Commit | Line | Data |
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3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
9b254dd1 | 3 | Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
e26af52f | 4 | Free Software Foundation, Inc. |
3993f6b1 DJ |
5 | |
6 | This file is part of GDB. | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 10 | the Free Software Foundation; either version 3 of the License, or |
3993f6b1 DJ |
11 | (at your option) any later version. |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3993f6b1 DJ |
20 | |
21 | #include "defs.h" | |
22 | #include "inferior.h" | |
23 | #include "target.h" | |
d6b0e80f | 24 | #include "gdb_string.h" |
3993f6b1 | 25 | #include "gdb_wait.h" |
d6b0e80f AC |
26 | #include "gdb_assert.h" |
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" |
ac264b3b | 33 | #include "linux-fork.h" |
d6b0e80f AC |
34 | #include "gdbthread.h" |
35 | #include "gdbcmd.h" | |
36 | #include "regcache.h" | |
4f844a66 | 37 | #include "regset.h" |
10d6c8cd DJ |
38 | #include "inf-ptrace.h" |
39 | #include "auxv.h" | |
dba24537 AC |
40 | #include <sys/param.h> /* for MAXPATHLEN */ |
41 | #include <sys/procfs.h> /* for elf_gregset etc. */ | |
42 | #include "elf-bfd.h" /* for elfcore_write_* */ | |
43 | #include "gregset.h" /* for gregset */ | |
44 | #include "gdbcore.h" /* for get_exec_file */ | |
45 | #include <ctype.h> /* for isdigit */ | |
46 | #include "gdbthread.h" /* for struct thread_info etc. */ | |
47 | #include "gdb_stat.h" /* for struct stat */ | |
48 | #include <fcntl.h> /* for O_RDONLY */ | |
b84876c2 PA |
49 | #include "inf-loop.h" |
50 | #include "event-loop.h" | |
51 | #include "event-top.h" | |
dba24537 | 52 | |
10568435 JK |
53 | #ifdef HAVE_PERSONALITY |
54 | # include <sys/personality.h> | |
55 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
56 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
57 | # endif | |
58 | #endif /* HAVE_PERSONALITY */ | |
59 | ||
8a77dff3 VP |
60 | /* This comment documents high-level logic of this file. |
61 | ||
62 | Waiting for events in sync mode | |
63 | =============================== | |
64 | ||
65 | When waiting for an event in a specific thread, we just use waitpid, passing | |
66 | the specific pid, and not passing WNOHANG. | |
67 | ||
68 | When waiting for an event in all threads, waitpid is not quite good. Prior to | |
69 | version 2.4, Linux can either wait for event in main thread, or in secondary | |
70 | threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might | |
71 | miss an event. The solution is to use non-blocking waitpid, together with | |
72 | sigsuspend. First, we use non-blocking waitpid to get an event in the main | |
73 | process, if any. Second, we use non-blocking waitpid with the __WCLONED | |
74 | flag to check for events in cloned processes. If nothing is found, we use | |
75 | sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something | |
76 | happened to a child process -- and SIGCHLD will be delivered both for events | |
77 | in main debugged process and in cloned processes. As soon as we know there's | |
78 | an event, we get back to calling nonblocking waitpid with and without __WCLONED. | |
79 | ||
80 | Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, | |
81 | so that we don't miss a signal. If SIGCHLD arrives in between, when it's | |
82 | blocked, the signal becomes pending and sigsuspend immediately | |
83 | notices it and returns. | |
84 | ||
85 | Waiting for events in async mode | |
86 | ================================ | |
87 | ||
88 | In async mode, GDB should always be ready to handle both user input and target | |
89 | events, so neither blocking waitpid nor sigsuspend are viable | |
90 | options. Instead, we should notify the GDB main event loop whenever there's | |
91 | unprocessed event from the target. The only way to notify this event loop is | |
92 | to make it wait on input from a pipe, and write something to the pipe whenever | |
93 | there's event. Obviously, if we fail to notify the event loop if there's | |
94 | target event, it's bad. If we notify the event loop when there's no event | |
95 | from target, linux-nat.c will detect that there's no event, actually, and | |
96 | report event of type TARGET_WAITKIND_IGNORE, but it will waste time and | |
97 | better avoided. | |
98 | ||
99 | The main design point is that every time GDB is outside linux-nat.c, we have a | |
100 | SIGCHLD handler installed that is called when something happens to the target | |
101 | and notifies the GDB event loop. Also, the event is extracted from the target | |
102 | using waitpid and stored for future use. Whenever GDB core decides to handle | |
103 | the event, and calls into linux-nat.c, we disable SIGCHLD and process things | |
104 | as in sync mode, except that before waitpid call we check if there are any | |
105 | previously read events. | |
106 | ||
107 | It could happen that during event processing, we'll try to get more events | |
108 | than there are events in the local queue, which will result to waitpid call. | |
109 | Those waitpid calls, while blocking, are guarantied to always have | |
110 | something for waitpid to return. E.g., stopping a thread with SIGSTOP, and | |
111 | waiting for the lwp to stop. | |
112 | ||
113 | The event loop is notified about new events using a pipe. SIGCHLD handler does | |
114 | waitpid and writes the results in to a pipe. GDB event loop has the other end | |
115 | of the pipe among the sources. When event loop starts to process the event | |
116 | and calls a function in linux-nat.c, all events from the pipe are transferred | |
117 | into a local queue and SIGCHLD is blocked. Further processing goes as in sync | |
118 | mode. Before we return from linux_nat_wait, we transfer all unprocessed events | |
119 | from local queue back to the pipe, so that when we get back to event loop, | |
120 | event loop will notice there's something more to do. | |
121 | ||
122 | SIGCHLD is blocked when we're inside target_wait, so that should we actually | |
123 | want to wait for some more events, SIGCHLD handler does not steal them from | |
124 | us. Technically, it would be possible to add new events to the local queue but | |
125 | it's about the same amount of work as blocking SIGCHLD. | |
126 | ||
127 | This moving of events from pipe into local queue and back into pipe when we | |
128 | enter/leave linux-nat.c is somewhat ugly. Unfortunately, GDB event loop is | |
129 | home-grown and incapable to wait on any queue. | |
130 | ||
131 | Use of signals | |
132 | ============== | |
133 | ||
134 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
135 | signal is not entirely significant; we just need for a signal to be delivered, | |
136 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
137 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
138 | be queued once; we do not keep track of other sources of SIGSTOP. | |
139 | ||
140 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
141 | use them, because they have special behavior when the signal is generated - | |
142 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
143 | kills the entire thread group. | |
144 | ||
145 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
146 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
147 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
148 | ||
149 | We could use a real-time signal instead. This would solve those problems; we | |
150 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
151 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
152 | generates it, and there are races with trying to find a signal that is not | |
153 | blocked. */ | |
a0ef4274 | 154 | |
dba24537 AC |
155 | #ifndef O_LARGEFILE |
156 | #define O_LARGEFILE 0 | |
157 | #endif | |
0274a8ce | 158 | |
3993f6b1 DJ |
159 | /* If the system headers did not provide the constants, hard-code the normal |
160 | values. */ | |
161 | #ifndef PTRACE_EVENT_FORK | |
162 | ||
163 | #define PTRACE_SETOPTIONS 0x4200 | |
164 | #define PTRACE_GETEVENTMSG 0x4201 | |
165 | ||
166 | /* options set using PTRACE_SETOPTIONS */ | |
167 | #define PTRACE_O_TRACESYSGOOD 0x00000001 | |
168 | #define PTRACE_O_TRACEFORK 0x00000002 | |
169 | #define PTRACE_O_TRACEVFORK 0x00000004 | |
170 | #define PTRACE_O_TRACECLONE 0x00000008 | |
171 | #define PTRACE_O_TRACEEXEC 0x00000010 | |
9016a515 DJ |
172 | #define PTRACE_O_TRACEVFORKDONE 0x00000020 |
173 | #define PTRACE_O_TRACEEXIT 0x00000040 | |
3993f6b1 DJ |
174 | |
175 | /* Wait extended result codes for the above trace options. */ | |
176 | #define PTRACE_EVENT_FORK 1 | |
177 | #define PTRACE_EVENT_VFORK 2 | |
178 | #define PTRACE_EVENT_CLONE 3 | |
179 | #define PTRACE_EVENT_EXEC 4 | |
c874c7fc | 180 | #define PTRACE_EVENT_VFORK_DONE 5 |
9016a515 | 181 | #define PTRACE_EVENT_EXIT 6 |
3993f6b1 DJ |
182 | |
183 | #endif /* PTRACE_EVENT_FORK */ | |
184 | ||
185 | /* We can't always assume that this flag is available, but all systems | |
186 | with the ptrace event handlers also have __WALL, so it's safe to use | |
187 | here. */ | |
188 | #ifndef __WALL | |
189 | #define __WALL 0x40000000 /* Wait for any child. */ | |
190 | #endif | |
191 | ||
02d3ff8c UW |
192 | #ifndef PTRACE_GETSIGINFO |
193 | #define PTRACE_GETSIGINFO 0x4202 | |
194 | #endif | |
195 | ||
10d6c8cd DJ |
196 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
197 | the use of the multi-threaded target. */ | |
198 | static struct target_ops *linux_ops; | |
f973ed9c | 199 | static struct target_ops linux_ops_saved; |
10d6c8cd | 200 | |
9f0bdab8 DJ |
201 | /* The method to call, if any, when a new thread is attached. */ |
202 | static void (*linux_nat_new_thread) (ptid_t); | |
203 | ||
ac264b3b MS |
204 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
205 | Called by our to_xfer_partial. */ | |
206 | static LONGEST (*super_xfer_partial) (struct target_ops *, | |
207 | enum target_object, | |
208 | const char *, gdb_byte *, | |
209 | const gdb_byte *, | |
10d6c8cd DJ |
210 | ULONGEST, LONGEST); |
211 | ||
d6b0e80f | 212 | static int debug_linux_nat; |
920d2a44 AC |
213 | static void |
214 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
215 | struct cmd_list_element *c, const char *value) | |
216 | { | |
217 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
218 | value); | |
219 | } | |
d6b0e80f | 220 | |
b84876c2 PA |
221 | static int debug_linux_nat_async = 0; |
222 | static void | |
223 | show_debug_linux_nat_async (struct ui_file *file, int from_tty, | |
224 | struct cmd_list_element *c, const char *value) | |
225 | { | |
226 | fprintf_filtered (file, _("Debugging of GNU/Linux async lwp module is %s.\n"), | |
227 | value); | |
228 | } | |
229 | ||
10568435 JK |
230 | static int disable_randomization = 1; |
231 | ||
232 | static void | |
233 | show_disable_randomization (struct ui_file *file, int from_tty, | |
234 | struct cmd_list_element *c, const char *value) | |
235 | { | |
236 | #ifdef HAVE_PERSONALITY | |
237 | fprintf_filtered (file, _("\ | |
238 | Disabling randomization of debuggee's virtual address space is %s.\n"), | |
239 | value); | |
240 | #else /* !HAVE_PERSONALITY */ | |
241 | fputs_filtered (_("\ | |
242 | Disabling randomization of debuggee's virtual address space is unsupported on\n\ | |
243 | this platform.\n"), file); | |
244 | #endif /* !HAVE_PERSONALITY */ | |
245 | } | |
246 | ||
247 | static void | |
248 | set_disable_randomization (char *args, int from_tty, struct cmd_list_element *c) | |
249 | { | |
250 | #ifndef HAVE_PERSONALITY | |
251 | error (_("\ | |
252 | Disabling randomization of debuggee's virtual address space is unsupported on\n\ | |
253 | this platform.")); | |
254 | #endif /* !HAVE_PERSONALITY */ | |
255 | } | |
256 | ||
9016a515 DJ |
257 | static int linux_parent_pid; |
258 | ||
ae087d01 DJ |
259 | struct simple_pid_list |
260 | { | |
261 | int pid; | |
3d799a95 | 262 | int status; |
ae087d01 DJ |
263 | struct simple_pid_list *next; |
264 | }; | |
265 | struct simple_pid_list *stopped_pids; | |
266 | ||
3993f6b1 DJ |
267 | /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK |
268 | can not be used, 1 if it can. */ | |
269 | ||
270 | static int linux_supports_tracefork_flag = -1; | |
271 | ||
9016a515 DJ |
272 | /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have |
273 | PTRACE_O_TRACEVFORKDONE. */ | |
274 | ||
275 | static int linux_supports_tracevforkdone_flag = -1; | |
276 | ||
b84876c2 PA |
277 | /* Async mode support */ |
278 | ||
b84876c2 PA |
279 | /* True if async mode is currently on. */ |
280 | static int linux_nat_async_enabled; | |
281 | ||
282 | /* Zero if the async mode, although enabled, is masked, which means | |
283 | linux_nat_wait should behave as if async mode was off. */ | |
284 | static int linux_nat_async_mask_value = 1; | |
285 | ||
286 | /* The read/write ends of the pipe registered as waitable file in the | |
287 | event loop. */ | |
288 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
289 | ||
290 | /* Number of queued events in the pipe. */ | |
291 | static volatile int linux_nat_num_queued_events; | |
292 | ||
84e46146 | 293 | /* The possible SIGCHLD handling states. */ |
b84876c2 | 294 | |
84e46146 PA |
295 | enum sigchld_state |
296 | { | |
297 | /* SIGCHLD disabled, with action set to sigchld_handler, for the | |
298 | sigsuspend in linux_nat_wait. */ | |
299 | sigchld_sync, | |
300 | /* SIGCHLD enabled, with action set to async_sigchld_handler. */ | |
301 | sigchld_async, | |
302 | /* Set SIGCHLD to default action. Used while creating an | |
303 | inferior. */ | |
304 | sigchld_default | |
305 | }; | |
306 | ||
307 | /* The current SIGCHLD handling state. */ | |
308 | static enum sigchld_state linux_nat_async_events_state; | |
309 | ||
310 | static enum sigchld_state linux_nat_async_events (enum sigchld_state enable); | |
b84876c2 PA |
311 | static void pipe_to_local_event_queue (void); |
312 | static void local_event_queue_to_pipe (void); | |
313 | static void linux_nat_event_pipe_push (int pid, int status, int options); | |
314 | static int linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options); | |
315 | static void linux_nat_set_async_mode (int on); | |
316 | static void linux_nat_async (void (*callback) | |
317 | (enum inferior_event_type event_type, void *context), | |
318 | void *context); | |
319 | static int linux_nat_async_mask (int mask); | |
a0ef4274 | 320 | static int kill_lwp (int lwpid, int signo); |
b84876c2 | 321 | |
4c28f408 PA |
322 | static int send_sigint_callback (struct lwp_info *lp, void *data); |
323 | static int stop_callback (struct lwp_info *lp, void *data); | |
324 | ||
b84876c2 PA |
325 | /* Captures the result of a successful waitpid call, along with the |
326 | options used in that call. */ | |
327 | struct waitpid_result | |
328 | { | |
329 | int pid; | |
330 | int status; | |
331 | int options; | |
332 | struct waitpid_result *next; | |
333 | }; | |
334 | ||
335 | /* A singly-linked list of the results of the waitpid calls performed | |
336 | in the async SIGCHLD handler. */ | |
337 | static struct waitpid_result *waitpid_queue = NULL; | |
338 | ||
339 | static int | |
340 | queued_waitpid (int pid, int *status, int flags) | |
341 | { | |
342 | struct waitpid_result *msg = waitpid_queue, *prev = NULL; | |
343 | ||
344 | if (debug_linux_nat_async) | |
345 | fprintf_unfiltered (gdb_stdlog, | |
346 | "\ | |
84e46146 PA |
347 | QWPID: linux_nat_async_events_state(%d), linux_nat_num_queued_events(%d)\n", |
348 | linux_nat_async_events_state, | |
b84876c2 PA |
349 | linux_nat_num_queued_events); |
350 | ||
351 | if (flags & __WALL) | |
352 | { | |
353 | for (; msg; prev = msg, msg = msg->next) | |
354 | if (pid == -1 || pid == msg->pid) | |
355 | break; | |
356 | } | |
357 | else if (flags & __WCLONE) | |
358 | { | |
359 | for (; msg; prev = msg, msg = msg->next) | |
360 | if (msg->options & __WCLONE | |
361 | && (pid == -1 || pid == msg->pid)) | |
362 | break; | |
363 | } | |
364 | else | |
365 | { | |
366 | for (; msg; prev = msg, msg = msg->next) | |
367 | if ((msg->options & __WCLONE) == 0 | |
368 | && (pid == -1 || pid == msg->pid)) | |
369 | break; | |
370 | } | |
371 | ||
372 | if (msg) | |
373 | { | |
374 | int pid; | |
375 | ||
376 | if (prev) | |
377 | prev->next = msg->next; | |
378 | else | |
379 | waitpid_queue = msg->next; | |
380 | ||
381 | msg->next = NULL; | |
382 | if (status) | |
383 | *status = msg->status; | |
384 | pid = msg->pid; | |
385 | ||
386 | if (debug_linux_nat_async) | |
387 | fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n", | |
388 | pid, msg->status); | |
389 | xfree (msg); | |
390 | ||
391 | return pid; | |
392 | } | |
393 | ||
394 | if (debug_linux_nat_async) | |
395 | fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n"); | |
396 | ||
397 | if (status) | |
398 | *status = 0; | |
399 | return -1; | |
400 | } | |
401 | ||
402 | static void | |
403 | push_waitpid (int pid, int status, int options) | |
404 | { | |
405 | struct waitpid_result *event, *new_event; | |
406 | ||
407 | new_event = xmalloc (sizeof (*new_event)); | |
408 | new_event->pid = pid; | |
409 | new_event->status = status; | |
410 | new_event->options = options; | |
411 | new_event->next = NULL; | |
412 | ||
413 | if (waitpid_queue) | |
414 | { | |
415 | for (event = waitpid_queue; | |
416 | event && event->next; | |
417 | event = event->next) | |
418 | ; | |
419 | ||
420 | event->next = new_event; | |
421 | } | |
422 | else | |
423 | waitpid_queue = new_event; | |
424 | } | |
425 | ||
710151dd | 426 | /* Drain all queued events of PID. If PID is -1, the effect is of |
b84876c2 PA |
427 | draining all events. */ |
428 | static void | |
429 | drain_queued_events (int pid) | |
430 | { | |
431 | while (queued_waitpid (pid, NULL, __WALL) != -1) | |
432 | ; | |
433 | } | |
434 | ||
ae087d01 DJ |
435 | \f |
436 | /* Trivial list manipulation functions to keep track of a list of | |
437 | new stopped processes. */ | |
438 | static void | |
3d799a95 | 439 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
440 | { |
441 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
442 | new_pid->pid = pid; | |
3d799a95 | 443 | new_pid->status = status; |
ae087d01 DJ |
444 | new_pid->next = *listp; |
445 | *listp = new_pid; | |
446 | } | |
447 | ||
448 | static int | |
3d799a95 | 449 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *status) |
ae087d01 DJ |
450 | { |
451 | struct simple_pid_list **p; | |
452 | ||
453 | for (p = listp; *p != NULL; p = &(*p)->next) | |
454 | if ((*p)->pid == pid) | |
455 | { | |
456 | struct simple_pid_list *next = (*p)->next; | |
3d799a95 | 457 | *status = (*p)->status; |
ae087d01 DJ |
458 | xfree (*p); |
459 | *p = next; | |
460 | return 1; | |
461 | } | |
462 | return 0; | |
463 | } | |
464 | ||
3d799a95 DJ |
465 | static void |
466 | linux_record_stopped_pid (int pid, int status) | |
ae087d01 | 467 | { |
3d799a95 | 468 | add_to_pid_list (&stopped_pids, pid, status); |
ae087d01 DJ |
469 | } |
470 | ||
3993f6b1 DJ |
471 | \f |
472 | /* A helper function for linux_test_for_tracefork, called after fork (). */ | |
473 | ||
474 | static void | |
475 | linux_tracefork_child (void) | |
476 | { | |
477 | int ret; | |
478 | ||
479 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
480 | kill (getpid (), SIGSTOP); | |
481 | fork (); | |
48bb3cce | 482 | _exit (0); |
3993f6b1 DJ |
483 | } |
484 | ||
b84876c2 PA |
485 | /* Wrapper function for waitpid which handles EINTR, and checks for |
486 | locally queued events. */ | |
b957e937 DJ |
487 | |
488 | static int | |
489 | my_waitpid (int pid, int *status, int flags) | |
490 | { | |
491 | int ret; | |
b84876c2 PA |
492 | |
493 | /* There should be no concurrent calls to waitpid. */ | |
84e46146 | 494 | gdb_assert (linux_nat_async_events_state == sigchld_sync); |
b84876c2 PA |
495 | |
496 | ret = queued_waitpid (pid, status, flags); | |
497 | if (ret != -1) | |
498 | return ret; | |
499 | ||
b957e937 DJ |
500 | do |
501 | { | |
502 | ret = waitpid (pid, status, flags); | |
503 | } | |
504 | while (ret == -1 && errno == EINTR); | |
505 | ||
506 | return ret; | |
507 | } | |
508 | ||
509 | /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. | |
510 | ||
511 | First, we try to enable fork tracing on ORIGINAL_PID. If this fails, | |
512 | we know that the feature is not available. This may change the tracing | |
513 | options for ORIGINAL_PID, but we'll be setting them shortly anyway. | |
514 | ||
515 | However, if it succeeds, we don't know for sure that the feature is | |
516 | available; old versions of PTRACE_SETOPTIONS ignored unknown options. We | |
3993f6b1 | 517 | create a child process, attach to it, use PTRACE_SETOPTIONS to enable |
b957e937 DJ |
518 | fork tracing, and let it fork. If the process exits, we assume that we |
519 | can't use TRACEFORK; if we get the fork notification, and we can extract | |
520 | the new child's PID, then we assume that we can. */ | |
3993f6b1 DJ |
521 | |
522 | static void | |
b957e937 | 523 | linux_test_for_tracefork (int original_pid) |
3993f6b1 DJ |
524 | { |
525 | int child_pid, ret, status; | |
526 | long second_pid; | |
4c28f408 PA |
527 | enum sigchld_state async_events_original_state; |
528 | ||
529 | async_events_original_state = linux_nat_async_events (sigchld_sync); | |
3993f6b1 | 530 | |
b957e937 DJ |
531 | linux_supports_tracefork_flag = 0; |
532 | linux_supports_tracevforkdone_flag = 0; | |
533 | ||
534 | ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK); | |
535 | if (ret != 0) | |
536 | return; | |
537 | ||
3993f6b1 DJ |
538 | child_pid = fork (); |
539 | if (child_pid == -1) | |
e2e0b3e5 | 540 | perror_with_name (("fork")); |
3993f6b1 DJ |
541 | |
542 | if (child_pid == 0) | |
543 | linux_tracefork_child (); | |
544 | ||
b957e937 | 545 | ret = my_waitpid (child_pid, &status, 0); |
3993f6b1 | 546 | if (ret == -1) |
e2e0b3e5 | 547 | perror_with_name (("waitpid")); |
3993f6b1 | 548 | else if (ret != child_pid) |
8a3fe4f8 | 549 | error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret); |
3993f6b1 | 550 | if (! WIFSTOPPED (status)) |
8a3fe4f8 | 551 | error (_("linux_test_for_tracefork: waitpid: unexpected status %d."), status); |
3993f6b1 | 552 | |
3993f6b1 DJ |
553 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK); |
554 | if (ret != 0) | |
555 | { | |
b957e937 DJ |
556 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
557 | if (ret != 0) | |
558 | { | |
8a3fe4f8 | 559 | warning (_("linux_test_for_tracefork: failed to kill child")); |
4c28f408 | 560 | linux_nat_async_events (async_events_original_state); |
b957e937 DJ |
561 | return; |
562 | } | |
563 | ||
564 | ret = my_waitpid (child_pid, &status, 0); | |
565 | if (ret != child_pid) | |
8a3fe4f8 | 566 | warning (_("linux_test_for_tracefork: failed to wait for killed child")); |
b957e937 | 567 | else if (!WIFSIGNALED (status)) |
8a3fe4f8 AC |
568 | warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from " |
569 | "killed child"), status); | |
b957e937 | 570 | |
4c28f408 | 571 | linux_nat_async_events (async_events_original_state); |
3993f6b1 DJ |
572 | return; |
573 | } | |
574 | ||
9016a515 DJ |
575 | /* Check whether PTRACE_O_TRACEVFORKDONE is available. */ |
576 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, | |
577 | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE); | |
578 | linux_supports_tracevforkdone_flag = (ret == 0); | |
579 | ||
b957e937 DJ |
580 | ret = ptrace (PTRACE_CONT, child_pid, 0, 0); |
581 | if (ret != 0) | |
8a3fe4f8 | 582 | warning (_("linux_test_for_tracefork: failed to resume child")); |
b957e937 DJ |
583 | |
584 | ret = my_waitpid (child_pid, &status, 0); | |
585 | ||
3993f6b1 DJ |
586 | if (ret == child_pid && WIFSTOPPED (status) |
587 | && status >> 16 == PTRACE_EVENT_FORK) | |
588 | { | |
589 | second_pid = 0; | |
590 | ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid); | |
591 | if (ret == 0 && second_pid != 0) | |
592 | { | |
593 | int second_status; | |
594 | ||
595 | linux_supports_tracefork_flag = 1; | |
b957e937 DJ |
596 | my_waitpid (second_pid, &second_status, 0); |
597 | ret = ptrace (PTRACE_KILL, second_pid, 0, 0); | |
598 | if (ret != 0) | |
8a3fe4f8 | 599 | warning (_("linux_test_for_tracefork: failed to kill second child")); |
97725dc4 | 600 | my_waitpid (second_pid, &status, 0); |
3993f6b1 DJ |
601 | } |
602 | } | |
b957e937 | 603 | else |
8a3fe4f8 AC |
604 | warning (_("linux_test_for_tracefork: unexpected result from waitpid " |
605 | "(%d, status 0x%x)"), ret, status); | |
3993f6b1 | 606 | |
b957e937 DJ |
607 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
608 | if (ret != 0) | |
8a3fe4f8 | 609 | warning (_("linux_test_for_tracefork: failed to kill child")); |
b957e937 | 610 | my_waitpid (child_pid, &status, 0); |
4c28f408 PA |
611 | |
612 | linux_nat_async_events (async_events_original_state); | |
3993f6b1 DJ |
613 | } |
614 | ||
615 | /* Return non-zero iff we have tracefork functionality available. | |
616 | This function also sets linux_supports_tracefork_flag. */ | |
617 | ||
618 | static int | |
b957e937 | 619 | linux_supports_tracefork (int pid) |
3993f6b1 DJ |
620 | { |
621 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 622 | linux_test_for_tracefork (pid); |
3993f6b1 DJ |
623 | return linux_supports_tracefork_flag; |
624 | } | |
625 | ||
9016a515 | 626 | static int |
b957e937 | 627 | linux_supports_tracevforkdone (int pid) |
9016a515 DJ |
628 | { |
629 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 630 | linux_test_for_tracefork (pid); |
9016a515 DJ |
631 | return linux_supports_tracevforkdone_flag; |
632 | } | |
633 | ||
3993f6b1 | 634 | \f |
4de4c07c DJ |
635 | void |
636 | linux_enable_event_reporting (ptid_t ptid) | |
637 | { | |
d3587048 | 638 | int pid = ptid_get_lwp (ptid); |
4de4c07c DJ |
639 | int options; |
640 | ||
d3587048 DJ |
641 | if (pid == 0) |
642 | pid = ptid_get_pid (ptid); | |
643 | ||
b957e937 | 644 | if (! linux_supports_tracefork (pid)) |
4de4c07c DJ |
645 | return; |
646 | ||
a2f23071 DJ |
647 | options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC |
648 | | PTRACE_O_TRACECLONE; | |
b957e937 | 649 | if (linux_supports_tracevforkdone (pid)) |
9016a515 DJ |
650 | options |= PTRACE_O_TRACEVFORKDONE; |
651 | ||
652 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support | |
653 | read-only process state. */ | |
4de4c07c DJ |
654 | |
655 | ptrace (PTRACE_SETOPTIONS, pid, 0, options); | |
656 | } | |
657 | ||
6d8fd2b7 UW |
658 | static void |
659 | linux_child_post_attach (int pid) | |
4de4c07c DJ |
660 | { |
661 | linux_enable_event_reporting (pid_to_ptid (pid)); | |
0ec9a092 | 662 | check_for_thread_db (); |
4de4c07c DJ |
663 | } |
664 | ||
10d6c8cd | 665 | static void |
4de4c07c DJ |
666 | linux_child_post_startup_inferior (ptid_t ptid) |
667 | { | |
668 | linux_enable_event_reporting (ptid); | |
0ec9a092 | 669 | check_for_thread_db (); |
4de4c07c DJ |
670 | } |
671 | ||
6d8fd2b7 UW |
672 | static int |
673 | linux_child_follow_fork (struct target_ops *ops, int follow_child) | |
3993f6b1 | 674 | { |
4de4c07c DJ |
675 | ptid_t last_ptid; |
676 | struct target_waitstatus last_status; | |
9016a515 | 677 | int has_vforked; |
4de4c07c DJ |
678 | int parent_pid, child_pid; |
679 | ||
b84876c2 PA |
680 | if (target_can_async_p ()) |
681 | target_async (NULL, 0); | |
682 | ||
4de4c07c | 683 | get_last_target_status (&last_ptid, &last_status); |
9016a515 | 684 | has_vforked = (last_status.kind == TARGET_WAITKIND_VFORKED); |
d3587048 DJ |
685 | parent_pid = ptid_get_lwp (last_ptid); |
686 | if (parent_pid == 0) | |
687 | parent_pid = ptid_get_pid (last_ptid); | |
3a3e9ee3 | 688 | child_pid = PIDGET (last_status.value.related_pid); |
4de4c07c DJ |
689 | |
690 | if (! follow_child) | |
691 | { | |
692 | /* We're already attached to the parent, by default. */ | |
693 | ||
694 | /* Before detaching from the child, remove all breakpoints from | |
695 | it. (This won't actually modify the breakpoint list, but will | |
696 | physically remove the breakpoints from the child.) */ | |
9016a515 DJ |
697 | /* If we vforked this will remove the breakpoints from the parent |
698 | also, but they'll be reinserted below. */ | |
4de4c07c DJ |
699 | detach_breakpoints (child_pid); |
700 | ||
ac264b3b MS |
701 | /* Detach new forked process? */ |
702 | if (detach_fork) | |
f75c00e4 | 703 | { |
e85a822c | 704 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
705 | { |
706 | target_terminal_ours (); | |
707 | fprintf_filtered (gdb_stdlog, | |
708 | "Detaching after fork from child process %d.\n", | |
709 | child_pid); | |
710 | } | |
4de4c07c | 711 | |
ac264b3b MS |
712 | ptrace (PTRACE_DETACH, child_pid, 0, 0); |
713 | } | |
714 | else | |
715 | { | |
716 | struct fork_info *fp; | |
717 | /* Retain child fork in ptrace (stopped) state. */ | |
718 | fp = find_fork_pid (child_pid); | |
719 | if (!fp) | |
720 | fp = add_fork (child_pid); | |
721 | fork_save_infrun_state (fp, 0); | |
722 | } | |
9016a515 DJ |
723 | |
724 | if (has_vforked) | |
725 | { | |
b957e937 DJ |
726 | gdb_assert (linux_supports_tracefork_flag >= 0); |
727 | if (linux_supports_tracevforkdone (0)) | |
9016a515 DJ |
728 | { |
729 | int status; | |
730 | ||
731 | ptrace (PTRACE_CONT, parent_pid, 0, 0); | |
58aecb61 | 732 | my_waitpid (parent_pid, &status, __WALL); |
c874c7fc | 733 | if ((status >> 16) != PTRACE_EVENT_VFORK_DONE) |
8a3fe4f8 AC |
734 | warning (_("Unexpected waitpid result %06x when waiting for " |
735 | "vfork-done"), status); | |
9016a515 DJ |
736 | } |
737 | else | |
738 | { | |
739 | /* We can't insert breakpoints until the child has | |
740 | finished with the shared memory region. We need to | |
741 | wait until that happens. Ideal would be to just | |
742 | call: | |
743 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
744 | - waitpid (parent_pid, &status, __WALL); | |
745 | However, most architectures can't handle a syscall | |
746 | being traced on the way out if it wasn't traced on | |
747 | the way in. | |
748 | ||
749 | We might also think to loop, continuing the child | |
750 | until it exits or gets a SIGTRAP. One problem is | |
751 | that the child might call ptrace with PTRACE_TRACEME. | |
752 | ||
753 | There's no simple and reliable way to figure out when | |
754 | the vforked child will be done with its copy of the | |
755 | shared memory. We could step it out of the syscall, | |
756 | two instructions, let it go, and then single-step the | |
757 | parent once. When we have hardware single-step, this | |
758 | would work; with software single-step it could still | |
759 | be made to work but we'd have to be able to insert | |
760 | single-step breakpoints in the child, and we'd have | |
761 | to insert -just- the single-step breakpoint in the | |
762 | parent. Very awkward. | |
763 | ||
764 | In the end, the best we can do is to make sure it | |
765 | runs for a little while. Hopefully it will be out of | |
766 | range of any breakpoints we reinsert. Usually this | |
767 | is only the single-step breakpoint at vfork's return | |
768 | point. */ | |
769 | ||
770 | usleep (10000); | |
771 | } | |
772 | ||
773 | /* Since we vforked, breakpoints were removed in the parent | |
774 | too. Put them back. */ | |
775 | reattach_breakpoints (parent_pid); | |
776 | } | |
4de4c07c | 777 | } |
3993f6b1 | 778 | else |
4de4c07c DJ |
779 | { |
780 | char child_pid_spelling[40]; | |
781 | ||
782 | /* Needed to keep the breakpoint lists in sync. */ | |
9016a515 DJ |
783 | if (! has_vforked) |
784 | detach_breakpoints (child_pid); | |
4de4c07c DJ |
785 | |
786 | /* Before detaching from the parent, remove all breakpoints from it. */ | |
787 | remove_breakpoints (); | |
788 | ||
e85a822c | 789 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
790 | { |
791 | target_terminal_ours (); | |
ac264b3b MS |
792 | fprintf_filtered (gdb_stdlog, |
793 | "Attaching after fork to child process %d.\n", | |
794 | child_pid); | |
f75c00e4 | 795 | } |
4de4c07c | 796 | |
9016a515 DJ |
797 | /* If we're vforking, we may want to hold on to the parent until |
798 | the child exits or execs. At exec time we can remove the old | |
799 | breakpoints from the parent and detach it; at exit time we | |
800 | could do the same (or even, sneakily, resume debugging it - the | |
801 | child's exec has failed, or something similar). | |
802 | ||
803 | This doesn't clean up "properly", because we can't call | |
804 | target_detach, but that's OK; if the current target is "child", | |
805 | then it doesn't need any further cleanups, and lin_lwp will | |
806 | generally not encounter vfork (vfork is defined to fork | |
807 | in libpthread.so). | |
808 | ||
809 | The holding part is very easy if we have VFORKDONE events; | |
810 | but keeping track of both processes is beyond GDB at the | |
811 | moment. So we don't expose the parent to the rest of GDB. | |
812 | Instead we quietly hold onto it until such time as we can | |
813 | safely resume it. */ | |
814 | ||
815 | if (has_vforked) | |
816 | linux_parent_pid = parent_pid; | |
ac264b3b MS |
817 | else if (!detach_fork) |
818 | { | |
819 | struct fork_info *fp; | |
820 | /* Retain parent fork in ptrace (stopped) state. */ | |
821 | fp = find_fork_pid (parent_pid); | |
822 | if (!fp) | |
823 | fp = add_fork (parent_pid); | |
824 | fork_save_infrun_state (fp, 0); | |
825 | } | |
9016a515 | 826 | else |
b84876c2 | 827 | target_detach (NULL, 0); |
4de4c07c | 828 | |
9f0bdab8 | 829 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
ee057212 DJ |
830 | |
831 | /* Reinstall ourselves, since we might have been removed in | |
832 | target_detach (which does other necessary cleanup). */ | |
ac264b3b | 833 | |
ee057212 | 834 | push_target (ops); |
9f0bdab8 | 835 | linux_nat_switch_fork (inferior_ptid); |
ef29ce1a | 836 | check_for_thread_db (); |
4de4c07c DJ |
837 | |
838 | /* Reset breakpoints in the child as appropriate. */ | |
839 | follow_inferior_reset_breakpoints (); | |
840 | } | |
841 | ||
b84876c2 PA |
842 | if (target_can_async_p ()) |
843 | target_async (inferior_event_handler, 0); | |
844 | ||
4de4c07c DJ |
845 | return 0; |
846 | } | |
847 | ||
4de4c07c | 848 | \f |
6d8fd2b7 UW |
849 | static void |
850 | linux_child_insert_fork_catchpoint (int pid) | |
4de4c07c | 851 | { |
b957e937 | 852 | if (! linux_supports_tracefork (pid)) |
8a3fe4f8 | 853 | error (_("Your system does not support fork catchpoints.")); |
3993f6b1 DJ |
854 | } |
855 | ||
6d8fd2b7 UW |
856 | static void |
857 | linux_child_insert_vfork_catchpoint (int pid) | |
3993f6b1 | 858 | { |
b957e937 | 859 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 860 | error (_("Your system does not support vfork catchpoints.")); |
3993f6b1 DJ |
861 | } |
862 | ||
6d8fd2b7 UW |
863 | static void |
864 | linux_child_insert_exec_catchpoint (int pid) | |
3993f6b1 | 865 | { |
b957e937 | 866 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 867 | error (_("Your system does not support exec catchpoints.")); |
3993f6b1 DJ |
868 | } |
869 | ||
d6b0e80f AC |
870 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
871 | are processes sharing the same VM space. A multi-threaded process | |
872 | is basically a group of such processes. However, such a grouping | |
873 | is almost entirely a user-space issue; the kernel doesn't enforce | |
874 | such a grouping at all (this might change in the future). In | |
875 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
876 | Threads library) to provide such a grouping. | |
877 | ||
878 | It is perfectly well possible to write a multi-threaded application | |
879 | without the assistance of a threads library, by using the clone | |
880 | system call directly. This module should be able to give some | |
881 | rudimentary support for debugging such applications if developers | |
882 | specify the CLONE_PTRACE flag in the clone system call, and are | |
883 | using the Linux kernel 2.4 or above. | |
884 | ||
885 | Note that there are some peculiarities in GNU/Linux that affect | |
886 | this code: | |
887 | ||
888 | - In general one should specify the __WCLONE flag to waitpid in | |
889 | order to make it report events for any of the cloned processes | |
890 | (and leave it out for the initial process). However, if a cloned | |
891 | process has exited the exit status is only reported if the | |
892 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
893 | we cannot use it since GDB must work on older systems too. | |
894 | ||
895 | - When a traced, cloned process exits and is waited for by the | |
896 | debugger, the kernel reassigns it to the original parent and | |
897 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
898 | library doesn't notice this, which leads to the "zombie problem": | |
899 | When debugged a multi-threaded process that spawns a lot of | |
900 | threads will run out of processes, even if the threads exit, | |
901 | because the "zombies" stay around. */ | |
902 | ||
903 | /* List of known LWPs. */ | |
9f0bdab8 | 904 | struct lwp_info *lwp_list; |
d6b0e80f AC |
905 | |
906 | /* Number of LWPs in the list. */ | |
907 | static int num_lwps; | |
d6b0e80f AC |
908 | \f |
909 | ||
d6b0e80f AC |
910 | /* Original signal mask. */ |
911 | static sigset_t normal_mask; | |
912 | ||
913 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
914 | _initialize_linux_nat. */ | |
915 | static sigset_t suspend_mask; | |
916 | ||
b84876c2 PA |
917 | /* SIGCHLD action for synchronous mode. */ |
918 | struct sigaction sync_sigchld_action; | |
919 | ||
920 | /* SIGCHLD action for asynchronous mode. */ | |
921 | static struct sigaction async_sigchld_action; | |
84e46146 PA |
922 | |
923 | /* SIGCHLD default action, to pass to new inferiors. */ | |
924 | static struct sigaction sigchld_default_action; | |
d6b0e80f AC |
925 | \f |
926 | ||
927 | /* Prototypes for local functions. */ | |
928 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
929 | static int linux_nat_thread_alive (ptid_t ptid); | |
6d8fd2b7 | 930 | static char *linux_child_pid_to_exec_file (int pid); |
710151dd PA |
931 | static int cancel_breakpoint (struct lwp_info *lp); |
932 | ||
d6b0e80f AC |
933 | \f |
934 | /* Convert wait status STATUS to a string. Used for printing debug | |
935 | messages only. */ | |
936 | ||
937 | static char * | |
938 | status_to_str (int status) | |
939 | { | |
940 | static char buf[64]; | |
941 | ||
942 | if (WIFSTOPPED (status)) | |
943 | snprintf (buf, sizeof (buf), "%s (stopped)", | |
944 | strsignal (WSTOPSIG (status))); | |
945 | else if (WIFSIGNALED (status)) | |
946 | snprintf (buf, sizeof (buf), "%s (terminated)", | |
947 | strsignal (WSTOPSIG (status))); | |
948 | else | |
949 | snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status)); | |
950 | ||
951 | return buf; | |
952 | } | |
953 | ||
954 | /* Initialize the list of LWPs. Note that this module, contrary to | |
955 | what GDB's generic threads layer does for its thread list, | |
956 | re-initializes the LWP lists whenever we mourn or detach (which | |
957 | doesn't involve mourning) the inferior. */ | |
958 | ||
959 | static void | |
960 | init_lwp_list (void) | |
961 | { | |
962 | struct lwp_info *lp, *lpnext; | |
963 | ||
964 | for (lp = lwp_list; lp; lp = lpnext) | |
965 | { | |
966 | lpnext = lp->next; | |
967 | xfree (lp); | |
968 | } | |
969 | ||
970 | lwp_list = NULL; | |
971 | num_lwps = 0; | |
d6b0e80f AC |
972 | } |
973 | ||
f973ed9c | 974 | /* Add the LWP specified by PID to the list. Return a pointer to the |
9f0bdab8 DJ |
975 | structure describing the new LWP. The LWP should already be stopped |
976 | (with an exception for the very first LWP). */ | |
d6b0e80f AC |
977 | |
978 | static struct lwp_info * | |
979 | add_lwp (ptid_t ptid) | |
980 | { | |
981 | struct lwp_info *lp; | |
982 | ||
983 | gdb_assert (is_lwp (ptid)); | |
984 | ||
985 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
986 | ||
987 | memset (lp, 0, sizeof (struct lwp_info)); | |
988 | ||
989 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
990 | ||
991 | lp->ptid = ptid; | |
992 | ||
993 | lp->next = lwp_list; | |
994 | lwp_list = lp; | |
f973ed9c | 995 | ++num_lwps; |
d6b0e80f | 996 | |
9f0bdab8 DJ |
997 | if (num_lwps > 1 && linux_nat_new_thread != NULL) |
998 | linux_nat_new_thread (ptid); | |
999 | ||
d6b0e80f AC |
1000 | return lp; |
1001 | } | |
1002 | ||
1003 | /* Remove the LWP specified by PID from the list. */ | |
1004 | ||
1005 | static void | |
1006 | delete_lwp (ptid_t ptid) | |
1007 | { | |
1008 | struct lwp_info *lp, *lpprev; | |
1009 | ||
1010 | lpprev = NULL; | |
1011 | ||
1012 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
1013 | if (ptid_equal (lp->ptid, ptid)) | |
1014 | break; | |
1015 | ||
1016 | if (!lp) | |
1017 | return; | |
1018 | ||
d6b0e80f AC |
1019 | num_lwps--; |
1020 | ||
1021 | if (lpprev) | |
1022 | lpprev->next = lp->next; | |
1023 | else | |
1024 | lwp_list = lp->next; | |
1025 | ||
1026 | xfree (lp); | |
1027 | } | |
1028 | ||
1029 | /* Return a pointer to the structure describing the LWP corresponding | |
1030 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1031 | ||
1032 | static struct lwp_info * | |
1033 | find_lwp_pid (ptid_t ptid) | |
1034 | { | |
1035 | struct lwp_info *lp; | |
1036 | int lwp; | |
1037 | ||
1038 | if (is_lwp (ptid)) | |
1039 | lwp = GET_LWP (ptid); | |
1040 | else | |
1041 | lwp = GET_PID (ptid); | |
1042 | ||
1043 | for (lp = lwp_list; lp; lp = lp->next) | |
1044 | if (lwp == GET_LWP (lp->ptid)) | |
1045 | return lp; | |
1046 | ||
1047 | return NULL; | |
1048 | } | |
1049 | ||
1050 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1051 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1052 | pointer to the structure describing that LWP immediately. | |
1053 | Otherwise return NULL. */ | |
1054 | ||
1055 | struct lwp_info * | |
1056 | iterate_over_lwps (int (*callback) (struct lwp_info *, void *), void *data) | |
1057 | { | |
1058 | struct lwp_info *lp, *lpnext; | |
1059 | ||
1060 | for (lp = lwp_list; lp; lp = lpnext) | |
1061 | { | |
1062 | lpnext = lp->next; | |
1063 | if ((*callback) (lp, data)) | |
1064 | return lp; | |
1065 | } | |
1066 | ||
1067 | return NULL; | |
1068 | } | |
1069 | ||
f973ed9c DJ |
1070 | /* Update our internal state when changing from one fork (checkpoint, |
1071 | et cetera) to another indicated by NEW_PTID. We can only switch | |
1072 | single-threaded applications, so we only create one new LWP, and | |
1073 | the previous list is discarded. */ | |
1074 | ||
1075 | void | |
1076 | linux_nat_switch_fork (ptid_t new_ptid) | |
1077 | { | |
1078 | struct lwp_info *lp; | |
1079 | ||
1080 | init_lwp_list (); | |
1081 | lp = add_lwp (new_ptid); | |
1082 | lp->stopped = 1; | |
e26af52f | 1083 | |
4f8d22e3 PA |
1084 | init_thread_list (); |
1085 | add_thread_silent (new_ptid); | |
e26af52f DJ |
1086 | } |
1087 | ||
e26af52f DJ |
1088 | /* Handle the exit of a single thread LP. */ |
1089 | ||
1090 | static void | |
1091 | exit_lwp (struct lwp_info *lp) | |
1092 | { | |
063bfe2e VP |
1093 | struct thread_info *th = find_thread_pid (lp->ptid); |
1094 | ||
1095 | if (th) | |
e26af52f | 1096 | { |
17faa917 DJ |
1097 | if (print_thread_events) |
1098 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1099 | ||
4f8d22e3 | 1100 | delete_thread (lp->ptid); |
e26af52f DJ |
1101 | } |
1102 | ||
1103 | delete_lwp (lp->ptid); | |
1104 | } | |
1105 | ||
a0ef4274 DJ |
1106 | /* Detect `T (stopped)' in `/proc/PID/status'. |
1107 | Other states including `T (tracing stop)' are reported as false. */ | |
1108 | ||
1109 | static int | |
1110 | pid_is_stopped (pid_t pid) | |
1111 | { | |
1112 | FILE *status_file; | |
1113 | char buf[100]; | |
1114 | int retval = 0; | |
1115 | ||
1116 | snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid); | |
1117 | status_file = fopen (buf, "r"); | |
1118 | if (status_file != NULL) | |
1119 | { | |
1120 | int have_state = 0; | |
1121 | ||
1122 | while (fgets (buf, sizeof (buf), status_file)) | |
1123 | { | |
1124 | if (strncmp (buf, "State:", 6) == 0) | |
1125 | { | |
1126 | have_state = 1; | |
1127 | break; | |
1128 | } | |
1129 | } | |
1130 | if (have_state && strstr (buf, "T (stopped)") != NULL) | |
1131 | retval = 1; | |
1132 | fclose (status_file); | |
1133 | } | |
1134 | return retval; | |
1135 | } | |
1136 | ||
1137 | /* Wait for the LWP specified by LP, which we have just attached to. | |
1138 | Returns a wait status for that LWP, to cache. */ | |
1139 | ||
1140 | static int | |
1141 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1142 | int *signalled) | |
1143 | { | |
1144 | pid_t new_pid, pid = GET_LWP (ptid); | |
1145 | int status; | |
1146 | ||
1147 | if (pid_is_stopped (pid)) | |
1148 | { | |
1149 | if (debug_linux_nat) | |
1150 | fprintf_unfiltered (gdb_stdlog, | |
1151 | "LNPAW: Attaching to a stopped process\n"); | |
1152 | ||
1153 | /* The process is definitely stopped. It is in a job control | |
1154 | stop, unless the kernel predates the TASK_STOPPED / | |
1155 | TASK_TRACED distinction, in which case it might be in a | |
1156 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1157 | can kill it, signal it, et cetera. | |
1158 | ||
1159 | First make sure there is a pending SIGSTOP. Since we are | |
1160 | already attached, the process can not transition from stopped | |
1161 | to running without a PTRACE_CONT; so we know this signal will | |
1162 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1163 | probably already in the queue (unless this kernel is old | |
1164 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1165 | is not an RT signal, it can only be queued once. */ | |
1166 | kill_lwp (pid, SIGSTOP); | |
1167 | ||
1168 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1169 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1170 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1171 | } | |
1172 | ||
1173 | /* Make sure the initial process is stopped. The user-level threads | |
1174 | layer might want to poke around in the inferior, and that won't | |
1175 | work if things haven't stabilized yet. */ | |
1176 | new_pid = my_waitpid (pid, &status, 0); | |
1177 | if (new_pid == -1 && errno == ECHILD) | |
1178 | { | |
1179 | if (first) | |
1180 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1181 | ||
1182 | /* Try again with __WCLONE to check cloned processes. */ | |
1183 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1184 | *cloned = 1; | |
1185 | } | |
1186 | ||
1187 | gdb_assert (pid == new_pid && WIFSTOPPED (status)); | |
1188 | ||
1189 | if (WSTOPSIG (status) != SIGSTOP) | |
1190 | { | |
1191 | *signalled = 1; | |
1192 | if (debug_linux_nat) | |
1193 | fprintf_unfiltered (gdb_stdlog, | |
1194 | "LNPAW: Received %s after attaching\n", | |
1195 | status_to_str (status)); | |
1196 | } | |
1197 | ||
1198 | return status; | |
1199 | } | |
1200 | ||
1201 | /* Attach to the LWP specified by PID. Return 0 if successful or -1 | |
1202 | if the new LWP could not be attached. */ | |
d6b0e80f | 1203 | |
9ee57c33 | 1204 | int |
93815fbf | 1205 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1206 | { |
9ee57c33 | 1207 | struct lwp_info *lp; |
84e46146 | 1208 | enum sigchld_state async_events_original_state; |
d6b0e80f AC |
1209 | |
1210 | gdb_assert (is_lwp (ptid)); | |
1211 | ||
84e46146 | 1212 | async_events_original_state = linux_nat_async_events (sigchld_sync); |
d6b0e80f | 1213 | |
9ee57c33 | 1214 | lp = find_lwp_pid (ptid); |
d6b0e80f AC |
1215 | |
1216 | /* We assume that we're already attached to any LWP that has an id | |
1217 | equal to the overall process id, and to any LWP that is already | |
1218 | in our list of LWPs. If we're not seeing exit events from threads | |
1219 | and we've had PID wraparound since we last tried to stop all threads, | |
1220 | this assumption might be wrong; fortunately, this is very unlikely | |
1221 | to happen. */ | |
9ee57c33 | 1222 | if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL) |
d6b0e80f | 1223 | { |
a0ef4274 | 1224 | int status, cloned = 0, signalled = 0; |
d6b0e80f AC |
1225 | |
1226 | if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0) | |
9ee57c33 DJ |
1227 | { |
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 DJ |
1243 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
1244 | lp = add_lwp (ptid); | |
1245 | lp->stopped = 1; | |
1246 | lp->cloned = cloned; | |
1247 | lp->signalled = signalled; | |
1248 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1249 | { |
a0ef4274 DJ |
1250 | lp->resumed = 1; |
1251 | lp->status = status; | |
d6b0e80f AC |
1252 | } |
1253 | ||
a0ef4274 | 1254 | target_post_attach (GET_LWP (lp->ptid)); |
d6b0e80f AC |
1255 | |
1256 | if (debug_linux_nat) | |
1257 | { | |
1258 | fprintf_unfiltered (gdb_stdlog, | |
1259 | "LLAL: waitpid %s received %s\n", | |
1260 | target_pid_to_str (ptid), | |
1261 | status_to_str (status)); | |
1262 | } | |
1263 | } | |
1264 | else | |
1265 | { | |
1266 | /* We assume that the LWP representing the original process is | |
1267 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1268 | that the GNU/linux ptrace layer uses to keep track of |
1269 | threads. Note that this won't have already been done since | |
1270 | the main thread will have, we assume, been stopped by an | |
1271 | attach from a different layer. */ | |
9ee57c33 DJ |
1272 | if (lp == NULL) |
1273 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1274 | lp->stopped = 1; |
1275 | } | |
9ee57c33 | 1276 | |
84e46146 | 1277 | linux_nat_async_events (async_events_original_state); |
9ee57c33 | 1278 | return 0; |
d6b0e80f AC |
1279 | } |
1280 | ||
b84876c2 PA |
1281 | static void |
1282 | linux_nat_create_inferior (char *exec_file, char *allargs, char **env, | |
1283 | int from_tty) | |
1284 | { | |
1285 | int saved_async = 0; | |
10568435 JK |
1286 | #ifdef HAVE_PERSONALITY |
1287 | int personality_orig = 0, personality_set = 0; | |
1288 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1289 | |
1290 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1291 | we have to mask the async mode. */ | |
1292 | ||
1293 | if (target_can_async_p ()) | |
84e46146 PA |
1294 | /* Mask async mode. Creating a child requires a loop calling |
1295 | wait_for_inferior currently. */ | |
b84876c2 PA |
1296 | saved_async = linux_nat_async_mask (0); |
1297 | else | |
1298 | { | |
1299 | /* Restore the original signal mask. */ | |
1300 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1301 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1302 | suspend_mask = normal_mask; | |
1303 | sigdelset (&suspend_mask, SIGCHLD); | |
1304 | } | |
1305 | ||
84e46146 PA |
1306 | /* Set SIGCHLD to the default action, until after execing the child, |
1307 | since the inferior inherits the superior's signal mask. It will | |
1308 | be blocked again in linux_nat_wait, which is only reached after | |
1309 | the inferior execing. */ | |
1310 | linux_nat_async_events (sigchld_default); | |
1311 | ||
10568435 JK |
1312 | #ifdef HAVE_PERSONALITY |
1313 | if (disable_randomization) | |
1314 | { | |
1315 | errno = 0; | |
1316 | personality_orig = personality (0xffffffff); | |
1317 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1318 | { | |
1319 | personality_set = 1; | |
1320 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1321 | } | |
1322 | if (errno != 0 || (personality_set | |
1323 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1324 | warning (_("Error disabling address space randomization: %s"), | |
1325 | safe_strerror (errno)); | |
1326 | } | |
1327 | #endif /* HAVE_PERSONALITY */ | |
1328 | ||
b84876c2 PA |
1329 | linux_ops->to_create_inferior (exec_file, allargs, env, from_tty); |
1330 | ||
10568435 JK |
1331 | #ifdef HAVE_PERSONALITY |
1332 | if (personality_set) | |
1333 | { | |
1334 | errno = 0; | |
1335 | personality (personality_orig); | |
1336 | if (errno != 0) | |
1337 | warning (_("Error restoring address space randomization: %s"), | |
1338 | safe_strerror (errno)); | |
1339 | } | |
1340 | #endif /* HAVE_PERSONALITY */ | |
1341 | ||
b84876c2 PA |
1342 | if (saved_async) |
1343 | linux_nat_async_mask (saved_async); | |
1344 | } | |
1345 | ||
d6b0e80f AC |
1346 | static void |
1347 | linux_nat_attach (char *args, int from_tty) | |
1348 | { | |
1349 | struct lwp_info *lp; | |
d6b0e80f AC |
1350 | int status; |
1351 | ||
1352 | /* FIXME: We should probably accept a list of process id's, and | |
1353 | attach all of them. */ | |
10d6c8cd | 1354 | linux_ops->to_attach (args, from_tty); |
d6b0e80f | 1355 | |
b84876c2 PA |
1356 | if (!target_can_async_p ()) |
1357 | { | |
1358 | /* Restore the original signal mask. */ | |
1359 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1360 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1361 | suspend_mask = normal_mask; | |
1362 | sigdelset (&suspend_mask, SIGCHLD); | |
1363 | } | |
1364 | ||
9f0bdab8 DJ |
1365 | /* Add the initial process as the first LWP to the list. */ |
1366 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid)); | |
1367 | lp = add_lwp (inferior_ptid); | |
a0ef4274 DJ |
1368 | |
1369 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1370 | &lp->signalled); | |
1371 | lp->stopped = 1; | |
9f0bdab8 | 1372 | |
403fe197 PA |
1373 | /* If this process is not using thread_db, then we still don't |
1374 | detect any other threads, but add at least this one. */ | |
1375 | add_thread_silent (lp->ptid); | |
1376 | ||
a0ef4274 | 1377 | /* Save the wait status to report later. */ |
d6b0e80f | 1378 | lp->resumed = 1; |
a0ef4274 DJ |
1379 | if (debug_linux_nat) |
1380 | fprintf_unfiltered (gdb_stdlog, | |
1381 | "LNA: waitpid %ld, saving status %s\n", | |
1382 | (long) GET_PID (lp->ptid), status_to_str (status)); | |
710151dd PA |
1383 | |
1384 | if (!target_can_async_p ()) | |
a0ef4274 | 1385 | lp->status = status; |
710151dd PA |
1386 | else |
1387 | { | |
1388 | /* We already waited for this LWP, so put the wait result on the | |
1389 | pipe. The event loop will wake up and gets us to handling | |
1390 | this event. */ | |
a0ef4274 DJ |
1391 | linux_nat_event_pipe_push (GET_PID (lp->ptid), status, |
1392 | lp->cloned ? __WCLONE : 0); | |
b84876c2 PA |
1393 | /* Register in the event loop. */ |
1394 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1395 | } |
1396 | } | |
1397 | ||
a0ef4274 DJ |
1398 | /* Get pending status of LP. */ |
1399 | static int | |
1400 | get_pending_status (struct lwp_info *lp, int *status) | |
1401 | { | |
1402 | struct target_waitstatus last; | |
1403 | ptid_t last_ptid; | |
1404 | ||
1405 | get_last_target_status (&last_ptid, &last); | |
1406 | ||
1407 | /* If this lwp is the ptid that GDB is processing an event from, the | |
1408 | signal will be in stop_signal. Otherwise, in all-stop + sync | |
1409 | mode, we may cache pending events in lp->status while trying to | |
1410 | stop all threads (see stop_wait_callback). In async mode, the | |
1411 | events are always cached in waitpid_queue. */ | |
1412 | ||
1413 | *status = 0; | |
4c28f408 PA |
1414 | |
1415 | if (non_stop) | |
a0ef4274 | 1416 | { |
4c28f408 PA |
1417 | enum target_signal signo = TARGET_SIGNAL_0; |
1418 | ||
1419 | if (is_executing (lp->ptid)) | |
1420 | { | |
1421 | /* If the core thought this lwp was executing --- e.g., the | |
1422 | executing property hasn't been updated yet, but the | |
1423 | thread has been stopped with a stop_callback / | |
1424 | stop_wait_callback sequence (see linux_nat_detach for | |
1425 | example) --- we can only have pending events in the local | |
1426 | queue. */ | |
1427 | if (queued_waitpid (GET_LWP (lp->ptid), status, __WALL) != -1) | |
1428 | { | |
1429 | if (WIFSTOPPED (status)) | |
1430 | signo = target_signal_from_host (WSTOPSIG (status)); | |
1431 | ||
1432 | /* If not stopped, then the lwp is gone, no use in | |
1433 | resending a signal. */ | |
1434 | } | |
1435 | } | |
1436 | else | |
1437 | { | |
1438 | /* If the core knows the thread is not executing, then we | |
1439 | have the last signal recorded in | |
1440 | thread_info->stop_signal, unless this is inferior_ptid, | |
1441 | in which case, it's in the global stop_signal, due to | |
1442 | context switching. */ | |
1443 | ||
1444 | if (ptid_equal (lp->ptid, inferior_ptid)) | |
1445 | signo = stop_signal; | |
1446 | else | |
1447 | { | |
1448 | struct thread_info *tp = find_thread_pid (lp->ptid); | |
1449 | gdb_assert (tp); | |
1450 | signo = tp->stop_signal; | |
1451 | } | |
1452 | } | |
1453 | ||
1454 | if (signo != TARGET_SIGNAL_0 | |
1455 | && !signal_pass_state (signo)) | |
1456 | { | |
1457 | if (debug_linux_nat) | |
1458 | fprintf_unfiltered (gdb_stdlog, "\ | |
1459 | GPT: lwp %s had signal %s, but it is in no pass state\n", | |
1460 | target_pid_to_str (lp->ptid), | |
1461 | target_signal_to_string (signo)); | |
1462 | } | |
1463 | else | |
1464 | { | |
1465 | if (signo != TARGET_SIGNAL_0) | |
1466 | *status = W_STOPCODE (target_signal_to_host (signo)); | |
1467 | ||
1468 | if (debug_linux_nat) | |
1469 | fprintf_unfiltered (gdb_stdlog, | |
1470 | "GPT: lwp %s as pending signal %s\n", | |
1471 | target_pid_to_str (lp->ptid), | |
1472 | target_signal_to_string (signo)); | |
1473 | } | |
a0ef4274 | 1474 | } |
a0ef4274 | 1475 | else |
4c28f408 PA |
1476 | { |
1477 | if (GET_LWP (lp->ptid) == GET_LWP (last_ptid)) | |
1478 | { | |
1479 | if (stop_signal != TARGET_SIGNAL_0 | |
1480 | && signal_pass_state (stop_signal)) | |
1481 | *status = W_STOPCODE (target_signal_to_host (stop_signal)); | |
1482 | } | |
1483 | else if (target_can_async_p ()) | |
1484 | queued_waitpid (GET_LWP (lp->ptid), status, __WALL); | |
1485 | else | |
1486 | *status = lp->status; | |
1487 | } | |
a0ef4274 DJ |
1488 | |
1489 | return 0; | |
1490 | } | |
1491 | ||
d6b0e80f AC |
1492 | static int |
1493 | detach_callback (struct lwp_info *lp, void *data) | |
1494 | { | |
1495 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1496 | ||
1497 | if (debug_linux_nat && lp->status) | |
1498 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1499 | strsignal (WSTOPSIG (lp->status)), | |
1500 | target_pid_to_str (lp->ptid)); | |
1501 | ||
a0ef4274 DJ |
1502 | /* If there is a pending SIGSTOP, get rid of it. */ |
1503 | if (lp->signalled) | |
d6b0e80f | 1504 | { |
d6b0e80f AC |
1505 | if (debug_linux_nat) |
1506 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1507 | "DC: Sending SIGCONT to %s\n", |
1508 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1509 | |
a0ef4274 | 1510 | kill_lwp (GET_LWP (lp->ptid), SIGCONT); |
d6b0e80f | 1511 | lp->signalled = 0; |
d6b0e80f AC |
1512 | } |
1513 | ||
1514 | /* We don't actually detach from the LWP that has an id equal to the | |
1515 | overall process id just yet. */ | |
1516 | if (GET_LWP (lp->ptid) != GET_PID (lp->ptid)) | |
1517 | { | |
a0ef4274 DJ |
1518 | int status = 0; |
1519 | ||
1520 | /* Pass on any pending signal for this LWP. */ | |
1521 | get_pending_status (lp, &status); | |
1522 | ||
d6b0e80f AC |
1523 | errno = 0; |
1524 | if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0, | |
a0ef4274 | 1525 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1526 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1527 | safe_strerror (errno)); |
1528 | ||
1529 | if (debug_linux_nat) | |
1530 | fprintf_unfiltered (gdb_stdlog, | |
1531 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1532 | target_pid_to_str (lp->ptid), | |
1533 | strsignal (WSTOPSIG (lp->status))); | |
1534 | ||
1535 | delete_lwp (lp->ptid); | |
1536 | } | |
1537 | ||
1538 | return 0; | |
1539 | } | |
1540 | ||
1541 | static void | |
1542 | linux_nat_detach (char *args, int from_tty) | |
1543 | { | |
b84876c2 | 1544 | int pid; |
a0ef4274 DJ |
1545 | int status; |
1546 | enum target_signal sig; | |
1547 | ||
b84876c2 PA |
1548 | if (target_can_async_p ()) |
1549 | linux_nat_async (NULL, 0); | |
1550 | ||
4c28f408 PA |
1551 | /* Stop all threads before detaching. ptrace requires that the |
1552 | thread is stopped to sucessfully detach. */ | |
1553 | iterate_over_lwps (stop_callback, NULL); | |
1554 | /* ... and wait until all of them have reported back that | |
1555 | they're no longer running. */ | |
1556 | iterate_over_lwps (stop_wait_callback, NULL); | |
1557 | ||
d6b0e80f AC |
1558 | iterate_over_lwps (detach_callback, NULL); |
1559 | ||
1560 | /* Only the initial process should be left right now. */ | |
1561 | gdb_assert (num_lwps == 1); | |
1562 | ||
a0ef4274 DJ |
1563 | /* Pass on any pending signal for the last LWP. */ |
1564 | if ((args == NULL || *args == '\0') | |
1565 | && get_pending_status (lwp_list, &status) != -1 | |
1566 | && WIFSTOPPED (status)) | |
1567 | { | |
1568 | /* Put the signal number in ARGS so that inf_ptrace_detach will | |
1569 | pass it along with PTRACE_DETACH. */ | |
1570 | args = alloca (8); | |
1571 | sprintf (args, "%d", (int) WSTOPSIG (status)); | |
1572 | fprintf_unfiltered (gdb_stdlog, | |
1573 | "LND: Sending signal %s to %s\n", | |
1574 | args, | |
1575 | target_pid_to_str (lwp_list->ptid)); | |
1576 | } | |
1577 | ||
d6b0e80f AC |
1578 | /* Destroy LWP info; it's no longer valid. */ |
1579 | init_lwp_list (); | |
1580 | ||
b84876c2 PA |
1581 | pid = GET_PID (inferior_ptid); |
1582 | inferior_ptid = pid_to_ptid (pid); | |
10d6c8cd | 1583 | linux_ops->to_detach (args, from_tty); |
b84876c2 PA |
1584 | |
1585 | if (target_can_async_p ()) | |
1586 | drain_queued_events (pid); | |
d6b0e80f AC |
1587 | } |
1588 | ||
1589 | /* Resume LP. */ | |
1590 | ||
1591 | static int | |
1592 | resume_callback (struct lwp_info *lp, void *data) | |
1593 | { | |
1594 | if (lp->stopped && lp->status == 0) | |
1595 | { | |
10d6c8cd DJ |
1596 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
1597 | 0, TARGET_SIGNAL_0); | |
d6b0e80f AC |
1598 | if (debug_linux_nat) |
1599 | fprintf_unfiltered (gdb_stdlog, | |
1600 | "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n", | |
1601 | target_pid_to_str (lp->ptid)); | |
1602 | lp->stopped = 0; | |
1603 | lp->step = 0; | |
9f0bdab8 | 1604 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
d6b0e80f | 1605 | } |
57380f4e DJ |
1606 | else if (lp->stopped && debug_linux_nat) |
1607 | fprintf_unfiltered (gdb_stdlog, "RC: Not resuming sibling %s (has pending)\n", | |
1608 | target_pid_to_str (lp->ptid)); | |
1609 | else if (debug_linux_nat) | |
1610 | fprintf_unfiltered (gdb_stdlog, "RC: Not resuming sibling %s (not stopped)\n", | |
1611 | target_pid_to_str (lp->ptid)); | |
d6b0e80f AC |
1612 | |
1613 | return 0; | |
1614 | } | |
1615 | ||
1616 | static int | |
1617 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1618 | { | |
1619 | lp->resumed = 0; | |
1620 | return 0; | |
1621 | } | |
1622 | ||
1623 | static int | |
1624 | resume_set_callback (struct lwp_info *lp, void *data) | |
1625 | { | |
1626 | lp->resumed = 1; | |
1627 | return 0; | |
1628 | } | |
1629 | ||
1630 | static void | |
1631 | linux_nat_resume (ptid_t ptid, int step, enum target_signal signo) | |
1632 | { | |
1633 | struct lwp_info *lp; | |
1634 | int resume_all; | |
1635 | ||
76f50ad1 DJ |
1636 | if (debug_linux_nat) |
1637 | fprintf_unfiltered (gdb_stdlog, | |
1638 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1639 | step ? "step" : "resume", | |
1640 | target_pid_to_str (ptid), | |
1641 | signo ? strsignal (signo) : "0", | |
1642 | target_pid_to_str (inferior_ptid)); | |
1643 | ||
b84876c2 PA |
1644 | if (target_can_async_p ()) |
1645 | /* Block events while we're here. */ | |
84e46146 | 1646 | linux_nat_async_events (sigchld_sync); |
b84876c2 | 1647 | |
d6b0e80f AC |
1648 | /* A specific PTID means `step only this process id'. */ |
1649 | resume_all = (PIDGET (ptid) == -1); | |
1650 | ||
4c28f408 PA |
1651 | if (non_stop && resume_all) |
1652 | internal_error (__FILE__, __LINE__, | |
1653 | "can't resume all in non-stop mode"); | |
1654 | ||
1655 | if (!non_stop) | |
1656 | { | |
1657 | if (resume_all) | |
1658 | iterate_over_lwps (resume_set_callback, NULL); | |
1659 | else | |
1660 | iterate_over_lwps (resume_clear_callback, NULL); | |
1661 | } | |
d6b0e80f AC |
1662 | |
1663 | /* If PID is -1, it's the current inferior that should be | |
1664 | handled specially. */ | |
1665 | if (PIDGET (ptid) == -1) | |
1666 | ptid = inferior_ptid; | |
1667 | ||
1668 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1669 | gdb_assert (lp != NULL); |
d6b0e80f | 1670 | |
4c28f408 | 1671 | /* Convert to something the lower layer understands. */ |
9f0bdab8 | 1672 | ptid = pid_to_ptid (GET_LWP (lp->ptid)); |
d6b0e80f | 1673 | |
9f0bdab8 DJ |
1674 | /* Remember if we're stepping. */ |
1675 | lp->step = step; | |
d6b0e80f | 1676 | |
9f0bdab8 DJ |
1677 | /* Mark this LWP as resumed. */ |
1678 | lp->resumed = 1; | |
76f50ad1 | 1679 | |
9f0bdab8 DJ |
1680 | /* If we have a pending wait status for this thread, there is no |
1681 | point in resuming the process. But first make sure that | |
1682 | linux_nat_wait won't preemptively handle the event - we | |
1683 | should never take this short-circuit if we are going to | |
1684 | leave LP running, since we have skipped resuming all the | |
1685 | other threads. This bit of code needs to be synchronized | |
1686 | with linux_nat_wait. */ | |
76f50ad1 | 1687 | |
710151dd PA |
1688 | /* In async mode, we never have pending wait status. */ |
1689 | if (target_can_async_p () && lp->status) | |
1690 | internal_error (__FILE__, __LINE__, "Pending status in async mode"); | |
1691 | ||
9f0bdab8 DJ |
1692 | if (lp->status && WIFSTOPPED (lp->status)) |
1693 | { | |
1694 | int saved_signo = target_signal_from_host (WSTOPSIG (lp->status)); | |
76f50ad1 | 1695 | |
9f0bdab8 DJ |
1696 | if (signal_stop_state (saved_signo) == 0 |
1697 | && signal_print_state (saved_signo) == 0 | |
1698 | && signal_pass_state (saved_signo) == 1) | |
d6b0e80f | 1699 | { |
9f0bdab8 DJ |
1700 | if (debug_linux_nat) |
1701 | fprintf_unfiltered (gdb_stdlog, | |
1702 | "LLR: Not short circuiting for ignored " | |
1703 | "status 0x%x\n", lp->status); | |
1704 | ||
d6b0e80f AC |
1705 | /* FIXME: What should we do if we are supposed to continue |
1706 | this thread with a signal? */ | |
1707 | gdb_assert (signo == TARGET_SIGNAL_0); | |
9f0bdab8 DJ |
1708 | signo = saved_signo; |
1709 | lp->status = 0; | |
1710 | } | |
1711 | } | |
76f50ad1 | 1712 | |
9f0bdab8 DJ |
1713 | if (lp->status) |
1714 | { | |
1715 | /* FIXME: What should we do if we are supposed to continue | |
1716 | this thread with a signal? */ | |
1717 | gdb_assert (signo == TARGET_SIGNAL_0); | |
76f50ad1 | 1718 | |
9f0bdab8 DJ |
1719 | if (debug_linux_nat) |
1720 | fprintf_unfiltered (gdb_stdlog, | |
1721 | "LLR: Short circuiting for status 0x%x\n", | |
1722 | lp->status); | |
d6b0e80f | 1723 | |
9f0bdab8 | 1724 | return; |
d6b0e80f AC |
1725 | } |
1726 | ||
9f0bdab8 DJ |
1727 | /* Mark LWP as not stopped to prevent it from being continued by |
1728 | resume_callback. */ | |
1729 | lp->stopped = 0; | |
1730 | ||
d6b0e80f AC |
1731 | if (resume_all) |
1732 | iterate_over_lwps (resume_callback, NULL); | |
1733 | ||
10d6c8cd | 1734 | linux_ops->to_resume (ptid, step, signo); |
9f0bdab8 DJ |
1735 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
1736 | ||
d6b0e80f AC |
1737 | if (debug_linux_nat) |
1738 | fprintf_unfiltered (gdb_stdlog, | |
1739 | "LLR: %s %s, %s (resume event thread)\n", | |
1740 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1741 | target_pid_to_str (ptid), | |
1742 | signo ? strsignal (signo) : "0"); | |
b84876c2 PA |
1743 | |
1744 | if (target_can_async_p ()) | |
8ea051c5 | 1745 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1746 | } |
1747 | ||
1748 | /* Issue kill to specified lwp. */ | |
1749 | ||
1750 | static int tkill_failed; | |
1751 | ||
1752 | static int | |
1753 | kill_lwp (int lwpid, int signo) | |
1754 | { | |
1755 | errno = 0; | |
1756 | ||
1757 | /* Use tkill, if possible, in case we are using nptl threads. If tkill | |
1758 | fails, then we are not using nptl threads and we should be using kill. */ | |
1759 | ||
1760 | #ifdef HAVE_TKILL_SYSCALL | |
1761 | if (!tkill_failed) | |
1762 | { | |
1763 | int ret = syscall (__NR_tkill, lwpid, signo); | |
1764 | if (errno != ENOSYS) | |
1765 | return ret; | |
1766 | errno = 0; | |
1767 | tkill_failed = 1; | |
1768 | } | |
1769 | #endif | |
1770 | ||
1771 | return kill (lwpid, signo); | |
1772 | } | |
1773 | ||
3d799a95 DJ |
1774 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1775 | event, we need to add the new LWP to our list (and not report the | |
1776 | trap to higher layers). This function returns non-zero if the | |
1777 | event should be ignored and we should wait again. If STOPPING is | |
1778 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1779 | |
1780 | static int | |
3d799a95 DJ |
1781 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1782 | int stopping) | |
d6b0e80f | 1783 | { |
3d799a95 DJ |
1784 | int pid = GET_LWP (lp->ptid); |
1785 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1786 | struct lwp_info *new_lp = NULL; | |
1787 | int event = status >> 16; | |
d6b0e80f | 1788 | |
3d799a95 DJ |
1789 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1790 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1791 | { |
3d799a95 DJ |
1792 | unsigned long new_pid; |
1793 | int ret; | |
1794 | ||
1795 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1796 | |
3d799a95 DJ |
1797 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1798 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1799 | { | |
1800 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1801 | hits the SIGSTOP, but we're already attached. */ | |
1802 | ret = my_waitpid (new_pid, &status, | |
1803 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
1804 | if (ret == -1) | |
1805 | perror_with_name (_("waiting for new child")); | |
1806 | else if (ret != new_pid) | |
1807 | internal_error (__FILE__, __LINE__, | |
1808 | _("wait returned unexpected PID %d"), ret); | |
1809 | else if (!WIFSTOPPED (status)) | |
1810 | internal_error (__FILE__, __LINE__, | |
1811 | _("wait returned unexpected status 0x%x"), status); | |
1812 | } | |
1813 | ||
3a3e9ee3 | 1814 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 DJ |
1815 | |
1816 | if (event == PTRACE_EVENT_FORK) | |
1817 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
1818 | else if (event == PTRACE_EVENT_VFORK) | |
1819 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 1820 | else |
3d799a95 | 1821 | { |
4c28f408 PA |
1822 | struct cleanup *old_chain; |
1823 | ||
3d799a95 DJ |
1824 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
1825 | new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid))); | |
1826 | new_lp->cloned = 1; | |
4c28f408 | 1827 | new_lp->stopped = 1; |
d6b0e80f | 1828 | |
3d799a95 DJ |
1829 | if (WSTOPSIG (status) != SIGSTOP) |
1830 | { | |
1831 | /* This can happen if someone starts sending signals to | |
1832 | the new thread before it gets a chance to run, which | |
1833 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
1834 | This is an unlikely case, and harder to handle for | |
1835 | fork / vfork than for clone, so we do not try - but | |
1836 | we handle it for clone events here. We'll send | |
1837 | the other signal on to the thread below. */ | |
1838 | ||
1839 | new_lp->signalled = 1; | |
1840 | } | |
1841 | else | |
1842 | status = 0; | |
d6b0e80f | 1843 | |
4c28f408 | 1844 | if (non_stop) |
3d799a95 | 1845 | { |
4c28f408 PA |
1846 | /* Add the new thread to GDB's lists as soon as possible |
1847 | so that: | |
1848 | ||
1849 | 1) the frontend doesn't have to wait for a stop to | |
1850 | display them, and, | |
1851 | ||
1852 | 2) we tag it with the correct running state. */ | |
1853 | ||
1854 | /* If the thread_db layer is active, let it know about | |
1855 | this new thread, and add it to GDB's list. */ | |
1856 | if (!thread_db_attach_lwp (new_lp->ptid)) | |
1857 | { | |
1858 | /* We're not using thread_db. Add it to GDB's | |
1859 | list. */ | |
1860 | target_post_attach (GET_LWP (new_lp->ptid)); | |
1861 | add_thread (new_lp->ptid); | |
1862 | } | |
1863 | ||
1864 | if (!stopping) | |
1865 | { | |
1866 | set_running (new_lp->ptid, 1); | |
1867 | set_executing (new_lp->ptid, 1); | |
1868 | } | |
1869 | } | |
1870 | ||
1871 | if (!stopping) | |
1872 | { | |
1873 | new_lp->stopped = 0; | |
3d799a95 | 1874 | new_lp->resumed = 1; |
4c28f408 | 1875 | ptrace (PTRACE_CONT, new_pid, 0, |
3d799a95 DJ |
1876 | status ? WSTOPSIG (status) : 0); |
1877 | } | |
d6b0e80f | 1878 | |
3d799a95 DJ |
1879 | if (debug_linux_nat) |
1880 | fprintf_unfiltered (gdb_stdlog, | |
1881 | "LHEW: Got clone event from LWP %ld, resuming\n", | |
1882 | GET_LWP (lp->ptid)); | |
1883 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1884 | ||
1885 | return 1; | |
1886 | } | |
1887 | ||
1888 | return 0; | |
d6b0e80f AC |
1889 | } |
1890 | ||
3d799a95 DJ |
1891 | if (event == PTRACE_EVENT_EXEC) |
1892 | { | |
1893 | ourstatus->kind = TARGET_WAITKIND_EXECD; | |
1894 | ourstatus->value.execd_pathname | |
6d8fd2b7 | 1895 | = xstrdup (linux_child_pid_to_exec_file (pid)); |
3d799a95 DJ |
1896 | |
1897 | if (linux_parent_pid) | |
1898 | { | |
1899 | detach_breakpoints (linux_parent_pid); | |
1900 | ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0); | |
1901 | ||
1902 | linux_parent_pid = 0; | |
1903 | } | |
1904 | ||
25b22b0a PA |
1905 | /* At this point, all inserted breakpoints are gone. Doing this |
1906 | as soon as we detect an exec prevents the badness of deleting | |
1907 | a breakpoint writing the current "shadow contents" to lift | |
1908 | the bp. That shadow is NOT valid after an exec. | |
1909 | ||
1910 | Note that we have to do this after the detach_breakpoints | |
1911 | call above, otherwise breakpoints wouldn't be lifted from the | |
1912 | parent on a vfork, because detach_breakpoints would think | |
1913 | that breakpoints are not inserted. */ | |
1914 | mark_breakpoints_out (); | |
3d799a95 DJ |
1915 | return 0; |
1916 | } | |
1917 | ||
1918 | internal_error (__FILE__, __LINE__, | |
1919 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
1920 | } |
1921 | ||
1922 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
1923 | exited. */ | |
1924 | ||
1925 | static int | |
1926 | wait_lwp (struct lwp_info *lp) | |
1927 | { | |
1928 | pid_t pid; | |
1929 | int status; | |
1930 | int thread_dead = 0; | |
1931 | ||
1932 | gdb_assert (!lp->stopped); | |
1933 | gdb_assert (lp->status == 0); | |
1934 | ||
58aecb61 | 1935 | pid = my_waitpid (GET_LWP (lp->ptid), &status, 0); |
d6b0e80f AC |
1936 | if (pid == -1 && errno == ECHILD) |
1937 | { | |
58aecb61 | 1938 | pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE); |
d6b0e80f AC |
1939 | if (pid == -1 && errno == ECHILD) |
1940 | { | |
1941 | /* The thread has previously exited. We need to delete it | |
1942 | now because, for some vendor 2.4 kernels with NPTL | |
1943 | support backported, there won't be an exit event unless | |
1944 | it is the main thread. 2.6 kernels will report an exit | |
1945 | event for each thread that exits, as expected. */ | |
1946 | thread_dead = 1; | |
1947 | if (debug_linux_nat) | |
1948 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
1949 | target_pid_to_str (lp->ptid)); | |
1950 | } | |
1951 | } | |
1952 | ||
1953 | if (!thread_dead) | |
1954 | { | |
1955 | gdb_assert (pid == GET_LWP (lp->ptid)); | |
1956 | ||
1957 | if (debug_linux_nat) | |
1958 | { | |
1959 | fprintf_unfiltered (gdb_stdlog, | |
1960 | "WL: waitpid %s received %s\n", | |
1961 | target_pid_to_str (lp->ptid), | |
1962 | status_to_str (status)); | |
1963 | } | |
1964 | } | |
1965 | ||
1966 | /* Check if the thread has exited. */ | |
1967 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
1968 | { | |
1969 | thread_dead = 1; | |
1970 | if (debug_linux_nat) | |
1971 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
1972 | target_pid_to_str (lp->ptid)); | |
1973 | } | |
1974 | ||
1975 | if (thread_dead) | |
1976 | { | |
e26af52f | 1977 | exit_lwp (lp); |
d6b0e80f AC |
1978 | return 0; |
1979 | } | |
1980 | ||
1981 | gdb_assert (WIFSTOPPED (status)); | |
1982 | ||
1983 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
1984 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
1985 | { | |
1986 | if (debug_linux_nat) | |
1987 | fprintf_unfiltered (gdb_stdlog, | |
1988 | "WL: Handling extended status 0x%06x\n", | |
1989 | status); | |
3d799a95 | 1990 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
1991 | return wait_lwp (lp); |
1992 | } | |
1993 | ||
1994 | return status; | |
1995 | } | |
1996 | ||
9f0bdab8 DJ |
1997 | /* Save the most recent siginfo for LP. This is currently only called |
1998 | for SIGTRAP; some ports use the si_addr field for | |
1999 | target_stopped_data_address. In the future, it may also be used to | |
2000 | restore the siginfo of requeued signals. */ | |
2001 | ||
2002 | static void | |
2003 | save_siginfo (struct lwp_info *lp) | |
2004 | { | |
2005 | errno = 0; | |
2006 | ptrace (PTRACE_GETSIGINFO, GET_LWP (lp->ptid), | |
2007 | (PTRACE_TYPE_ARG3) 0, &lp->siginfo); | |
2008 | ||
2009 | if (errno != 0) | |
2010 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); | |
2011 | } | |
2012 | ||
d6b0e80f AC |
2013 | /* Send a SIGSTOP to LP. */ |
2014 | ||
2015 | static int | |
2016 | stop_callback (struct lwp_info *lp, void *data) | |
2017 | { | |
2018 | if (!lp->stopped && !lp->signalled) | |
2019 | { | |
2020 | int ret; | |
2021 | ||
2022 | if (debug_linux_nat) | |
2023 | { | |
2024 | fprintf_unfiltered (gdb_stdlog, | |
2025 | "SC: kill %s **<SIGSTOP>**\n", | |
2026 | target_pid_to_str (lp->ptid)); | |
2027 | } | |
2028 | errno = 0; | |
2029 | ret = kill_lwp (GET_LWP (lp->ptid), SIGSTOP); | |
2030 | if (debug_linux_nat) | |
2031 | { | |
2032 | fprintf_unfiltered (gdb_stdlog, | |
2033 | "SC: lwp kill %d %s\n", | |
2034 | ret, | |
2035 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2036 | } | |
2037 | ||
2038 | lp->signalled = 1; | |
2039 | gdb_assert (lp->status == 0); | |
2040 | } | |
2041 | ||
2042 | return 0; | |
2043 | } | |
2044 | ||
57380f4e | 2045 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2046 | |
2047 | static int | |
57380f4e DJ |
2048 | linux_nat_has_pending_sigint (int pid) |
2049 | { | |
2050 | sigset_t pending, blocked, ignored; | |
2051 | int i; | |
2052 | ||
2053 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2054 | ||
2055 | if (sigismember (&pending, SIGINT) | |
2056 | && !sigismember (&ignored, SIGINT)) | |
2057 | return 1; | |
2058 | ||
2059 | return 0; | |
2060 | } | |
2061 | ||
2062 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2063 | ||
2064 | static int | |
2065 | set_ignore_sigint (struct lwp_info *lp, void *data) | |
d6b0e80f | 2066 | { |
57380f4e DJ |
2067 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2068 | flag to consume the next one. */ | |
2069 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2070 | && WSTOPSIG (lp->status) == SIGINT) | |
2071 | lp->status = 0; | |
2072 | else | |
2073 | lp->ignore_sigint = 1; | |
2074 | ||
2075 | return 0; | |
2076 | } | |
2077 | ||
2078 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2079 | This function is called after we know the LWP has stopped; if the LWP | |
2080 | stopped before the expected SIGINT was delivered, then it will never have | |
2081 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2082 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2083 | |
57380f4e DJ |
2084 | static void |
2085 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2086 | { | |
2087 | if (!lp->ignore_sigint) | |
2088 | return; | |
2089 | ||
2090 | if (!linux_nat_has_pending_sigint (GET_LWP (lp->ptid))) | |
2091 | { | |
2092 | if (debug_linux_nat) | |
2093 | fprintf_unfiltered (gdb_stdlog, | |
2094 | "MCIS: Clearing bogus flag for %s\n", | |
2095 | target_pid_to_str (lp->ptid)); | |
2096 | lp->ignore_sigint = 0; | |
2097 | } | |
2098 | } | |
2099 | ||
2100 | /* Wait until LP is stopped. */ | |
2101 | ||
2102 | static int | |
2103 | stop_wait_callback (struct lwp_info *lp, void *data) | |
2104 | { | |
d6b0e80f AC |
2105 | if (!lp->stopped) |
2106 | { | |
2107 | int status; | |
2108 | ||
2109 | status = wait_lwp (lp); | |
2110 | if (status == 0) | |
2111 | return 0; | |
2112 | ||
57380f4e DJ |
2113 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2114 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2115 | { |
57380f4e | 2116 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2117 | |
2118 | errno = 0; | |
2119 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2120 | if (debug_linux_nat) | |
2121 | fprintf_unfiltered (gdb_stdlog, | |
57380f4e | 2122 | "PTRACE_CONT %s, 0, 0 (%s) (discarding SIGINT)\n", |
d6b0e80f AC |
2123 | target_pid_to_str (lp->ptid), |
2124 | errno ? safe_strerror (errno) : "OK"); | |
2125 | ||
57380f4e | 2126 | return stop_wait_callback (lp, NULL); |
d6b0e80f AC |
2127 | } |
2128 | ||
57380f4e DJ |
2129 | maybe_clear_ignore_sigint (lp); |
2130 | ||
d6b0e80f AC |
2131 | if (WSTOPSIG (status) != SIGSTOP) |
2132 | { | |
2133 | if (WSTOPSIG (status) == SIGTRAP) | |
2134 | { | |
2135 | /* If a LWP other than the LWP that we're reporting an | |
2136 | event for has hit a GDB breakpoint (as opposed to | |
2137 | some random trap signal), then just arrange for it to | |
2138 | hit it again later. We don't keep the SIGTRAP status | |
2139 | and don't forward the SIGTRAP signal to the LWP. We | |
2140 | will handle the current event, eventually we will | |
2141 | resume all LWPs, and this one will get its breakpoint | |
2142 | trap again. | |
2143 | ||
2144 | If we do not do this, then we run the risk that the | |
2145 | user will delete or disable the breakpoint, but the | |
2146 | thread will have already tripped on it. */ | |
2147 | ||
9f0bdab8 DJ |
2148 | /* Save the trap's siginfo in case we need it later. */ |
2149 | save_siginfo (lp); | |
2150 | ||
d6b0e80f AC |
2151 | /* Now resume this LWP and get the SIGSTOP event. */ |
2152 | errno = 0; | |
2153 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2154 | if (debug_linux_nat) | |
2155 | { | |
2156 | fprintf_unfiltered (gdb_stdlog, | |
2157 | "PTRACE_CONT %s, 0, 0 (%s)\n", | |
2158 | target_pid_to_str (lp->ptid), | |
2159 | errno ? safe_strerror (errno) : "OK"); | |
2160 | ||
2161 | fprintf_unfiltered (gdb_stdlog, | |
2162 | "SWC: Candidate SIGTRAP event in %s\n", | |
2163 | target_pid_to_str (lp->ptid)); | |
2164 | } | |
710151dd PA |
2165 | /* Hold this event/waitstatus while we check to see if |
2166 | there are any more (we still want to get that SIGSTOP). */ | |
57380f4e | 2167 | stop_wait_callback (lp, NULL); |
710151dd PA |
2168 | |
2169 | if (target_can_async_p ()) | |
d6b0e80f | 2170 | { |
710151dd PA |
2171 | /* Don't leave a pending wait status in async mode. |
2172 | Retrigger the breakpoint. */ | |
2173 | if (!cancel_breakpoint (lp)) | |
d6b0e80f | 2174 | { |
710151dd PA |
2175 | /* There was no gdb breakpoint set at pc. Put |
2176 | the event back in the queue. */ | |
2177 | if (debug_linux_nat) | |
2178 | fprintf_unfiltered (gdb_stdlog, | |
2179 | "SWC: kill %s, %s\n", | |
2180 | target_pid_to_str (lp->ptid), | |
2181 | status_to_str ((int) status)); | |
2182 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
2183 | } | |
2184 | } | |
2185 | else | |
2186 | { | |
2187 | /* Hold the SIGTRAP for handling by | |
2188 | linux_nat_wait. */ | |
2189 | /* If there's another event, throw it back into the | |
2190 | queue. */ | |
2191 | if (lp->status) | |
2192 | { | |
2193 | if (debug_linux_nat) | |
2194 | fprintf_unfiltered (gdb_stdlog, | |
2195 | "SWC: kill %s, %s\n", | |
2196 | target_pid_to_str (lp->ptid), | |
2197 | status_to_str ((int) status)); | |
2198 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status)); | |
d6b0e80f | 2199 | } |
710151dd PA |
2200 | /* Save the sigtrap event. */ |
2201 | lp->status = status; | |
d6b0e80f | 2202 | } |
d6b0e80f AC |
2203 | return 0; |
2204 | } | |
2205 | else | |
2206 | { | |
2207 | /* The thread was stopped with a signal other than | |
2208 | SIGSTOP, and didn't accidentally trip a breakpoint. */ | |
2209 | ||
2210 | if (debug_linux_nat) | |
2211 | { | |
2212 | fprintf_unfiltered (gdb_stdlog, | |
2213 | "SWC: Pending event %s in %s\n", | |
2214 | status_to_str ((int) status), | |
2215 | target_pid_to_str (lp->ptid)); | |
2216 | } | |
2217 | /* Now resume this LWP and get the SIGSTOP event. */ | |
2218 | errno = 0; | |
2219 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2220 | if (debug_linux_nat) | |
2221 | fprintf_unfiltered (gdb_stdlog, | |
2222 | "SWC: PTRACE_CONT %s, 0, 0 (%s)\n", | |
2223 | target_pid_to_str (lp->ptid), | |
2224 | errno ? safe_strerror (errno) : "OK"); | |
2225 | ||
2226 | /* Hold this event/waitstatus while we check to see if | |
2227 | there are any more (we still want to get that SIGSTOP). */ | |
57380f4e | 2228 | stop_wait_callback (lp, NULL); |
710151dd PA |
2229 | |
2230 | /* If the lp->status field is still empty, use it to | |
2231 | hold this event. If not, then this event must be | |
2232 | returned to the event queue of the LWP. */ | |
2233 | if (lp->status || target_can_async_p ()) | |
d6b0e80f AC |
2234 | { |
2235 | if (debug_linux_nat) | |
2236 | { | |
2237 | fprintf_unfiltered (gdb_stdlog, | |
2238 | "SWC: kill %s, %s\n", | |
2239 | target_pid_to_str (lp->ptid), | |
2240 | status_to_str ((int) status)); | |
2241 | } | |
2242 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
2243 | } | |
710151dd PA |
2244 | else |
2245 | lp->status = status; | |
d6b0e80f AC |
2246 | return 0; |
2247 | } | |
2248 | } | |
2249 | else | |
2250 | { | |
2251 | /* We caught the SIGSTOP that we intended to catch, so | |
2252 | there's no SIGSTOP pending. */ | |
2253 | lp->stopped = 1; | |
2254 | lp->signalled = 0; | |
2255 | } | |
2256 | } | |
2257 | ||
2258 | return 0; | |
2259 | } | |
2260 | ||
d6b0e80f AC |
2261 | /* Return non-zero if LP has a wait status pending. */ |
2262 | ||
2263 | static int | |
2264 | status_callback (struct lwp_info *lp, void *data) | |
2265 | { | |
2266 | /* Only report a pending wait status if we pretend that this has | |
2267 | indeed been resumed. */ | |
2268 | return (lp->status != 0 && lp->resumed); | |
2269 | } | |
2270 | ||
2271 | /* Return non-zero if LP isn't stopped. */ | |
2272 | ||
2273 | static int | |
2274 | running_callback (struct lwp_info *lp, void *data) | |
2275 | { | |
2276 | return (lp->stopped == 0 || (lp->status != 0 && lp->resumed)); | |
2277 | } | |
2278 | ||
2279 | /* Count the LWP's that have had events. */ | |
2280 | ||
2281 | static int | |
2282 | count_events_callback (struct lwp_info *lp, void *data) | |
2283 | { | |
2284 | int *count = data; | |
2285 | ||
2286 | gdb_assert (count != NULL); | |
2287 | ||
e09490f1 DJ |
2288 | /* Count only resumed LWPs that have a SIGTRAP event pending. */ |
2289 | if (lp->status != 0 && lp->resumed | |
d6b0e80f AC |
2290 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) |
2291 | (*count)++; | |
2292 | ||
2293 | return 0; | |
2294 | } | |
2295 | ||
2296 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2297 | ||
2298 | static int | |
2299 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2300 | { | |
2301 | if (lp->step && lp->status != 0) | |
2302 | return 1; | |
2303 | else | |
2304 | return 0; | |
2305 | } | |
2306 | ||
2307 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2308 | ||
2309 | static int | |
2310 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2311 | { | |
2312 | int *selector = data; | |
2313 | ||
2314 | gdb_assert (selector != NULL); | |
2315 | ||
e09490f1 DJ |
2316 | /* Select only resumed LWPs that have a SIGTRAP event pending. */ |
2317 | if (lp->status != 0 && lp->resumed | |
d6b0e80f AC |
2318 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) |
2319 | if ((*selector)-- == 0) | |
2320 | return 1; | |
2321 | ||
2322 | return 0; | |
2323 | } | |
2324 | ||
710151dd PA |
2325 | static int |
2326 | cancel_breakpoint (struct lwp_info *lp) | |
2327 | { | |
2328 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2329 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2330 | LWP. We will handle the current event, eventually we will resume | |
2331 | this LWP, and this breakpoint will trap again. | |
2332 | ||
2333 | If we do not do this, then we run the risk that the user will | |
2334 | delete or disable the breakpoint, but the LWP will have already | |
2335 | tripped on it. */ | |
2336 | ||
515630c5 UW |
2337 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2338 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2339 | CORE_ADDR pc; | |
2340 | ||
2341 | pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch); | |
2342 | if (breakpoint_inserted_here_p (pc)) | |
710151dd PA |
2343 | { |
2344 | if (debug_linux_nat) | |
2345 | fprintf_unfiltered (gdb_stdlog, | |
2346 | "CB: Push back breakpoint for %s\n", | |
2347 | target_pid_to_str (lp->ptid)); | |
2348 | ||
2349 | /* Back up the PC if necessary. */ | |
515630c5 UW |
2350 | if (gdbarch_decr_pc_after_break (gdbarch)) |
2351 | regcache_write_pc (regcache, pc); | |
2352 | ||
710151dd PA |
2353 | return 1; |
2354 | } | |
2355 | return 0; | |
2356 | } | |
2357 | ||
d6b0e80f AC |
2358 | static int |
2359 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2360 | { | |
2361 | struct lwp_info *event_lp = data; | |
2362 | ||
2363 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2364 | if (lp == event_lp) | |
2365 | return 0; | |
2366 | ||
2367 | /* If a LWP other than the LWP that we're reporting an event for has | |
2368 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2369 | then just arrange for it to hit it again later. We don't keep | |
2370 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2371 | LWP. We will handle the current event, eventually we will resume | |
2372 | all LWPs, and this one will get its breakpoint trap again. | |
2373 | ||
2374 | If we do not do this, then we run the risk that the user will | |
2375 | delete or disable the breakpoint, but the LWP will have already | |
2376 | tripped on it. */ | |
2377 | ||
2378 | if (lp->status != 0 | |
2379 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP | |
710151dd PA |
2380 | && cancel_breakpoint (lp)) |
2381 | /* Throw away the SIGTRAP. */ | |
2382 | lp->status = 0; | |
d6b0e80f AC |
2383 | |
2384 | return 0; | |
2385 | } | |
2386 | ||
2387 | /* Select one LWP out of those that have events pending. */ | |
2388 | ||
2389 | static void | |
2390 | select_event_lwp (struct lwp_info **orig_lp, int *status) | |
2391 | { | |
2392 | int num_events = 0; | |
2393 | int random_selector; | |
2394 | struct lwp_info *event_lp; | |
2395 | ||
ac264b3b | 2396 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2397 | (*orig_lp)->status = *status; |
2398 | ||
2399 | /* Give preference to any LWP that is being single-stepped. */ | |
2400 | event_lp = iterate_over_lwps (select_singlestep_lwp_callback, NULL); | |
2401 | if (event_lp != NULL) | |
2402 | { | |
2403 | if (debug_linux_nat) | |
2404 | fprintf_unfiltered (gdb_stdlog, | |
2405 | "SEL: Select single-step %s\n", | |
2406 | target_pid_to_str (event_lp->ptid)); | |
2407 | } | |
2408 | else | |
2409 | { | |
2410 | /* No single-stepping LWP. Select one at random, out of those | |
2411 | which have had SIGTRAP events. */ | |
2412 | ||
2413 | /* First see how many SIGTRAP events we have. */ | |
2414 | iterate_over_lwps (count_events_callback, &num_events); | |
2415 | ||
2416 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2417 | random_selector = (int) | |
2418 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2419 | ||
2420 | if (debug_linux_nat && num_events > 1) | |
2421 | fprintf_unfiltered (gdb_stdlog, | |
2422 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2423 | num_events, random_selector); | |
2424 | ||
2425 | event_lp = iterate_over_lwps (select_event_lwp_callback, | |
2426 | &random_selector); | |
2427 | } | |
2428 | ||
2429 | if (event_lp != NULL) | |
2430 | { | |
2431 | /* Switch the event LWP. */ | |
2432 | *orig_lp = event_lp; | |
2433 | *status = event_lp->status; | |
2434 | } | |
2435 | ||
2436 | /* Flush the wait status for the event LWP. */ | |
2437 | (*orig_lp)->status = 0; | |
2438 | } | |
2439 | ||
2440 | /* Return non-zero if LP has been resumed. */ | |
2441 | ||
2442 | static int | |
2443 | resumed_callback (struct lwp_info *lp, void *data) | |
2444 | { | |
2445 | return lp->resumed; | |
2446 | } | |
2447 | ||
d6b0e80f AC |
2448 | /* Stop an active thread, verify it still exists, then resume it. */ |
2449 | ||
2450 | static int | |
2451 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2452 | { | |
2453 | struct lwp_info *ptr; | |
2454 | ||
2455 | if (!lp->stopped && !lp->signalled) | |
2456 | { | |
2457 | stop_callback (lp, NULL); | |
2458 | stop_wait_callback (lp, NULL); | |
2459 | /* Resume if the lwp still exists. */ | |
2460 | for (ptr = lwp_list; ptr; ptr = ptr->next) | |
2461 | if (lp == ptr) | |
2462 | { | |
2463 | resume_callback (lp, NULL); | |
2464 | resume_set_callback (lp, NULL); | |
2465 | } | |
2466 | } | |
2467 | return 0; | |
2468 | } | |
2469 | ||
02f3fc28 | 2470 | /* Check if we should go on and pass this event to common code. |
fa2c6a57 | 2471 | Return the affected lwp if we are, or NULL otherwise. */ |
02f3fc28 PA |
2472 | static struct lwp_info * |
2473 | linux_nat_filter_event (int lwpid, int status, int options) | |
2474 | { | |
2475 | struct lwp_info *lp; | |
2476 | ||
2477 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
2478 | ||
2479 | /* Check for stop events reported by a process we didn't already | |
2480 | know about - anything not already in our LWP list. | |
2481 | ||
2482 | If we're expecting to receive stopped processes after | |
2483 | fork, vfork, and clone events, then we'll just add the | |
2484 | new one to our list and go back to waiting for the event | |
2485 | to be reported - the stopped process might be returned | |
2486 | from waitpid before or after the event is. */ | |
2487 | if (WIFSTOPPED (status) && !lp) | |
2488 | { | |
2489 | linux_record_stopped_pid (lwpid, status); | |
2490 | return NULL; | |
2491 | } | |
2492 | ||
2493 | /* Make sure we don't report an event for the exit of an LWP not in | |
2494 | our list, i.e. not part of the current process. This can happen | |
2495 | if we detach from a program we original forked and then it | |
2496 | exits. */ | |
2497 | if (!WIFSTOPPED (status) && !lp) | |
2498 | return NULL; | |
2499 | ||
2500 | /* NOTE drow/2003-06-17: This code seems to be meant for debugging | |
2501 | CLONE_PTRACE processes which do not use the thread library - | |
2502 | otherwise we wouldn't find the new LWP this way. That doesn't | |
2503 | currently work, and the following code is currently unreachable | |
2504 | due to the two blocks above. If it's fixed some day, this code | |
2505 | should be broken out into a function so that we can also pick up | |
2506 | LWPs from the new interface. */ | |
2507 | if (!lp) | |
2508 | { | |
2509 | lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid))); | |
2510 | if (options & __WCLONE) | |
2511 | lp->cloned = 1; | |
2512 | ||
2513 | gdb_assert (WIFSTOPPED (status) | |
2514 | && WSTOPSIG (status) == SIGSTOP); | |
2515 | lp->signalled = 1; | |
2516 | ||
2517 | if (!in_thread_list (inferior_ptid)) | |
2518 | { | |
2519 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2520 | GET_PID (inferior_ptid)); | |
2521 | add_thread (inferior_ptid); | |
2522 | } | |
2523 | ||
2524 | add_thread (lp->ptid); | |
2525 | } | |
2526 | ||
2527 | /* Save the trap's siginfo in case we need it later. */ | |
2528 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) | |
2529 | save_siginfo (lp); | |
2530 | ||
2531 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
2532 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2533 | { | |
2534 | if (debug_linux_nat) | |
2535 | fprintf_unfiltered (gdb_stdlog, | |
2536 | "LLW: Handling extended status 0x%06x\n", | |
2537 | status); | |
2538 | if (linux_handle_extended_wait (lp, status, 0)) | |
2539 | return NULL; | |
2540 | } | |
2541 | ||
2542 | /* Check if the thread has exited. */ | |
2543 | if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1) | |
2544 | { | |
2545 | /* If this is the main thread, we must stop all threads and | |
2546 | verify if they are still alive. This is because in the nptl | |
2547 | thread model, there is no signal issued for exiting LWPs | |
2548 | other than the main thread. We only get the main thread exit | |
2549 | signal once all child threads have already exited. If we | |
2550 | stop all the threads and use the stop_wait_callback to check | |
2551 | if they have exited we can determine whether this signal | |
2552 | should be ignored or whether it means the end of the debugged | |
2553 | application, regardless of which threading model is being | |
2554 | used. */ | |
2555 | if (GET_PID (lp->ptid) == GET_LWP (lp->ptid)) | |
2556 | { | |
2557 | lp->stopped = 1; | |
2558 | iterate_over_lwps (stop_and_resume_callback, NULL); | |
2559 | } | |
2560 | ||
2561 | if (debug_linux_nat) | |
2562 | fprintf_unfiltered (gdb_stdlog, | |
2563 | "LLW: %s exited.\n", | |
2564 | target_pid_to_str (lp->ptid)); | |
2565 | ||
2566 | exit_lwp (lp); | |
2567 | ||
2568 | /* If there is at least one more LWP, then the exit signal was | |
2569 | not the end of the debugged application and should be | |
2570 | ignored. */ | |
2571 | if (num_lwps > 0) | |
4c28f408 | 2572 | return NULL; |
02f3fc28 PA |
2573 | } |
2574 | ||
2575 | /* Check if the current LWP has previously exited. In the nptl | |
2576 | thread model, LWPs other than the main thread do not issue | |
2577 | signals when they exit so we must check whenever the thread has | |
2578 | stopped. A similar check is made in stop_wait_callback(). */ | |
2579 | if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid)) | |
2580 | { | |
2581 | if (debug_linux_nat) | |
2582 | fprintf_unfiltered (gdb_stdlog, | |
2583 | "LLW: %s exited.\n", | |
2584 | target_pid_to_str (lp->ptid)); | |
2585 | ||
2586 | exit_lwp (lp); | |
2587 | ||
2588 | /* Make sure there is at least one thread running. */ | |
2589 | gdb_assert (iterate_over_lwps (running_callback, NULL)); | |
2590 | ||
2591 | /* Discard the event. */ | |
2592 | return NULL; | |
2593 | } | |
2594 | ||
2595 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
2596 | an attempt to stop an LWP. */ | |
2597 | if (lp->signalled | |
2598 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
2599 | { | |
2600 | if (debug_linux_nat) | |
2601 | fprintf_unfiltered (gdb_stdlog, | |
2602 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
2603 | target_pid_to_str (lp->ptid)); | |
2604 | ||
2605 | /* This is a delayed SIGSTOP. */ | |
2606 | lp->signalled = 0; | |
2607 | ||
2608 | registers_changed (); | |
2609 | ||
2610 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), | |
2611 | lp->step, TARGET_SIGNAL_0); | |
2612 | if (debug_linux_nat) | |
2613 | fprintf_unfiltered (gdb_stdlog, | |
2614 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
2615 | lp->step ? | |
2616 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2617 | target_pid_to_str (lp->ptid)); | |
2618 | ||
2619 | lp->stopped = 0; | |
2620 | gdb_assert (lp->resumed); | |
2621 | ||
2622 | /* Discard the event. */ | |
2623 | return NULL; | |
2624 | } | |
2625 | ||
57380f4e DJ |
2626 | /* Make sure we don't report a SIGINT that we have already displayed |
2627 | for another thread. */ | |
2628 | if (lp->ignore_sigint | |
2629 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
2630 | { | |
2631 | if (debug_linux_nat) | |
2632 | fprintf_unfiltered (gdb_stdlog, | |
2633 | "LLW: Delayed SIGINT caught for %s.\n", | |
2634 | target_pid_to_str (lp->ptid)); | |
2635 | ||
2636 | /* This is a delayed SIGINT. */ | |
2637 | lp->ignore_sigint = 0; | |
2638 | ||
2639 | registers_changed (); | |
2640 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), | |
2641 | lp->step, TARGET_SIGNAL_0); | |
2642 | if (debug_linux_nat) | |
2643 | fprintf_unfiltered (gdb_stdlog, | |
2644 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
2645 | lp->step ? | |
2646 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2647 | target_pid_to_str (lp->ptid)); | |
2648 | ||
2649 | lp->stopped = 0; | |
2650 | gdb_assert (lp->resumed); | |
2651 | ||
2652 | /* Discard the event. */ | |
2653 | return NULL; | |
2654 | } | |
2655 | ||
02f3fc28 PA |
2656 | /* An interesting event. */ |
2657 | gdb_assert (lp); | |
2658 | return lp; | |
2659 | } | |
2660 | ||
b84876c2 PA |
2661 | /* Get the events stored in the pipe into the local queue, so they are |
2662 | accessible to queued_waitpid. We need to do this, since it is not | |
2663 | always the case that the event at the head of the pipe is the event | |
2664 | we want. */ | |
2665 | ||
2666 | static void | |
2667 | pipe_to_local_event_queue (void) | |
2668 | { | |
2669 | if (debug_linux_nat_async) | |
2670 | fprintf_unfiltered (gdb_stdlog, | |
2671 | "PTLEQ: linux_nat_num_queued_events(%d)\n", | |
2672 | linux_nat_num_queued_events); | |
2673 | while (linux_nat_num_queued_events) | |
2674 | { | |
2675 | int lwpid, status, options; | |
b84876c2 | 2676 | lwpid = linux_nat_event_pipe_pop (&status, &options); |
b84876c2 PA |
2677 | gdb_assert (lwpid > 0); |
2678 | push_waitpid (lwpid, status, options); | |
2679 | } | |
2680 | } | |
2681 | ||
2682 | /* Get the unprocessed events stored in the local queue back into the | |
2683 | pipe, so the event loop realizes there's something else to | |
2684 | process. */ | |
2685 | ||
2686 | static void | |
2687 | local_event_queue_to_pipe (void) | |
2688 | { | |
2689 | struct waitpid_result *w = waitpid_queue; | |
2690 | while (w) | |
2691 | { | |
2692 | struct waitpid_result *next = w->next; | |
2693 | linux_nat_event_pipe_push (w->pid, | |
2694 | w->status, | |
2695 | w->options); | |
2696 | xfree (w); | |
2697 | w = next; | |
2698 | } | |
2699 | waitpid_queue = NULL; | |
2700 | ||
2701 | if (debug_linux_nat_async) | |
2702 | fprintf_unfiltered (gdb_stdlog, | |
2703 | "LEQTP: linux_nat_num_queued_events(%d)\n", | |
2704 | linux_nat_num_queued_events); | |
2705 | } | |
2706 | ||
d6b0e80f AC |
2707 | static ptid_t |
2708 | linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
2709 | { | |
2710 | struct lwp_info *lp = NULL; | |
2711 | int options = 0; | |
2712 | int status = 0; | |
2713 | pid_t pid = PIDGET (ptid); | |
d6b0e80f | 2714 | |
b84876c2 PA |
2715 | if (debug_linux_nat_async) |
2716 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); | |
2717 | ||
f973ed9c DJ |
2718 | /* The first time we get here after starting a new inferior, we may |
2719 | not have added it to the LWP list yet - this is the earliest | |
2720 | moment at which we know its PID. */ | |
2721 | if (num_lwps == 0) | |
2722 | { | |
2723 | gdb_assert (!is_lwp (inferior_ptid)); | |
2724 | ||
2725 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2726 | GET_PID (inferior_ptid)); | |
2727 | lp = add_lwp (inferior_ptid); | |
2728 | lp->resumed = 1; | |
403fe197 PA |
2729 | /* Add the main thread to GDB's thread list. */ |
2730 | add_thread_silent (lp->ptid); | |
4c28f408 PA |
2731 | set_running (lp->ptid, 1); |
2732 | set_executing (lp->ptid, 1); | |
f973ed9c DJ |
2733 | } |
2734 | ||
84e46146 PA |
2735 | /* Block events while we're here. */ |
2736 | linux_nat_async_events (sigchld_sync); | |
d6b0e80f AC |
2737 | |
2738 | retry: | |
2739 | ||
f973ed9c DJ |
2740 | /* Make sure there is at least one LWP that has been resumed. */ |
2741 | gdb_assert (iterate_over_lwps (resumed_callback, NULL)); | |
d6b0e80f AC |
2742 | |
2743 | /* First check if there is a LWP with a wait status pending. */ | |
2744 | if (pid == -1) | |
2745 | { | |
2746 | /* Any LWP that's been resumed will do. */ | |
2747 | lp = iterate_over_lwps (status_callback, NULL); | |
2748 | if (lp) | |
2749 | { | |
710151dd PA |
2750 | if (target_can_async_p ()) |
2751 | internal_error (__FILE__, __LINE__, | |
2752 | "Found an LWP with a pending status in async mode."); | |
2753 | ||
d6b0e80f AC |
2754 | status = lp->status; |
2755 | lp->status = 0; | |
2756 | ||
2757 | if (debug_linux_nat && status) | |
2758 | fprintf_unfiltered (gdb_stdlog, | |
2759 | "LLW: Using pending wait status %s for %s.\n", | |
2760 | status_to_str (status), | |
2761 | target_pid_to_str (lp->ptid)); | |
2762 | } | |
2763 | ||
b84876c2 | 2764 | /* But if we don't find one, we'll have to wait, and check both |
d6b0e80f AC |
2765 | cloned and uncloned processes. We start with the cloned |
2766 | processes. */ | |
2767 | options = __WCLONE | WNOHANG; | |
2768 | } | |
2769 | else if (is_lwp (ptid)) | |
2770 | { | |
2771 | if (debug_linux_nat) | |
2772 | fprintf_unfiltered (gdb_stdlog, | |
2773 | "LLW: Waiting for specific LWP %s.\n", | |
2774 | target_pid_to_str (ptid)); | |
2775 | ||
2776 | /* We have a specific LWP to check. */ | |
2777 | lp = find_lwp_pid (ptid); | |
2778 | gdb_assert (lp); | |
2779 | status = lp->status; | |
2780 | lp->status = 0; | |
2781 | ||
2782 | if (debug_linux_nat && status) | |
2783 | fprintf_unfiltered (gdb_stdlog, | |
2784 | "LLW: Using pending wait status %s for %s.\n", | |
2785 | status_to_str (status), | |
2786 | target_pid_to_str (lp->ptid)); | |
2787 | ||
2788 | /* If we have to wait, take into account whether PID is a cloned | |
2789 | process or not. And we have to convert it to something that | |
2790 | the layer beneath us can understand. */ | |
2791 | options = lp->cloned ? __WCLONE : 0; | |
2792 | pid = GET_LWP (ptid); | |
2793 | } | |
2794 | ||
2795 | if (status && lp->signalled) | |
2796 | { | |
2797 | /* A pending SIGSTOP may interfere with the normal stream of | |
2798 | events. In a typical case where interference is a problem, | |
2799 | we have a SIGSTOP signal pending for LWP A while | |
2800 | single-stepping it, encounter an event in LWP B, and take the | |
2801 | pending SIGSTOP while trying to stop LWP A. After processing | |
2802 | the event in LWP B, LWP A is continued, and we'll never see | |
2803 | the SIGTRAP associated with the last time we were | |
2804 | single-stepping LWP A. */ | |
2805 | ||
2806 | /* Resume the thread. It should halt immediately returning the | |
2807 | pending SIGSTOP. */ | |
2808 | registers_changed (); | |
10d6c8cd DJ |
2809 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2810 | lp->step, TARGET_SIGNAL_0); | |
d6b0e80f AC |
2811 | if (debug_linux_nat) |
2812 | fprintf_unfiltered (gdb_stdlog, | |
2813 | "LLW: %s %s, 0, 0 (expect SIGSTOP)\n", | |
2814 | lp->step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2815 | target_pid_to_str (lp->ptid)); | |
2816 | lp->stopped = 0; | |
2817 | gdb_assert (lp->resumed); | |
2818 | ||
2819 | /* This should catch the pending SIGSTOP. */ | |
2820 | stop_wait_callback (lp, NULL); | |
2821 | } | |
2822 | ||
b84876c2 PA |
2823 | if (!target_can_async_p ()) |
2824 | { | |
2825 | /* Causes SIGINT to be passed on to the attached process. */ | |
2826 | set_sigint_trap (); | |
2827 | set_sigio_trap (); | |
2828 | } | |
d6b0e80f AC |
2829 | |
2830 | while (status == 0) | |
2831 | { | |
2832 | pid_t lwpid; | |
2833 | ||
b84876c2 PA |
2834 | if (target_can_async_p ()) |
2835 | /* In async mode, don't ever block. Only look at the locally | |
2836 | queued events. */ | |
2837 | lwpid = queued_waitpid (pid, &status, options); | |
2838 | else | |
2839 | lwpid = my_waitpid (pid, &status, options); | |
2840 | ||
d6b0e80f AC |
2841 | if (lwpid > 0) |
2842 | { | |
2843 | gdb_assert (pid == -1 || lwpid == pid); | |
2844 | ||
2845 | if (debug_linux_nat) | |
2846 | { | |
2847 | fprintf_unfiltered (gdb_stdlog, | |
2848 | "LLW: waitpid %ld received %s\n", | |
2849 | (long) lwpid, status_to_str (status)); | |
2850 | } | |
2851 | ||
02f3fc28 | 2852 | lp = linux_nat_filter_event (lwpid, status, options); |
d6b0e80f AC |
2853 | if (!lp) |
2854 | { | |
02f3fc28 | 2855 | /* A discarded event. */ |
d6b0e80f AC |
2856 | status = 0; |
2857 | continue; | |
2858 | } | |
2859 | ||
2860 | break; | |
2861 | } | |
2862 | ||
2863 | if (pid == -1) | |
2864 | { | |
2865 | /* Alternate between checking cloned and uncloned processes. */ | |
2866 | options ^= __WCLONE; | |
2867 | ||
b84876c2 PA |
2868 | /* And every time we have checked both: |
2869 | In async mode, return to event loop; | |
2870 | In sync mode, suspend waiting for a SIGCHLD signal. */ | |
d6b0e80f | 2871 | if (options & __WCLONE) |
b84876c2 PA |
2872 | { |
2873 | if (target_can_async_p ()) | |
2874 | { | |
2875 | /* No interesting event. */ | |
2876 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
2877 | ||
2878 | /* Get ready for the next event. */ | |
2879 | target_async (inferior_event_handler, 0); | |
2880 | ||
2881 | if (debug_linux_nat_async) | |
2882 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); | |
2883 | ||
2884 | return minus_one_ptid; | |
2885 | } | |
2886 | ||
2887 | sigsuspend (&suspend_mask); | |
2888 | } | |
d6b0e80f AC |
2889 | } |
2890 | ||
2891 | /* We shouldn't end up here unless we want to try again. */ | |
2892 | gdb_assert (status == 0); | |
2893 | } | |
2894 | ||
b84876c2 PA |
2895 | if (!target_can_async_p ()) |
2896 | { | |
2897 | clear_sigio_trap (); | |
2898 | clear_sigint_trap (); | |
2899 | } | |
d6b0e80f AC |
2900 | |
2901 | gdb_assert (lp); | |
2902 | ||
2903 | /* Don't report signals that GDB isn't interested in, such as | |
2904 | signals that are neither printed nor stopped upon. Stopping all | |
2905 | threads can be a bit time-consuming so if we want decent | |
2906 | performance with heavily multi-threaded programs, especially when | |
2907 | they're using a high frequency timer, we'd better avoid it if we | |
2908 | can. */ | |
2909 | ||
2910 | if (WIFSTOPPED (status)) | |
2911 | { | |
2912 | int signo = target_signal_from_host (WSTOPSIG (status)); | |
2913 | ||
d539ed7e UW |
2914 | /* If we get a signal while single-stepping, we may need special |
2915 | care, e.g. to skip the signal handler. Defer to common code. */ | |
2916 | if (!lp->step | |
2917 | && signal_stop_state (signo) == 0 | |
d6b0e80f AC |
2918 | && signal_print_state (signo) == 0 |
2919 | && signal_pass_state (signo) == 1) | |
2920 | { | |
2921 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
2922 | here? It is not clear we should. GDB may not expect | |
2923 | other threads to run. On the other hand, not resuming | |
2924 | newly attached threads may cause an unwanted delay in | |
2925 | getting them running. */ | |
2926 | registers_changed (); | |
10d6c8cd DJ |
2927 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2928 | lp->step, signo); | |
d6b0e80f AC |
2929 | if (debug_linux_nat) |
2930 | fprintf_unfiltered (gdb_stdlog, | |
2931 | "LLW: %s %s, %s (preempt 'handle')\n", | |
2932 | lp->step ? | |
2933 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2934 | target_pid_to_str (lp->ptid), | |
2935 | signo ? strsignal (signo) : "0"); | |
2936 | lp->stopped = 0; | |
2937 | status = 0; | |
2938 | goto retry; | |
2939 | } | |
2940 | ||
2941 | if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0) | |
2942 | { | |
2943 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
57380f4e DJ |
2944 | forwarded to the entire process group, that is, all LWPs |
2945 | will receive it - unless they're using CLONE_THREAD to | |
2946 | share signals. Since we only want to report it once, we | |
2947 | mark it as ignored for all LWPs except this one. */ | |
2948 | iterate_over_lwps (set_ignore_sigint, NULL); | |
2949 | lp->ignore_sigint = 0; | |
d6b0e80f | 2950 | } |
57380f4e DJ |
2951 | else |
2952 | maybe_clear_ignore_sigint (lp); | |
d6b0e80f AC |
2953 | } |
2954 | ||
2955 | /* This LWP is stopped now. */ | |
2956 | lp->stopped = 1; | |
2957 | ||
2958 | if (debug_linux_nat) | |
2959 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
2960 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
2961 | ||
4c28f408 PA |
2962 | if (!non_stop) |
2963 | { | |
2964 | /* Now stop all other LWP's ... */ | |
2965 | iterate_over_lwps (stop_callback, NULL); | |
2966 | ||
2967 | /* ... and wait until all of them have reported back that | |
2968 | they're no longer running. */ | |
57380f4e | 2969 | iterate_over_lwps (stop_wait_callback, NULL); |
4c28f408 PA |
2970 | |
2971 | /* If we're not waiting for a specific LWP, choose an event LWP | |
2972 | from among those that have had events. Giving equal priority | |
2973 | to all LWPs that have had events helps prevent | |
2974 | starvation. */ | |
2975 | if (pid == -1) | |
2976 | select_event_lwp (&lp, &status); | |
2977 | } | |
d6b0e80f AC |
2978 | |
2979 | /* Now that we've selected our final event LWP, cancel any | |
2980 | breakpoints in other LWPs that have hit a GDB breakpoint. See | |
2981 | the comment in cancel_breakpoints_callback to find out why. */ | |
2982 | iterate_over_lwps (cancel_breakpoints_callback, lp); | |
2983 | ||
d6b0e80f AC |
2984 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) |
2985 | { | |
d6b0e80f AC |
2986 | if (debug_linux_nat) |
2987 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
2988 | "LLW: trap ptid is %s.\n", |
2989 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 2990 | } |
d6b0e80f AC |
2991 | |
2992 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2993 | { | |
2994 | *ourstatus = lp->waitstatus; | |
2995 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
2996 | } | |
2997 | else | |
2998 | store_waitstatus (ourstatus, status); | |
2999 | ||
b84876c2 PA |
3000 | /* Get ready for the next event. */ |
3001 | if (target_can_async_p ()) | |
3002 | target_async (inferior_event_handler, 0); | |
3003 | ||
3004 | if (debug_linux_nat_async) | |
3005 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); | |
3006 | ||
f973ed9c | 3007 | return lp->ptid; |
d6b0e80f AC |
3008 | } |
3009 | ||
3010 | static int | |
3011 | kill_callback (struct lwp_info *lp, void *data) | |
3012 | { | |
3013 | errno = 0; | |
3014 | ptrace (PTRACE_KILL, GET_LWP (lp->ptid), 0, 0); | |
3015 | if (debug_linux_nat) | |
3016 | fprintf_unfiltered (gdb_stdlog, | |
3017 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
3018 | target_pid_to_str (lp->ptid), | |
3019 | errno ? safe_strerror (errno) : "OK"); | |
3020 | ||
3021 | return 0; | |
3022 | } | |
3023 | ||
3024 | static int | |
3025 | kill_wait_callback (struct lwp_info *lp, void *data) | |
3026 | { | |
3027 | pid_t pid; | |
3028 | ||
3029 | /* We must make sure that there are no pending events (delayed | |
3030 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3031 | program doesn't interfere with any following debugging session. */ | |
3032 | ||
3033 | /* For cloned processes we must check both with __WCLONE and | |
3034 | without, since the exit status of a cloned process isn't reported | |
3035 | with __WCLONE. */ | |
3036 | if (lp->cloned) | |
3037 | { | |
3038 | do | |
3039 | { | |
58aecb61 | 3040 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE); |
e85a822c | 3041 | if (pid != (pid_t) -1) |
d6b0e80f | 3042 | { |
e85a822c DJ |
3043 | if (debug_linux_nat) |
3044 | fprintf_unfiltered (gdb_stdlog, | |
3045 | "KWC: wait %s received unknown.\n", | |
3046 | target_pid_to_str (lp->ptid)); | |
3047 | /* The Linux kernel sometimes fails to kill a thread | |
3048 | completely after PTRACE_KILL; that goes from the stop | |
3049 | point in do_fork out to the one in | |
3050 | get_signal_to_deliever and waits again. So kill it | |
3051 | again. */ | |
3052 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3053 | } |
3054 | } | |
3055 | while (pid == GET_LWP (lp->ptid)); | |
3056 | ||
3057 | gdb_assert (pid == -1 && errno == ECHILD); | |
3058 | } | |
3059 | ||
3060 | do | |
3061 | { | |
58aecb61 | 3062 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0); |
e85a822c | 3063 | if (pid != (pid_t) -1) |
d6b0e80f | 3064 | { |
e85a822c DJ |
3065 | if (debug_linux_nat) |
3066 | fprintf_unfiltered (gdb_stdlog, | |
3067 | "KWC: wait %s received unk.\n", | |
3068 | target_pid_to_str (lp->ptid)); | |
3069 | /* See the call to kill_callback above. */ | |
3070 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3071 | } |
3072 | } | |
3073 | while (pid == GET_LWP (lp->ptid)); | |
3074 | ||
3075 | gdb_assert (pid == -1 && errno == ECHILD); | |
3076 | return 0; | |
3077 | } | |
3078 | ||
3079 | static void | |
3080 | linux_nat_kill (void) | |
3081 | { | |
f973ed9c DJ |
3082 | struct target_waitstatus last; |
3083 | ptid_t last_ptid; | |
3084 | int status; | |
d6b0e80f | 3085 | |
b84876c2 PA |
3086 | if (target_can_async_p ()) |
3087 | target_async (NULL, 0); | |
3088 | ||
f973ed9c DJ |
3089 | /* If we're stopped while forking and we haven't followed yet, |
3090 | kill the other task. We need to do this first because the | |
3091 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3092 | |
f973ed9c | 3093 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3094 | |
f973ed9c DJ |
3095 | if (last.kind == TARGET_WAITKIND_FORKED |
3096 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3097 | { | |
3a3e9ee3 | 3098 | ptrace (PT_KILL, PIDGET (last.value.related_pid), 0, 0); |
f973ed9c DJ |
3099 | wait (&status); |
3100 | } | |
3101 | ||
3102 | if (forks_exist_p ()) | |
b84876c2 PA |
3103 | { |
3104 | linux_fork_killall (); | |
3105 | drain_queued_events (-1); | |
3106 | } | |
f973ed9c DJ |
3107 | else |
3108 | { | |
4c28f408 PA |
3109 | /* Stop all threads before killing them, since ptrace requires |
3110 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
3111 | iterate_over_lwps (stop_callback, NULL); | |
3112 | /* ... and wait until all of them have reported back that | |
3113 | they're no longer running. */ | |
3114 | iterate_over_lwps (stop_wait_callback, NULL); | |
3115 | ||
f973ed9c DJ |
3116 | /* Kill all LWP's ... */ |
3117 | iterate_over_lwps (kill_callback, NULL); | |
3118 | ||
3119 | /* ... and wait until we've flushed all events. */ | |
3120 | iterate_over_lwps (kill_wait_callback, NULL); | |
3121 | } | |
3122 | ||
3123 | target_mourn_inferior (); | |
d6b0e80f AC |
3124 | } |
3125 | ||
3126 | static void | |
3127 | linux_nat_mourn_inferior (void) | |
3128 | { | |
d6b0e80f AC |
3129 | /* Destroy LWP info; it's no longer valid. */ |
3130 | init_lwp_list (); | |
3131 | ||
f973ed9c | 3132 | if (! forks_exist_p ()) |
b84876c2 PA |
3133 | { |
3134 | /* Normal case, no other forks available. */ | |
3135 | if (target_can_async_p ()) | |
3136 | linux_nat_async (NULL, 0); | |
3137 | linux_ops->to_mourn_inferior (); | |
3138 | } | |
f973ed9c DJ |
3139 | else |
3140 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3141 | there are other viable forks to debug. Delete the exiting | |
3142 | one and context-switch to the first available. */ | |
3143 | linux_fork_mourn_inferior (); | |
d6b0e80f AC |
3144 | } |
3145 | ||
10d6c8cd DJ |
3146 | static LONGEST |
3147 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, | |
3148 | const char *annex, gdb_byte *readbuf, | |
3149 | const gdb_byte *writebuf, | |
3150 | ULONGEST offset, LONGEST len) | |
d6b0e80f AC |
3151 | { |
3152 | struct cleanup *old_chain = save_inferior_ptid (); | |
10d6c8cd | 3153 | LONGEST xfer; |
d6b0e80f AC |
3154 | |
3155 | if (is_lwp (inferior_ptid)) | |
3156 | inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid)); | |
3157 | ||
10d6c8cd DJ |
3158 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
3159 | offset, len); | |
d6b0e80f AC |
3160 | |
3161 | do_cleanups (old_chain); | |
3162 | return xfer; | |
3163 | } | |
3164 | ||
3165 | static int | |
3166 | linux_nat_thread_alive (ptid_t ptid) | |
3167 | { | |
4c28f408 PA |
3168 | int err; |
3169 | ||
d6b0e80f AC |
3170 | gdb_assert (is_lwp (ptid)); |
3171 | ||
4c28f408 PA |
3172 | /* Send signal 0 instead of anything ptrace, because ptracing a |
3173 | running thread errors out claiming that the thread doesn't | |
3174 | exist. */ | |
3175 | err = kill_lwp (GET_LWP (ptid), 0); | |
3176 | ||
d6b0e80f AC |
3177 | if (debug_linux_nat) |
3178 | fprintf_unfiltered (gdb_stdlog, | |
4c28f408 | 3179 | "LLTA: KILL(SIG0) %s (%s)\n", |
d6b0e80f | 3180 | target_pid_to_str (ptid), |
4c28f408 | 3181 | err ? safe_strerror (err) : "OK"); |
9c0dd46b | 3182 | |
4c28f408 | 3183 | if (err != 0) |
d6b0e80f AC |
3184 | return 0; |
3185 | ||
3186 | return 1; | |
3187 | } | |
3188 | ||
3189 | static char * | |
3190 | linux_nat_pid_to_str (ptid_t ptid) | |
3191 | { | |
3192 | static char buf[64]; | |
3193 | ||
a0ef4274 DJ |
3194 | if (is_lwp (ptid) |
3195 | && ((lwp_list && lwp_list->next) | |
3196 | || GET_PID (ptid) != GET_LWP (ptid))) | |
d6b0e80f AC |
3197 | { |
3198 | snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid)); | |
3199 | return buf; | |
3200 | } | |
3201 | ||
3202 | return normal_pid_to_str (ptid); | |
3203 | } | |
3204 | ||
d6b0e80f AC |
3205 | static void |
3206 | sigchld_handler (int signo) | |
3207 | { | |
b84876c2 | 3208 | if (linux_nat_async_enabled |
84e46146 | 3209 | && linux_nat_async_events_state != sigchld_sync |
b84876c2 PA |
3210 | && signo == SIGCHLD) |
3211 | /* It is *always* a bug to hit this. */ | |
3212 | internal_error (__FILE__, __LINE__, | |
3213 | "sigchld_handler called when async events are enabled"); | |
3214 | ||
d6b0e80f AC |
3215 | /* Do nothing. The only reason for this handler is that it allows |
3216 | us to use sigsuspend in linux_nat_wait above to wait for the | |
3217 | arrival of a SIGCHLD. */ | |
3218 | } | |
3219 | ||
dba24537 AC |
3220 | /* Accepts an integer PID; Returns a string representing a file that |
3221 | can be opened to get the symbols for the child process. */ | |
3222 | ||
6d8fd2b7 UW |
3223 | static char * |
3224 | linux_child_pid_to_exec_file (int pid) | |
dba24537 AC |
3225 | { |
3226 | char *name1, *name2; | |
3227 | ||
3228 | name1 = xmalloc (MAXPATHLEN); | |
3229 | name2 = xmalloc (MAXPATHLEN); | |
3230 | make_cleanup (xfree, name1); | |
3231 | make_cleanup (xfree, name2); | |
3232 | memset (name2, 0, MAXPATHLEN); | |
3233 | ||
3234 | sprintf (name1, "/proc/%d/exe", pid); | |
3235 | if (readlink (name1, name2, MAXPATHLEN) > 0) | |
3236 | return name2; | |
3237 | else | |
3238 | return name1; | |
3239 | } | |
3240 | ||
3241 | /* Service function for corefiles and info proc. */ | |
3242 | ||
3243 | static int | |
3244 | read_mapping (FILE *mapfile, | |
3245 | long long *addr, | |
3246 | long long *endaddr, | |
3247 | char *permissions, | |
3248 | long long *offset, | |
3249 | char *device, long long *inode, char *filename) | |
3250 | { | |
3251 | int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx", | |
3252 | addr, endaddr, permissions, offset, device, inode); | |
3253 | ||
2e14c2ea MS |
3254 | filename[0] = '\0'; |
3255 | if (ret > 0 && ret != EOF) | |
dba24537 AC |
3256 | { |
3257 | /* Eat everything up to EOL for the filename. This will prevent | |
3258 | weird filenames (such as one with embedded whitespace) from | |
3259 | confusing this code. It also makes this code more robust in | |
3260 | respect to annotations the kernel may add after the filename. | |
3261 | ||
3262 | Note the filename is used for informational purposes | |
3263 | only. */ | |
3264 | ret += fscanf (mapfile, "%[^\n]\n", filename); | |
3265 | } | |
2e14c2ea | 3266 | |
dba24537 AC |
3267 | return (ret != 0 && ret != EOF); |
3268 | } | |
3269 | ||
3270 | /* Fills the "to_find_memory_regions" target vector. Lists the memory | |
3271 | regions in the inferior for a corefile. */ | |
3272 | ||
3273 | static int | |
3274 | linux_nat_find_memory_regions (int (*func) (CORE_ADDR, | |
3275 | unsigned long, | |
3276 | int, int, int, void *), void *obfd) | |
3277 | { | |
3278 | long long pid = PIDGET (inferior_ptid); | |
3279 | char mapsfilename[MAXPATHLEN]; | |
3280 | FILE *mapsfile; | |
3281 | long long addr, endaddr, size, offset, inode; | |
3282 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3283 | int read, write, exec; | |
3284 | int ret; | |
3285 | ||
3286 | /* Compose the filename for the /proc memory map, and open it. */ | |
3287 | sprintf (mapsfilename, "/proc/%lld/maps", pid); | |
3288 | if ((mapsfile = fopen (mapsfilename, "r")) == NULL) | |
8a3fe4f8 | 3289 | error (_("Could not open %s."), mapsfilename); |
dba24537 AC |
3290 | |
3291 | if (info_verbose) | |
3292 | fprintf_filtered (gdb_stdout, | |
3293 | "Reading memory regions from %s\n", mapsfilename); | |
3294 | ||
3295 | /* Now iterate until end-of-file. */ | |
3296 | while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0], | |
3297 | &offset, &device[0], &inode, &filename[0])) | |
3298 | { | |
3299 | size = endaddr - addr; | |
3300 | ||
3301 | /* Get the segment's permissions. */ | |
3302 | read = (strchr (permissions, 'r') != 0); | |
3303 | write = (strchr (permissions, 'w') != 0); | |
3304 | exec = (strchr (permissions, 'x') != 0); | |
3305 | ||
3306 | if (info_verbose) | |
3307 | { | |
3308 | fprintf_filtered (gdb_stdout, | |
3309 | "Save segment, %lld bytes at 0x%s (%c%c%c)", | |
3310 | size, paddr_nz (addr), | |
3311 | read ? 'r' : ' ', | |
3312 | write ? 'w' : ' ', exec ? 'x' : ' '); | |
b260b6c1 | 3313 | if (filename[0]) |
dba24537 AC |
3314 | fprintf_filtered (gdb_stdout, " for %s", filename); |
3315 | fprintf_filtered (gdb_stdout, "\n"); | |
3316 | } | |
3317 | ||
3318 | /* Invoke the callback function to create the corefile | |
3319 | segment. */ | |
3320 | func (addr, size, read, write, exec, obfd); | |
3321 | } | |
3322 | fclose (mapsfile); | |
3323 | return 0; | |
3324 | } | |
3325 | ||
3326 | /* Records the thread's register state for the corefile note | |
3327 | section. */ | |
3328 | ||
3329 | static char * | |
3330 | linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid, | |
3331 | char *note_data, int *note_size) | |
3332 | { | |
3333 | gdb_gregset_t gregs; | |
3334 | gdb_fpregset_t fpregs; | |
dba24537 | 3335 | unsigned long lwp = ptid_get_lwp (ptid); |
594f7785 UW |
3336 | struct regcache *regcache = get_thread_regcache (ptid); |
3337 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
4f844a66 | 3338 | const struct regset *regset; |
55e969c1 | 3339 | int core_regset_p; |
594f7785 | 3340 | struct cleanup *old_chain; |
17ea7499 CES |
3341 | struct core_regset_section *sect_list; |
3342 | char *gdb_regset; | |
594f7785 UW |
3343 | |
3344 | old_chain = save_inferior_ptid (); | |
3345 | inferior_ptid = ptid; | |
3346 | target_fetch_registers (regcache, -1); | |
3347 | do_cleanups (old_chain); | |
4f844a66 DM |
3348 | |
3349 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
17ea7499 CES |
3350 | sect_list = gdbarch_core_regset_sections (gdbarch); |
3351 | ||
55e969c1 DM |
3352 | if (core_regset_p |
3353 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
3354 | sizeof (gregs))) != NULL | |
3355 | && regset->collect_regset != NULL) | |
594f7785 | 3356 | regset->collect_regset (regset, regcache, -1, |
55e969c1 | 3357 | &gregs, sizeof (gregs)); |
4f844a66 | 3358 | else |
594f7785 | 3359 | fill_gregset (regcache, &gregs, -1); |
4f844a66 | 3360 | |
55e969c1 DM |
3361 | note_data = (char *) elfcore_write_prstatus (obfd, |
3362 | note_data, | |
3363 | note_size, | |
3364 | lwp, | |
3365 | stop_signal, &gregs); | |
3366 | ||
17ea7499 CES |
3367 | /* The loop below uses the new struct core_regset_section, which stores |
3368 | the supported section names and sizes for the core file. Note that | |
3369 | note PRSTATUS needs to be treated specially. But the other notes are | |
3370 | structurally the same, so they can benefit from the new struct. */ | |
3371 | if (core_regset_p && sect_list != NULL) | |
3372 | while (sect_list->sect_name != NULL) | |
3373 | { | |
3374 | /* .reg was already handled above. */ | |
3375 | if (strcmp (sect_list->sect_name, ".reg") == 0) | |
3376 | { | |
3377 | sect_list++; | |
3378 | continue; | |
3379 | } | |
3380 | regset = gdbarch_regset_from_core_section (gdbarch, | |
3381 | sect_list->sect_name, | |
3382 | sect_list->size); | |
3383 | gdb_assert (regset && regset->collect_regset); | |
3384 | gdb_regset = xmalloc (sect_list->size); | |
3385 | regset->collect_regset (regset, regcache, -1, | |
3386 | gdb_regset, sect_list->size); | |
3387 | note_data = (char *) elfcore_write_register_note (obfd, | |
3388 | note_data, | |
3389 | note_size, | |
3390 | sect_list->sect_name, | |
3391 | gdb_regset, | |
3392 | sect_list->size); | |
3393 | xfree (gdb_regset); | |
3394 | sect_list++; | |
3395 | } | |
dba24537 | 3396 | |
17ea7499 CES |
3397 | /* For architectures that does not have the struct core_regset_section |
3398 | implemented, we use the old method. When all the architectures have | |
3399 | the new support, the code below should be deleted. */ | |
4f844a66 | 3400 | else |
17ea7499 CES |
3401 | { |
3402 | if (core_regset_p | |
3403 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
3404 | sizeof (fpregs))) != NULL | |
3405 | && regset->collect_regset != NULL) | |
3406 | regset->collect_regset (regset, regcache, -1, | |
3407 | &fpregs, sizeof (fpregs)); | |
3408 | else | |
3409 | fill_fpregset (regcache, &fpregs, -1); | |
3410 | ||
3411 | note_data = (char *) elfcore_write_prfpreg (obfd, | |
3412 | note_data, | |
3413 | note_size, | |
3414 | &fpregs, sizeof (fpregs)); | |
3415 | } | |
4f844a66 | 3416 | |
dba24537 AC |
3417 | return note_data; |
3418 | } | |
3419 | ||
3420 | struct linux_nat_corefile_thread_data | |
3421 | { | |
3422 | bfd *obfd; | |
3423 | char *note_data; | |
3424 | int *note_size; | |
3425 | int num_notes; | |
3426 | }; | |
3427 | ||
3428 | /* Called by gdbthread.c once per thread. Records the thread's | |
3429 | register state for the corefile note section. */ | |
3430 | ||
3431 | static int | |
3432 | linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data) | |
3433 | { | |
3434 | struct linux_nat_corefile_thread_data *args = data; | |
dba24537 | 3435 | |
dba24537 AC |
3436 | args->note_data = linux_nat_do_thread_registers (args->obfd, |
3437 | ti->ptid, | |
3438 | args->note_data, | |
3439 | args->note_size); | |
3440 | args->num_notes++; | |
56be3814 | 3441 | |
dba24537 AC |
3442 | return 0; |
3443 | } | |
3444 | ||
3445 | /* Records the register state for the corefile note section. */ | |
3446 | ||
3447 | static char * | |
3448 | linux_nat_do_registers (bfd *obfd, ptid_t ptid, | |
3449 | char *note_data, int *note_size) | |
3450 | { | |
dba24537 AC |
3451 | return linux_nat_do_thread_registers (obfd, |
3452 | ptid_build (ptid_get_pid (inferior_ptid), | |
3453 | ptid_get_pid (inferior_ptid), | |
3454 | 0), | |
3455 | note_data, note_size); | |
dba24537 AC |
3456 | } |
3457 | ||
3458 | /* Fills the "to_make_corefile_note" target vector. Builds the note | |
3459 | section for a corefile, and returns it in a malloc buffer. */ | |
3460 | ||
3461 | static char * | |
3462 | linux_nat_make_corefile_notes (bfd *obfd, int *note_size) | |
3463 | { | |
3464 | struct linux_nat_corefile_thread_data thread_args; | |
3465 | struct cleanup *old_chain; | |
d99148ef | 3466 | /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */ |
dba24537 | 3467 | char fname[16] = { '\0' }; |
d99148ef | 3468 | /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */ |
dba24537 AC |
3469 | char psargs[80] = { '\0' }; |
3470 | char *note_data = NULL; | |
3471 | ptid_t current_ptid = inferior_ptid; | |
c6826062 | 3472 | gdb_byte *auxv; |
dba24537 AC |
3473 | int auxv_len; |
3474 | ||
3475 | if (get_exec_file (0)) | |
3476 | { | |
3477 | strncpy (fname, strrchr (get_exec_file (0), '/') + 1, sizeof (fname)); | |
3478 | strncpy (psargs, get_exec_file (0), sizeof (psargs)); | |
3479 | if (get_inferior_args ()) | |
3480 | { | |
d99148ef JK |
3481 | char *string_end; |
3482 | char *psargs_end = psargs + sizeof (psargs); | |
3483 | ||
3484 | /* linux_elfcore_write_prpsinfo () handles zero unterminated | |
3485 | strings fine. */ | |
3486 | string_end = memchr (psargs, 0, sizeof (psargs)); | |
3487 | if (string_end != NULL) | |
3488 | { | |
3489 | *string_end++ = ' '; | |
3490 | strncpy (string_end, get_inferior_args (), | |
3491 | psargs_end - string_end); | |
3492 | } | |
dba24537 AC |
3493 | } |
3494 | note_data = (char *) elfcore_write_prpsinfo (obfd, | |
3495 | note_data, | |
3496 | note_size, fname, psargs); | |
3497 | } | |
3498 | ||
3499 | /* Dump information for threads. */ | |
3500 | thread_args.obfd = obfd; | |
3501 | thread_args.note_data = note_data; | |
3502 | thread_args.note_size = note_size; | |
3503 | thread_args.num_notes = 0; | |
3504 | iterate_over_lwps (linux_nat_corefile_thread_callback, &thread_args); | |
3505 | if (thread_args.num_notes == 0) | |
3506 | { | |
3507 | /* iterate_over_threads didn't come up with any threads; just | |
3508 | use inferior_ptid. */ | |
3509 | note_data = linux_nat_do_registers (obfd, inferior_ptid, | |
3510 | note_data, note_size); | |
3511 | } | |
3512 | else | |
3513 | { | |
3514 | note_data = thread_args.note_data; | |
3515 | } | |
3516 | ||
13547ab6 DJ |
3517 | auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV, |
3518 | NULL, &auxv); | |
dba24537 AC |
3519 | if (auxv_len > 0) |
3520 | { | |
3521 | note_data = elfcore_write_note (obfd, note_data, note_size, | |
3522 | "CORE", NT_AUXV, auxv, auxv_len); | |
3523 | xfree (auxv); | |
3524 | } | |
3525 | ||
3526 | make_cleanup (xfree, note_data); | |
3527 | return note_data; | |
3528 | } | |
3529 | ||
3530 | /* Implement the "info proc" command. */ | |
3531 | ||
3532 | static void | |
3533 | linux_nat_info_proc_cmd (char *args, int from_tty) | |
3534 | { | |
3535 | long long pid = PIDGET (inferior_ptid); | |
3536 | FILE *procfile; | |
3537 | char **argv = NULL; | |
3538 | char buffer[MAXPATHLEN]; | |
3539 | char fname1[MAXPATHLEN], fname2[MAXPATHLEN]; | |
3540 | int cmdline_f = 1; | |
3541 | int cwd_f = 1; | |
3542 | int exe_f = 1; | |
3543 | int mappings_f = 0; | |
3544 | int environ_f = 0; | |
3545 | int status_f = 0; | |
3546 | int stat_f = 0; | |
3547 | int all = 0; | |
3548 | struct stat dummy; | |
3549 | ||
3550 | if (args) | |
3551 | { | |
3552 | /* Break up 'args' into an argv array. */ | |
3553 | if ((argv = buildargv (args)) == NULL) | |
3554 | nomem (0); | |
3555 | else | |
3556 | make_cleanup_freeargv (argv); | |
3557 | } | |
3558 | while (argv != NULL && *argv != NULL) | |
3559 | { | |
3560 | if (isdigit (argv[0][0])) | |
3561 | { | |
3562 | pid = strtoul (argv[0], NULL, 10); | |
3563 | } | |
3564 | else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0) | |
3565 | { | |
3566 | mappings_f = 1; | |
3567 | } | |
3568 | else if (strcmp (argv[0], "status") == 0) | |
3569 | { | |
3570 | status_f = 1; | |
3571 | } | |
3572 | else if (strcmp (argv[0], "stat") == 0) | |
3573 | { | |
3574 | stat_f = 1; | |
3575 | } | |
3576 | else if (strcmp (argv[0], "cmd") == 0) | |
3577 | { | |
3578 | cmdline_f = 1; | |
3579 | } | |
3580 | else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0) | |
3581 | { | |
3582 | exe_f = 1; | |
3583 | } | |
3584 | else if (strcmp (argv[0], "cwd") == 0) | |
3585 | { | |
3586 | cwd_f = 1; | |
3587 | } | |
3588 | else if (strncmp (argv[0], "all", strlen (argv[0])) == 0) | |
3589 | { | |
3590 | all = 1; | |
3591 | } | |
3592 | else | |
3593 | { | |
3594 | /* [...] (future options here) */ | |
3595 | } | |
3596 | argv++; | |
3597 | } | |
3598 | if (pid == 0) | |
8a3fe4f8 | 3599 | error (_("No current process: you must name one.")); |
dba24537 AC |
3600 | |
3601 | sprintf (fname1, "/proc/%lld", pid); | |
3602 | if (stat (fname1, &dummy) != 0) | |
8a3fe4f8 | 3603 | error (_("No /proc directory: '%s'"), fname1); |
dba24537 | 3604 | |
a3f17187 | 3605 | printf_filtered (_("process %lld\n"), pid); |
dba24537 AC |
3606 | if (cmdline_f || all) |
3607 | { | |
3608 | sprintf (fname1, "/proc/%lld/cmdline", pid); | |
d5d6fca5 | 3609 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3610 | { |
3611 | fgets (buffer, sizeof (buffer), procfile); | |
3612 | printf_filtered ("cmdline = '%s'\n", buffer); | |
3613 | fclose (procfile); | |
3614 | } | |
3615 | else | |
8a3fe4f8 | 3616 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3617 | } |
3618 | if (cwd_f || all) | |
3619 | { | |
3620 | sprintf (fname1, "/proc/%lld/cwd", pid); | |
3621 | memset (fname2, 0, sizeof (fname2)); | |
3622 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3623 | printf_filtered ("cwd = '%s'\n", fname2); | |
3624 | else | |
8a3fe4f8 | 3625 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3626 | } |
3627 | if (exe_f || all) | |
3628 | { | |
3629 | sprintf (fname1, "/proc/%lld/exe", pid); | |
3630 | memset (fname2, 0, sizeof (fname2)); | |
3631 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3632 | printf_filtered ("exe = '%s'\n", fname2); | |
3633 | else | |
8a3fe4f8 | 3634 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3635 | } |
3636 | if (mappings_f || all) | |
3637 | { | |
3638 | sprintf (fname1, "/proc/%lld/maps", pid); | |
d5d6fca5 | 3639 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3640 | { |
3641 | long long addr, endaddr, size, offset, inode; | |
3642 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3643 | ||
a3f17187 | 3644 | printf_filtered (_("Mapped address spaces:\n\n")); |
17a912b6 | 3645 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3646 | { |
3647 | printf_filtered ("\t%10s %10s %10s %10s %7s\n", | |
3648 | "Start Addr", | |
3649 | " End Addr", | |
3650 | " Size", " Offset", "objfile"); | |
3651 | } | |
3652 | else | |
3653 | { | |
3654 | printf_filtered (" %18s %18s %10s %10s %7s\n", | |
3655 | "Start Addr", | |
3656 | " End Addr", | |
3657 | " Size", " Offset", "objfile"); | |
3658 | } | |
3659 | ||
3660 | while (read_mapping (procfile, &addr, &endaddr, &permissions[0], | |
3661 | &offset, &device[0], &inode, &filename[0])) | |
3662 | { | |
3663 | size = endaddr - addr; | |
3664 | ||
3665 | /* FIXME: carlton/2003-08-27: Maybe the printf_filtered | |
3666 | calls here (and possibly above) should be abstracted | |
3667 | out into their own functions? Andrew suggests using | |
3668 | a generic local_address_string instead to print out | |
3669 | the addresses; that makes sense to me, too. */ | |
3670 | ||
17a912b6 | 3671 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3672 | { |
3673 | printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n", | |
3674 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3675 | (unsigned long) endaddr, | |
3676 | (int) size, | |
3677 | (unsigned int) offset, | |
3678 | filename[0] ? filename : ""); | |
3679 | } | |
3680 | else | |
3681 | { | |
3682 | printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n", | |
3683 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3684 | (unsigned long) endaddr, | |
3685 | (int) size, | |
3686 | (unsigned int) offset, | |
3687 | filename[0] ? filename : ""); | |
3688 | } | |
3689 | } | |
3690 | ||
3691 | fclose (procfile); | |
3692 | } | |
3693 | else | |
8a3fe4f8 | 3694 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3695 | } |
3696 | if (status_f || all) | |
3697 | { | |
3698 | sprintf (fname1, "/proc/%lld/status", pid); | |
d5d6fca5 | 3699 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3700 | { |
3701 | while (fgets (buffer, sizeof (buffer), procfile) != NULL) | |
3702 | puts_filtered (buffer); | |
3703 | fclose (procfile); | |
3704 | } | |
3705 | else | |
8a3fe4f8 | 3706 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3707 | } |
3708 | if (stat_f || all) | |
3709 | { | |
3710 | sprintf (fname1, "/proc/%lld/stat", pid); | |
d5d6fca5 | 3711 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3712 | { |
3713 | int itmp; | |
3714 | char ctmp; | |
a25694b4 | 3715 | long ltmp; |
dba24537 AC |
3716 | |
3717 | if (fscanf (procfile, "%d ", &itmp) > 0) | |
a3f17187 | 3718 | printf_filtered (_("Process: %d\n"), itmp); |
a25694b4 | 3719 | if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0) |
a3f17187 | 3720 | printf_filtered (_("Exec file: %s\n"), buffer); |
dba24537 | 3721 | if (fscanf (procfile, "%c ", &ctmp) > 0) |
a3f17187 | 3722 | printf_filtered (_("State: %c\n"), ctmp); |
dba24537 | 3723 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3724 | printf_filtered (_("Parent process: %d\n"), itmp); |
dba24537 | 3725 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3726 | printf_filtered (_("Process group: %d\n"), itmp); |
dba24537 | 3727 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3728 | printf_filtered (_("Session id: %d\n"), itmp); |
dba24537 | 3729 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3730 | printf_filtered (_("TTY: %d\n"), itmp); |
dba24537 | 3731 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3732 | printf_filtered (_("TTY owner process group: %d\n"), itmp); |
a25694b4 AS |
3733 | if (fscanf (procfile, "%lu ", <mp) > 0) |
3734 | printf_filtered (_("Flags: 0x%lx\n"), ltmp); | |
3735 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3736 | printf_filtered (_("Minor faults (no memory page): %lu\n"), | |
3737 | (unsigned long) ltmp); | |
3738 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3739 | printf_filtered (_("Minor faults, children: %lu\n"), | |
3740 | (unsigned long) ltmp); | |
3741 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3742 | printf_filtered (_("Major faults (memory page faults): %lu\n"), | |
3743 | (unsigned long) ltmp); | |
3744 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3745 | printf_filtered (_("Major faults, children: %lu\n"), | |
3746 | (unsigned long) ltmp); | |
3747 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3748 | printf_filtered (_("utime: %ld\n"), ltmp); | |
3749 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3750 | printf_filtered (_("stime: %ld\n"), ltmp); | |
3751 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3752 | printf_filtered (_("utime, children: %ld\n"), ltmp); | |
3753 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3754 | printf_filtered (_("stime, children: %ld\n"), ltmp); | |
3755 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3756 | printf_filtered (_("jiffies remaining in current time slice: %ld\n"), | |
3757 | ltmp); | |
3758 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3759 | printf_filtered (_("'nice' value: %ld\n"), ltmp); | |
3760 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3761 | printf_filtered (_("jiffies until next timeout: %lu\n"), | |
3762 | (unsigned long) ltmp); | |
3763 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3764 | printf_filtered (_("jiffies until next SIGALRM: %lu\n"), | |
3765 | (unsigned long) ltmp); | |
3766 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3767 | printf_filtered (_("start time (jiffies since system boot): %ld\n"), | |
3768 | ltmp); | |
3769 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3770 | printf_filtered (_("Virtual memory size: %lu\n"), | |
3771 | (unsigned long) ltmp); | |
3772 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3773 | printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp); | |
3774 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3775 | printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp); | |
3776 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3777 | printf_filtered (_("Start of text: 0x%lx\n"), ltmp); | |
3778 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3779 | printf_filtered (_("End of text: 0x%lx\n"), ltmp); | |
3780 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3781 | printf_filtered (_("Start of stack: 0x%lx\n"), ltmp); | |
dba24537 AC |
3782 | #if 0 /* Don't know how architecture-dependent the rest is... |
3783 | Anyway the signal bitmap info is available from "status". */ | |
a25694b4 AS |
3784 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ |
3785 | printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp); | |
3786 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3787 | printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp); | |
3788 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3789 | printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp); | |
3790 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3791 | printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp); | |
3792 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3793 | printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp); | |
3794 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3795 | printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp); | |
3796 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3797 | printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp); | |
dba24537 AC |
3798 | #endif |
3799 | fclose (procfile); | |
3800 | } | |
3801 | else | |
8a3fe4f8 | 3802 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3803 | } |
3804 | } | |
3805 | ||
10d6c8cd DJ |
3806 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
3807 | filesystem. Because we can use a single read() call for /proc, this | |
3808 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
3809 | but it doesn't support writes. */ | |
3810 | ||
3811 | static LONGEST | |
3812 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, | |
3813 | const char *annex, gdb_byte *readbuf, | |
3814 | const gdb_byte *writebuf, | |
3815 | ULONGEST offset, LONGEST len) | |
dba24537 | 3816 | { |
10d6c8cd DJ |
3817 | LONGEST ret; |
3818 | int fd; | |
dba24537 AC |
3819 | char filename[64]; |
3820 | ||
10d6c8cd | 3821 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
3822 | return 0; |
3823 | ||
3824 | /* Don't bother for one word. */ | |
3825 | if (len < 3 * sizeof (long)) | |
3826 | return 0; | |
3827 | ||
3828 | /* We could keep this file open and cache it - possibly one per | |
3829 | thread. That requires some juggling, but is even faster. */ | |
3830 | sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid)); | |
3831 | fd = open (filename, O_RDONLY | O_LARGEFILE); | |
3832 | if (fd == -1) | |
3833 | return 0; | |
3834 | ||
3835 | /* If pread64 is available, use it. It's faster if the kernel | |
3836 | supports it (only one syscall), and it's 64-bit safe even on | |
3837 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
3838 | application). */ | |
3839 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 3840 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 3841 | #else |
10d6c8cd | 3842 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
3843 | #endif |
3844 | ret = 0; | |
3845 | else | |
3846 | ret = len; | |
3847 | ||
3848 | close (fd); | |
3849 | return ret; | |
3850 | } | |
3851 | ||
3852 | /* Parse LINE as a signal set and add its set bits to SIGS. */ | |
3853 | ||
3854 | static void | |
3855 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
3856 | { | |
3857 | int len = strlen (line) - 1; | |
3858 | const char *p; | |
3859 | int signum; | |
3860 | ||
3861 | if (line[len] != '\n') | |
8a3fe4f8 | 3862 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3863 | |
3864 | p = line; | |
3865 | signum = len * 4; | |
3866 | while (len-- > 0) | |
3867 | { | |
3868 | int digit; | |
3869 | ||
3870 | if (*p >= '0' && *p <= '9') | |
3871 | digit = *p - '0'; | |
3872 | else if (*p >= 'a' && *p <= 'f') | |
3873 | digit = *p - 'a' + 10; | |
3874 | else | |
8a3fe4f8 | 3875 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3876 | |
3877 | signum -= 4; | |
3878 | ||
3879 | if (digit & 1) | |
3880 | sigaddset (sigs, signum + 1); | |
3881 | if (digit & 2) | |
3882 | sigaddset (sigs, signum + 2); | |
3883 | if (digit & 4) | |
3884 | sigaddset (sigs, signum + 3); | |
3885 | if (digit & 8) | |
3886 | sigaddset (sigs, signum + 4); | |
3887 | ||
3888 | p++; | |
3889 | } | |
3890 | } | |
3891 | ||
3892 | /* Find process PID's pending signals from /proc/pid/status and set | |
3893 | SIGS to match. */ | |
3894 | ||
3895 | void | |
3896 | linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigset_t *ignored) | |
3897 | { | |
3898 | FILE *procfile; | |
3899 | char buffer[MAXPATHLEN], fname[MAXPATHLEN]; | |
3900 | int signum; | |
3901 | ||
3902 | sigemptyset (pending); | |
3903 | sigemptyset (blocked); | |
3904 | sigemptyset (ignored); | |
3905 | sprintf (fname, "/proc/%d/status", pid); | |
3906 | procfile = fopen (fname, "r"); | |
3907 | if (procfile == NULL) | |
8a3fe4f8 | 3908 | error (_("Could not open %s"), fname); |
dba24537 AC |
3909 | |
3910 | while (fgets (buffer, MAXPATHLEN, procfile) != NULL) | |
3911 | { | |
3912 | /* Normal queued signals are on the SigPnd line in the status | |
3913 | file. However, 2.6 kernels also have a "shared" pending | |
3914 | queue for delivering signals to a thread group, so check for | |
3915 | a ShdPnd line also. | |
3916 | ||
3917 | Unfortunately some Red Hat kernels include the shared pending | |
3918 | queue but not the ShdPnd status field. */ | |
3919 | ||
3920 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
3921 | add_line_to_sigset (buffer + 8, pending); | |
3922 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
3923 | add_line_to_sigset (buffer + 8, pending); | |
3924 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
3925 | add_line_to_sigset (buffer + 8, blocked); | |
3926 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
3927 | add_line_to_sigset (buffer + 8, ignored); | |
3928 | } | |
3929 | ||
3930 | fclose (procfile); | |
3931 | } | |
3932 | ||
10d6c8cd DJ |
3933 | static LONGEST |
3934 | linux_xfer_partial (struct target_ops *ops, enum target_object object, | |
3935 | const char *annex, gdb_byte *readbuf, | |
3936 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
3937 | { | |
3938 | LONGEST xfer; | |
3939 | ||
3940 | if (object == TARGET_OBJECT_AUXV) | |
3941 | return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf, | |
3942 | offset, len); | |
3943 | ||
3944 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3945 | offset, len); | |
3946 | if (xfer != 0) | |
3947 | return xfer; | |
3948 | ||
3949 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3950 | offset, len); | |
3951 | } | |
3952 | ||
e9efe249 | 3953 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
3954 | it with local methods. */ |
3955 | ||
910122bf UW |
3956 | static void |
3957 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 3958 | { |
6d8fd2b7 UW |
3959 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
3960 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; | |
3961 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; | |
3962 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; | |
10d6c8cd | 3963 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
3964 | t->to_post_attach = linux_child_post_attach; |
3965 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
3966 | t->to_find_memory_regions = linux_nat_find_memory_regions; |
3967 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; | |
3968 | ||
3969 | super_xfer_partial = t->to_xfer_partial; | |
3970 | t->to_xfer_partial = linux_xfer_partial; | |
910122bf UW |
3971 | } |
3972 | ||
3973 | struct target_ops * | |
3974 | linux_target (void) | |
3975 | { | |
3976 | struct target_ops *t; | |
3977 | ||
3978 | t = inf_ptrace_target (); | |
3979 | linux_target_install_ops (t); | |
3980 | ||
3981 | return t; | |
3982 | } | |
3983 | ||
3984 | struct target_ops * | |
7714d83a | 3985 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
3986 | { |
3987 | struct target_ops *t; | |
3988 | ||
3989 | t = inf_ptrace_trad_target (register_u_offset); | |
3990 | linux_target_install_ops (t); | |
10d6c8cd | 3991 | |
10d6c8cd DJ |
3992 | return t; |
3993 | } | |
3994 | ||
b84876c2 PA |
3995 | /* Controls if async mode is permitted. */ |
3996 | static int linux_async_permitted = 0; | |
3997 | ||
3998 | /* The set command writes to this variable. If the inferior is | |
3999 | executing, linux_nat_async_permitted is *not* updated. */ | |
4000 | static int linux_async_permitted_1 = 0; | |
4001 | ||
4002 | static void | |
4003 | set_maintenance_linux_async_permitted (char *args, int from_tty, | |
4004 | struct cmd_list_element *c) | |
4005 | { | |
4006 | if (target_has_execution) | |
4007 | { | |
4008 | linux_async_permitted_1 = linux_async_permitted; | |
4009 | error (_("Cannot change this setting while the inferior is running.")); | |
4010 | } | |
4011 | ||
4012 | linux_async_permitted = linux_async_permitted_1; | |
4013 | linux_nat_set_async_mode (linux_async_permitted); | |
4014 | } | |
4015 | ||
4016 | static void | |
4017 | show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty, | |
4018 | struct cmd_list_element *c, const char *value) | |
4019 | { | |
4020 | fprintf_filtered (file, _("\ | |
4021 | Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"), | |
4022 | value); | |
4023 | } | |
4024 | ||
4025 | /* target_is_async_p implementation. */ | |
4026 | ||
4027 | static int | |
4028 | linux_nat_is_async_p (void) | |
4029 | { | |
4030 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
4031 | it explicitly with the "maintenance set linux-async" command. | |
4032 | Someday, linux will always be async. */ | |
4033 | if (!linux_async_permitted) | |
4034 | return 0; | |
4035 | ||
4036 | return 1; | |
4037 | } | |
4038 | ||
4039 | /* target_can_async_p implementation. */ | |
4040 | ||
4041 | static int | |
4042 | linux_nat_can_async_p (void) | |
4043 | { | |
4044 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
4045 | it explicitly with the "maintenance set linux-async" command. | |
4046 | Someday, linux will always be async. */ | |
4047 | if (!linux_async_permitted) | |
4048 | return 0; | |
4049 | ||
4050 | /* See target.h/target_async_mask. */ | |
4051 | return linux_nat_async_mask_value; | |
4052 | } | |
4053 | ||
4054 | /* target_async_mask implementation. */ | |
4055 | ||
4056 | static int | |
4057 | linux_nat_async_mask (int mask) | |
4058 | { | |
4059 | int current_state; | |
4060 | current_state = linux_nat_async_mask_value; | |
4061 | ||
4062 | if (current_state != mask) | |
4063 | { | |
4064 | if (mask == 0) | |
4065 | { | |
4066 | linux_nat_async (NULL, 0); | |
4067 | linux_nat_async_mask_value = mask; | |
b84876c2 PA |
4068 | } |
4069 | else | |
4070 | { | |
b84876c2 PA |
4071 | linux_nat_async_mask_value = mask; |
4072 | linux_nat_async (inferior_event_handler, 0); | |
4073 | } | |
4074 | } | |
4075 | ||
4076 | return current_state; | |
4077 | } | |
4078 | ||
4079 | /* Pop an event from the event pipe. */ | |
4080 | ||
4081 | static int | |
4082 | linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options) | |
4083 | { | |
4084 | struct waitpid_result event = {0}; | |
4085 | int ret; | |
4086 | ||
4087 | do | |
4088 | { | |
4089 | ret = read (linux_nat_event_pipe[0], &event, sizeof (event)); | |
4090 | } | |
4091 | while (ret == -1 && errno == EINTR); | |
4092 | ||
4093 | gdb_assert (ret == sizeof (event)); | |
4094 | ||
4095 | *ptr_status = event.status; | |
4096 | *ptr_options = event.options; | |
4097 | ||
4098 | linux_nat_num_queued_events--; | |
4099 | ||
4100 | return event.pid; | |
4101 | } | |
4102 | ||
4103 | /* Push an event into the event pipe. */ | |
4104 | ||
4105 | static void | |
4106 | linux_nat_event_pipe_push (int pid, int status, int options) | |
4107 | { | |
4108 | int ret; | |
4109 | struct waitpid_result event = {0}; | |
4110 | event.pid = pid; | |
4111 | event.status = status; | |
4112 | event.options = options; | |
4113 | ||
4114 | do | |
4115 | { | |
4116 | ret = write (linux_nat_event_pipe[1], &event, sizeof (event)); | |
4117 | gdb_assert ((ret == -1 && errno == EINTR) || ret == sizeof (event)); | |
4118 | } while (ret == -1 && errno == EINTR); | |
4119 | ||
4120 | linux_nat_num_queued_events++; | |
4121 | } | |
4122 | ||
4123 | static void | |
4124 | get_pending_events (void) | |
4125 | { | |
4126 | int status, options, pid; | |
4127 | ||
84e46146 PA |
4128 | if (!linux_nat_async_enabled |
4129 | || linux_nat_async_events_state != sigchld_async) | |
b84876c2 PA |
4130 | internal_error (__FILE__, __LINE__, |
4131 | "get_pending_events called with async masked"); | |
4132 | ||
4133 | while (1) | |
4134 | { | |
4135 | status = 0; | |
4136 | options = __WCLONE | WNOHANG; | |
4137 | ||
4138 | do | |
4139 | { | |
4140 | pid = waitpid (-1, &status, options); | |
4141 | } | |
4142 | while (pid == -1 && errno == EINTR); | |
4143 | ||
4144 | if (pid <= 0) | |
4145 | { | |
4146 | options = WNOHANG; | |
4147 | do | |
4148 | { | |
4149 | pid = waitpid (-1, &status, options); | |
4150 | } | |
4151 | while (pid == -1 && errno == EINTR); | |
4152 | } | |
4153 | ||
4154 | if (pid <= 0) | |
4155 | /* No more children reporting events. */ | |
4156 | break; | |
4157 | ||
4158 | if (debug_linux_nat_async) | |
4159 | fprintf_unfiltered (gdb_stdlog, "\ | |
4160 | get_pending_events: pid(%d), status(%x), options (%x)\n", | |
4161 | pid, status, options); | |
4162 | ||
4163 | linux_nat_event_pipe_push (pid, status, options); | |
4164 | } | |
4165 | ||
4166 | if (debug_linux_nat_async) | |
4167 | fprintf_unfiltered (gdb_stdlog, "\ | |
4168 | get_pending_events: linux_nat_num_queued_events(%d)\n", | |
4169 | linux_nat_num_queued_events); | |
4170 | } | |
4171 | ||
4172 | /* SIGCHLD handler for async mode. */ | |
4173 | ||
4174 | static void | |
4175 | async_sigchld_handler (int signo) | |
4176 | { | |
4177 | if (debug_linux_nat_async) | |
4178 | fprintf_unfiltered (gdb_stdlog, "async_sigchld_handler\n"); | |
4179 | ||
4180 | get_pending_events (); | |
4181 | } | |
4182 | ||
84e46146 | 4183 | /* Set SIGCHLD handling state to STATE. Returns previous state. */ |
b84876c2 | 4184 | |
84e46146 PA |
4185 | static enum sigchld_state |
4186 | linux_nat_async_events (enum sigchld_state state) | |
b84876c2 | 4187 | { |
84e46146 | 4188 | enum sigchld_state current_state = linux_nat_async_events_state; |
b84876c2 PA |
4189 | |
4190 | if (debug_linux_nat_async) | |
4191 | fprintf_unfiltered (gdb_stdlog, | |
84e46146 | 4192 | "LNAE: state(%d): linux_nat_async_events_state(%d), " |
b84876c2 | 4193 | "linux_nat_num_queued_events(%d)\n", |
84e46146 | 4194 | state, linux_nat_async_events_state, |
b84876c2 PA |
4195 | linux_nat_num_queued_events); |
4196 | ||
84e46146 | 4197 | if (current_state != state) |
b84876c2 PA |
4198 | { |
4199 | sigset_t mask; | |
4200 | sigemptyset (&mask); | |
4201 | sigaddset (&mask, SIGCHLD); | |
84e46146 PA |
4202 | |
4203 | /* Always block before changing state. */ | |
4204 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4205 | ||
4206 | /* Set new state. */ | |
4207 | linux_nat_async_events_state = state; | |
4208 | ||
4209 | switch (state) | |
b84876c2 | 4210 | { |
84e46146 PA |
4211 | case sigchld_sync: |
4212 | { | |
4213 | /* Block target events. */ | |
4214 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4215 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
4216 | /* Get events out of queue, and make them available to | |
4217 | queued_waitpid / my_waitpid. */ | |
4218 | pipe_to_local_event_queue (); | |
4219 | } | |
4220 | break; | |
4221 | case sigchld_async: | |
4222 | { | |
4223 | /* Unblock target events for async mode. */ | |
4224 | ||
4225 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4226 | ||
4227 | /* Put events we already waited on, in the pipe first, so | |
4228 | events are FIFO. */ | |
4229 | local_event_queue_to_pipe (); | |
4230 | /* While in masked async, we may have not collected all | |
4231 | the pending events. Get them out now. */ | |
4232 | get_pending_events (); | |
4233 | ||
4234 | /* Let'em come. */ | |
4235 | sigaction (SIGCHLD, &async_sigchld_action, NULL); | |
4236 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
4237 | } | |
4238 | break; | |
4239 | case sigchld_default: | |
4240 | { | |
4241 | /* SIGCHLD default mode. */ | |
4242 | sigaction (SIGCHLD, &sigchld_default_action, NULL); | |
4243 | ||
4244 | /* Get events out of queue, and make them available to | |
4245 | queued_waitpid / my_waitpid. */ | |
4246 | pipe_to_local_event_queue (); | |
4247 | ||
4248 | /* Unblock SIGCHLD. */ | |
4249 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
4250 | } | |
4251 | break; | |
b84876c2 PA |
4252 | } |
4253 | } | |
4254 | ||
4255 | return current_state; | |
4256 | } | |
4257 | ||
4258 | static int async_terminal_is_ours = 1; | |
4259 | ||
4260 | /* target_terminal_inferior implementation. */ | |
4261 | ||
4262 | static void | |
4263 | linux_nat_terminal_inferior (void) | |
4264 | { | |
4265 | if (!target_is_async_p ()) | |
4266 | { | |
4267 | /* Async mode is disabled. */ | |
4268 | terminal_inferior (); | |
4269 | return; | |
4270 | } | |
4271 | ||
4272 | /* GDB should never give the terminal to the inferior, if the | |
4273 | inferior is running in the background (run&, continue&, etc.). | |
4274 | This check can be removed when the common code is fixed. */ | |
4275 | if (!sync_execution) | |
4276 | return; | |
4277 | ||
4278 | terminal_inferior (); | |
4279 | ||
4280 | if (!async_terminal_is_ours) | |
4281 | return; | |
4282 | ||
4283 | delete_file_handler (input_fd); | |
4284 | async_terminal_is_ours = 0; | |
4285 | set_sigint_trap (); | |
4286 | } | |
4287 | ||
4288 | /* target_terminal_ours implementation. */ | |
4289 | ||
4290 | void | |
4291 | linux_nat_terminal_ours (void) | |
4292 | { | |
4293 | if (!target_is_async_p ()) | |
4294 | { | |
4295 | /* Async mode is disabled. */ | |
4296 | terminal_ours (); | |
4297 | return; | |
4298 | } | |
4299 | ||
4300 | /* GDB should never give the terminal to the inferior if the | |
4301 | inferior is running in the background (run&, continue&, etc.), | |
4302 | but claiming it sure should. */ | |
4303 | terminal_ours (); | |
4304 | ||
4305 | if (!sync_execution) | |
4306 | return; | |
4307 | ||
4308 | if (async_terminal_is_ours) | |
4309 | return; | |
4310 | ||
4311 | clear_sigint_trap (); | |
4312 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4313 | async_terminal_is_ours = 1; | |
4314 | } | |
4315 | ||
4316 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4317 | void *context); | |
4318 | static void *async_client_context; | |
4319 | ||
4320 | static void | |
4321 | linux_nat_async_file_handler (int error, gdb_client_data client_data) | |
4322 | { | |
4323 | async_client_callback (INF_REG_EVENT, async_client_context); | |
4324 | } | |
4325 | ||
4326 | /* target_async implementation. */ | |
4327 | ||
4328 | static void | |
4329 | linux_nat_async (void (*callback) (enum inferior_event_type event_type, | |
4330 | void *context), void *context) | |
4331 | { | |
4332 | if (linux_nat_async_mask_value == 0 || !linux_nat_async_enabled) | |
4333 | internal_error (__FILE__, __LINE__, | |
4334 | "Calling target_async when async is masked"); | |
4335 | ||
4336 | if (callback != NULL) | |
4337 | { | |
4338 | async_client_callback = callback; | |
4339 | async_client_context = context; | |
4340 | add_file_handler (linux_nat_event_pipe[0], | |
4341 | linux_nat_async_file_handler, NULL); | |
4342 | ||
84e46146 | 4343 | linux_nat_async_events (sigchld_async); |
b84876c2 PA |
4344 | } |
4345 | else | |
4346 | { | |
4347 | async_client_callback = callback; | |
4348 | async_client_context = context; | |
4349 | ||
84e46146 | 4350 | linux_nat_async_events (sigchld_sync); |
b84876c2 PA |
4351 | delete_file_handler (linux_nat_event_pipe[0]); |
4352 | } | |
4353 | return; | |
4354 | } | |
4355 | ||
4356 | /* Enable/Disable async mode. */ | |
4357 | ||
4358 | static void | |
4359 | linux_nat_set_async_mode (int on) | |
4360 | { | |
4361 | if (linux_nat_async_enabled != on) | |
4362 | { | |
4363 | if (on) | |
4364 | { | |
4365 | gdb_assert (waitpid_queue == NULL); | |
b84876c2 PA |
4366 | if (pipe (linux_nat_event_pipe) == -1) |
4367 | internal_error (__FILE__, __LINE__, | |
4368 | "creating event pipe failed."); | |
b84876c2 PA |
4369 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); |
4370 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4371 | } | |
4372 | else | |
4373 | { | |
b84876c2 | 4374 | drain_queued_events (-1); |
b84876c2 PA |
4375 | linux_nat_num_queued_events = 0; |
4376 | close (linux_nat_event_pipe[0]); | |
4377 | close (linux_nat_event_pipe[1]); | |
4378 | linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1; | |
4379 | ||
4380 | } | |
4381 | } | |
4382 | linux_nat_async_enabled = on; | |
4383 | } | |
4384 | ||
4c28f408 PA |
4385 | static int |
4386 | send_sigint_callback (struct lwp_info *lp, void *data) | |
4387 | { | |
4388 | /* Use is_running instead of !lp->stopped, because the lwp may be | |
4389 | stopped due to an internal event, and we want to interrupt it in | |
4390 | that case too. What we want is to check if the thread is stopped | |
4391 | from the point of view of the user. */ | |
4392 | if (is_running (lp->ptid)) | |
4393 | kill_lwp (GET_LWP (lp->ptid), SIGINT); | |
4394 | return 0; | |
4395 | } | |
4396 | ||
4397 | static void | |
4398 | linux_nat_stop (ptid_t ptid) | |
4399 | { | |
4400 | if (non_stop) | |
4401 | { | |
4402 | if (ptid_equal (ptid, minus_one_ptid)) | |
4403 | iterate_over_lwps (send_sigint_callback, &ptid); | |
4404 | else | |
4405 | { | |
4406 | struct lwp_info *lp = find_lwp_pid (ptid); | |
4407 | send_sigint_callback (lp, NULL); | |
4408 | } | |
4409 | } | |
4410 | else | |
4411 | linux_ops->to_stop (ptid); | |
4412 | } | |
4413 | ||
f973ed9c DJ |
4414 | void |
4415 | linux_nat_add_target (struct target_ops *t) | |
4416 | { | |
f973ed9c DJ |
4417 | /* Save the provided single-threaded target. We save this in a separate |
4418 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4419 | may have saved a pointer to T; we want to use it for the final | |
4420 | process stratum target. */ | |
4421 | linux_ops_saved = *t; | |
4422 | linux_ops = &linux_ops_saved; | |
4423 | ||
4424 | /* Override some methods for multithreading. */ | |
b84876c2 | 4425 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4426 | t->to_attach = linux_nat_attach; |
4427 | t->to_detach = linux_nat_detach; | |
4428 | t->to_resume = linux_nat_resume; | |
4429 | t->to_wait = linux_nat_wait; | |
4430 | t->to_xfer_partial = linux_nat_xfer_partial; | |
4431 | t->to_kill = linux_nat_kill; | |
4432 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4433 | t->to_thread_alive = linux_nat_thread_alive; | |
4434 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4435 | t->to_has_thread_control = tc_schedlock; | |
4436 | ||
b84876c2 PA |
4437 | t->to_can_async_p = linux_nat_can_async_p; |
4438 | t->to_is_async_p = linux_nat_is_async_p; | |
4439 | t->to_async = linux_nat_async; | |
4440 | t->to_async_mask = linux_nat_async_mask; | |
4441 | t->to_terminal_inferior = linux_nat_terminal_inferior; | |
4442 | t->to_terminal_ours = linux_nat_terminal_ours; | |
4443 | ||
4c28f408 PA |
4444 | /* Methods for non-stop support. */ |
4445 | t->to_stop = linux_nat_stop; | |
4446 | ||
f973ed9c DJ |
4447 | /* We don't change the stratum; this target will sit at |
4448 | process_stratum and thread_db will set at thread_stratum. This | |
4449 | is a little strange, since this is a multi-threaded-capable | |
4450 | target, but we want to be on the stack below thread_db, and we | |
4451 | also want to be used for single-threaded processes. */ | |
4452 | ||
4453 | add_target (t); | |
4454 | ||
4455 | /* TODO: Eliminate this and have libthread_db use | |
4456 | find_target_beneath. */ | |
4457 | thread_db_init (t); | |
4458 | } | |
4459 | ||
9f0bdab8 DJ |
4460 | /* Register a method to call whenever a new thread is attached. */ |
4461 | void | |
4462 | linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t)) | |
4463 | { | |
4464 | /* Save the pointer. We only support a single registered instance | |
4465 | of the GNU/Linux native target, so we do not need to map this to | |
4466 | T. */ | |
4467 | linux_nat_new_thread = new_thread; | |
4468 | } | |
4469 | ||
4470 | /* Return the saved siginfo associated with PTID. */ | |
4471 | struct siginfo * | |
4472 | linux_nat_get_siginfo (ptid_t ptid) | |
4473 | { | |
4474 | struct lwp_info *lp = find_lwp_pid (ptid); | |
4475 | ||
4476 | gdb_assert (lp != NULL); | |
4477 | ||
4478 | return &lp->siginfo; | |
4479 | } | |
4480 | ||
d6b0e80f AC |
4481 | void |
4482 | _initialize_linux_nat (void) | |
4483 | { | |
b84876c2 | 4484 | sigset_t mask; |
dba24537 | 4485 | |
1bedd215 AC |
4486 | add_info ("proc", linux_nat_info_proc_cmd, _("\ |
4487 | Show /proc process information about any running process.\n\ | |
dba24537 AC |
4488 | Specify any process id, or use the program being debugged by default.\n\ |
4489 | Specify any of the following keywords for detailed info:\n\ | |
4490 | mappings -- list of mapped memory regions.\n\ | |
4491 | stat -- list a bunch of random process info.\n\ | |
4492 | status -- list a different bunch of random process info.\n\ | |
1bedd215 | 4493 | all -- list all available /proc info.")); |
d6b0e80f | 4494 | |
b84876c2 PA |
4495 | add_setshow_zinteger_cmd ("lin-lwp", class_maintenance, |
4496 | &debug_linux_nat, _("\ | |
4497 | Set debugging of GNU/Linux lwp module."), _("\ | |
4498 | Show debugging of GNU/Linux lwp module."), _("\ | |
4499 | Enables printf debugging output."), | |
4500 | NULL, | |
4501 | show_debug_linux_nat, | |
4502 | &setdebuglist, &showdebuglist); | |
4503 | ||
4504 | add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance, | |
4505 | &debug_linux_nat_async, _("\ | |
4506 | Set debugging of GNU/Linux async lwp module."), _("\ | |
4507 | Show debugging of GNU/Linux async lwp module."), _("\ | |
4508 | Enables printf debugging output."), | |
4509 | NULL, | |
4510 | show_debug_linux_nat_async, | |
4511 | &setdebuglist, &showdebuglist); | |
4512 | ||
4513 | add_setshow_boolean_cmd ("linux-async", class_maintenance, | |
4514 | &linux_async_permitted_1, _("\ | |
4515 | Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4516 | Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4517 | Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."), | |
4518 | set_maintenance_linux_async_permitted, | |
4519 | show_maintenance_linux_async_permitted, | |
4520 | &maintenance_set_cmdlist, | |
4521 | &maintenance_show_cmdlist); | |
4522 | ||
84e46146 PA |
4523 | /* Get the default SIGCHLD action. Used while forking an inferior |
4524 | (see linux_nat_create_inferior/linux_nat_async_events). */ | |
4525 | sigaction (SIGCHLD, NULL, &sigchld_default_action); | |
4526 | ||
b84876c2 PA |
4527 | /* Block SIGCHLD by default. Doing this early prevents it getting |
4528 | unblocked if an exception is thrown due to an error while the | |
4529 | inferior is starting (sigsetjmp/siglongjmp). */ | |
4530 | sigemptyset (&mask); | |
4531 | sigaddset (&mask, SIGCHLD); | |
4532 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4533 | ||
4534 | /* Save this mask as the default. */ | |
d6b0e80f AC |
4535 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4536 | ||
b84876c2 PA |
4537 | /* The synchronous SIGCHLD handler. */ |
4538 | sync_sigchld_action.sa_handler = sigchld_handler; | |
4539 | sigemptyset (&sync_sigchld_action.sa_mask); | |
4540 | sync_sigchld_action.sa_flags = SA_RESTART; | |
4541 | ||
4542 | /* Make it the default. */ | |
4543 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
d6b0e80f AC |
4544 | |
4545 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4546 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4547 | sigdelset (&suspend_mask, SIGCHLD); | |
4548 | ||
b84876c2 PA |
4549 | /* SIGCHLD handler for async mode. */ |
4550 | async_sigchld_action.sa_handler = async_sigchld_handler; | |
4551 | sigemptyset (&async_sigchld_action.sa_mask); | |
4552 | async_sigchld_action.sa_flags = SA_RESTART; | |
d6b0e80f | 4553 | |
b84876c2 PA |
4554 | /* Install the default mode. */ |
4555 | linux_nat_set_async_mode (linux_async_permitted); | |
10568435 JK |
4556 | |
4557 | add_setshow_boolean_cmd ("disable-randomization", class_support, | |
4558 | &disable_randomization, _("\ | |
4559 | Set disabling of debuggee's virtual address space randomization."), _("\ | |
4560 | Show disabling of debuggee's virtual address space randomization."), _("\ | |
4561 | When this mode is on (which is the default), randomization of the virtual\n\ | |
4562 | address space is disabled. Standalone programs run with the randomization\n\ | |
4563 | enabled by default on some platforms."), | |
4564 | &set_disable_randomization, | |
4565 | &show_disable_randomization, | |
4566 | &setlist, &showlist); | |
d6b0e80f AC |
4567 | } |
4568 | \f | |
4569 | ||
4570 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4571 | the GNU/Linux Threads library and therefore doesn't really belong | |
4572 | here. */ | |
4573 | ||
4574 | /* Read variable NAME in the target and return its value if found. | |
4575 | Otherwise return zero. It is assumed that the type of the variable | |
4576 | is `int'. */ | |
4577 | ||
4578 | static int | |
4579 | get_signo (const char *name) | |
4580 | { | |
4581 | struct minimal_symbol *ms; | |
4582 | int signo; | |
4583 | ||
4584 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
4585 | if (ms == NULL) | |
4586 | return 0; | |
4587 | ||
8e70166d | 4588 | if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
4589 | sizeof (signo)) != 0) |
4590 | return 0; | |
4591 | ||
4592 | return signo; | |
4593 | } | |
4594 | ||
4595 | /* Return the set of signals used by the threads library in *SET. */ | |
4596 | ||
4597 | void | |
4598 | lin_thread_get_thread_signals (sigset_t *set) | |
4599 | { | |
4600 | struct sigaction action; | |
4601 | int restart, cancel; | |
b84876c2 | 4602 | sigset_t blocked_mask; |
d6b0e80f | 4603 | |
b84876c2 | 4604 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
4605 | sigemptyset (set); |
4606 | ||
4607 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
4608 | cancel = get_signo ("__pthread_sig_cancel"); |
4609 | ||
4610 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
4611 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
4612 | not provide any way for the debugger to query the signal numbers - | |
4613 | fortunately they don't change! */ | |
4614 | ||
d6b0e80f | 4615 | if (restart == 0) |
17fbb0bd | 4616 | restart = __SIGRTMIN; |
d6b0e80f | 4617 | |
d6b0e80f | 4618 | if (cancel == 0) |
17fbb0bd | 4619 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
4620 | |
4621 | sigaddset (set, restart); | |
4622 | sigaddset (set, cancel); | |
4623 | ||
4624 | /* The GNU/Linux Threads library makes terminating threads send a | |
4625 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
4626 | those (to prevent them from terminating GDB itself, which is | |
4627 | likely to be their default action) and treat them the same way as | |
4628 | SIGCHLD. */ | |
4629 | ||
4630 | action.sa_handler = sigchld_handler; | |
4631 | sigemptyset (&action.sa_mask); | |
58aecb61 | 4632 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
4633 | sigaction (cancel, &action, NULL); |
4634 | ||
4635 | /* We block the "cancel" signal throughout this code ... */ | |
4636 | sigaddset (&blocked_mask, cancel); | |
4637 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
4638 | ||
4639 | /* ... except during a sigsuspend. */ | |
4640 | sigdelset (&suspend_mask, cancel); | |
4641 | } |