < 3 * sizeof (long)) | |
9b409511 | 4138 | return TARGET_XFER_EOF; |
dba24537 AC |
4139 | |
4140 | /* We could keep this file open and cache it - possibly one per | |
4141 | thread. That requires some juggling, but is even faster. */ | |
cde33bf1 YQ |
4142 | xsnprintf (filename, sizeof filename, "/proc/%d/mem", |
4143 | ptid_get_pid (inferior_ptid)); | |
614c279d | 4144 | fd = gdb_open_cloexec (filename, O_RDONLY | O_LARGEFILE, 0); |
dba24537 | 4145 | if (fd == -1) |
9b409511 | 4146 | return TARGET_XFER_EOF; |
dba24537 AC |
4147 | |
4148 | /* If pread64 is available, use it. It's faster if the kernel | |
4149 | supports it (only one syscall), and it's 64-bit safe even on | |
4150 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
4151 | application). */ | |
4152 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 4153 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 4154 | #else |
10d6c8cd | 4155 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
4156 | #endif |
4157 | ret = 0; | |
4158 | else | |
4159 | ret = len; | |
4160 | ||
4161 | close (fd); | |
9b409511 YQ |
4162 | |
4163 | if (ret == 0) | |
4164 | return TARGET_XFER_EOF; | |
4165 | else | |
4166 | { | |
4167 | *xfered_len = ret; | |
4168 | return TARGET_XFER_OK; | |
4169 | } | |
dba24537 AC |
4170 | } |
4171 | ||
efcbbd14 UW |
4172 | |
4173 | /* Enumerate spufs IDs for process PID. */ | |
4174 | static LONGEST | |
b55e14c7 | 4175 | spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, ULONGEST len) |
efcbbd14 | 4176 | { |
f5656ead | 4177 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
efcbbd14 UW |
4178 | LONGEST pos = 0; |
4179 | LONGEST written = 0; | |
4180 | char path[128]; | |
4181 | DIR *dir; | |
4182 | struct dirent *entry; | |
4183 | ||
4184 | xsnprintf (path, sizeof path, "/proc/%d/fd", pid); | |
4185 | dir = opendir (path); | |
4186 | if (!dir) | |
4187 | return -1; | |
4188 | ||
4189 | rewinddir (dir); | |
4190 | while ((entry = readdir (dir)) != NULL) | |
4191 | { | |
4192 | struct stat st; | |
4193 | struct statfs stfs; | |
4194 | int fd; | |
4195 | ||
4196 | fd = atoi (entry->d_name); | |
4197 | if (!fd) | |
4198 | continue; | |
4199 | ||
4200 | xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd); | |
4201 | if (stat (path, &st) != 0) | |
4202 | continue; | |
4203 | if (!S_ISDIR (st.st_mode)) | |
4204 | continue; | |
4205 | ||
4206 | if (statfs (path, &stfs) != 0) | |
4207 | continue; | |
4208 | if (stfs.f_type != SPUFS_MAGIC) | |
4209 | continue; | |
4210 | ||
4211 | if (pos >= offset && pos + 4 <= offset + len) | |
4212 | { | |
4213 | store_unsigned_integer (buf + pos - offset, 4, byte_order, fd); | |
4214 | written += 4; | |
4215 | } | |
4216 | pos += 4; | |
4217 | } | |
4218 | ||
4219 | closedir (dir); | |
4220 | return written; | |
4221 | } | |
4222 | ||
4223 | /* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
4224 | object type, using the /proc file system. */ | |
9b409511 YQ |
4225 | |
4226 | static enum target_xfer_status | |
efcbbd14 UW |
4227 | linux_proc_xfer_spu (struct target_ops *ops, enum target_object object, |
4228 | const char *annex, gdb_byte *readbuf, | |
4229 | const gdb_byte *writebuf, | |
9b409511 | 4230 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
efcbbd14 UW |
4231 | { |
4232 | char buf[128]; | |
4233 | int fd = 0; | |
4234 | int ret = -1; | |
dfd4cc63 | 4235 | int pid = ptid_get_pid (inferior_ptid); |
efcbbd14 UW |
4236 | |
4237 | if (!annex) | |
4238 | { | |
4239 | if (!readbuf) | |
2ed4b548 | 4240 | return TARGET_XFER_E_IO; |
efcbbd14 | 4241 | else |
9b409511 YQ |
4242 | { |
4243 | LONGEST l = spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
4244 | ||
4245 | if (l < 0) | |
4246 | return TARGET_XFER_E_IO; | |
4247 | else if (l == 0) | |
4248 | return TARGET_XFER_EOF; | |
4249 | else | |
4250 | { | |
4251 | *xfered_len = (ULONGEST) l; | |
4252 | return TARGET_XFER_OK; | |
4253 | } | |
4254 | } | |
efcbbd14 UW |
4255 | } |
4256 | ||
4257 | xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex); | |
614c279d | 4258 | fd = gdb_open_cloexec (buf, writebuf? O_WRONLY : O_RDONLY, 0); |
efcbbd14 | 4259 | if (fd <= 0) |
2ed4b548 | 4260 | return TARGET_XFER_E_IO; |
efcbbd14 UW |
4261 | |
4262 | if (offset != 0 | |
4263 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
4264 | { | |
4265 | close (fd); | |
9b409511 | 4266 | return TARGET_XFER_EOF; |
efcbbd14 UW |
4267 | } |
4268 | ||
4269 | if (writebuf) | |
4270 | ret = write (fd, writebuf, (size_t) len); | |
4271 | else if (readbuf) | |
4272 | ret = read (fd, readbuf, (size_t) len); | |
4273 | ||
4274 | close (fd); | |
9b409511 YQ |
4275 | |
4276 | if (ret < 0) | |
4277 | return TARGET_XFER_E_IO; | |
4278 | else if (ret == 0) | |
4279 | return TARGET_XFER_EOF; | |
4280 | else | |
4281 | { | |
4282 | *xfered_len = (ULONGEST) ret; | |
4283 | return TARGET_XFER_OK; | |
4284 | } | |
efcbbd14 UW |
4285 | } |
4286 | ||
4287 | ||
dba24537 AC |
4288 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4289 | ||
4290 | static void | |
4291 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4292 | { | |
4293 | int len = strlen (line) - 1; | |
4294 | const char *p; | |
4295 | int signum; | |
4296 | ||
4297 | if (line[len] != '\n') | |
8a3fe4f8 | 4298 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4299 | |
4300 | p = line; | |
4301 | signum = len * 4; | |
4302 | while (len-- > 0) | |
4303 | { | |
4304 | int digit; | |
4305 | ||
4306 | if (*p >= '0' && *p <= '9') | |
4307 | digit = *p - '0'; | |
4308 | else if (*p >= 'a' && *p <= 'f') | |
4309 | digit = *p - 'a' + 10; | |
4310 | else | |
8a3fe4f8 | 4311 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4312 | |
4313 | signum -= 4; | |
4314 | ||
4315 | if (digit & 1) | |
4316 | sigaddset (sigs, signum + 1); | |
4317 | if (digit & 2) | |
4318 | sigaddset (sigs, signum + 2); | |
4319 | if (digit & 4) | |
4320 | sigaddset (sigs, signum + 3); | |
4321 | if (digit & 8) | |
4322 | sigaddset (sigs, signum + 4); | |
4323 | ||
4324 | p++; | |
4325 | } | |
4326 | } | |
4327 | ||
4328 | /* Find process PID's pending signals from /proc/pid/status and set | |
4329 | SIGS to match. */ | |
4330 | ||
4331 | void | |
3e43a32a MS |
4332 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4333 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 AC |
4334 | { |
4335 | FILE *procfile; | |
d8d2a3ee | 4336 | char buffer[PATH_MAX], fname[PATH_MAX]; |
7c8a8b04 | 4337 | struct cleanup *cleanup; |
dba24537 AC |
4338 | |
4339 | sigemptyset (pending); | |
4340 | sigemptyset (blocked); | |
4341 | sigemptyset (ignored); | |
cde33bf1 | 4342 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
614c279d | 4343 | procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4344 | if (procfile == NULL) |
8a3fe4f8 | 4345 | error (_("Could not open %s"), fname); |
7c8a8b04 | 4346 | cleanup = make_cleanup_fclose (procfile); |
dba24537 | 4347 | |
d8d2a3ee | 4348 | while (fgets (buffer, PATH_MAX, procfile) != NULL) |
dba24537 AC |
4349 | { |
4350 | /* Normal queued signals are on the SigPnd line in the status | |
4351 | file. However, 2.6 kernels also have a "shared" pending | |
4352 | queue for delivering signals to a thread group, so check for | |
4353 | a ShdPnd line also. | |
4354 | ||
4355 | Unfortunately some Red Hat kernels include the shared pending | |
4356 | queue but not the ShdPnd status field. */ | |
4357 | ||
4358 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
4359 | add_line_to_sigset (buffer + 8, pending); | |
4360 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
4361 | add_line_to_sigset (buffer + 8, pending); | |
4362 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
4363 | add_line_to_sigset (buffer + 8, blocked); | |
4364 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
4365 | add_line_to_sigset (buffer + 8, ignored); | |
4366 | } | |
4367 | ||
7c8a8b04 | 4368 | do_cleanups (cleanup); |
dba24537 AC |
4369 | } |
4370 | ||
9b409511 | 4371 | static enum target_xfer_status |
07e059b5 | 4372 | linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object, |
e0881a8e | 4373 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4374 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4375 | ULONGEST *xfered_len) | |
07e059b5 | 4376 | { |
07e059b5 VP |
4377 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4378 | ||
9b409511 YQ |
4379 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4380 | if (*xfered_len == 0) | |
4381 | return TARGET_XFER_EOF; | |
4382 | else | |
4383 | return TARGET_XFER_OK; | |
07e059b5 VP |
4384 | } |
4385 | ||
9b409511 | 4386 | static enum target_xfer_status |
10d6c8cd DJ |
4387 | linux_xfer_partial (struct target_ops *ops, enum target_object object, |
4388 | const char *annex, gdb_byte *readbuf, | |
9b409511 YQ |
4389 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4390 | ULONGEST *xfered_len) | |
10d6c8cd | 4391 | { |
9b409511 | 4392 | enum target_xfer_status xfer; |
10d6c8cd DJ |
4393 | |
4394 | if (object == TARGET_OBJECT_AUXV) | |
9f2982ff | 4395 | return memory_xfer_auxv (ops, object, annex, readbuf, writebuf, |
9b409511 | 4396 | offset, len, xfered_len); |
10d6c8cd | 4397 | |
07e059b5 VP |
4398 | if (object == TARGET_OBJECT_OSDATA) |
4399 | return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4400 | offset, len, xfered_len); |
07e059b5 | 4401 | |
efcbbd14 UW |
4402 | if (object == TARGET_OBJECT_SPU) |
4403 | return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4404 | offset, len, xfered_len); |
efcbbd14 | 4405 | |
8f313923 JK |
4406 | /* GDB calculates all the addresses in possibly larget width of the address. |
4407 | Address width needs to be masked before its final use - either by | |
4408 | linux_proc_xfer_partial or inf_ptrace_xfer_partial. | |
4409 | ||
4410 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
4411 | ||
4412 | if (object == TARGET_OBJECT_MEMORY) | |
4413 | { | |
f5656ead | 4414 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
8f313923 JK |
4415 | |
4416 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
4417 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
4418 | } | |
4419 | ||
10d6c8cd | 4420 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, |
9b409511 YQ |
4421 | offset, len, xfered_len); |
4422 | if (xfer != TARGET_XFER_EOF) | |
10d6c8cd DJ |
4423 | return xfer; |
4424 | ||
4425 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
9b409511 | 4426 | offset, len, xfered_len); |
10d6c8cd DJ |
4427 | } |
4428 | ||
5808517f YQ |
4429 | static void |
4430 | cleanup_target_stop (void *arg) | |
4431 | { | |
4432 | ptid_t *ptid = (ptid_t *) arg; | |
4433 | ||
4434 | gdb_assert (arg != NULL); | |
4435 | ||
4436 | /* Unpause all */ | |
a493e3e2 | 4437 | target_resume (*ptid, 0, GDB_SIGNAL_0); |
5808517f YQ |
4438 | } |
4439 | ||
4440 | static VEC(static_tracepoint_marker_p) * | |
c686c57f TT |
4441 | linux_child_static_tracepoint_markers_by_strid (struct target_ops *self, |
4442 | const char *strid) | |
5808517f YQ |
4443 | { |
4444 | char s[IPA_CMD_BUF_SIZE]; | |
4445 | struct cleanup *old_chain; | |
4446 | int pid = ptid_get_pid (inferior_ptid); | |
4447 | VEC(static_tracepoint_marker_p) *markers = NULL; | |
4448 | struct static_tracepoint_marker *marker = NULL; | |
4449 | char *p = s; | |
4450 | ptid_t ptid = ptid_build (pid, 0, 0); | |
4451 | ||
4452 | /* Pause all */ | |
4453 | target_stop (ptid); | |
4454 | ||
4455 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4456 | s[sizeof ("qTfSTM")] = 0; | |
4457 | ||
42476b70 | 4458 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4459 | |
4460 | old_chain = make_cleanup (free_current_marker, &marker); | |
4461 | make_cleanup (cleanup_target_stop, &ptid); | |
4462 | ||
4463 | while (*p++ == 'm') | |
4464 | { | |
4465 | if (marker == NULL) | |
4466 | marker = XCNEW (struct static_tracepoint_marker); | |
4467 | ||
4468 | do | |
4469 | { | |
4470 | parse_static_tracepoint_marker_definition (p, &p, marker); | |
4471 | ||
4472 | if (strid == NULL || strcmp (strid, marker->str_id) == 0) | |
4473 | { | |
4474 | VEC_safe_push (static_tracepoint_marker_p, | |
4475 | markers, marker); | |
4476 | marker = NULL; | |
4477 | } | |
4478 | else | |
4479 | { | |
4480 | release_static_tracepoint_marker (marker); | |
4481 | memset (marker, 0, sizeof (*marker)); | |
4482 | } | |
4483 | } | |
4484 | while (*p++ == ','); /* comma-separated list */ | |
4485 | ||
4486 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4487 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4488 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4489 | p = s; |
4490 | } | |
4491 | ||
4492 | do_cleanups (old_chain); | |
4493 | ||
4494 | return markers; | |
4495 | } | |
4496 | ||
e9efe249 | 4497 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
4498 | it with local methods. */ |
4499 | ||
910122bf UW |
4500 | static void |
4501 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 4502 | { |
6d8fd2b7 | 4503 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
eb73ad13 | 4504 | t->to_remove_fork_catchpoint = linux_child_remove_fork_catchpoint; |
6d8fd2b7 | 4505 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; |
eb73ad13 | 4506 | t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint; |
6d8fd2b7 | 4507 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; |
eb73ad13 | 4508 | t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint; |
a96d9b2e | 4509 | t->to_set_syscall_catchpoint = linux_child_set_syscall_catchpoint; |
6d8fd2b7 | 4510 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; |
10d6c8cd | 4511 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
4512 | t->to_post_attach = linux_child_post_attach; |
4513 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
4514 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; |
4515 | ||
4516 | super_xfer_partial = t->to_xfer_partial; | |
4517 | t->to_xfer_partial = linux_xfer_partial; | |
5808517f YQ |
4518 | |
4519 | t->to_static_tracepoint_markers_by_strid | |
4520 | = linux_child_static_tracepoint_markers_by_strid; | |
910122bf UW |
4521 | } |
4522 | ||
4523 | struct target_ops * | |
4524 | linux_target (void) | |
4525 | { | |
4526 | struct target_ops *t; | |
4527 | ||
4528 | t = inf_ptrace_target (); | |
4529 | linux_target_install_ops (t); | |
4530 | ||
4531 | return t; | |
4532 | } | |
4533 | ||
4534 | struct target_ops * | |
7714d83a | 4535 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
4536 | { |
4537 | struct target_ops *t; | |
4538 | ||
4539 | t = inf_ptrace_trad_target (register_u_offset); | |
4540 | linux_target_install_ops (t); | |
10d6c8cd | 4541 | |
10d6c8cd DJ |
4542 | return t; |
4543 | } | |
4544 | ||
b84876c2 PA |
4545 | /* target_is_async_p implementation. */ |
4546 | ||
4547 | static int | |
6a109b6b | 4548 | linux_nat_is_async_p (struct target_ops *ops) |
b84876c2 PA |
4549 | { |
4550 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4551 | it explicitly with the "set target-async" command. |
b84876c2 | 4552 | Someday, linux will always be async. */ |
3dd5b83d | 4553 | return target_async_permitted; |
b84876c2 PA |
4554 | } |
4555 | ||
4556 | /* target_can_async_p implementation. */ | |
4557 | ||
4558 | static int | |
6a109b6b | 4559 | linux_nat_can_async_p (struct target_ops *ops) |
b84876c2 PA |
4560 | { |
4561 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
7feb7d06 | 4562 | it explicitly with the "set target-async" command. |
b84876c2 | 4563 | Someday, linux will always be async. */ |
3dd5b83d | 4564 | return target_async_permitted; |
b84876c2 PA |
4565 | } |
4566 | ||
9908b566 | 4567 | static int |
2a9a2795 | 4568 | linux_nat_supports_non_stop (struct target_ops *self) |
9908b566 VP |
4569 | { |
4570 | return 1; | |
4571 | } | |
4572 | ||
d90e17a7 PA |
4573 | /* True if we want to support multi-process. To be removed when GDB |
4574 | supports multi-exec. */ | |
4575 | ||
2277426b | 4576 | int linux_multi_process = 1; |
d90e17a7 PA |
4577 | |
4578 | static int | |
86ce2668 | 4579 | linux_nat_supports_multi_process (struct target_ops *self) |
d90e17a7 PA |
4580 | { |
4581 | return linux_multi_process; | |
4582 | } | |
4583 | ||
03583c20 | 4584 | static int |
2bfc0540 | 4585 | linux_nat_supports_disable_randomization (struct target_ops *self) |
03583c20 UW |
4586 | { |
4587 | #ifdef HAVE_PERSONALITY | |
4588 | return 1; | |
4589 | #else | |
4590 | return 0; | |
4591 | #endif | |
4592 | } | |
4593 | ||
b84876c2 PA |
4594 | static int async_terminal_is_ours = 1; |
4595 | ||
4d4ca2a1 DE |
4596 | /* target_terminal_inferior implementation. |
4597 | ||
4598 | This is a wrapper around child_terminal_inferior to add async support. */ | |
b84876c2 PA |
4599 | |
4600 | static void | |
d2f640d4 | 4601 | linux_nat_terminal_inferior (struct target_ops *self) |
b84876c2 PA |
4602 | { |
4603 | if (!target_is_async_p ()) | |
4604 | { | |
4605 | /* Async mode is disabled. */ | |
d6b64346 | 4606 | child_terminal_inferior (self); |
b84876c2 PA |
4607 | return; |
4608 | } | |
4609 | ||
d6b64346 | 4610 | child_terminal_inferior (self); |
b84876c2 | 4611 | |
d9d2d8b6 | 4612 | /* Calls to target_terminal_*() are meant to be idempotent. */ |
b84876c2 PA |
4613 | if (!async_terminal_is_ours) |
4614 | return; | |
4615 | ||
4616 | delete_file_handler (input_fd); | |
4617 | async_terminal_is_ours = 0; | |
4618 | set_sigint_trap (); | |
4619 | } | |
4620 | ||
4d4ca2a1 DE |
4621 | /* target_terminal_ours implementation. |
4622 | ||
4623 | This is a wrapper around child_terminal_ours to add async support (and | |
4624 | implement the target_terminal_ours vs target_terminal_ours_for_output | |
4625 | distinction). child_terminal_ours is currently no different than | |
4626 | child_terminal_ours_for_output. | |
4627 | We leave target_terminal_ours_for_output alone, leaving it to | |
4628 | child_terminal_ours_for_output. */ | |
b84876c2 | 4629 | |
2c0b251b | 4630 | static void |
e3594fd1 | 4631 | linux_nat_terminal_ours (struct target_ops *self) |
b84876c2 PA |
4632 | { |
4633 | if (!target_is_async_p ()) | |
4634 | { | |
4635 | /* Async mode is disabled. */ | |
d6b64346 | 4636 | child_terminal_ours (self); |
b84876c2 PA |
4637 | return; |
4638 | } | |
4639 | ||
4640 | /* GDB should never give the terminal to the inferior if the | |
4641 | inferior is running in the background (run&, continue&, etc.), | |
4642 | but claiming it sure should. */ | |
d6b64346 | 4643 | child_terminal_ours (self); |
b84876c2 | 4644 | |
b84876c2 PA |
4645 | if (async_terminal_is_ours) |
4646 | return; | |
4647 | ||
4648 | clear_sigint_trap (); | |
4649 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4650 | async_terminal_is_ours = 1; | |
4651 | } | |
4652 | ||
4653 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4654 | void *context); | |
4655 | static void *async_client_context; | |
4656 | ||
7feb7d06 PA |
4657 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4658 | so we notice when any child changes state, and notify the | |
4659 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4660 | above to wait for the arrival of a SIGCHLD. */ | |
4661 | ||
b84876c2 | 4662 | static void |
7feb7d06 | 4663 | sigchld_handler (int signo) |
b84876c2 | 4664 | { |
7feb7d06 PA |
4665 | int old_errno = errno; |
4666 | ||
01124a23 DE |
4667 | if (debug_linux_nat) |
4668 | ui_file_write_async_safe (gdb_stdlog, | |
4669 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4670 | |
4671 | if (signo == SIGCHLD | |
4672 | && linux_nat_event_pipe[0] != -1) | |
4673 | async_file_mark (); /* Let the event loop know that there are | |
4674 | events to handle. */ | |
4675 | ||
4676 | errno = old_errno; | |
4677 | } | |
4678 | ||
4679 | /* Callback registered with the target events file descriptor. */ | |
4680 | ||
4681 | static void | |
4682 | handle_target_event (int error, gdb_client_data client_data) | |
4683 | { | |
4684 | (*async_client_callback) (INF_REG_EVENT, async_client_context); | |
4685 | } | |
4686 | ||
4687 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4688 | ||
4689 | static int | |
4690 | linux_async_pipe (int enable) | |
4691 | { | |
4692 | int previous = (linux_nat_event_pipe[0] != -1); | |
4693 | ||
4694 | if (previous != enable) | |
4695 | { | |
4696 | sigset_t prev_mask; | |
4697 | ||
12696c10 PA |
4698 | /* Block child signals while we create/destroy the pipe, as |
4699 | their handler writes to it. */ | |
7feb7d06 PA |
4700 | block_child_signals (&prev_mask); |
4701 | ||
4702 | if (enable) | |
4703 | { | |
614c279d | 4704 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4705 | internal_error (__FILE__, __LINE__, |
4706 | "creating event pipe failed."); | |
4707 | ||
4708 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4709 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4710 | } | |
4711 | else | |
4712 | { | |
4713 | close (linux_nat_event_pipe[0]); | |
4714 | close (linux_nat_event_pipe[1]); | |
4715 | linux_nat_event_pipe[0] = -1; | |
4716 | linux_nat_event_pipe[1] = -1; | |
4717 | } | |
4718 | ||
4719 | restore_child_signals_mask (&prev_mask); | |
4720 | } | |
4721 | ||
4722 | return previous; | |
b84876c2 PA |
4723 | } |
4724 | ||
4725 | /* target_async implementation. */ | |
4726 | ||
4727 | static void | |
6a109b6b TT |
4728 | linux_nat_async (struct target_ops *ops, |
4729 | void (*callback) (enum inferior_event_type event_type, | |
4730 | void *context), | |
4731 | void *context) | |
b84876c2 | 4732 | { |
b84876c2 PA |
4733 | if (callback != NULL) |
4734 | { | |
4735 | async_client_callback = callback; | |
4736 | async_client_context = context; | |
7feb7d06 PA |
4737 | if (!linux_async_pipe (1)) |
4738 | { | |
4739 | add_file_handler (linux_nat_event_pipe[0], | |
4740 | handle_target_event, NULL); | |
4741 | /* There may be pending events to handle. Tell the event loop | |
4742 | to poll them. */ | |
4743 | async_file_mark (); | |
4744 | } | |
b84876c2 PA |
4745 | } |
4746 | else | |
4747 | { | |
4748 | async_client_callback = callback; | |
4749 | async_client_context = context; | |
b84876c2 | 4750 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4751 | linux_async_pipe (0); |
b84876c2 PA |
4752 | } |
4753 | return; | |
4754 | } | |
4755 | ||
a493e3e2 | 4756 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4757 | event came out. */ |
4758 | ||
4c28f408 | 4759 | static int |
252fbfc8 | 4760 | linux_nat_stop_lwp (struct lwp_info *lwp, void *data) |
4c28f408 | 4761 | { |
d90e17a7 | 4762 | if (!lwp->stopped) |
252fbfc8 | 4763 | { |
d90e17a7 PA |
4764 | if (debug_linux_nat) |
4765 | fprintf_unfiltered (gdb_stdlog, | |
4766 | "LNSL: running -> suspending %s\n", | |
4767 | target_pid_to_str (lwp->ptid)); | |
252fbfc8 | 4768 | |
252fbfc8 | 4769 | |
25289eb2 PA |
4770 | if (lwp->last_resume_kind == resume_stop) |
4771 | { | |
4772 | if (debug_linux_nat) | |
4773 | fprintf_unfiltered (gdb_stdlog, | |
4774 | "linux-nat: already stopping LWP %ld at " | |
4775 | "GDB's request\n", | |
4776 | ptid_get_lwp (lwp->ptid)); | |
4777 | return 0; | |
4778 | } | |
252fbfc8 | 4779 | |
25289eb2 PA |
4780 | stop_callback (lwp, NULL); |
4781 | lwp->last_resume_kind = resume_stop; | |
d90e17a7 PA |
4782 | } |
4783 | else | |
4784 | { | |
4785 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4786 | |
d90e17a7 PA |
4787 | if (debug_linux_nat) |
4788 | { | |
e09875d4 | 4789 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4790 | fprintf_unfiltered (gdb_stdlog, |
4791 | "LNSL: already stopped/stop_requested %s\n", | |
d90e17a7 PA |
4792 | target_pid_to_str (lwp->ptid)); |
4793 | else | |
3e43a32a MS |
4794 | fprintf_unfiltered (gdb_stdlog, |
4795 | "LNSL: already stopped/no " | |
4796 | "stop_requested yet %s\n", | |
d90e17a7 | 4797 | target_pid_to_str (lwp->ptid)); |
252fbfc8 PA |
4798 | } |
4799 | } | |
4c28f408 PA |
4800 | return 0; |
4801 | } | |
4802 | ||
4803 | static void | |
1eab8a48 | 4804 | linux_nat_stop (struct target_ops *self, ptid_t ptid) |
4c28f408 PA |
4805 | { |
4806 | if (non_stop) | |
d90e17a7 | 4807 | iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL); |
4c28f408 | 4808 | else |
1eab8a48 | 4809 | linux_ops->to_stop (linux_ops, ptid); |
4c28f408 PA |
4810 | } |
4811 | ||
d90e17a7 | 4812 | static void |
de90e03d | 4813 | linux_nat_close (struct target_ops *self) |
d90e17a7 PA |
4814 | { |
4815 | /* Unregister from the event loop. */ | |
9debeba0 DE |
4816 | if (linux_nat_is_async_p (self)) |
4817 | linux_nat_async (self, NULL, NULL); | |
d90e17a7 | 4818 | |
d90e17a7 | 4819 | if (linux_ops->to_close) |
de90e03d | 4820 | linux_ops->to_close (linux_ops); |
6a3cb8e8 PA |
4821 | |
4822 | super_close (self); | |
d90e17a7 PA |
4823 | } |
4824 | ||
c0694254 PA |
4825 | /* When requests are passed down from the linux-nat layer to the |
4826 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4827 | used. The address space pointer is stored in the inferior object, | |
4828 | but the common code that is passed such ptid can't tell whether | |
4829 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4830 | look up the "main" process id from the lwp here. */ | |
4831 | ||
70221824 | 4832 | static struct address_space * |
c0694254 PA |
4833 | linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid) |
4834 | { | |
4835 | struct lwp_info *lwp; | |
4836 | struct inferior *inf; | |
4837 | int pid; | |
4838 | ||
dfd4cc63 | 4839 | if (ptid_get_lwp (ptid) == 0) |
c0694254 PA |
4840 | { |
4841 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4842 | tgid. */ | |
4843 | lwp = find_lwp_pid (ptid); | |
dfd4cc63 | 4844 | pid = ptid_get_pid (lwp->ptid); |
c0694254 PA |
4845 | } |
4846 | else | |
4847 | { | |
4848 | /* A (pid,lwpid,0) ptid. */ | |
dfd4cc63 | 4849 | pid = ptid_get_pid (ptid); |
c0694254 PA |
4850 | } |
4851 | ||
4852 | inf = find_inferior_pid (pid); | |
4853 | gdb_assert (inf != NULL); | |
4854 | return inf->aspace; | |
4855 | } | |
4856 | ||
dc146f7c VP |
4857 | /* Return the cached value of the processor core for thread PTID. */ |
4858 | ||
70221824 | 4859 | static int |
dc146f7c VP |
4860 | linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid) |
4861 | { | |
4862 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4863 | |
dc146f7c VP |
4864 | if (info) |
4865 | return info->core; | |
4866 | return -1; | |
4867 | } | |
4868 | ||
f973ed9c DJ |
4869 | void |
4870 | linux_nat_add_target (struct target_ops *t) | |
4871 | { | |
f973ed9c DJ |
4872 | /* Save the provided single-threaded target. We save this in a separate |
4873 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4874 | may have saved a pointer to T; we want to use it for the final | |
4875 | process stratum target. */ | |
4876 | linux_ops_saved = *t; | |
4877 | linux_ops = &linux_ops_saved; | |
4878 | ||
4879 | /* Override some methods for multithreading. */ | |
b84876c2 | 4880 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4881 | t->to_attach = linux_nat_attach; |
4882 | t->to_detach = linux_nat_detach; | |
4883 | t->to_resume = linux_nat_resume; | |
4884 | t->to_wait = linux_nat_wait; | |
2455069d | 4885 | t->to_pass_signals = linux_nat_pass_signals; |
f973ed9c DJ |
4886 | t->to_xfer_partial = linux_nat_xfer_partial; |
4887 | t->to_kill = linux_nat_kill; | |
4888 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4889 | t->to_thread_alive = linux_nat_thread_alive; | |
4890 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4694da01 | 4891 | t->to_thread_name = linux_nat_thread_name; |
f973ed9c | 4892 | t->to_has_thread_control = tc_schedlock; |
c0694254 | 4893 | t->to_thread_address_space = linux_nat_thread_address_space; |
ebec9a0f PA |
4894 | t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint; |
4895 | t->to_stopped_data_address = linux_nat_stopped_data_address; | |
f973ed9c | 4896 | |
b84876c2 PA |
4897 | t->to_can_async_p = linux_nat_can_async_p; |
4898 | t->to_is_async_p = linux_nat_is_async_p; | |
9908b566 | 4899 | t->to_supports_non_stop = linux_nat_supports_non_stop; |
b84876c2 | 4900 | t->to_async = linux_nat_async; |
b84876c2 PA |
4901 | t->to_terminal_inferior = linux_nat_terminal_inferior; |
4902 | t->to_terminal_ours = linux_nat_terminal_ours; | |
6a3cb8e8 PA |
4903 | |
4904 | super_close = t->to_close; | |
d90e17a7 | 4905 | t->to_close = linux_nat_close; |
b84876c2 | 4906 | |
4c28f408 PA |
4907 | /* Methods for non-stop support. */ |
4908 | t->to_stop = linux_nat_stop; | |
4909 | ||
d90e17a7 PA |
4910 | t->to_supports_multi_process = linux_nat_supports_multi_process; |
4911 | ||
03583c20 UW |
4912 | t->to_supports_disable_randomization |
4913 | = linux_nat_supports_disable_randomization; | |
4914 | ||
dc146f7c VP |
4915 | t->to_core_of_thread = linux_nat_core_of_thread; |
4916 | ||
f973ed9c DJ |
4917 | /* We don't change the stratum; this target will sit at |
4918 | process_stratum and thread_db will set at thread_stratum. This | |
4919 | is a little strange, since this is a multi-threaded-capable | |
4920 | target, but we want to be on the stack below thread_db, and we | |
4921 | also want to be used for single-threaded processes. */ | |
4922 | ||
4923 | add_target (t); | |
f973ed9c DJ |
4924 | } |
4925 | ||
9f0bdab8 DJ |
4926 | /* Register a method to call whenever a new thread is attached. */ |
4927 | void | |
7b50312a PA |
4928 | linux_nat_set_new_thread (struct target_ops *t, |
4929 | void (*new_thread) (struct lwp_info *)) | |
9f0bdab8 DJ |
4930 | { |
4931 | /* Save the pointer. We only support a single registered instance | |
4932 | of the GNU/Linux native target, so we do not need to map this to | |
4933 | T. */ | |
4934 | linux_nat_new_thread = new_thread; | |
4935 | } | |
4936 | ||
26cb8b7c PA |
4937 | /* See declaration in linux-nat.h. */ |
4938 | ||
4939 | void | |
4940 | linux_nat_set_new_fork (struct target_ops *t, | |
4941 | linux_nat_new_fork_ftype *new_fork) | |
4942 | { | |
4943 | /* Save the pointer. */ | |
4944 | linux_nat_new_fork = new_fork; | |
4945 | } | |
4946 | ||
4947 | /* See declaration in linux-nat.h. */ | |
4948 | ||
4949 | void | |
4950 | linux_nat_set_forget_process (struct target_ops *t, | |
4951 | linux_nat_forget_process_ftype *fn) | |
4952 | { | |
4953 | /* Save the pointer. */ | |
4954 | linux_nat_forget_process_hook = fn; | |
4955 | } | |
4956 | ||
4957 | /* See declaration in linux-nat.h. */ | |
4958 | ||
4959 | void | |
4960 | linux_nat_forget_process (pid_t pid) | |
4961 | { | |
4962 | if (linux_nat_forget_process_hook != NULL) | |
4963 | linux_nat_forget_process_hook (pid); | |
4964 | } | |
4965 | ||
5b009018 PA |
4966 | /* Register a method that converts a siginfo object between the layout |
4967 | that ptrace returns, and the layout in the architecture of the | |
4968 | inferior. */ | |
4969 | void | |
4970 | linux_nat_set_siginfo_fixup (struct target_ops *t, | |
a5362b9a | 4971 | int (*siginfo_fixup) (siginfo_t *, |
5b009018 PA |
4972 | gdb_byte *, |
4973 | int)) | |
4974 | { | |
4975 | /* Save the pointer. */ | |
4976 | linux_nat_siginfo_fixup = siginfo_fixup; | |
4977 | } | |
4978 | ||
7b50312a PA |
4979 | /* Register a method to call prior to resuming a thread. */ |
4980 | ||
4981 | void | |
4982 | linux_nat_set_prepare_to_resume (struct target_ops *t, | |
4983 | void (*prepare_to_resume) (struct lwp_info *)) | |
4984 | { | |
4985 | /* Save the pointer. */ | |
4986 | linux_nat_prepare_to_resume = prepare_to_resume; | |
4987 | } | |
4988 | ||
f865ee35 JK |
4989 | /* See linux-nat.h. */ |
4990 | ||
4991 | int | |
4992 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4993 | { |
da559b09 | 4994 | int pid; |
9f0bdab8 | 4995 | |
dfd4cc63 | 4996 | pid = ptid_get_lwp (ptid); |
da559b09 | 4997 | if (pid == 0) |
dfd4cc63 | 4998 | pid = ptid_get_pid (ptid); |
f865ee35 | 4999 | |
da559b09 JK |
5000 | errno = 0; |
5001 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
5002 | if (errno != 0) | |
5003 | { | |
5004 | memset (siginfo, 0, sizeof (*siginfo)); | |
5005 | return 0; | |
5006 | } | |
f865ee35 | 5007 | return 1; |
9f0bdab8 DJ |
5008 | } |
5009 | ||
2c0b251b PA |
5010 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
5011 | extern initialize_file_ftype _initialize_linux_nat; | |
5012 | ||
d6b0e80f AC |
5013 | void |
5014 | _initialize_linux_nat (void) | |
5015 | { | |
ccce17b0 YQ |
5016 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
5017 | &debug_linux_nat, _("\ | |
b84876c2 PA |
5018 | Set debugging of GNU/Linux lwp module."), _("\ |
5019 | Show debugging of GNU/Linux lwp module."), _("\ | |
5020 | Enables printf debugging output."), | |
ccce17b0 YQ |
5021 | NULL, |
5022 | show_debug_linux_nat, | |
5023 | &setdebuglist, &showdebuglist); | |
b84876c2 | 5024 | |
b84876c2 | 5025 | /* Save this mask as the default. */ |
d6b0e80f AC |
5026 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
5027 | ||
7feb7d06 PA |
5028 | /* Install a SIGCHLD handler. */ |
5029 | sigchld_action.sa_handler = sigchld_handler; | |
5030 | sigemptyset (&sigchld_action.sa_mask); | |
5031 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
5032 | |
5033 | /* Make it the default. */ | |
7feb7d06 | 5034 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
5035 | |
5036 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
5037 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
5038 | sigdelset (&suspend_mask, SIGCHLD); | |
5039 | ||
7feb7d06 | 5040 | sigemptyset (&blocked_mask); |
8009206a TT |
5041 | |
5042 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to | |
5043 | support read-only process state. */ | |
5044 | linux_ptrace_set_additional_flags (PTRACE_O_TRACESYSGOOD | |
5045 | | PTRACE_O_TRACEVFORKDONE | |
5046 | | PTRACE_O_TRACEVFORK | |
5047 | | PTRACE_O_TRACEFORK | |
5048 | | PTRACE_O_TRACEEXEC); | |
d6b0e80f AC |
5049 | } |
5050 | \f | |
5051 | ||
5052 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
5053 | the GNU/Linux Threads library and therefore doesn't really belong | |
5054 | here. */ | |
5055 | ||
5056 | /* Read variable NAME in the target and return its value if found. | |
5057 | Otherwise return zero. It is assumed that the type of the variable | |
5058 | is `int'. */ | |
5059 | ||
5060 | static int | |
5061 | get_signo (const char *name) | |
5062 | { | |
3b7344d5 | 5063 | struct bound_minimal_symbol ms; |
d6b0e80f AC |
5064 | int signo; |
5065 | ||
5066 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
3b7344d5 | 5067 | if (ms.minsym == NULL) |
d6b0e80f AC |
5068 | return 0; |
5069 | ||
77e371c0 | 5070 | if (target_read_memory (BMSYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
5071 | sizeof (signo)) != 0) |
5072 | return 0; | |
5073 | ||
5074 | return signo; | |
5075 | } | |
5076 | ||
5077 | /* Return the set of signals used by the threads library in *SET. */ | |
5078 | ||
5079 | void | |
5080 | lin_thread_get_thread_signals (sigset_t *set) | |
5081 | { | |
5082 | struct sigaction action; | |
5083 | int restart, cancel; | |
5084 | ||
b84876c2 | 5085 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
5086 | sigemptyset (set); |
5087 | ||
5088 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
5089 | cancel = get_signo ("__pthread_sig_cancel"); |
5090 | ||
5091 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
5092 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
5093 | not provide any way for the debugger to query the signal numbers - | |
5094 | fortunately they don't change! */ | |
5095 | ||
d6b0e80f | 5096 | if (restart == 0) |
17fbb0bd | 5097 | restart = __SIGRTMIN; |
d6b0e80f | 5098 | |
d6b0e80f | 5099 | if (cancel == 0) |
17fbb0bd | 5100 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
5101 | |
5102 | sigaddset (set, restart); | |
5103 | sigaddset (set, cancel); | |
5104 | ||
5105 | /* The GNU/Linux Threads library makes terminating threads send a | |
5106 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
5107 | those (to prevent them from terminating GDB itself, which is | |
5108 | likely to be their default action) and treat them the same way as | |
5109 | SIGCHLD. */ | |
5110 | ||
5111 | action.sa_handler = sigchld_handler; | |
5112 | sigemptyset (&action.sa_mask); | |
58aecb61 | 5113 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
5114 | sigaction (cancel, &action, NULL); |
5115 | ||
5116 | /* We block the "cancel" signal throughout this code ... */ | |
5117 | sigaddset (&blocked_mask, cancel); | |
5118 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
5119 | ||
5120 | /* ... except during a sigsuspend. */ | |
5121 | sigdelset (&suspend_mask, cancel); | |
5122 | } |