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 PA |
321 | |
322 | /* Captures the result of a successful waitpid call, along with the | |
323 | options used in that call. */ | |
324 | struct waitpid_result | |
325 | { | |
326 | int pid; | |
327 | int status; | |
328 | int options; | |
329 | struct waitpid_result *next; | |
330 | }; | |
331 | ||
332 | /* A singly-linked list of the results of the waitpid calls performed | |
333 | in the async SIGCHLD handler. */ | |
334 | static struct waitpid_result *waitpid_queue = NULL; | |
335 | ||
336 | static int | |
337 | queued_waitpid (int pid, int *status, int flags) | |
338 | { | |
339 | struct waitpid_result *msg = waitpid_queue, *prev = NULL; | |
340 | ||
341 | if (debug_linux_nat_async) | |
342 | fprintf_unfiltered (gdb_stdlog, | |
343 | "\ | |
84e46146 PA |
344 | QWPID: linux_nat_async_events_state(%d), linux_nat_num_queued_events(%d)\n", |
345 | linux_nat_async_events_state, | |
b84876c2 PA |
346 | linux_nat_num_queued_events); |
347 | ||
348 | if (flags & __WALL) | |
349 | { | |
350 | for (; msg; prev = msg, msg = msg->next) | |
351 | if (pid == -1 || pid == msg->pid) | |
352 | break; | |
353 | } | |
354 | else if (flags & __WCLONE) | |
355 | { | |
356 | for (; msg; prev = msg, msg = msg->next) | |
357 | if (msg->options & __WCLONE | |
358 | && (pid == -1 || pid == msg->pid)) | |
359 | break; | |
360 | } | |
361 | else | |
362 | { | |
363 | for (; msg; prev = msg, msg = msg->next) | |
364 | if ((msg->options & __WCLONE) == 0 | |
365 | && (pid == -1 || pid == msg->pid)) | |
366 | break; | |
367 | } | |
368 | ||
369 | if (msg) | |
370 | { | |
371 | int pid; | |
372 | ||
373 | if (prev) | |
374 | prev->next = msg->next; | |
375 | else | |
376 | waitpid_queue = msg->next; | |
377 | ||
378 | msg->next = NULL; | |
379 | if (status) | |
380 | *status = msg->status; | |
381 | pid = msg->pid; | |
382 | ||
383 | if (debug_linux_nat_async) | |
384 | fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n", | |
385 | pid, msg->status); | |
386 | xfree (msg); | |
387 | ||
388 | return pid; | |
389 | } | |
390 | ||
391 | if (debug_linux_nat_async) | |
392 | fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n"); | |
393 | ||
394 | if (status) | |
395 | *status = 0; | |
396 | return -1; | |
397 | } | |
398 | ||
399 | static void | |
400 | push_waitpid (int pid, int status, int options) | |
401 | { | |
402 | struct waitpid_result *event, *new_event; | |
403 | ||
404 | new_event = xmalloc (sizeof (*new_event)); | |
405 | new_event->pid = pid; | |
406 | new_event->status = status; | |
407 | new_event->options = options; | |
408 | new_event->next = NULL; | |
409 | ||
410 | if (waitpid_queue) | |
411 | { | |
412 | for (event = waitpid_queue; | |
413 | event && event->next; | |
414 | event = event->next) | |
415 | ; | |
416 | ||
417 | event->next = new_event; | |
418 | } | |
419 | else | |
420 | waitpid_queue = new_event; | |
421 | } | |
422 | ||
710151dd | 423 | /* Drain all queued events of PID. If PID is -1, the effect is of |
b84876c2 PA |
424 | draining all events. */ |
425 | static void | |
426 | drain_queued_events (int pid) | |
427 | { | |
428 | while (queued_waitpid (pid, NULL, __WALL) != -1) | |
429 | ; | |
430 | } | |
431 | ||
ae087d01 DJ |
432 | \f |
433 | /* Trivial list manipulation functions to keep track of a list of | |
434 | new stopped processes. */ | |
435 | static void | |
3d799a95 | 436 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
437 | { |
438 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
439 | new_pid->pid = pid; | |
3d799a95 | 440 | new_pid->status = status; |
ae087d01 DJ |
441 | new_pid->next = *listp; |
442 | *listp = new_pid; | |
443 | } | |
444 | ||
445 | static int | |
3d799a95 | 446 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *status) |
ae087d01 DJ |
447 | { |
448 | struct simple_pid_list **p; | |
449 | ||
450 | for (p = listp; *p != NULL; p = &(*p)->next) | |
451 | if ((*p)->pid == pid) | |
452 | { | |
453 | struct simple_pid_list *next = (*p)->next; | |
3d799a95 | 454 | *status = (*p)->status; |
ae087d01 DJ |
455 | xfree (*p); |
456 | *p = next; | |
457 | return 1; | |
458 | } | |
459 | return 0; | |
460 | } | |
461 | ||
3d799a95 DJ |
462 | static void |
463 | linux_record_stopped_pid (int pid, int status) | |
ae087d01 | 464 | { |
3d799a95 | 465 | add_to_pid_list (&stopped_pids, pid, status); |
ae087d01 DJ |
466 | } |
467 | ||
3993f6b1 DJ |
468 | \f |
469 | /* A helper function for linux_test_for_tracefork, called after fork (). */ | |
470 | ||
471 | static void | |
472 | linux_tracefork_child (void) | |
473 | { | |
474 | int ret; | |
475 | ||
476 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
477 | kill (getpid (), SIGSTOP); | |
478 | fork (); | |
48bb3cce | 479 | _exit (0); |
3993f6b1 DJ |
480 | } |
481 | ||
b84876c2 PA |
482 | /* Wrapper function for waitpid which handles EINTR, and checks for |
483 | locally queued events. */ | |
b957e937 DJ |
484 | |
485 | static int | |
486 | my_waitpid (int pid, int *status, int flags) | |
487 | { | |
488 | int ret; | |
b84876c2 PA |
489 | |
490 | /* There should be no concurrent calls to waitpid. */ | |
84e46146 | 491 | gdb_assert (linux_nat_async_events_state == sigchld_sync); |
b84876c2 PA |
492 | |
493 | ret = queued_waitpid (pid, status, flags); | |
494 | if (ret != -1) | |
495 | return ret; | |
496 | ||
b957e937 DJ |
497 | do |
498 | { | |
499 | ret = waitpid (pid, status, flags); | |
500 | } | |
501 | while (ret == -1 && errno == EINTR); | |
502 | ||
503 | return ret; | |
504 | } | |
505 | ||
506 | /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. | |
507 | ||
508 | First, we try to enable fork tracing on ORIGINAL_PID. If this fails, | |
509 | we know that the feature is not available. This may change the tracing | |
510 | options for ORIGINAL_PID, but we'll be setting them shortly anyway. | |
511 | ||
512 | However, if it succeeds, we don't know for sure that the feature is | |
513 | available; old versions of PTRACE_SETOPTIONS ignored unknown options. We | |
3993f6b1 | 514 | create a child process, attach to it, use PTRACE_SETOPTIONS to enable |
b957e937 DJ |
515 | fork tracing, and let it fork. If the process exits, we assume that we |
516 | can't use TRACEFORK; if we get the fork notification, and we can extract | |
517 | the new child's PID, then we assume that we can. */ | |
3993f6b1 DJ |
518 | |
519 | static void | |
b957e937 | 520 | linux_test_for_tracefork (int original_pid) |
3993f6b1 DJ |
521 | { |
522 | int child_pid, ret, status; | |
523 | long second_pid; | |
524 | ||
b957e937 DJ |
525 | linux_supports_tracefork_flag = 0; |
526 | linux_supports_tracevforkdone_flag = 0; | |
527 | ||
528 | ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK); | |
529 | if (ret != 0) | |
530 | return; | |
531 | ||
3993f6b1 DJ |
532 | child_pid = fork (); |
533 | if (child_pid == -1) | |
e2e0b3e5 | 534 | perror_with_name (("fork")); |
3993f6b1 DJ |
535 | |
536 | if (child_pid == 0) | |
537 | linux_tracefork_child (); | |
538 | ||
b957e937 | 539 | ret = my_waitpid (child_pid, &status, 0); |
3993f6b1 | 540 | if (ret == -1) |
e2e0b3e5 | 541 | perror_with_name (("waitpid")); |
3993f6b1 | 542 | else if (ret != child_pid) |
8a3fe4f8 | 543 | error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret); |
3993f6b1 | 544 | if (! WIFSTOPPED (status)) |
8a3fe4f8 | 545 | error (_("linux_test_for_tracefork: waitpid: unexpected status %d."), status); |
3993f6b1 | 546 | |
3993f6b1 DJ |
547 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK); |
548 | if (ret != 0) | |
549 | { | |
b957e937 DJ |
550 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
551 | if (ret != 0) | |
552 | { | |
8a3fe4f8 | 553 | warning (_("linux_test_for_tracefork: failed to kill child")); |
b957e937 DJ |
554 | return; |
555 | } | |
556 | ||
557 | ret = my_waitpid (child_pid, &status, 0); | |
558 | if (ret != child_pid) | |
8a3fe4f8 | 559 | warning (_("linux_test_for_tracefork: failed to wait for killed child")); |
b957e937 | 560 | else if (!WIFSIGNALED (status)) |
8a3fe4f8 AC |
561 | warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from " |
562 | "killed child"), status); | |
b957e937 | 563 | |
3993f6b1 DJ |
564 | return; |
565 | } | |
566 | ||
9016a515 DJ |
567 | /* Check whether PTRACE_O_TRACEVFORKDONE is available. */ |
568 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, | |
569 | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE); | |
570 | linux_supports_tracevforkdone_flag = (ret == 0); | |
571 | ||
b957e937 DJ |
572 | ret = ptrace (PTRACE_CONT, child_pid, 0, 0); |
573 | if (ret != 0) | |
8a3fe4f8 | 574 | warning (_("linux_test_for_tracefork: failed to resume child")); |
b957e937 DJ |
575 | |
576 | ret = my_waitpid (child_pid, &status, 0); | |
577 | ||
3993f6b1 DJ |
578 | if (ret == child_pid && WIFSTOPPED (status) |
579 | && status >> 16 == PTRACE_EVENT_FORK) | |
580 | { | |
581 | second_pid = 0; | |
582 | ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid); | |
583 | if (ret == 0 && second_pid != 0) | |
584 | { | |
585 | int second_status; | |
586 | ||
587 | linux_supports_tracefork_flag = 1; | |
b957e937 DJ |
588 | my_waitpid (second_pid, &second_status, 0); |
589 | ret = ptrace (PTRACE_KILL, second_pid, 0, 0); | |
590 | if (ret != 0) | |
8a3fe4f8 | 591 | warning (_("linux_test_for_tracefork: failed to kill second child")); |
97725dc4 | 592 | my_waitpid (second_pid, &status, 0); |
3993f6b1 DJ |
593 | } |
594 | } | |
b957e937 | 595 | else |
8a3fe4f8 AC |
596 | warning (_("linux_test_for_tracefork: unexpected result from waitpid " |
597 | "(%d, status 0x%x)"), ret, status); | |
3993f6b1 | 598 | |
b957e937 DJ |
599 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
600 | if (ret != 0) | |
8a3fe4f8 | 601 | warning (_("linux_test_for_tracefork: failed to kill child")); |
b957e937 | 602 | my_waitpid (child_pid, &status, 0); |
3993f6b1 DJ |
603 | } |
604 | ||
605 | /* Return non-zero iff we have tracefork functionality available. | |
606 | This function also sets linux_supports_tracefork_flag. */ | |
607 | ||
608 | static int | |
b957e937 | 609 | linux_supports_tracefork (int pid) |
3993f6b1 DJ |
610 | { |
611 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 612 | linux_test_for_tracefork (pid); |
3993f6b1 DJ |
613 | return linux_supports_tracefork_flag; |
614 | } | |
615 | ||
9016a515 | 616 | static int |
b957e937 | 617 | linux_supports_tracevforkdone (int pid) |
9016a515 DJ |
618 | { |
619 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 620 | linux_test_for_tracefork (pid); |
9016a515 DJ |
621 | return linux_supports_tracevforkdone_flag; |
622 | } | |
623 | ||
3993f6b1 | 624 | \f |
4de4c07c DJ |
625 | void |
626 | linux_enable_event_reporting (ptid_t ptid) | |
627 | { | |
d3587048 | 628 | int pid = ptid_get_lwp (ptid); |
4de4c07c DJ |
629 | int options; |
630 | ||
d3587048 DJ |
631 | if (pid == 0) |
632 | pid = ptid_get_pid (ptid); | |
633 | ||
b957e937 | 634 | if (! linux_supports_tracefork (pid)) |
4de4c07c DJ |
635 | return; |
636 | ||
a2f23071 DJ |
637 | options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC |
638 | | PTRACE_O_TRACECLONE; | |
b957e937 | 639 | if (linux_supports_tracevforkdone (pid)) |
9016a515 DJ |
640 | options |= PTRACE_O_TRACEVFORKDONE; |
641 | ||
642 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support | |
643 | read-only process state. */ | |
4de4c07c DJ |
644 | |
645 | ptrace (PTRACE_SETOPTIONS, pid, 0, options); | |
646 | } | |
647 | ||
6d8fd2b7 UW |
648 | static void |
649 | linux_child_post_attach (int pid) | |
4de4c07c DJ |
650 | { |
651 | linux_enable_event_reporting (pid_to_ptid (pid)); | |
0ec9a092 | 652 | check_for_thread_db (); |
4de4c07c DJ |
653 | } |
654 | ||
10d6c8cd | 655 | static void |
4de4c07c DJ |
656 | linux_child_post_startup_inferior (ptid_t ptid) |
657 | { | |
658 | linux_enable_event_reporting (ptid); | |
0ec9a092 | 659 | check_for_thread_db (); |
4de4c07c DJ |
660 | } |
661 | ||
6d8fd2b7 UW |
662 | static int |
663 | linux_child_follow_fork (struct target_ops *ops, int follow_child) | |
3993f6b1 | 664 | { |
4de4c07c DJ |
665 | ptid_t last_ptid; |
666 | struct target_waitstatus last_status; | |
9016a515 | 667 | int has_vforked; |
4de4c07c DJ |
668 | int parent_pid, child_pid; |
669 | ||
b84876c2 PA |
670 | if (target_can_async_p ()) |
671 | target_async (NULL, 0); | |
672 | ||
4de4c07c | 673 | get_last_target_status (&last_ptid, &last_status); |
9016a515 | 674 | has_vforked = (last_status.kind == TARGET_WAITKIND_VFORKED); |
d3587048 DJ |
675 | parent_pid = ptid_get_lwp (last_ptid); |
676 | if (parent_pid == 0) | |
677 | parent_pid = ptid_get_pid (last_ptid); | |
3a3e9ee3 | 678 | child_pid = PIDGET (last_status.value.related_pid); |
4de4c07c DJ |
679 | |
680 | if (! follow_child) | |
681 | { | |
682 | /* We're already attached to the parent, by default. */ | |
683 | ||
684 | /* Before detaching from the child, remove all breakpoints from | |
685 | it. (This won't actually modify the breakpoint list, but will | |
686 | physically remove the breakpoints from the child.) */ | |
9016a515 DJ |
687 | /* If we vforked this will remove the breakpoints from the parent |
688 | also, but they'll be reinserted below. */ | |
4de4c07c DJ |
689 | detach_breakpoints (child_pid); |
690 | ||
ac264b3b MS |
691 | /* Detach new forked process? */ |
692 | if (detach_fork) | |
f75c00e4 | 693 | { |
e85a822c | 694 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
695 | { |
696 | target_terminal_ours (); | |
697 | fprintf_filtered (gdb_stdlog, | |
698 | "Detaching after fork from child process %d.\n", | |
699 | child_pid); | |
700 | } | |
4de4c07c | 701 | |
ac264b3b MS |
702 | ptrace (PTRACE_DETACH, child_pid, 0, 0); |
703 | } | |
704 | else | |
705 | { | |
706 | struct fork_info *fp; | |
707 | /* Retain child fork in ptrace (stopped) state. */ | |
708 | fp = find_fork_pid (child_pid); | |
709 | if (!fp) | |
710 | fp = add_fork (child_pid); | |
711 | fork_save_infrun_state (fp, 0); | |
712 | } | |
9016a515 DJ |
713 | |
714 | if (has_vforked) | |
715 | { | |
b957e937 DJ |
716 | gdb_assert (linux_supports_tracefork_flag >= 0); |
717 | if (linux_supports_tracevforkdone (0)) | |
9016a515 DJ |
718 | { |
719 | int status; | |
720 | ||
721 | ptrace (PTRACE_CONT, parent_pid, 0, 0); | |
58aecb61 | 722 | my_waitpid (parent_pid, &status, __WALL); |
c874c7fc | 723 | if ((status >> 16) != PTRACE_EVENT_VFORK_DONE) |
8a3fe4f8 AC |
724 | warning (_("Unexpected waitpid result %06x when waiting for " |
725 | "vfork-done"), status); | |
9016a515 DJ |
726 | } |
727 | else | |
728 | { | |
729 | /* We can't insert breakpoints until the child has | |
730 | finished with the shared memory region. We need to | |
731 | wait until that happens. Ideal would be to just | |
732 | call: | |
733 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
734 | - waitpid (parent_pid, &status, __WALL); | |
735 | However, most architectures can't handle a syscall | |
736 | being traced on the way out if it wasn't traced on | |
737 | the way in. | |
738 | ||
739 | We might also think to loop, continuing the child | |
740 | until it exits or gets a SIGTRAP. One problem is | |
741 | that the child might call ptrace with PTRACE_TRACEME. | |
742 | ||
743 | There's no simple and reliable way to figure out when | |
744 | the vforked child will be done with its copy of the | |
745 | shared memory. We could step it out of the syscall, | |
746 | two instructions, let it go, and then single-step the | |
747 | parent once. When we have hardware single-step, this | |
748 | would work; with software single-step it could still | |
749 | be made to work but we'd have to be able to insert | |
750 | single-step breakpoints in the child, and we'd have | |
751 | to insert -just- the single-step breakpoint in the | |
752 | parent. Very awkward. | |
753 | ||
754 | In the end, the best we can do is to make sure it | |
755 | runs for a little while. Hopefully it will be out of | |
756 | range of any breakpoints we reinsert. Usually this | |
757 | is only the single-step breakpoint at vfork's return | |
758 | point. */ | |
759 | ||
760 | usleep (10000); | |
761 | } | |
762 | ||
763 | /* Since we vforked, breakpoints were removed in the parent | |
764 | too. Put them back. */ | |
765 | reattach_breakpoints (parent_pid); | |
766 | } | |
4de4c07c | 767 | } |
3993f6b1 | 768 | else |
4de4c07c DJ |
769 | { |
770 | char child_pid_spelling[40]; | |
771 | ||
772 | /* Needed to keep the breakpoint lists in sync. */ | |
9016a515 DJ |
773 | if (! has_vforked) |
774 | detach_breakpoints (child_pid); | |
4de4c07c DJ |
775 | |
776 | /* Before detaching from the parent, remove all breakpoints from it. */ | |
777 | remove_breakpoints (); | |
778 | ||
e85a822c | 779 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
780 | { |
781 | target_terminal_ours (); | |
ac264b3b MS |
782 | fprintf_filtered (gdb_stdlog, |
783 | "Attaching after fork to child process %d.\n", | |
784 | child_pid); | |
f75c00e4 | 785 | } |
4de4c07c | 786 | |
9016a515 DJ |
787 | /* If we're vforking, we may want to hold on to the parent until |
788 | the child exits or execs. At exec time we can remove the old | |
789 | breakpoints from the parent and detach it; at exit time we | |
790 | could do the same (or even, sneakily, resume debugging it - the | |
791 | child's exec has failed, or something similar). | |
792 | ||
793 | This doesn't clean up "properly", because we can't call | |
794 | target_detach, but that's OK; if the current target is "child", | |
795 | then it doesn't need any further cleanups, and lin_lwp will | |
796 | generally not encounter vfork (vfork is defined to fork | |
797 | in libpthread.so). | |
798 | ||
799 | The holding part is very easy if we have VFORKDONE events; | |
800 | but keeping track of both processes is beyond GDB at the | |
801 | moment. So we don't expose the parent to the rest of GDB. | |
802 | Instead we quietly hold onto it until such time as we can | |
803 | safely resume it. */ | |
804 | ||
805 | if (has_vforked) | |
806 | linux_parent_pid = parent_pid; | |
ac264b3b MS |
807 | else if (!detach_fork) |
808 | { | |
809 | struct fork_info *fp; | |
810 | /* Retain parent fork in ptrace (stopped) state. */ | |
811 | fp = find_fork_pid (parent_pid); | |
812 | if (!fp) | |
813 | fp = add_fork (parent_pid); | |
814 | fork_save_infrun_state (fp, 0); | |
815 | } | |
9016a515 | 816 | else |
b84876c2 | 817 | target_detach (NULL, 0); |
4de4c07c | 818 | |
9f0bdab8 | 819 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
ee057212 DJ |
820 | |
821 | /* Reinstall ourselves, since we might have been removed in | |
822 | target_detach (which does other necessary cleanup). */ | |
ac264b3b | 823 | |
ee057212 | 824 | push_target (ops); |
9f0bdab8 | 825 | linux_nat_switch_fork (inferior_ptid); |
ef29ce1a | 826 | check_for_thread_db (); |
4de4c07c DJ |
827 | |
828 | /* Reset breakpoints in the child as appropriate. */ | |
829 | follow_inferior_reset_breakpoints (); | |
830 | } | |
831 | ||
b84876c2 PA |
832 | if (target_can_async_p ()) |
833 | target_async (inferior_event_handler, 0); | |
834 | ||
4de4c07c DJ |
835 | return 0; |
836 | } | |
837 | ||
4de4c07c | 838 | \f |
6d8fd2b7 UW |
839 | static void |
840 | linux_child_insert_fork_catchpoint (int pid) | |
4de4c07c | 841 | { |
b957e937 | 842 | if (! linux_supports_tracefork (pid)) |
8a3fe4f8 | 843 | error (_("Your system does not support fork catchpoints.")); |
3993f6b1 DJ |
844 | } |
845 | ||
6d8fd2b7 UW |
846 | static void |
847 | linux_child_insert_vfork_catchpoint (int pid) | |
3993f6b1 | 848 | { |
b957e937 | 849 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 850 | error (_("Your system does not support vfork catchpoints.")); |
3993f6b1 DJ |
851 | } |
852 | ||
6d8fd2b7 UW |
853 | static void |
854 | linux_child_insert_exec_catchpoint (int pid) | |
3993f6b1 | 855 | { |
b957e937 | 856 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 857 | error (_("Your system does not support exec catchpoints.")); |
3993f6b1 DJ |
858 | } |
859 | ||
d6b0e80f AC |
860 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
861 | are processes sharing the same VM space. A multi-threaded process | |
862 | is basically a group of such processes. However, such a grouping | |
863 | is almost entirely a user-space issue; the kernel doesn't enforce | |
864 | such a grouping at all (this might change in the future). In | |
865 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
866 | Threads library) to provide such a grouping. | |
867 | ||
868 | It is perfectly well possible to write a multi-threaded application | |
869 | without the assistance of a threads library, by using the clone | |
870 | system call directly. This module should be able to give some | |
871 | rudimentary support for debugging such applications if developers | |
872 | specify the CLONE_PTRACE flag in the clone system call, and are | |
873 | using the Linux kernel 2.4 or above. | |
874 | ||
875 | Note that there are some peculiarities in GNU/Linux that affect | |
876 | this code: | |
877 | ||
878 | - In general one should specify the __WCLONE flag to waitpid in | |
879 | order to make it report events for any of the cloned processes | |
880 | (and leave it out for the initial process). However, if a cloned | |
881 | process has exited the exit status is only reported if the | |
882 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
883 | we cannot use it since GDB must work on older systems too. | |
884 | ||
885 | - When a traced, cloned process exits and is waited for by the | |
886 | debugger, the kernel reassigns it to the original parent and | |
887 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
888 | library doesn't notice this, which leads to the "zombie problem": | |
889 | When debugged a multi-threaded process that spawns a lot of | |
890 | threads will run out of processes, even if the threads exit, | |
891 | because the "zombies" stay around. */ | |
892 | ||
893 | /* List of known LWPs. */ | |
9f0bdab8 | 894 | struct lwp_info *lwp_list; |
d6b0e80f AC |
895 | |
896 | /* Number of LWPs in the list. */ | |
897 | static int num_lwps; | |
d6b0e80f AC |
898 | \f |
899 | ||
d6b0e80f AC |
900 | /* Original signal mask. */ |
901 | static sigset_t normal_mask; | |
902 | ||
903 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
904 | _initialize_linux_nat. */ | |
905 | static sigset_t suspend_mask; | |
906 | ||
b84876c2 PA |
907 | /* SIGCHLD action for synchronous mode. */ |
908 | struct sigaction sync_sigchld_action; | |
909 | ||
910 | /* SIGCHLD action for asynchronous mode. */ | |
911 | static struct sigaction async_sigchld_action; | |
84e46146 PA |
912 | |
913 | /* SIGCHLD default action, to pass to new inferiors. */ | |
914 | static struct sigaction sigchld_default_action; | |
d6b0e80f AC |
915 | \f |
916 | ||
917 | /* Prototypes for local functions. */ | |
918 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
919 | static int linux_nat_thread_alive (ptid_t ptid); | |
6d8fd2b7 | 920 | static char *linux_child_pid_to_exec_file (int pid); |
710151dd PA |
921 | static int cancel_breakpoint (struct lwp_info *lp); |
922 | ||
d6b0e80f AC |
923 | \f |
924 | /* Convert wait status STATUS to a string. Used for printing debug | |
925 | messages only. */ | |
926 | ||
927 | static char * | |
928 | status_to_str (int status) | |
929 | { | |
930 | static char buf[64]; | |
931 | ||
932 | if (WIFSTOPPED (status)) | |
933 | snprintf (buf, sizeof (buf), "%s (stopped)", | |
934 | strsignal (WSTOPSIG (status))); | |
935 | else if (WIFSIGNALED (status)) | |
936 | snprintf (buf, sizeof (buf), "%s (terminated)", | |
937 | strsignal (WSTOPSIG (status))); | |
938 | else | |
939 | snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status)); | |
940 | ||
941 | return buf; | |
942 | } | |
943 | ||
944 | /* Initialize the list of LWPs. Note that this module, contrary to | |
945 | what GDB's generic threads layer does for its thread list, | |
946 | re-initializes the LWP lists whenever we mourn or detach (which | |
947 | doesn't involve mourning) the inferior. */ | |
948 | ||
949 | static void | |
950 | init_lwp_list (void) | |
951 | { | |
952 | struct lwp_info *lp, *lpnext; | |
953 | ||
954 | for (lp = lwp_list; lp; lp = lpnext) | |
955 | { | |
956 | lpnext = lp->next; | |
957 | xfree (lp); | |
958 | } | |
959 | ||
960 | lwp_list = NULL; | |
961 | num_lwps = 0; | |
d6b0e80f AC |
962 | } |
963 | ||
f973ed9c | 964 | /* Add the LWP specified by PID to the list. Return a pointer to the |
9f0bdab8 DJ |
965 | structure describing the new LWP. The LWP should already be stopped |
966 | (with an exception for the very first LWP). */ | |
d6b0e80f AC |
967 | |
968 | static struct lwp_info * | |
969 | add_lwp (ptid_t ptid) | |
970 | { | |
971 | struct lwp_info *lp; | |
972 | ||
973 | gdb_assert (is_lwp (ptid)); | |
974 | ||
975 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
976 | ||
977 | memset (lp, 0, sizeof (struct lwp_info)); | |
978 | ||
979 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
980 | ||
981 | lp->ptid = ptid; | |
982 | ||
983 | lp->next = lwp_list; | |
984 | lwp_list = lp; | |
f973ed9c | 985 | ++num_lwps; |
d6b0e80f | 986 | |
9f0bdab8 DJ |
987 | if (num_lwps > 1 && linux_nat_new_thread != NULL) |
988 | linux_nat_new_thread (ptid); | |
989 | ||
d6b0e80f AC |
990 | return lp; |
991 | } | |
992 | ||
993 | /* Remove the LWP specified by PID from the list. */ | |
994 | ||
995 | static void | |
996 | delete_lwp (ptid_t ptid) | |
997 | { | |
998 | struct lwp_info *lp, *lpprev; | |
999 | ||
1000 | lpprev = NULL; | |
1001 | ||
1002 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
1003 | if (ptid_equal (lp->ptid, ptid)) | |
1004 | break; | |
1005 | ||
1006 | if (!lp) | |
1007 | return; | |
1008 | ||
d6b0e80f AC |
1009 | num_lwps--; |
1010 | ||
1011 | if (lpprev) | |
1012 | lpprev->next = lp->next; | |
1013 | else | |
1014 | lwp_list = lp->next; | |
1015 | ||
1016 | xfree (lp); | |
1017 | } | |
1018 | ||
1019 | /* Return a pointer to the structure describing the LWP corresponding | |
1020 | to PID. If no corresponding LWP could be found, return NULL. */ | |
1021 | ||
1022 | static struct lwp_info * | |
1023 | find_lwp_pid (ptid_t ptid) | |
1024 | { | |
1025 | struct lwp_info *lp; | |
1026 | int lwp; | |
1027 | ||
1028 | if (is_lwp (ptid)) | |
1029 | lwp = GET_LWP (ptid); | |
1030 | else | |
1031 | lwp = GET_PID (ptid); | |
1032 | ||
1033 | for (lp = lwp_list; lp; lp = lp->next) | |
1034 | if (lwp == GET_LWP (lp->ptid)) | |
1035 | return lp; | |
1036 | ||
1037 | return NULL; | |
1038 | } | |
1039 | ||
1040 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
1041 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
1042 | pointer to the structure describing that LWP immediately. | |
1043 | Otherwise return NULL. */ | |
1044 | ||
1045 | struct lwp_info * | |
1046 | iterate_over_lwps (int (*callback) (struct lwp_info *, void *), void *data) | |
1047 | { | |
1048 | struct lwp_info *lp, *lpnext; | |
1049 | ||
1050 | for (lp = lwp_list; lp; lp = lpnext) | |
1051 | { | |
1052 | lpnext = lp->next; | |
1053 | if ((*callback) (lp, data)) | |
1054 | return lp; | |
1055 | } | |
1056 | ||
1057 | return NULL; | |
1058 | } | |
1059 | ||
f973ed9c DJ |
1060 | /* Update our internal state when changing from one fork (checkpoint, |
1061 | et cetera) to another indicated by NEW_PTID. We can only switch | |
1062 | single-threaded applications, so we only create one new LWP, and | |
1063 | the previous list is discarded. */ | |
1064 | ||
1065 | void | |
1066 | linux_nat_switch_fork (ptid_t new_ptid) | |
1067 | { | |
1068 | struct lwp_info *lp; | |
1069 | ||
728c8f58 | 1070 | init_thread_list (); |
f973ed9c DJ |
1071 | init_lwp_list (); |
1072 | lp = add_lwp (new_ptid); | |
728c8f58 | 1073 | add_thread_silent (new_ptid); |
f973ed9c DJ |
1074 | lp->stopped = 1; |
1075 | } | |
1076 | ||
e26af52f DJ |
1077 | /* Record a PTID for later deletion. */ |
1078 | ||
1079 | struct saved_ptids | |
1080 | { | |
1081 | ptid_t ptid; | |
1082 | struct saved_ptids *next; | |
1083 | }; | |
1084 | static struct saved_ptids *threads_to_delete; | |
1085 | ||
1086 | static void | |
1087 | record_dead_thread (ptid_t ptid) | |
1088 | { | |
1089 | struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids)); | |
1090 | p->ptid = ptid; | |
1091 | p->next = threads_to_delete; | |
1092 | threads_to_delete = p; | |
1093 | } | |
1094 | ||
1095 | /* Delete any dead threads which are not the current thread. */ | |
1096 | ||
1097 | static void | |
1098 | prune_lwps (void) | |
1099 | { | |
1100 | struct saved_ptids **p = &threads_to_delete; | |
1101 | ||
1102 | while (*p) | |
1103 | if (! ptid_equal ((*p)->ptid, inferior_ptid)) | |
1104 | { | |
1105 | struct saved_ptids *tmp = *p; | |
1106 | delete_thread (tmp->ptid); | |
1107 | *p = tmp->next; | |
1108 | xfree (tmp); | |
1109 | } | |
1110 | else | |
1111 | p = &(*p)->next; | |
1112 | } | |
1113 | ||
e26af52f DJ |
1114 | /* Handle the exit of a single thread LP. */ |
1115 | ||
1116 | static void | |
1117 | exit_lwp (struct lwp_info *lp) | |
1118 | { | |
063bfe2e VP |
1119 | struct thread_info *th = find_thread_pid (lp->ptid); |
1120 | ||
1121 | if (th) | |
e26af52f | 1122 | { |
17faa917 DJ |
1123 | if (print_thread_events) |
1124 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1125 | ||
e26af52f DJ |
1126 | /* Core GDB cannot deal with us deleting the current thread. */ |
1127 | if (!ptid_equal (lp->ptid, inferior_ptid)) | |
1128 | delete_thread (lp->ptid); | |
1129 | else | |
1130 | record_dead_thread (lp->ptid); | |
e26af52f DJ |
1131 | } |
1132 | ||
1133 | delete_lwp (lp->ptid); | |
1134 | } | |
1135 | ||
a0ef4274 DJ |
1136 | /* Detect `T (stopped)' in `/proc/PID/status'. |
1137 | Other states including `T (tracing stop)' are reported as false. */ | |
1138 | ||
1139 | static int | |
1140 | pid_is_stopped (pid_t pid) | |
1141 | { | |
1142 | FILE *status_file; | |
1143 | char buf[100]; | |
1144 | int retval = 0; | |
1145 | ||
1146 | snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid); | |
1147 | status_file = fopen (buf, "r"); | |
1148 | if (status_file != NULL) | |
1149 | { | |
1150 | int have_state = 0; | |
1151 | ||
1152 | while (fgets (buf, sizeof (buf), status_file)) | |
1153 | { | |
1154 | if (strncmp (buf, "State:", 6) == 0) | |
1155 | { | |
1156 | have_state = 1; | |
1157 | break; | |
1158 | } | |
1159 | } | |
1160 | if (have_state && strstr (buf, "T (stopped)") != NULL) | |
1161 | retval = 1; | |
1162 | fclose (status_file); | |
1163 | } | |
1164 | return retval; | |
1165 | } | |
1166 | ||
1167 | /* Wait for the LWP specified by LP, which we have just attached to. | |
1168 | Returns a wait status for that LWP, to cache. */ | |
1169 | ||
1170 | static int | |
1171 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1172 | int *signalled) | |
1173 | { | |
1174 | pid_t new_pid, pid = GET_LWP (ptid); | |
1175 | int status; | |
1176 | ||
1177 | if (pid_is_stopped (pid)) | |
1178 | { | |
1179 | if (debug_linux_nat) | |
1180 | fprintf_unfiltered (gdb_stdlog, | |
1181 | "LNPAW: Attaching to a stopped process\n"); | |
1182 | ||
1183 | /* The process is definitely stopped. It is in a job control | |
1184 | stop, unless the kernel predates the TASK_STOPPED / | |
1185 | TASK_TRACED distinction, in which case it might be in a | |
1186 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1187 | can kill it, signal it, et cetera. | |
1188 | ||
1189 | First make sure there is a pending SIGSTOP. Since we are | |
1190 | already attached, the process can not transition from stopped | |
1191 | to running without a PTRACE_CONT; so we know this signal will | |
1192 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1193 | probably already in the queue (unless this kernel is old | |
1194 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1195 | is not an RT signal, it can only be queued once. */ | |
1196 | kill_lwp (pid, SIGSTOP); | |
1197 | ||
1198 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1199 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1200 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1201 | } | |
1202 | ||
1203 | /* Make sure the initial process is stopped. The user-level threads | |
1204 | layer might want to poke around in the inferior, and that won't | |
1205 | work if things haven't stabilized yet. */ | |
1206 | new_pid = my_waitpid (pid, &status, 0); | |
1207 | if (new_pid == -1 && errno == ECHILD) | |
1208 | { | |
1209 | if (first) | |
1210 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1211 | ||
1212 | /* Try again with __WCLONE to check cloned processes. */ | |
1213 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1214 | *cloned = 1; | |
1215 | } | |
1216 | ||
1217 | gdb_assert (pid == new_pid && WIFSTOPPED (status)); | |
1218 | ||
1219 | if (WSTOPSIG (status) != SIGSTOP) | |
1220 | { | |
1221 | *signalled = 1; | |
1222 | if (debug_linux_nat) | |
1223 | fprintf_unfiltered (gdb_stdlog, | |
1224 | "LNPAW: Received %s after attaching\n", | |
1225 | status_to_str (status)); | |
1226 | } | |
1227 | ||
1228 | return status; | |
1229 | } | |
1230 | ||
1231 | /* Attach to the LWP specified by PID. Return 0 if successful or -1 | |
1232 | if the new LWP could not be attached. */ | |
d6b0e80f | 1233 | |
9ee57c33 | 1234 | int |
93815fbf | 1235 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1236 | { |
9ee57c33 | 1237 | struct lwp_info *lp; |
84e46146 | 1238 | enum sigchld_state async_events_original_state; |
d6b0e80f AC |
1239 | |
1240 | gdb_assert (is_lwp (ptid)); | |
1241 | ||
84e46146 | 1242 | async_events_original_state = linux_nat_async_events (sigchld_sync); |
d6b0e80f | 1243 | |
9ee57c33 | 1244 | lp = find_lwp_pid (ptid); |
d6b0e80f AC |
1245 | |
1246 | /* We assume that we're already attached to any LWP that has an id | |
1247 | equal to the overall process id, and to any LWP that is already | |
1248 | in our list of LWPs. If we're not seeing exit events from threads | |
1249 | and we've had PID wraparound since we last tried to stop all threads, | |
1250 | this assumption might be wrong; fortunately, this is very unlikely | |
1251 | to happen. */ | |
9ee57c33 | 1252 | if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL) |
d6b0e80f | 1253 | { |
a0ef4274 | 1254 | int status, cloned = 0, signalled = 0; |
d6b0e80f AC |
1255 | |
1256 | if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0) | |
9ee57c33 DJ |
1257 | { |
1258 | /* If we fail to attach to the thread, issue a warning, | |
1259 | but continue. One way this can happen is if thread | |
e9efe249 | 1260 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1261 | bug may place threads in the thread list and then fail |
1262 | to create them. */ | |
1263 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1264 | safe_strerror (errno)); | |
1265 | return -1; | |
1266 | } | |
1267 | ||
d6b0e80f AC |
1268 | if (debug_linux_nat) |
1269 | fprintf_unfiltered (gdb_stdlog, | |
1270 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1271 | target_pid_to_str (ptid)); | |
1272 | ||
a0ef4274 DJ |
1273 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
1274 | lp = add_lwp (ptid); | |
1275 | lp->stopped = 1; | |
1276 | lp->cloned = cloned; | |
1277 | lp->signalled = signalled; | |
1278 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1279 | { |
a0ef4274 DJ |
1280 | lp->resumed = 1; |
1281 | lp->status = status; | |
d6b0e80f AC |
1282 | } |
1283 | ||
a0ef4274 | 1284 | target_post_attach (GET_LWP (lp->ptid)); |
d6b0e80f AC |
1285 | |
1286 | if (debug_linux_nat) | |
1287 | { | |
1288 | fprintf_unfiltered (gdb_stdlog, | |
1289 | "LLAL: waitpid %s received %s\n", | |
1290 | target_pid_to_str (ptid), | |
1291 | status_to_str (status)); | |
1292 | } | |
1293 | } | |
1294 | else | |
1295 | { | |
1296 | /* We assume that the LWP representing the original process is | |
1297 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1298 | that the GNU/linux ptrace layer uses to keep track of |
1299 | threads. Note that this won't have already been done since | |
1300 | the main thread will have, we assume, been stopped by an | |
1301 | attach from a different layer. */ | |
9ee57c33 DJ |
1302 | if (lp == NULL) |
1303 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1304 | lp->stopped = 1; |
1305 | } | |
9ee57c33 | 1306 | |
84e46146 | 1307 | linux_nat_async_events (async_events_original_state); |
9ee57c33 | 1308 | return 0; |
d6b0e80f AC |
1309 | } |
1310 | ||
b84876c2 PA |
1311 | static void |
1312 | linux_nat_create_inferior (char *exec_file, char *allargs, char **env, | |
1313 | int from_tty) | |
1314 | { | |
1315 | int saved_async = 0; | |
10568435 JK |
1316 | #ifdef HAVE_PERSONALITY |
1317 | int personality_orig = 0, personality_set = 0; | |
1318 | #endif /* HAVE_PERSONALITY */ | |
b84876c2 PA |
1319 | |
1320 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1321 | we have to mask the async mode. */ | |
1322 | ||
1323 | if (target_can_async_p ()) | |
84e46146 PA |
1324 | /* Mask async mode. Creating a child requires a loop calling |
1325 | wait_for_inferior currently. */ | |
b84876c2 PA |
1326 | saved_async = linux_nat_async_mask (0); |
1327 | else | |
1328 | { | |
1329 | /* Restore the original signal mask. */ | |
1330 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1331 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1332 | suspend_mask = normal_mask; | |
1333 | sigdelset (&suspend_mask, SIGCHLD); | |
1334 | } | |
1335 | ||
84e46146 PA |
1336 | /* Set SIGCHLD to the default action, until after execing the child, |
1337 | since the inferior inherits the superior's signal mask. It will | |
1338 | be blocked again in linux_nat_wait, which is only reached after | |
1339 | the inferior execing. */ | |
1340 | linux_nat_async_events (sigchld_default); | |
1341 | ||
10568435 JK |
1342 | #ifdef HAVE_PERSONALITY |
1343 | if (disable_randomization) | |
1344 | { | |
1345 | errno = 0; | |
1346 | personality_orig = personality (0xffffffff); | |
1347 | if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE)) | |
1348 | { | |
1349 | personality_set = 1; | |
1350 | personality (personality_orig | ADDR_NO_RANDOMIZE); | |
1351 | } | |
1352 | if (errno != 0 || (personality_set | |
1353 | && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE))) | |
1354 | warning (_("Error disabling address space randomization: %s"), | |
1355 | safe_strerror (errno)); | |
1356 | } | |
1357 | #endif /* HAVE_PERSONALITY */ | |
1358 | ||
b84876c2 PA |
1359 | linux_ops->to_create_inferior (exec_file, allargs, env, from_tty); |
1360 | ||
10568435 JK |
1361 | #ifdef HAVE_PERSONALITY |
1362 | if (personality_set) | |
1363 | { | |
1364 | errno = 0; | |
1365 | personality (personality_orig); | |
1366 | if (errno != 0) | |
1367 | warning (_("Error restoring address space randomization: %s"), | |
1368 | safe_strerror (errno)); | |
1369 | } | |
1370 | #endif /* HAVE_PERSONALITY */ | |
1371 | ||
b84876c2 PA |
1372 | if (saved_async) |
1373 | linux_nat_async_mask (saved_async); | |
1374 | } | |
1375 | ||
d6b0e80f AC |
1376 | static void |
1377 | linux_nat_attach (char *args, int from_tty) | |
1378 | { | |
1379 | struct lwp_info *lp; | |
d6b0e80f AC |
1380 | int status; |
1381 | ||
1382 | /* FIXME: We should probably accept a list of process id's, and | |
1383 | attach all of them. */ | |
10d6c8cd | 1384 | linux_ops->to_attach (args, from_tty); |
d6b0e80f | 1385 | |
b84876c2 PA |
1386 | if (!target_can_async_p ()) |
1387 | { | |
1388 | /* Restore the original signal mask. */ | |
1389 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1390 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1391 | suspend_mask = normal_mask; | |
1392 | sigdelset (&suspend_mask, SIGCHLD); | |
1393 | } | |
1394 | ||
9f0bdab8 DJ |
1395 | /* Add the initial process as the first LWP to the list. */ |
1396 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid)); | |
1397 | lp = add_lwp (inferior_ptid); | |
a0ef4274 DJ |
1398 | |
1399 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1400 | &lp->signalled); | |
1401 | lp->stopped = 1; | |
9f0bdab8 | 1402 | |
403fe197 PA |
1403 | /* If this process is not using thread_db, then we still don't |
1404 | detect any other threads, but add at least this one. */ | |
1405 | add_thread_silent (lp->ptid); | |
1406 | ||
a0ef4274 | 1407 | /* Save the wait status to report later. */ |
d6b0e80f | 1408 | lp->resumed = 1; |
a0ef4274 DJ |
1409 | if (debug_linux_nat) |
1410 | fprintf_unfiltered (gdb_stdlog, | |
1411 | "LNA: waitpid %ld, saving status %s\n", | |
1412 | (long) GET_PID (lp->ptid), status_to_str (status)); | |
710151dd PA |
1413 | |
1414 | if (!target_can_async_p ()) | |
a0ef4274 | 1415 | lp->status = status; |
710151dd PA |
1416 | else |
1417 | { | |
1418 | /* We already waited for this LWP, so put the wait result on the | |
1419 | pipe. The event loop will wake up and gets us to handling | |
1420 | this event. */ | |
a0ef4274 DJ |
1421 | linux_nat_event_pipe_push (GET_PID (lp->ptid), status, |
1422 | lp->cloned ? __WCLONE : 0); | |
b84876c2 PA |
1423 | /* Register in the event loop. */ |
1424 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1425 | } |
1426 | } | |
1427 | ||
a0ef4274 DJ |
1428 | /* Get pending status of LP. */ |
1429 | static int | |
1430 | get_pending_status (struct lwp_info *lp, int *status) | |
1431 | { | |
1432 | struct target_waitstatus last; | |
1433 | ptid_t last_ptid; | |
1434 | ||
1435 | get_last_target_status (&last_ptid, &last); | |
1436 | ||
1437 | /* If this lwp is the ptid that GDB is processing an event from, the | |
1438 | signal will be in stop_signal. Otherwise, in all-stop + sync | |
1439 | mode, we may cache pending events in lp->status while trying to | |
1440 | stop all threads (see stop_wait_callback). In async mode, the | |
1441 | events are always cached in waitpid_queue. */ | |
1442 | ||
1443 | *status = 0; | |
1444 | if (GET_LWP (lp->ptid) == GET_LWP (last_ptid)) | |
1445 | { | |
1446 | if (stop_signal != TARGET_SIGNAL_0 | |
1447 | && signal_pass_state (stop_signal)) | |
1448 | *status = W_STOPCODE (target_signal_to_host (stop_signal)); | |
1449 | } | |
1450 | else if (target_can_async_p ()) | |
1451 | queued_waitpid (GET_LWP (lp->ptid), status, __WALL); | |
1452 | else | |
1453 | *status = lp->status; | |
1454 | ||
1455 | return 0; | |
1456 | } | |
1457 | ||
d6b0e80f AC |
1458 | static int |
1459 | detach_callback (struct lwp_info *lp, void *data) | |
1460 | { | |
1461 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1462 | ||
1463 | if (debug_linux_nat && lp->status) | |
1464 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1465 | strsignal (WSTOPSIG (lp->status)), | |
1466 | target_pid_to_str (lp->ptid)); | |
1467 | ||
a0ef4274 DJ |
1468 | /* If there is a pending SIGSTOP, get rid of it. */ |
1469 | if (lp->signalled) | |
d6b0e80f | 1470 | { |
d6b0e80f AC |
1471 | if (debug_linux_nat) |
1472 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1473 | "DC: Sending SIGCONT to %s\n", |
1474 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1475 | |
a0ef4274 | 1476 | kill_lwp (GET_LWP (lp->ptid), SIGCONT); |
d6b0e80f | 1477 | lp->signalled = 0; |
d6b0e80f AC |
1478 | } |
1479 | ||
1480 | /* We don't actually detach from the LWP that has an id equal to the | |
1481 | overall process id just yet. */ | |
1482 | if (GET_LWP (lp->ptid) != GET_PID (lp->ptid)) | |
1483 | { | |
a0ef4274 DJ |
1484 | int status = 0; |
1485 | ||
1486 | /* Pass on any pending signal for this LWP. */ | |
1487 | get_pending_status (lp, &status); | |
1488 | ||
d6b0e80f AC |
1489 | errno = 0; |
1490 | if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0, | |
a0ef4274 | 1491 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1492 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1493 | safe_strerror (errno)); |
1494 | ||
1495 | if (debug_linux_nat) | |
1496 | fprintf_unfiltered (gdb_stdlog, | |
1497 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1498 | target_pid_to_str (lp->ptid), | |
1499 | strsignal (WSTOPSIG (lp->status))); | |
1500 | ||
1501 | delete_lwp (lp->ptid); | |
1502 | } | |
1503 | ||
1504 | return 0; | |
1505 | } | |
1506 | ||
1507 | static void | |
1508 | linux_nat_detach (char *args, int from_tty) | |
1509 | { | |
b84876c2 | 1510 | int pid; |
a0ef4274 DJ |
1511 | int status; |
1512 | enum target_signal sig; | |
1513 | ||
b84876c2 PA |
1514 | if (target_can_async_p ()) |
1515 | linux_nat_async (NULL, 0); | |
1516 | ||
d6b0e80f AC |
1517 | iterate_over_lwps (detach_callback, NULL); |
1518 | ||
1519 | /* Only the initial process should be left right now. */ | |
1520 | gdb_assert (num_lwps == 1); | |
1521 | ||
a0ef4274 DJ |
1522 | /* Pass on any pending signal for the last LWP. */ |
1523 | if ((args == NULL || *args == '\0') | |
1524 | && get_pending_status (lwp_list, &status) != -1 | |
1525 | && WIFSTOPPED (status)) | |
1526 | { | |
1527 | /* Put the signal number in ARGS so that inf_ptrace_detach will | |
1528 | pass it along with PTRACE_DETACH. */ | |
1529 | args = alloca (8); | |
1530 | sprintf (args, "%d", (int) WSTOPSIG (status)); | |
1531 | fprintf_unfiltered (gdb_stdlog, | |
1532 | "LND: Sending signal %s to %s\n", | |
1533 | args, | |
1534 | target_pid_to_str (lwp_list->ptid)); | |
1535 | } | |
1536 | ||
d6b0e80f AC |
1537 | /* Destroy LWP info; it's no longer valid. */ |
1538 | init_lwp_list (); | |
1539 | ||
b84876c2 PA |
1540 | pid = GET_PID (inferior_ptid); |
1541 | inferior_ptid = pid_to_ptid (pid); | |
10d6c8cd | 1542 | linux_ops->to_detach (args, from_tty); |
b84876c2 PA |
1543 | |
1544 | if (target_can_async_p ()) | |
1545 | drain_queued_events (pid); | |
d6b0e80f AC |
1546 | } |
1547 | ||
1548 | /* Resume LP. */ | |
1549 | ||
1550 | static int | |
1551 | resume_callback (struct lwp_info *lp, void *data) | |
1552 | { | |
1553 | if (lp->stopped && lp->status == 0) | |
1554 | { | |
10d6c8cd DJ |
1555 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
1556 | 0, TARGET_SIGNAL_0); | |
d6b0e80f AC |
1557 | if (debug_linux_nat) |
1558 | fprintf_unfiltered (gdb_stdlog, | |
1559 | "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n", | |
1560 | target_pid_to_str (lp->ptid)); | |
1561 | lp->stopped = 0; | |
1562 | lp->step = 0; | |
9f0bdab8 | 1563 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
d6b0e80f AC |
1564 | } |
1565 | ||
1566 | return 0; | |
1567 | } | |
1568 | ||
1569 | static int | |
1570 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1571 | { | |
1572 | lp->resumed = 0; | |
1573 | return 0; | |
1574 | } | |
1575 | ||
1576 | static int | |
1577 | resume_set_callback (struct lwp_info *lp, void *data) | |
1578 | { | |
1579 | lp->resumed = 1; | |
1580 | return 0; | |
1581 | } | |
1582 | ||
1583 | static void | |
1584 | linux_nat_resume (ptid_t ptid, int step, enum target_signal signo) | |
1585 | { | |
1586 | struct lwp_info *lp; | |
1587 | int resume_all; | |
1588 | ||
76f50ad1 DJ |
1589 | if (debug_linux_nat) |
1590 | fprintf_unfiltered (gdb_stdlog, | |
1591 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1592 | step ? "step" : "resume", | |
1593 | target_pid_to_str (ptid), | |
1594 | signo ? strsignal (signo) : "0", | |
1595 | target_pid_to_str (inferior_ptid)); | |
1596 | ||
e26af52f DJ |
1597 | prune_lwps (); |
1598 | ||
b84876c2 PA |
1599 | if (target_can_async_p ()) |
1600 | /* Block events while we're here. */ | |
84e46146 | 1601 | linux_nat_async_events (sigchld_sync); |
b84876c2 | 1602 | |
d6b0e80f AC |
1603 | /* A specific PTID means `step only this process id'. */ |
1604 | resume_all = (PIDGET (ptid) == -1); | |
1605 | ||
1606 | if (resume_all) | |
1607 | iterate_over_lwps (resume_set_callback, NULL); | |
1608 | else | |
1609 | iterate_over_lwps (resume_clear_callback, NULL); | |
1610 | ||
1611 | /* If PID is -1, it's the current inferior that should be | |
1612 | handled specially. */ | |
1613 | if (PIDGET (ptid) == -1) | |
1614 | ptid = inferior_ptid; | |
1615 | ||
1616 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1617 | gdb_assert (lp != NULL); |
d6b0e80f | 1618 | |
9f0bdab8 | 1619 | ptid = pid_to_ptid (GET_LWP (lp->ptid)); |
d6b0e80f | 1620 | |
9f0bdab8 DJ |
1621 | /* Remember if we're stepping. */ |
1622 | lp->step = step; | |
d6b0e80f | 1623 | |
9f0bdab8 DJ |
1624 | /* Mark this LWP as resumed. */ |
1625 | lp->resumed = 1; | |
76f50ad1 | 1626 | |
9f0bdab8 DJ |
1627 | /* If we have a pending wait status for this thread, there is no |
1628 | point in resuming the process. But first make sure that | |
1629 | linux_nat_wait won't preemptively handle the event - we | |
1630 | should never take this short-circuit if we are going to | |
1631 | leave LP running, since we have skipped resuming all the | |
1632 | other threads. This bit of code needs to be synchronized | |
1633 | with linux_nat_wait. */ | |
76f50ad1 | 1634 | |
710151dd PA |
1635 | /* In async mode, we never have pending wait status. */ |
1636 | if (target_can_async_p () && lp->status) | |
1637 | internal_error (__FILE__, __LINE__, "Pending status in async mode"); | |
1638 | ||
9f0bdab8 DJ |
1639 | if (lp->status && WIFSTOPPED (lp->status)) |
1640 | { | |
1641 | int saved_signo = target_signal_from_host (WSTOPSIG (lp->status)); | |
76f50ad1 | 1642 | |
9f0bdab8 DJ |
1643 | if (signal_stop_state (saved_signo) == 0 |
1644 | && signal_print_state (saved_signo) == 0 | |
1645 | && signal_pass_state (saved_signo) == 1) | |
d6b0e80f | 1646 | { |
9f0bdab8 DJ |
1647 | if (debug_linux_nat) |
1648 | fprintf_unfiltered (gdb_stdlog, | |
1649 | "LLR: Not short circuiting for ignored " | |
1650 | "status 0x%x\n", lp->status); | |
1651 | ||
d6b0e80f AC |
1652 | /* FIXME: What should we do if we are supposed to continue |
1653 | this thread with a signal? */ | |
1654 | gdb_assert (signo == TARGET_SIGNAL_0); | |
9f0bdab8 DJ |
1655 | signo = saved_signo; |
1656 | lp->status = 0; | |
1657 | } | |
1658 | } | |
76f50ad1 | 1659 | |
9f0bdab8 DJ |
1660 | if (lp->status) |
1661 | { | |
1662 | /* FIXME: What should we do if we are supposed to continue | |
1663 | this thread with a signal? */ | |
1664 | gdb_assert (signo == TARGET_SIGNAL_0); | |
76f50ad1 | 1665 | |
9f0bdab8 DJ |
1666 | if (debug_linux_nat) |
1667 | fprintf_unfiltered (gdb_stdlog, | |
1668 | "LLR: Short circuiting for status 0x%x\n", | |
1669 | lp->status); | |
d6b0e80f | 1670 | |
9f0bdab8 | 1671 | return; |
d6b0e80f AC |
1672 | } |
1673 | ||
9f0bdab8 DJ |
1674 | /* Mark LWP as not stopped to prevent it from being continued by |
1675 | resume_callback. */ | |
1676 | lp->stopped = 0; | |
1677 | ||
d6b0e80f AC |
1678 | if (resume_all) |
1679 | iterate_over_lwps (resume_callback, NULL); | |
1680 | ||
10d6c8cd | 1681 | linux_ops->to_resume (ptid, step, signo); |
9f0bdab8 DJ |
1682 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
1683 | ||
d6b0e80f AC |
1684 | if (debug_linux_nat) |
1685 | fprintf_unfiltered (gdb_stdlog, | |
1686 | "LLR: %s %s, %s (resume event thread)\n", | |
1687 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1688 | target_pid_to_str (ptid), | |
1689 | signo ? strsignal (signo) : "0"); | |
b84876c2 PA |
1690 | |
1691 | if (target_can_async_p ()) | |
8ea051c5 | 1692 | target_async (inferior_event_handler, 0); |
d6b0e80f AC |
1693 | } |
1694 | ||
1695 | /* Issue kill to specified lwp. */ | |
1696 | ||
1697 | static int tkill_failed; | |
1698 | ||
1699 | static int | |
1700 | kill_lwp (int lwpid, int signo) | |
1701 | { | |
1702 | errno = 0; | |
1703 | ||
1704 | /* Use tkill, if possible, in case we are using nptl threads. If tkill | |
1705 | fails, then we are not using nptl threads and we should be using kill. */ | |
1706 | ||
1707 | #ifdef HAVE_TKILL_SYSCALL | |
1708 | if (!tkill_failed) | |
1709 | { | |
1710 | int ret = syscall (__NR_tkill, lwpid, signo); | |
1711 | if (errno != ENOSYS) | |
1712 | return ret; | |
1713 | errno = 0; | |
1714 | tkill_failed = 1; | |
1715 | } | |
1716 | #endif | |
1717 | ||
1718 | return kill (lwpid, signo); | |
1719 | } | |
1720 | ||
3d799a95 DJ |
1721 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1722 | event, we need to add the new LWP to our list (and not report the | |
1723 | trap to higher layers). This function returns non-zero if the | |
1724 | event should be ignored and we should wait again. If STOPPING is | |
1725 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1726 | |
1727 | static int | |
3d799a95 DJ |
1728 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1729 | int stopping) | |
d6b0e80f | 1730 | { |
3d799a95 DJ |
1731 | int pid = GET_LWP (lp->ptid); |
1732 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1733 | struct lwp_info *new_lp = NULL; | |
1734 | int event = status >> 16; | |
d6b0e80f | 1735 | |
3d799a95 DJ |
1736 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1737 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1738 | { |
3d799a95 DJ |
1739 | unsigned long new_pid; |
1740 | int ret; | |
1741 | ||
1742 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1743 | |
3d799a95 DJ |
1744 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1745 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1746 | { | |
1747 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1748 | hits the SIGSTOP, but we're already attached. */ | |
1749 | ret = my_waitpid (new_pid, &status, | |
1750 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
1751 | if (ret == -1) | |
1752 | perror_with_name (_("waiting for new child")); | |
1753 | else if (ret != new_pid) | |
1754 | internal_error (__FILE__, __LINE__, | |
1755 | _("wait returned unexpected PID %d"), ret); | |
1756 | else if (!WIFSTOPPED (status)) | |
1757 | internal_error (__FILE__, __LINE__, | |
1758 | _("wait returned unexpected status 0x%x"), status); | |
1759 | } | |
1760 | ||
3a3e9ee3 | 1761 | ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0); |
3d799a95 DJ |
1762 | |
1763 | if (event == PTRACE_EVENT_FORK) | |
1764 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
1765 | else if (event == PTRACE_EVENT_VFORK) | |
1766 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 1767 | else |
3d799a95 DJ |
1768 | { |
1769 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
1770 | new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid))); | |
1771 | new_lp->cloned = 1; | |
d6b0e80f | 1772 | |
3d799a95 DJ |
1773 | if (WSTOPSIG (status) != SIGSTOP) |
1774 | { | |
1775 | /* This can happen if someone starts sending signals to | |
1776 | the new thread before it gets a chance to run, which | |
1777 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
1778 | This is an unlikely case, and harder to handle for | |
1779 | fork / vfork than for clone, so we do not try - but | |
1780 | we handle it for clone events here. We'll send | |
1781 | the other signal on to the thread below. */ | |
1782 | ||
1783 | new_lp->signalled = 1; | |
1784 | } | |
1785 | else | |
1786 | status = 0; | |
d6b0e80f | 1787 | |
3d799a95 DJ |
1788 | if (stopping) |
1789 | new_lp->stopped = 1; | |
1790 | else | |
1791 | { | |
1792 | new_lp->resumed = 1; | |
3a3e9ee3 PA |
1793 | ptrace (PTRACE_CONT, |
1794 | PIDGET (lp->waitstatus.value.related_pid), 0, | |
3d799a95 DJ |
1795 | status ? WSTOPSIG (status) : 0); |
1796 | } | |
d6b0e80f | 1797 | |
3d799a95 DJ |
1798 | if (debug_linux_nat) |
1799 | fprintf_unfiltered (gdb_stdlog, | |
1800 | "LHEW: Got clone event from LWP %ld, resuming\n", | |
1801 | GET_LWP (lp->ptid)); | |
1802 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1803 | ||
1804 | return 1; | |
1805 | } | |
1806 | ||
1807 | return 0; | |
d6b0e80f AC |
1808 | } |
1809 | ||
3d799a95 DJ |
1810 | if (event == PTRACE_EVENT_EXEC) |
1811 | { | |
1812 | ourstatus->kind = TARGET_WAITKIND_EXECD; | |
1813 | ourstatus->value.execd_pathname | |
6d8fd2b7 | 1814 | = xstrdup (linux_child_pid_to_exec_file (pid)); |
3d799a95 DJ |
1815 | |
1816 | if (linux_parent_pid) | |
1817 | { | |
1818 | detach_breakpoints (linux_parent_pid); | |
1819 | ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0); | |
1820 | ||
1821 | linux_parent_pid = 0; | |
1822 | } | |
1823 | ||
25b22b0a PA |
1824 | /* At this point, all inserted breakpoints are gone. Doing this |
1825 | as soon as we detect an exec prevents the badness of deleting | |
1826 | a breakpoint writing the current "shadow contents" to lift | |
1827 | the bp. That shadow is NOT valid after an exec. | |
1828 | ||
1829 | Note that we have to do this after the detach_breakpoints | |
1830 | call above, otherwise breakpoints wouldn't be lifted from the | |
1831 | parent on a vfork, because detach_breakpoints would think | |
1832 | that breakpoints are not inserted. */ | |
1833 | mark_breakpoints_out (); | |
3d799a95 DJ |
1834 | return 0; |
1835 | } | |
1836 | ||
1837 | internal_error (__FILE__, __LINE__, | |
1838 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
1839 | } |
1840 | ||
1841 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
1842 | exited. */ | |
1843 | ||
1844 | static int | |
1845 | wait_lwp (struct lwp_info *lp) | |
1846 | { | |
1847 | pid_t pid; | |
1848 | int status; | |
1849 | int thread_dead = 0; | |
1850 | ||
1851 | gdb_assert (!lp->stopped); | |
1852 | gdb_assert (lp->status == 0); | |
1853 | ||
58aecb61 | 1854 | pid = my_waitpid (GET_LWP (lp->ptid), &status, 0); |
d6b0e80f AC |
1855 | if (pid == -1 && errno == ECHILD) |
1856 | { | |
58aecb61 | 1857 | pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE); |
d6b0e80f AC |
1858 | if (pid == -1 && errno == ECHILD) |
1859 | { | |
1860 | /* The thread has previously exited. We need to delete it | |
1861 | now because, for some vendor 2.4 kernels with NPTL | |
1862 | support backported, there won't be an exit event unless | |
1863 | it is the main thread. 2.6 kernels will report an exit | |
1864 | event for each thread that exits, as expected. */ | |
1865 | thread_dead = 1; | |
1866 | if (debug_linux_nat) | |
1867 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
1868 | target_pid_to_str (lp->ptid)); | |
1869 | } | |
1870 | } | |
1871 | ||
1872 | if (!thread_dead) | |
1873 | { | |
1874 | gdb_assert (pid == GET_LWP (lp->ptid)); | |
1875 | ||
1876 | if (debug_linux_nat) | |
1877 | { | |
1878 | fprintf_unfiltered (gdb_stdlog, | |
1879 | "WL: waitpid %s received %s\n", | |
1880 | target_pid_to_str (lp->ptid), | |
1881 | status_to_str (status)); | |
1882 | } | |
1883 | } | |
1884 | ||
1885 | /* Check if the thread has exited. */ | |
1886 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
1887 | { | |
1888 | thread_dead = 1; | |
1889 | if (debug_linux_nat) | |
1890 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
1891 | target_pid_to_str (lp->ptid)); | |
1892 | } | |
1893 | ||
1894 | if (thread_dead) | |
1895 | { | |
e26af52f | 1896 | exit_lwp (lp); |
d6b0e80f AC |
1897 | return 0; |
1898 | } | |
1899 | ||
1900 | gdb_assert (WIFSTOPPED (status)); | |
1901 | ||
1902 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
1903 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
1904 | { | |
1905 | if (debug_linux_nat) | |
1906 | fprintf_unfiltered (gdb_stdlog, | |
1907 | "WL: Handling extended status 0x%06x\n", | |
1908 | status); | |
3d799a95 | 1909 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
1910 | return wait_lwp (lp); |
1911 | } | |
1912 | ||
1913 | return status; | |
1914 | } | |
1915 | ||
9f0bdab8 DJ |
1916 | /* Save the most recent siginfo for LP. This is currently only called |
1917 | for SIGTRAP; some ports use the si_addr field for | |
1918 | target_stopped_data_address. In the future, it may also be used to | |
1919 | restore the siginfo of requeued signals. */ | |
1920 | ||
1921 | static void | |
1922 | save_siginfo (struct lwp_info *lp) | |
1923 | { | |
1924 | errno = 0; | |
1925 | ptrace (PTRACE_GETSIGINFO, GET_LWP (lp->ptid), | |
1926 | (PTRACE_TYPE_ARG3) 0, &lp->siginfo); | |
1927 | ||
1928 | if (errno != 0) | |
1929 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); | |
1930 | } | |
1931 | ||
d6b0e80f AC |
1932 | /* Send a SIGSTOP to LP. */ |
1933 | ||
1934 | static int | |
1935 | stop_callback (struct lwp_info *lp, void *data) | |
1936 | { | |
1937 | if (!lp->stopped && !lp->signalled) | |
1938 | { | |
1939 | int ret; | |
1940 | ||
1941 | if (debug_linux_nat) | |
1942 | { | |
1943 | fprintf_unfiltered (gdb_stdlog, | |
1944 | "SC: kill %s **<SIGSTOP>**\n", | |
1945 | target_pid_to_str (lp->ptid)); | |
1946 | } | |
1947 | errno = 0; | |
1948 | ret = kill_lwp (GET_LWP (lp->ptid), SIGSTOP); | |
1949 | if (debug_linux_nat) | |
1950 | { | |
1951 | fprintf_unfiltered (gdb_stdlog, | |
1952 | "SC: lwp kill %d %s\n", | |
1953 | ret, | |
1954 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
1955 | } | |
1956 | ||
1957 | lp->signalled = 1; | |
1958 | gdb_assert (lp->status == 0); | |
1959 | } | |
1960 | ||
1961 | return 0; | |
1962 | } | |
1963 | ||
1964 | /* Wait until LP is stopped. If DATA is non-null it is interpreted as | |
1965 | a pointer to a set of signals to be flushed immediately. */ | |
1966 | ||
1967 | static int | |
1968 | stop_wait_callback (struct lwp_info *lp, void *data) | |
1969 | { | |
1970 | sigset_t *flush_mask = data; | |
1971 | ||
1972 | if (!lp->stopped) | |
1973 | { | |
1974 | int status; | |
1975 | ||
1976 | status = wait_lwp (lp); | |
1977 | if (status == 0) | |
1978 | return 0; | |
1979 | ||
1980 | /* Ignore any signals in FLUSH_MASK. */ | |
1981 | if (flush_mask && sigismember (flush_mask, WSTOPSIG (status))) | |
1982 | { | |
1983 | if (!lp->signalled) | |
1984 | { | |
1985 | lp->stopped = 1; | |
1986 | return 0; | |
1987 | } | |
1988 | ||
1989 | errno = 0; | |
1990 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1991 | if (debug_linux_nat) | |
1992 | fprintf_unfiltered (gdb_stdlog, | |
1993 | "PTRACE_CONT %s, 0, 0 (%s)\n", | |
1994 | target_pid_to_str (lp->ptid), | |
1995 | errno ? safe_strerror (errno) : "OK"); | |
1996 | ||
1997 | return stop_wait_callback (lp, flush_mask); | |
1998 | } | |
1999 | ||
2000 | if (WSTOPSIG (status) != SIGSTOP) | |
2001 | { | |
2002 | if (WSTOPSIG (status) == SIGTRAP) | |
2003 | { | |
2004 | /* If a LWP other than the LWP that we're reporting an | |
2005 | event for has hit a GDB breakpoint (as opposed to | |
2006 | some random trap signal), then just arrange for it to | |
2007 | hit it again later. We don't keep the SIGTRAP status | |
2008 | and don't forward the SIGTRAP signal to the LWP. We | |
2009 | will handle the current event, eventually we will | |
2010 | resume all LWPs, and this one will get its breakpoint | |
2011 | trap again. | |
2012 | ||
2013 | If we do not do this, then we run the risk that the | |
2014 | user will delete or disable the breakpoint, but the | |
2015 | thread will have already tripped on it. */ | |
2016 | ||
9f0bdab8 DJ |
2017 | /* Save the trap's siginfo in case we need it later. */ |
2018 | save_siginfo (lp); | |
2019 | ||
d6b0e80f AC |
2020 | /* Now resume this LWP and get the SIGSTOP event. */ |
2021 | errno = 0; | |
2022 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2023 | if (debug_linux_nat) | |
2024 | { | |
2025 | fprintf_unfiltered (gdb_stdlog, | |
2026 | "PTRACE_CONT %s, 0, 0 (%s)\n", | |
2027 | target_pid_to_str (lp->ptid), | |
2028 | errno ? safe_strerror (errno) : "OK"); | |
2029 | ||
2030 | fprintf_unfiltered (gdb_stdlog, | |
2031 | "SWC: Candidate SIGTRAP event in %s\n", | |
2032 | target_pid_to_str (lp->ptid)); | |
2033 | } | |
710151dd PA |
2034 | /* Hold this event/waitstatus while we check to see if |
2035 | there are any more (we still want to get that SIGSTOP). */ | |
d6b0e80f | 2036 | stop_wait_callback (lp, data); |
710151dd PA |
2037 | |
2038 | if (target_can_async_p ()) | |
d6b0e80f | 2039 | { |
710151dd PA |
2040 | /* Don't leave a pending wait status in async mode. |
2041 | Retrigger the breakpoint. */ | |
2042 | if (!cancel_breakpoint (lp)) | |
d6b0e80f | 2043 | { |
710151dd PA |
2044 | /* There was no gdb breakpoint set at pc. Put |
2045 | the event back in the queue. */ | |
2046 | if (debug_linux_nat) | |
2047 | fprintf_unfiltered (gdb_stdlog, | |
2048 | "SWC: kill %s, %s\n", | |
2049 | target_pid_to_str (lp->ptid), | |
2050 | status_to_str ((int) status)); | |
2051 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
2052 | } | |
2053 | } | |
2054 | else | |
2055 | { | |
2056 | /* Hold the SIGTRAP for handling by | |
2057 | linux_nat_wait. */ | |
2058 | /* If there's another event, throw it back into the | |
2059 | queue. */ | |
2060 | if (lp->status) | |
2061 | { | |
2062 | if (debug_linux_nat) | |
2063 | fprintf_unfiltered (gdb_stdlog, | |
2064 | "SWC: kill %s, %s\n", | |
2065 | target_pid_to_str (lp->ptid), | |
2066 | status_to_str ((int) status)); | |
2067 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status)); | |
d6b0e80f | 2068 | } |
710151dd PA |
2069 | /* Save the sigtrap event. */ |
2070 | lp->status = status; | |
d6b0e80f | 2071 | } |
d6b0e80f AC |
2072 | return 0; |
2073 | } | |
2074 | else | |
2075 | { | |
2076 | /* The thread was stopped with a signal other than | |
2077 | SIGSTOP, and didn't accidentally trip a breakpoint. */ | |
2078 | ||
2079 | if (debug_linux_nat) | |
2080 | { | |
2081 | fprintf_unfiltered (gdb_stdlog, | |
2082 | "SWC: Pending event %s in %s\n", | |
2083 | status_to_str ((int) status), | |
2084 | target_pid_to_str (lp->ptid)); | |
2085 | } | |
2086 | /* Now resume this LWP and get the SIGSTOP event. */ | |
2087 | errno = 0; | |
2088 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2089 | if (debug_linux_nat) | |
2090 | fprintf_unfiltered (gdb_stdlog, | |
2091 | "SWC: PTRACE_CONT %s, 0, 0 (%s)\n", | |
2092 | target_pid_to_str (lp->ptid), | |
2093 | errno ? safe_strerror (errno) : "OK"); | |
2094 | ||
2095 | /* Hold this event/waitstatus while we check to see if | |
2096 | there are any more (we still want to get that SIGSTOP). */ | |
2097 | stop_wait_callback (lp, data); | |
710151dd PA |
2098 | |
2099 | /* If the lp->status field is still empty, use it to | |
2100 | hold this event. If not, then this event must be | |
2101 | returned to the event queue of the LWP. */ | |
2102 | if (lp->status || target_can_async_p ()) | |
d6b0e80f AC |
2103 | { |
2104 | if (debug_linux_nat) | |
2105 | { | |
2106 | fprintf_unfiltered (gdb_stdlog, | |
2107 | "SWC: kill %s, %s\n", | |
2108 | target_pid_to_str (lp->ptid), | |
2109 | status_to_str ((int) status)); | |
2110 | } | |
2111 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
2112 | } | |
710151dd PA |
2113 | else |
2114 | lp->status = status; | |
d6b0e80f AC |
2115 | return 0; |
2116 | } | |
2117 | } | |
2118 | else | |
2119 | { | |
2120 | /* We caught the SIGSTOP that we intended to catch, so | |
2121 | there's no SIGSTOP pending. */ | |
2122 | lp->stopped = 1; | |
2123 | lp->signalled = 0; | |
2124 | } | |
2125 | } | |
2126 | ||
2127 | return 0; | |
2128 | } | |
2129 | ||
2130 | /* Check whether PID has any pending signals in FLUSH_MASK. If so set | |
2131 | the appropriate bits in PENDING, and return 1 - otherwise return 0. */ | |
2132 | ||
2133 | static int | |
2134 | linux_nat_has_pending (int pid, sigset_t *pending, sigset_t *flush_mask) | |
2135 | { | |
2136 | sigset_t blocked, ignored; | |
2137 | int i; | |
2138 | ||
2139 | linux_proc_pending_signals (pid, pending, &blocked, &ignored); | |
2140 | ||
2141 | if (!flush_mask) | |
2142 | return 0; | |
2143 | ||
2144 | for (i = 1; i < NSIG; i++) | |
2145 | if (sigismember (pending, i)) | |
2146 | if (!sigismember (flush_mask, i) | |
2147 | || sigismember (&blocked, i) | |
2148 | || sigismember (&ignored, i)) | |
2149 | sigdelset (pending, i); | |
2150 | ||
2151 | if (sigisemptyset (pending)) | |
2152 | return 0; | |
2153 | ||
2154 | return 1; | |
2155 | } | |
2156 | ||
2157 | /* DATA is interpreted as a mask of signals to flush. If LP has | |
2158 | signals pending, and they are all in the flush mask, then arrange | |
2159 | to flush them. LP should be stopped, as should all other threads | |
2160 | it might share a signal queue with. */ | |
2161 | ||
2162 | static int | |
2163 | flush_callback (struct lwp_info *lp, void *data) | |
2164 | { | |
2165 | sigset_t *flush_mask = data; | |
2166 | sigset_t pending, intersection, blocked, ignored; | |
2167 | int pid, status; | |
2168 | ||
2169 | /* Normally, when an LWP exits, it is removed from the LWP list. The | |
2170 | last LWP isn't removed till later, however. So if there is only | |
2171 | one LWP on the list, make sure it's alive. */ | |
2172 | if (lwp_list == lp && lp->next == NULL) | |
2173 | if (!linux_nat_thread_alive (lp->ptid)) | |
2174 | return 0; | |
2175 | ||
2176 | /* Just because the LWP is stopped doesn't mean that new signals | |
2177 | can't arrive from outside, so this function must be careful of | |
2178 | race conditions. However, because all threads are stopped, we | |
2179 | can assume that the pending mask will not shrink unless we resume | |
2180 | the LWP, and that it will then get another signal. We can't | |
2181 | control which one, however. */ | |
2182 | ||
2183 | if (lp->status) | |
2184 | { | |
2185 | if (debug_linux_nat) | |
a3f17187 | 2186 | printf_unfiltered (_("FC: LP has pending status %06x\n"), lp->status); |
d6b0e80f AC |
2187 | if (WIFSTOPPED (lp->status) && sigismember (flush_mask, WSTOPSIG (lp->status))) |
2188 | lp->status = 0; | |
2189 | } | |
2190 | ||
3d799a95 DJ |
2191 | /* While there is a pending signal we would like to flush, continue |
2192 | the inferior and collect another signal. But if there's already | |
2193 | a saved status that we don't want to flush, we can't resume the | |
2194 | inferior - if it stopped for some other reason we wouldn't have | |
2195 | anywhere to save the new status. In that case, we must leave the | |
2196 | signal unflushed (and possibly generate an extra SIGINT stop). | |
2197 | That's much less bad than losing a signal. */ | |
2198 | while (lp->status == 0 | |
2199 | && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask)) | |
d6b0e80f AC |
2200 | { |
2201 | int ret; | |
2202 | ||
2203 | errno = 0; | |
2204 | ret = ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2205 | if (debug_linux_nat) | |
2206 | fprintf_unfiltered (gdb_stderr, | |
2207 | "FC: Sent PTRACE_CONT, ret %d %d\n", ret, errno); | |
2208 | ||
2209 | lp->stopped = 0; | |
2210 | stop_wait_callback (lp, flush_mask); | |
2211 | if (debug_linux_nat) | |
2212 | fprintf_unfiltered (gdb_stderr, | |
2213 | "FC: Wait finished; saved status is %d\n", | |
2214 | lp->status); | |
2215 | } | |
2216 | ||
2217 | return 0; | |
2218 | } | |
2219 | ||
2220 | /* Return non-zero if LP has a wait status pending. */ | |
2221 | ||
2222 | static int | |
2223 | status_callback (struct lwp_info *lp, void *data) | |
2224 | { | |
2225 | /* Only report a pending wait status if we pretend that this has | |
2226 | indeed been resumed. */ | |
2227 | return (lp->status != 0 && lp->resumed); | |
2228 | } | |
2229 | ||
2230 | /* Return non-zero if LP isn't stopped. */ | |
2231 | ||
2232 | static int | |
2233 | running_callback (struct lwp_info *lp, void *data) | |
2234 | { | |
2235 | return (lp->stopped == 0 || (lp->status != 0 && lp->resumed)); | |
2236 | } | |
2237 | ||
2238 | /* Count the LWP's that have had events. */ | |
2239 | ||
2240 | static int | |
2241 | count_events_callback (struct lwp_info *lp, void *data) | |
2242 | { | |
2243 | int *count = data; | |
2244 | ||
2245 | gdb_assert (count != NULL); | |
2246 | ||
2247 | /* Count only LWPs that have a SIGTRAP event pending. */ | |
2248 | if (lp->status != 0 | |
2249 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) | |
2250 | (*count)++; | |
2251 | ||
2252 | return 0; | |
2253 | } | |
2254 | ||
2255 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2256 | ||
2257 | static int | |
2258 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2259 | { | |
2260 | if (lp->step && lp->status != 0) | |
2261 | return 1; | |
2262 | else | |
2263 | return 0; | |
2264 | } | |
2265 | ||
2266 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2267 | ||
2268 | static int | |
2269 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2270 | { | |
2271 | int *selector = data; | |
2272 | ||
2273 | gdb_assert (selector != NULL); | |
2274 | ||
2275 | /* Select only LWPs that have a SIGTRAP event pending. */ | |
2276 | if (lp->status != 0 | |
2277 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) | |
2278 | if ((*selector)-- == 0) | |
2279 | return 1; | |
2280 | ||
2281 | return 0; | |
2282 | } | |
2283 | ||
710151dd PA |
2284 | static int |
2285 | cancel_breakpoint (struct lwp_info *lp) | |
2286 | { | |
2287 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2288 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2289 | LWP. We will handle the current event, eventually we will resume | |
2290 | this LWP, and this breakpoint will trap again. | |
2291 | ||
2292 | If we do not do this, then we run the risk that the user will | |
2293 | delete or disable the breakpoint, but the LWP will have already | |
2294 | tripped on it. */ | |
2295 | ||
515630c5 UW |
2296 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2297 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2298 | CORE_ADDR pc; | |
2299 | ||
2300 | pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch); | |
2301 | if (breakpoint_inserted_here_p (pc)) | |
710151dd PA |
2302 | { |
2303 | if (debug_linux_nat) | |
2304 | fprintf_unfiltered (gdb_stdlog, | |
2305 | "CB: Push back breakpoint for %s\n", | |
2306 | target_pid_to_str (lp->ptid)); | |
2307 | ||
2308 | /* Back up the PC if necessary. */ | |
515630c5 UW |
2309 | if (gdbarch_decr_pc_after_break (gdbarch)) |
2310 | regcache_write_pc (regcache, pc); | |
2311 | ||
710151dd PA |
2312 | return 1; |
2313 | } | |
2314 | return 0; | |
2315 | } | |
2316 | ||
d6b0e80f AC |
2317 | static int |
2318 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2319 | { | |
2320 | struct lwp_info *event_lp = data; | |
2321 | ||
2322 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2323 | if (lp == event_lp) | |
2324 | return 0; | |
2325 | ||
2326 | /* If a LWP other than the LWP that we're reporting an event for has | |
2327 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2328 | then just arrange for it to hit it 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 | all LWPs, and this one will get its breakpoint 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 | ||
2337 | if (lp->status != 0 | |
2338 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP | |
710151dd PA |
2339 | && cancel_breakpoint (lp)) |
2340 | /* Throw away the SIGTRAP. */ | |
2341 | lp->status = 0; | |
d6b0e80f AC |
2342 | |
2343 | return 0; | |
2344 | } | |
2345 | ||
2346 | /* Select one LWP out of those that have events pending. */ | |
2347 | ||
2348 | static void | |
2349 | select_event_lwp (struct lwp_info **orig_lp, int *status) | |
2350 | { | |
2351 | int num_events = 0; | |
2352 | int random_selector; | |
2353 | struct lwp_info *event_lp; | |
2354 | ||
ac264b3b | 2355 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2356 | (*orig_lp)->status = *status; |
2357 | ||
2358 | /* Give preference to any LWP that is being single-stepped. */ | |
2359 | event_lp = iterate_over_lwps (select_singlestep_lwp_callback, NULL); | |
2360 | if (event_lp != NULL) | |
2361 | { | |
2362 | if (debug_linux_nat) | |
2363 | fprintf_unfiltered (gdb_stdlog, | |
2364 | "SEL: Select single-step %s\n", | |
2365 | target_pid_to_str (event_lp->ptid)); | |
2366 | } | |
2367 | else | |
2368 | { | |
2369 | /* No single-stepping LWP. Select one at random, out of those | |
2370 | which have had SIGTRAP events. */ | |
2371 | ||
2372 | /* First see how many SIGTRAP events we have. */ | |
2373 | iterate_over_lwps (count_events_callback, &num_events); | |
2374 | ||
2375 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2376 | random_selector = (int) | |
2377 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2378 | ||
2379 | if (debug_linux_nat && num_events > 1) | |
2380 | fprintf_unfiltered (gdb_stdlog, | |
2381 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2382 | num_events, random_selector); | |
2383 | ||
2384 | event_lp = iterate_over_lwps (select_event_lwp_callback, | |
2385 | &random_selector); | |
2386 | } | |
2387 | ||
2388 | if (event_lp != NULL) | |
2389 | { | |
2390 | /* Switch the event LWP. */ | |
2391 | *orig_lp = event_lp; | |
2392 | *status = event_lp->status; | |
2393 | } | |
2394 | ||
2395 | /* Flush the wait status for the event LWP. */ | |
2396 | (*orig_lp)->status = 0; | |
2397 | } | |
2398 | ||
2399 | /* Return non-zero if LP has been resumed. */ | |
2400 | ||
2401 | static int | |
2402 | resumed_callback (struct lwp_info *lp, void *data) | |
2403 | { | |
2404 | return lp->resumed; | |
2405 | } | |
2406 | ||
d6b0e80f AC |
2407 | /* Stop an active thread, verify it still exists, then resume it. */ |
2408 | ||
2409 | static int | |
2410 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2411 | { | |
2412 | struct lwp_info *ptr; | |
2413 | ||
2414 | if (!lp->stopped && !lp->signalled) | |
2415 | { | |
2416 | stop_callback (lp, NULL); | |
2417 | stop_wait_callback (lp, NULL); | |
2418 | /* Resume if the lwp still exists. */ | |
2419 | for (ptr = lwp_list; ptr; ptr = ptr->next) | |
2420 | if (lp == ptr) | |
2421 | { | |
2422 | resume_callback (lp, NULL); | |
2423 | resume_set_callback (lp, NULL); | |
2424 | } | |
2425 | } | |
2426 | return 0; | |
2427 | } | |
2428 | ||
02f3fc28 | 2429 | /* Check if we should go on and pass this event to common code. |
fa2c6a57 | 2430 | Return the affected lwp if we are, or NULL otherwise. */ |
02f3fc28 PA |
2431 | static struct lwp_info * |
2432 | linux_nat_filter_event (int lwpid, int status, int options) | |
2433 | { | |
2434 | struct lwp_info *lp; | |
2435 | ||
2436 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
2437 | ||
2438 | /* Check for stop events reported by a process we didn't already | |
2439 | know about - anything not already in our LWP list. | |
2440 | ||
2441 | If we're expecting to receive stopped processes after | |
2442 | fork, vfork, and clone events, then we'll just add the | |
2443 | new one to our list and go back to waiting for the event | |
2444 | to be reported - the stopped process might be returned | |
2445 | from waitpid before or after the event is. */ | |
2446 | if (WIFSTOPPED (status) && !lp) | |
2447 | { | |
2448 | linux_record_stopped_pid (lwpid, status); | |
2449 | return NULL; | |
2450 | } | |
2451 | ||
2452 | /* Make sure we don't report an event for the exit of an LWP not in | |
2453 | our list, i.e. not part of the current process. This can happen | |
2454 | if we detach from a program we original forked and then it | |
2455 | exits. */ | |
2456 | if (!WIFSTOPPED (status) && !lp) | |
2457 | return NULL; | |
2458 | ||
2459 | /* NOTE drow/2003-06-17: This code seems to be meant for debugging | |
2460 | CLONE_PTRACE processes which do not use the thread library - | |
2461 | otherwise we wouldn't find the new LWP this way. That doesn't | |
2462 | currently work, and the following code is currently unreachable | |
2463 | due to the two blocks above. If it's fixed some day, this code | |
2464 | should be broken out into a function so that we can also pick up | |
2465 | LWPs from the new interface. */ | |
2466 | if (!lp) | |
2467 | { | |
2468 | lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid))); | |
2469 | if (options & __WCLONE) | |
2470 | lp->cloned = 1; | |
2471 | ||
2472 | gdb_assert (WIFSTOPPED (status) | |
2473 | && WSTOPSIG (status) == SIGSTOP); | |
2474 | lp->signalled = 1; | |
2475 | ||
2476 | if (!in_thread_list (inferior_ptid)) | |
2477 | { | |
2478 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2479 | GET_PID (inferior_ptid)); | |
2480 | add_thread (inferior_ptid); | |
2481 | } | |
2482 | ||
2483 | add_thread (lp->ptid); | |
2484 | } | |
2485 | ||
2486 | /* Save the trap's siginfo in case we need it later. */ | |
2487 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) | |
2488 | save_siginfo (lp); | |
2489 | ||
2490 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
2491 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2492 | { | |
2493 | if (debug_linux_nat) | |
2494 | fprintf_unfiltered (gdb_stdlog, | |
2495 | "LLW: Handling extended status 0x%06x\n", | |
2496 | status); | |
2497 | if (linux_handle_extended_wait (lp, status, 0)) | |
2498 | return NULL; | |
2499 | } | |
2500 | ||
2501 | /* Check if the thread has exited. */ | |
2502 | if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1) | |
2503 | { | |
2504 | /* If this is the main thread, we must stop all threads and | |
2505 | verify if they are still alive. This is because in the nptl | |
2506 | thread model, there is no signal issued for exiting LWPs | |
2507 | other than the main thread. We only get the main thread exit | |
2508 | signal once all child threads have already exited. If we | |
2509 | stop all the threads and use the stop_wait_callback to check | |
2510 | if they have exited we can determine whether this signal | |
2511 | should be ignored or whether it means the end of the debugged | |
2512 | application, regardless of which threading model is being | |
2513 | used. */ | |
2514 | if (GET_PID (lp->ptid) == GET_LWP (lp->ptid)) | |
2515 | { | |
2516 | lp->stopped = 1; | |
2517 | iterate_over_lwps (stop_and_resume_callback, NULL); | |
2518 | } | |
2519 | ||
2520 | if (debug_linux_nat) | |
2521 | fprintf_unfiltered (gdb_stdlog, | |
2522 | "LLW: %s exited.\n", | |
2523 | target_pid_to_str (lp->ptid)); | |
2524 | ||
2525 | exit_lwp (lp); | |
2526 | ||
2527 | /* If there is at least one more LWP, then the exit signal was | |
2528 | not the end of the debugged application and should be | |
2529 | ignored. */ | |
2530 | if (num_lwps > 0) | |
2531 | { | |
2532 | /* Make sure there is at least one thread running. */ | |
2533 | gdb_assert (iterate_over_lwps (running_callback, NULL)); | |
2534 | ||
2535 | /* Discard the event. */ | |
2536 | return NULL; | |
2537 | } | |
2538 | } | |
2539 | ||
2540 | /* Check if the current LWP has previously exited. In the nptl | |
2541 | thread model, LWPs other than the main thread do not issue | |
2542 | signals when they exit so we must check whenever the thread has | |
2543 | stopped. A similar check is made in stop_wait_callback(). */ | |
2544 | if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid)) | |
2545 | { | |
2546 | if (debug_linux_nat) | |
2547 | fprintf_unfiltered (gdb_stdlog, | |
2548 | "LLW: %s exited.\n", | |
2549 | target_pid_to_str (lp->ptid)); | |
2550 | ||
2551 | exit_lwp (lp); | |
2552 | ||
2553 | /* Make sure there is at least one thread running. */ | |
2554 | gdb_assert (iterate_over_lwps (running_callback, NULL)); | |
2555 | ||
2556 | /* Discard the event. */ | |
2557 | return NULL; | |
2558 | } | |
2559 | ||
2560 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
2561 | an attempt to stop an LWP. */ | |
2562 | if (lp->signalled | |
2563 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
2564 | { | |
2565 | if (debug_linux_nat) | |
2566 | fprintf_unfiltered (gdb_stdlog, | |
2567 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
2568 | target_pid_to_str (lp->ptid)); | |
2569 | ||
2570 | /* This is a delayed SIGSTOP. */ | |
2571 | lp->signalled = 0; | |
2572 | ||
2573 | registers_changed (); | |
2574 | ||
2575 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), | |
2576 | lp->step, TARGET_SIGNAL_0); | |
2577 | if (debug_linux_nat) | |
2578 | fprintf_unfiltered (gdb_stdlog, | |
2579 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
2580 | lp->step ? | |
2581 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2582 | target_pid_to_str (lp->ptid)); | |
2583 | ||
2584 | lp->stopped = 0; | |
2585 | gdb_assert (lp->resumed); | |
2586 | ||
2587 | /* Discard the event. */ | |
2588 | return NULL; | |
2589 | } | |
2590 | ||
2591 | /* An interesting event. */ | |
2592 | gdb_assert (lp); | |
2593 | return lp; | |
2594 | } | |
2595 | ||
b84876c2 PA |
2596 | /* Get the events stored in the pipe into the local queue, so they are |
2597 | accessible to queued_waitpid. We need to do this, since it is not | |
2598 | always the case that the event at the head of the pipe is the event | |
2599 | we want. */ | |
2600 | ||
2601 | static void | |
2602 | pipe_to_local_event_queue (void) | |
2603 | { | |
2604 | if (debug_linux_nat_async) | |
2605 | fprintf_unfiltered (gdb_stdlog, | |
2606 | "PTLEQ: linux_nat_num_queued_events(%d)\n", | |
2607 | linux_nat_num_queued_events); | |
2608 | while (linux_nat_num_queued_events) | |
2609 | { | |
2610 | int lwpid, status, options; | |
b84876c2 | 2611 | lwpid = linux_nat_event_pipe_pop (&status, &options); |
b84876c2 PA |
2612 | gdb_assert (lwpid > 0); |
2613 | push_waitpid (lwpid, status, options); | |
2614 | } | |
2615 | } | |
2616 | ||
2617 | /* Get the unprocessed events stored in the local queue back into the | |
2618 | pipe, so the event loop realizes there's something else to | |
2619 | process. */ | |
2620 | ||
2621 | static void | |
2622 | local_event_queue_to_pipe (void) | |
2623 | { | |
2624 | struct waitpid_result *w = waitpid_queue; | |
2625 | while (w) | |
2626 | { | |
2627 | struct waitpid_result *next = w->next; | |
2628 | linux_nat_event_pipe_push (w->pid, | |
2629 | w->status, | |
2630 | w->options); | |
2631 | xfree (w); | |
2632 | w = next; | |
2633 | } | |
2634 | waitpid_queue = NULL; | |
2635 | ||
2636 | if (debug_linux_nat_async) | |
2637 | fprintf_unfiltered (gdb_stdlog, | |
2638 | "LEQTP: linux_nat_num_queued_events(%d)\n", | |
2639 | linux_nat_num_queued_events); | |
2640 | } | |
2641 | ||
d6b0e80f AC |
2642 | static ptid_t |
2643 | linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
2644 | { | |
2645 | struct lwp_info *lp = NULL; | |
2646 | int options = 0; | |
2647 | int status = 0; | |
2648 | pid_t pid = PIDGET (ptid); | |
2649 | sigset_t flush_mask; | |
2650 | ||
b84876c2 PA |
2651 | if (debug_linux_nat_async) |
2652 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); | |
2653 | ||
f973ed9c DJ |
2654 | /* The first time we get here after starting a new inferior, we may |
2655 | not have added it to the LWP list yet - this is the earliest | |
2656 | moment at which we know its PID. */ | |
2657 | if (num_lwps == 0) | |
2658 | { | |
2659 | gdb_assert (!is_lwp (inferior_ptid)); | |
2660 | ||
2661 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2662 | GET_PID (inferior_ptid)); | |
2663 | lp = add_lwp (inferior_ptid); | |
2664 | lp->resumed = 1; | |
403fe197 PA |
2665 | /* Add the main thread to GDB's thread list. */ |
2666 | add_thread_silent (lp->ptid); | |
f973ed9c DJ |
2667 | } |
2668 | ||
d6b0e80f AC |
2669 | sigemptyset (&flush_mask); |
2670 | ||
84e46146 PA |
2671 | /* Block events while we're here. */ |
2672 | linux_nat_async_events (sigchld_sync); | |
d6b0e80f AC |
2673 | |
2674 | retry: | |
2675 | ||
f973ed9c DJ |
2676 | /* Make sure there is at least one LWP that has been resumed. */ |
2677 | gdb_assert (iterate_over_lwps (resumed_callback, NULL)); | |
d6b0e80f AC |
2678 | |
2679 | /* First check if there is a LWP with a wait status pending. */ | |
2680 | if (pid == -1) | |
2681 | { | |
2682 | /* Any LWP that's been resumed will do. */ | |
2683 | lp = iterate_over_lwps (status_callback, NULL); | |
2684 | if (lp) | |
2685 | { | |
710151dd PA |
2686 | if (target_can_async_p ()) |
2687 | internal_error (__FILE__, __LINE__, | |
2688 | "Found an LWP with a pending status in async mode."); | |
2689 | ||
d6b0e80f AC |
2690 | status = lp->status; |
2691 | lp->status = 0; | |
2692 | ||
2693 | if (debug_linux_nat && status) | |
2694 | fprintf_unfiltered (gdb_stdlog, | |
2695 | "LLW: Using pending wait status %s for %s.\n", | |
2696 | status_to_str (status), | |
2697 | target_pid_to_str (lp->ptid)); | |
2698 | } | |
2699 | ||
b84876c2 | 2700 | /* But if we don't find one, we'll have to wait, and check both |
d6b0e80f AC |
2701 | cloned and uncloned processes. We start with the cloned |
2702 | processes. */ | |
2703 | options = __WCLONE | WNOHANG; | |
2704 | } | |
2705 | else if (is_lwp (ptid)) | |
2706 | { | |
2707 | if (debug_linux_nat) | |
2708 | fprintf_unfiltered (gdb_stdlog, | |
2709 | "LLW: Waiting for specific LWP %s.\n", | |
2710 | target_pid_to_str (ptid)); | |
2711 | ||
2712 | /* We have a specific LWP to check. */ | |
2713 | lp = find_lwp_pid (ptid); | |
2714 | gdb_assert (lp); | |
2715 | status = lp->status; | |
2716 | lp->status = 0; | |
2717 | ||
2718 | if (debug_linux_nat && status) | |
2719 | fprintf_unfiltered (gdb_stdlog, | |
2720 | "LLW: Using pending wait status %s for %s.\n", | |
2721 | status_to_str (status), | |
2722 | target_pid_to_str (lp->ptid)); | |
2723 | ||
2724 | /* If we have to wait, take into account whether PID is a cloned | |
2725 | process or not. And we have to convert it to something that | |
2726 | the layer beneath us can understand. */ | |
2727 | options = lp->cloned ? __WCLONE : 0; | |
2728 | pid = GET_LWP (ptid); | |
2729 | } | |
2730 | ||
2731 | if (status && lp->signalled) | |
2732 | { | |
2733 | /* A pending SIGSTOP may interfere with the normal stream of | |
2734 | events. In a typical case where interference is a problem, | |
2735 | we have a SIGSTOP signal pending for LWP A while | |
2736 | single-stepping it, encounter an event in LWP B, and take the | |
2737 | pending SIGSTOP while trying to stop LWP A. After processing | |
2738 | the event in LWP B, LWP A is continued, and we'll never see | |
2739 | the SIGTRAP associated with the last time we were | |
2740 | single-stepping LWP A. */ | |
2741 | ||
2742 | /* Resume the thread. It should halt immediately returning the | |
2743 | pending SIGSTOP. */ | |
2744 | registers_changed (); | |
10d6c8cd DJ |
2745 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2746 | lp->step, TARGET_SIGNAL_0); | |
d6b0e80f AC |
2747 | if (debug_linux_nat) |
2748 | fprintf_unfiltered (gdb_stdlog, | |
2749 | "LLW: %s %s, 0, 0 (expect SIGSTOP)\n", | |
2750 | lp->step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2751 | target_pid_to_str (lp->ptid)); | |
2752 | lp->stopped = 0; | |
2753 | gdb_assert (lp->resumed); | |
2754 | ||
2755 | /* This should catch the pending SIGSTOP. */ | |
2756 | stop_wait_callback (lp, NULL); | |
2757 | } | |
2758 | ||
b84876c2 PA |
2759 | if (!target_can_async_p ()) |
2760 | { | |
2761 | /* Causes SIGINT to be passed on to the attached process. */ | |
2762 | set_sigint_trap (); | |
2763 | set_sigio_trap (); | |
2764 | } | |
d6b0e80f AC |
2765 | |
2766 | while (status == 0) | |
2767 | { | |
2768 | pid_t lwpid; | |
2769 | ||
b84876c2 PA |
2770 | if (target_can_async_p ()) |
2771 | /* In async mode, don't ever block. Only look at the locally | |
2772 | queued events. */ | |
2773 | lwpid = queued_waitpid (pid, &status, options); | |
2774 | else | |
2775 | lwpid = my_waitpid (pid, &status, options); | |
2776 | ||
d6b0e80f AC |
2777 | if (lwpid > 0) |
2778 | { | |
2779 | gdb_assert (pid == -1 || lwpid == pid); | |
2780 | ||
2781 | if (debug_linux_nat) | |
2782 | { | |
2783 | fprintf_unfiltered (gdb_stdlog, | |
2784 | "LLW: waitpid %ld received %s\n", | |
2785 | (long) lwpid, status_to_str (status)); | |
2786 | } | |
2787 | ||
02f3fc28 | 2788 | lp = linux_nat_filter_event (lwpid, status, options); |
d6b0e80f AC |
2789 | if (!lp) |
2790 | { | |
02f3fc28 | 2791 | /* A discarded event. */ |
d6b0e80f AC |
2792 | status = 0; |
2793 | continue; | |
2794 | } | |
2795 | ||
2796 | break; | |
2797 | } | |
2798 | ||
2799 | if (pid == -1) | |
2800 | { | |
2801 | /* Alternate between checking cloned and uncloned processes. */ | |
2802 | options ^= __WCLONE; | |
2803 | ||
b84876c2 PA |
2804 | /* And every time we have checked both: |
2805 | In async mode, return to event loop; | |
2806 | In sync mode, suspend waiting for a SIGCHLD signal. */ | |
d6b0e80f | 2807 | if (options & __WCLONE) |
b84876c2 PA |
2808 | { |
2809 | if (target_can_async_p ()) | |
2810 | { | |
2811 | /* No interesting event. */ | |
2812 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
2813 | ||
2814 | /* Get ready for the next event. */ | |
2815 | target_async (inferior_event_handler, 0); | |
2816 | ||
2817 | if (debug_linux_nat_async) | |
2818 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); | |
2819 | ||
2820 | return minus_one_ptid; | |
2821 | } | |
2822 | ||
2823 | sigsuspend (&suspend_mask); | |
2824 | } | |
d6b0e80f AC |
2825 | } |
2826 | ||
2827 | /* We shouldn't end up here unless we want to try again. */ | |
2828 | gdb_assert (status == 0); | |
2829 | } | |
2830 | ||
b84876c2 PA |
2831 | if (!target_can_async_p ()) |
2832 | { | |
2833 | clear_sigio_trap (); | |
2834 | clear_sigint_trap (); | |
2835 | } | |
d6b0e80f AC |
2836 | |
2837 | gdb_assert (lp); | |
2838 | ||
2839 | /* Don't report signals that GDB isn't interested in, such as | |
2840 | signals that are neither printed nor stopped upon. Stopping all | |
2841 | threads can be a bit time-consuming so if we want decent | |
2842 | performance with heavily multi-threaded programs, especially when | |
2843 | they're using a high frequency timer, we'd better avoid it if we | |
2844 | can. */ | |
2845 | ||
2846 | if (WIFSTOPPED (status)) | |
2847 | { | |
2848 | int signo = target_signal_from_host (WSTOPSIG (status)); | |
2849 | ||
d539ed7e UW |
2850 | /* If we get a signal while single-stepping, we may need special |
2851 | care, e.g. to skip the signal handler. Defer to common code. */ | |
2852 | if (!lp->step | |
2853 | && signal_stop_state (signo) == 0 | |
d6b0e80f AC |
2854 | && signal_print_state (signo) == 0 |
2855 | && signal_pass_state (signo) == 1) | |
2856 | { | |
2857 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
2858 | here? It is not clear we should. GDB may not expect | |
2859 | other threads to run. On the other hand, not resuming | |
2860 | newly attached threads may cause an unwanted delay in | |
2861 | getting them running. */ | |
2862 | registers_changed (); | |
10d6c8cd DJ |
2863 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2864 | lp->step, signo); | |
d6b0e80f AC |
2865 | if (debug_linux_nat) |
2866 | fprintf_unfiltered (gdb_stdlog, | |
2867 | "LLW: %s %s, %s (preempt 'handle')\n", | |
2868 | lp->step ? | |
2869 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2870 | target_pid_to_str (lp->ptid), | |
2871 | signo ? strsignal (signo) : "0"); | |
2872 | lp->stopped = 0; | |
2873 | status = 0; | |
2874 | goto retry; | |
2875 | } | |
2876 | ||
2877 | if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0) | |
2878 | { | |
2879 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
2880 | forwarded to the entire process group, that is, all LWP's | |
2881 | will receive it. Since we only want to report it once, | |
2882 | we try to flush it from all LWPs except this one. */ | |
2883 | sigaddset (&flush_mask, SIGINT); | |
2884 | } | |
2885 | } | |
2886 | ||
2887 | /* This LWP is stopped now. */ | |
2888 | lp->stopped = 1; | |
2889 | ||
2890 | if (debug_linux_nat) | |
2891 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
2892 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
2893 | ||
2894 | /* Now stop all other LWP's ... */ | |
2895 | iterate_over_lwps (stop_callback, NULL); | |
2896 | ||
2897 | /* ... and wait until all of them have reported back that they're no | |
2898 | longer running. */ | |
2899 | iterate_over_lwps (stop_wait_callback, &flush_mask); | |
2900 | iterate_over_lwps (flush_callback, &flush_mask); | |
2901 | ||
2902 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
2903 | among those that have had events. Giving equal priority to all | |
2904 | LWPs that have had events helps prevent starvation. */ | |
2905 | if (pid == -1) | |
2906 | select_event_lwp (&lp, &status); | |
2907 | ||
2908 | /* Now that we've selected our final event LWP, cancel any | |
2909 | breakpoints in other LWPs that have hit a GDB breakpoint. See | |
2910 | the comment in cancel_breakpoints_callback to find out why. */ | |
2911 | iterate_over_lwps (cancel_breakpoints_callback, lp); | |
2912 | ||
d6b0e80f AC |
2913 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) |
2914 | { | |
d6b0e80f AC |
2915 | if (debug_linux_nat) |
2916 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
2917 | "LLW: trap ptid is %s.\n", |
2918 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 2919 | } |
d6b0e80f AC |
2920 | |
2921 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2922 | { | |
2923 | *ourstatus = lp->waitstatus; | |
2924 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
2925 | } | |
2926 | else | |
2927 | store_waitstatus (ourstatus, status); | |
2928 | ||
b84876c2 PA |
2929 | /* Get ready for the next event. */ |
2930 | if (target_can_async_p ()) | |
2931 | target_async (inferior_event_handler, 0); | |
2932 | ||
2933 | if (debug_linux_nat_async) | |
2934 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); | |
2935 | ||
f973ed9c | 2936 | return lp->ptid; |
d6b0e80f AC |
2937 | } |
2938 | ||
2939 | static int | |
2940 | kill_callback (struct lwp_info *lp, void *data) | |
2941 | { | |
2942 | errno = 0; | |
2943 | ptrace (PTRACE_KILL, GET_LWP (lp->ptid), 0, 0); | |
2944 | if (debug_linux_nat) | |
2945 | fprintf_unfiltered (gdb_stdlog, | |
2946 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
2947 | target_pid_to_str (lp->ptid), | |
2948 | errno ? safe_strerror (errno) : "OK"); | |
2949 | ||
2950 | return 0; | |
2951 | } | |
2952 | ||
2953 | static int | |
2954 | kill_wait_callback (struct lwp_info *lp, void *data) | |
2955 | { | |
2956 | pid_t pid; | |
2957 | ||
2958 | /* We must make sure that there are no pending events (delayed | |
2959 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
2960 | program doesn't interfere with any following debugging session. */ | |
2961 | ||
2962 | /* For cloned processes we must check both with __WCLONE and | |
2963 | without, since the exit status of a cloned process isn't reported | |
2964 | with __WCLONE. */ | |
2965 | if (lp->cloned) | |
2966 | { | |
2967 | do | |
2968 | { | |
58aecb61 | 2969 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE); |
e85a822c | 2970 | if (pid != (pid_t) -1) |
d6b0e80f | 2971 | { |
e85a822c DJ |
2972 | if (debug_linux_nat) |
2973 | fprintf_unfiltered (gdb_stdlog, | |
2974 | "KWC: wait %s received unknown.\n", | |
2975 | target_pid_to_str (lp->ptid)); | |
2976 | /* The Linux kernel sometimes fails to kill a thread | |
2977 | completely after PTRACE_KILL; that goes from the stop | |
2978 | point in do_fork out to the one in | |
2979 | get_signal_to_deliever and waits again. So kill it | |
2980 | again. */ | |
2981 | kill_callback (lp, NULL); | |
d6b0e80f AC |
2982 | } |
2983 | } | |
2984 | while (pid == GET_LWP (lp->ptid)); | |
2985 | ||
2986 | gdb_assert (pid == -1 && errno == ECHILD); | |
2987 | } | |
2988 | ||
2989 | do | |
2990 | { | |
58aecb61 | 2991 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0); |
e85a822c | 2992 | if (pid != (pid_t) -1) |
d6b0e80f | 2993 | { |
e85a822c DJ |
2994 | if (debug_linux_nat) |
2995 | fprintf_unfiltered (gdb_stdlog, | |
2996 | "KWC: wait %s received unk.\n", | |
2997 | target_pid_to_str (lp->ptid)); | |
2998 | /* See the call to kill_callback above. */ | |
2999 | kill_callback (lp, NULL); | |
d6b0e80f AC |
3000 | } |
3001 | } | |
3002 | while (pid == GET_LWP (lp->ptid)); | |
3003 | ||
3004 | gdb_assert (pid == -1 && errno == ECHILD); | |
3005 | return 0; | |
3006 | } | |
3007 | ||
3008 | static void | |
3009 | linux_nat_kill (void) | |
3010 | { | |
f973ed9c DJ |
3011 | struct target_waitstatus last; |
3012 | ptid_t last_ptid; | |
3013 | int status; | |
d6b0e80f | 3014 | |
b84876c2 PA |
3015 | if (target_can_async_p ()) |
3016 | target_async (NULL, 0); | |
3017 | ||
f973ed9c DJ |
3018 | /* If we're stopped while forking and we haven't followed yet, |
3019 | kill the other task. We need to do this first because the | |
3020 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 3021 | |
f973ed9c | 3022 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 3023 | |
f973ed9c DJ |
3024 | if (last.kind == TARGET_WAITKIND_FORKED |
3025 | || last.kind == TARGET_WAITKIND_VFORKED) | |
3026 | { | |
3a3e9ee3 | 3027 | ptrace (PT_KILL, PIDGET (last.value.related_pid), 0, 0); |
f973ed9c DJ |
3028 | wait (&status); |
3029 | } | |
3030 | ||
3031 | if (forks_exist_p ()) | |
b84876c2 PA |
3032 | { |
3033 | linux_fork_killall (); | |
3034 | drain_queued_events (-1); | |
3035 | } | |
f973ed9c DJ |
3036 | else |
3037 | { | |
3038 | /* Kill all LWP's ... */ | |
3039 | iterate_over_lwps (kill_callback, NULL); | |
3040 | ||
3041 | /* ... and wait until we've flushed all events. */ | |
3042 | iterate_over_lwps (kill_wait_callback, NULL); | |
3043 | } | |
3044 | ||
3045 | target_mourn_inferior (); | |
d6b0e80f AC |
3046 | } |
3047 | ||
3048 | static void | |
3049 | linux_nat_mourn_inferior (void) | |
3050 | { | |
d6b0e80f AC |
3051 | /* Destroy LWP info; it's no longer valid. */ |
3052 | init_lwp_list (); | |
3053 | ||
f973ed9c | 3054 | if (! forks_exist_p ()) |
b84876c2 PA |
3055 | { |
3056 | /* Normal case, no other forks available. */ | |
3057 | if (target_can_async_p ()) | |
3058 | linux_nat_async (NULL, 0); | |
3059 | linux_ops->to_mourn_inferior (); | |
3060 | } | |
f973ed9c DJ |
3061 | else |
3062 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3063 | there are other viable forks to debug. Delete the exiting | |
3064 | one and context-switch to the first available. */ | |
3065 | linux_fork_mourn_inferior (); | |
d6b0e80f AC |
3066 | } |
3067 | ||
10d6c8cd DJ |
3068 | static LONGEST |
3069 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, | |
3070 | const char *annex, gdb_byte *readbuf, | |
3071 | const gdb_byte *writebuf, | |
3072 | ULONGEST offset, LONGEST len) | |
d6b0e80f AC |
3073 | { |
3074 | struct cleanup *old_chain = save_inferior_ptid (); | |
10d6c8cd | 3075 | LONGEST xfer; |
d6b0e80f AC |
3076 | |
3077 | if (is_lwp (inferior_ptid)) | |
3078 | inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid)); | |
3079 | ||
10d6c8cd DJ |
3080 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
3081 | offset, len); | |
d6b0e80f AC |
3082 | |
3083 | do_cleanups (old_chain); | |
3084 | return xfer; | |
3085 | } | |
3086 | ||
3087 | static int | |
3088 | linux_nat_thread_alive (ptid_t ptid) | |
3089 | { | |
3090 | gdb_assert (is_lwp (ptid)); | |
3091 | ||
3092 | errno = 0; | |
3093 | ptrace (PTRACE_PEEKUSER, GET_LWP (ptid), 0, 0); | |
3094 | if (debug_linux_nat) | |
3095 | fprintf_unfiltered (gdb_stdlog, | |
3096 | "LLTA: PTRACE_PEEKUSER %s, 0, 0 (%s)\n", | |
3097 | target_pid_to_str (ptid), | |
3098 | errno ? safe_strerror (errno) : "OK"); | |
9c0dd46b | 3099 | |
155bd5d1 AC |
3100 | /* Not every Linux kernel implements PTRACE_PEEKUSER. But we can |
3101 | handle that case gracefully since ptrace will first do a lookup | |
3102 | for the process based upon the passed-in pid. If that fails we | |
3103 | will get either -ESRCH or -EPERM, otherwise the child exists and | |
3104 | is alive. */ | |
a529be7c | 3105 | if (errno == ESRCH || errno == EPERM) |
d6b0e80f AC |
3106 | return 0; |
3107 | ||
3108 | return 1; | |
3109 | } | |
3110 | ||
3111 | static char * | |
3112 | linux_nat_pid_to_str (ptid_t ptid) | |
3113 | { | |
3114 | static char buf[64]; | |
3115 | ||
a0ef4274 DJ |
3116 | if (is_lwp (ptid) |
3117 | && ((lwp_list && lwp_list->next) | |
3118 | || GET_PID (ptid) != GET_LWP (ptid))) | |
d6b0e80f AC |
3119 | { |
3120 | snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid)); | |
3121 | return buf; | |
3122 | } | |
3123 | ||
3124 | return normal_pid_to_str (ptid); | |
3125 | } | |
3126 | ||
d6b0e80f AC |
3127 | static void |
3128 | sigchld_handler (int signo) | |
3129 | { | |
b84876c2 | 3130 | if (linux_nat_async_enabled |
84e46146 | 3131 | && linux_nat_async_events_state != sigchld_sync |
b84876c2 PA |
3132 | && signo == SIGCHLD) |
3133 | /* It is *always* a bug to hit this. */ | |
3134 | internal_error (__FILE__, __LINE__, | |
3135 | "sigchld_handler called when async events are enabled"); | |
3136 | ||
d6b0e80f AC |
3137 | /* Do nothing. The only reason for this handler is that it allows |
3138 | us to use sigsuspend in linux_nat_wait above to wait for the | |
3139 | arrival of a SIGCHLD. */ | |
3140 | } | |
3141 | ||
dba24537 AC |
3142 | /* Accepts an integer PID; Returns a string representing a file that |
3143 | can be opened to get the symbols for the child process. */ | |
3144 | ||
6d8fd2b7 UW |
3145 | static char * |
3146 | linux_child_pid_to_exec_file (int pid) | |
dba24537 AC |
3147 | { |
3148 | char *name1, *name2; | |
3149 | ||
3150 | name1 = xmalloc (MAXPATHLEN); | |
3151 | name2 = xmalloc (MAXPATHLEN); | |
3152 | make_cleanup (xfree, name1); | |
3153 | make_cleanup (xfree, name2); | |
3154 | memset (name2, 0, MAXPATHLEN); | |
3155 | ||
3156 | sprintf (name1, "/proc/%d/exe", pid); | |
3157 | if (readlink (name1, name2, MAXPATHLEN) > 0) | |
3158 | return name2; | |
3159 | else | |
3160 | return name1; | |
3161 | } | |
3162 | ||
3163 | /* Service function for corefiles and info proc. */ | |
3164 | ||
3165 | static int | |
3166 | read_mapping (FILE *mapfile, | |
3167 | long long *addr, | |
3168 | long long *endaddr, | |
3169 | char *permissions, | |
3170 | long long *offset, | |
3171 | char *device, long long *inode, char *filename) | |
3172 | { | |
3173 | int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx", | |
3174 | addr, endaddr, permissions, offset, device, inode); | |
3175 | ||
2e14c2ea MS |
3176 | filename[0] = '\0'; |
3177 | if (ret > 0 && ret != EOF) | |
dba24537 AC |
3178 | { |
3179 | /* Eat everything up to EOL for the filename. This will prevent | |
3180 | weird filenames (such as one with embedded whitespace) from | |
3181 | confusing this code. It also makes this code more robust in | |
3182 | respect to annotations the kernel may add after the filename. | |
3183 | ||
3184 | Note the filename is used for informational purposes | |
3185 | only. */ | |
3186 | ret += fscanf (mapfile, "%[^\n]\n", filename); | |
3187 | } | |
2e14c2ea | 3188 | |
dba24537 AC |
3189 | return (ret != 0 && ret != EOF); |
3190 | } | |
3191 | ||
3192 | /* Fills the "to_find_memory_regions" target vector. Lists the memory | |
3193 | regions in the inferior for a corefile. */ | |
3194 | ||
3195 | static int | |
3196 | linux_nat_find_memory_regions (int (*func) (CORE_ADDR, | |
3197 | unsigned long, | |
3198 | int, int, int, void *), void *obfd) | |
3199 | { | |
3200 | long long pid = PIDGET (inferior_ptid); | |
3201 | char mapsfilename[MAXPATHLEN]; | |
3202 | FILE *mapsfile; | |
3203 | long long addr, endaddr, size, offset, inode; | |
3204 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3205 | int read, write, exec; | |
3206 | int ret; | |
3207 | ||
3208 | /* Compose the filename for the /proc memory map, and open it. */ | |
3209 | sprintf (mapsfilename, "/proc/%lld/maps", pid); | |
3210 | if ((mapsfile = fopen (mapsfilename, "r")) == NULL) | |
8a3fe4f8 | 3211 | error (_("Could not open %s."), mapsfilename); |
dba24537 AC |
3212 | |
3213 | if (info_verbose) | |
3214 | fprintf_filtered (gdb_stdout, | |
3215 | "Reading memory regions from %s\n", mapsfilename); | |
3216 | ||
3217 | /* Now iterate until end-of-file. */ | |
3218 | while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0], | |
3219 | &offset, &device[0], &inode, &filename[0])) | |
3220 | { | |
3221 | size = endaddr - addr; | |
3222 | ||
3223 | /* Get the segment's permissions. */ | |
3224 | read = (strchr (permissions, 'r') != 0); | |
3225 | write = (strchr (permissions, 'w') != 0); | |
3226 | exec = (strchr (permissions, 'x') != 0); | |
3227 | ||
3228 | if (info_verbose) | |
3229 | { | |
3230 | fprintf_filtered (gdb_stdout, | |
3231 | "Save segment, %lld bytes at 0x%s (%c%c%c)", | |
3232 | size, paddr_nz (addr), | |
3233 | read ? 'r' : ' ', | |
3234 | write ? 'w' : ' ', exec ? 'x' : ' '); | |
b260b6c1 | 3235 | if (filename[0]) |
dba24537 AC |
3236 | fprintf_filtered (gdb_stdout, " for %s", filename); |
3237 | fprintf_filtered (gdb_stdout, "\n"); | |
3238 | } | |
3239 | ||
3240 | /* Invoke the callback function to create the corefile | |
3241 | segment. */ | |
3242 | func (addr, size, read, write, exec, obfd); | |
3243 | } | |
3244 | fclose (mapsfile); | |
3245 | return 0; | |
3246 | } | |
3247 | ||
3248 | /* Records the thread's register state for the corefile note | |
3249 | section. */ | |
3250 | ||
3251 | static char * | |
3252 | linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid, | |
3253 | char *note_data, int *note_size) | |
3254 | { | |
3255 | gdb_gregset_t gregs; | |
3256 | gdb_fpregset_t fpregs; | |
dba24537 | 3257 | unsigned long lwp = ptid_get_lwp (ptid); |
594f7785 UW |
3258 | struct regcache *regcache = get_thread_regcache (ptid); |
3259 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
4f844a66 | 3260 | const struct regset *regset; |
55e969c1 | 3261 | int core_regset_p; |
594f7785 | 3262 | struct cleanup *old_chain; |
17ea7499 CES |
3263 | struct core_regset_section *sect_list; |
3264 | char *gdb_regset; | |
594f7785 UW |
3265 | |
3266 | old_chain = save_inferior_ptid (); | |
3267 | inferior_ptid = ptid; | |
3268 | target_fetch_registers (regcache, -1); | |
3269 | do_cleanups (old_chain); | |
4f844a66 DM |
3270 | |
3271 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
17ea7499 CES |
3272 | sect_list = gdbarch_core_regset_sections (gdbarch); |
3273 | ||
55e969c1 DM |
3274 | if (core_regset_p |
3275 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
3276 | sizeof (gregs))) != NULL | |
3277 | && regset->collect_regset != NULL) | |
594f7785 | 3278 | regset->collect_regset (regset, regcache, -1, |
55e969c1 | 3279 | &gregs, sizeof (gregs)); |
4f844a66 | 3280 | else |
594f7785 | 3281 | fill_gregset (regcache, &gregs, -1); |
4f844a66 | 3282 | |
55e969c1 DM |
3283 | note_data = (char *) elfcore_write_prstatus (obfd, |
3284 | note_data, | |
3285 | note_size, | |
3286 | lwp, | |
3287 | stop_signal, &gregs); | |
3288 | ||
17ea7499 CES |
3289 | /* The loop below uses the new struct core_regset_section, which stores |
3290 | the supported section names and sizes for the core file. Note that | |
3291 | note PRSTATUS needs to be treated specially. But the other notes are | |
3292 | structurally the same, so they can benefit from the new struct. */ | |
3293 | if (core_regset_p && sect_list != NULL) | |
3294 | while (sect_list->sect_name != NULL) | |
3295 | { | |
3296 | /* .reg was already handled above. */ | |
3297 | if (strcmp (sect_list->sect_name, ".reg") == 0) | |
3298 | { | |
3299 | sect_list++; | |
3300 | continue; | |
3301 | } | |
3302 | regset = gdbarch_regset_from_core_section (gdbarch, | |
3303 | sect_list->sect_name, | |
3304 | sect_list->size); | |
3305 | gdb_assert (regset && regset->collect_regset); | |
3306 | gdb_regset = xmalloc (sect_list->size); | |
3307 | regset->collect_regset (regset, regcache, -1, | |
3308 | gdb_regset, sect_list->size); | |
3309 | note_data = (char *) elfcore_write_register_note (obfd, | |
3310 | note_data, | |
3311 | note_size, | |
3312 | sect_list->sect_name, | |
3313 | gdb_regset, | |
3314 | sect_list->size); | |
3315 | xfree (gdb_regset); | |
3316 | sect_list++; | |
3317 | } | |
dba24537 | 3318 | |
17ea7499 CES |
3319 | /* For architectures that does not have the struct core_regset_section |
3320 | implemented, we use the old method. When all the architectures have | |
3321 | the new support, the code below should be deleted. */ | |
4f844a66 | 3322 | else |
17ea7499 CES |
3323 | { |
3324 | if (core_regset_p | |
3325 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
3326 | sizeof (fpregs))) != NULL | |
3327 | && regset->collect_regset != NULL) | |
3328 | regset->collect_regset (regset, regcache, -1, | |
3329 | &fpregs, sizeof (fpregs)); | |
3330 | else | |
3331 | fill_fpregset (regcache, &fpregs, -1); | |
3332 | ||
3333 | note_data = (char *) elfcore_write_prfpreg (obfd, | |
3334 | note_data, | |
3335 | note_size, | |
3336 | &fpregs, sizeof (fpregs)); | |
3337 | } | |
4f844a66 | 3338 | |
dba24537 AC |
3339 | return note_data; |
3340 | } | |
3341 | ||
3342 | struct linux_nat_corefile_thread_data | |
3343 | { | |
3344 | bfd *obfd; | |
3345 | char *note_data; | |
3346 | int *note_size; | |
3347 | int num_notes; | |
3348 | }; | |
3349 | ||
3350 | /* Called by gdbthread.c once per thread. Records the thread's | |
3351 | register state for the corefile note section. */ | |
3352 | ||
3353 | static int | |
3354 | linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data) | |
3355 | { | |
3356 | struct linux_nat_corefile_thread_data *args = data; | |
dba24537 | 3357 | |
dba24537 AC |
3358 | args->note_data = linux_nat_do_thread_registers (args->obfd, |
3359 | ti->ptid, | |
3360 | args->note_data, | |
3361 | args->note_size); | |
3362 | args->num_notes++; | |
56be3814 | 3363 | |
dba24537 AC |
3364 | return 0; |
3365 | } | |
3366 | ||
3367 | /* Records the register state for the corefile note section. */ | |
3368 | ||
3369 | static char * | |
3370 | linux_nat_do_registers (bfd *obfd, ptid_t ptid, | |
3371 | char *note_data, int *note_size) | |
3372 | { | |
dba24537 AC |
3373 | return linux_nat_do_thread_registers (obfd, |
3374 | ptid_build (ptid_get_pid (inferior_ptid), | |
3375 | ptid_get_pid (inferior_ptid), | |
3376 | 0), | |
3377 | note_data, note_size); | |
dba24537 AC |
3378 | } |
3379 | ||
3380 | /* Fills the "to_make_corefile_note" target vector. Builds the note | |
3381 | section for a corefile, and returns it in a malloc buffer. */ | |
3382 | ||
3383 | static char * | |
3384 | linux_nat_make_corefile_notes (bfd *obfd, int *note_size) | |
3385 | { | |
3386 | struct linux_nat_corefile_thread_data thread_args; | |
3387 | struct cleanup *old_chain; | |
d99148ef | 3388 | /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */ |
dba24537 | 3389 | char fname[16] = { '\0' }; |
d99148ef | 3390 | /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */ |
dba24537 AC |
3391 | char psargs[80] = { '\0' }; |
3392 | char *note_data = NULL; | |
3393 | ptid_t current_ptid = inferior_ptid; | |
c6826062 | 3394 | gdb_byte *auxv; |
dba24537 AC |
3395 | int auxv_len; |
3396 | ||
3397 | if (get_exec_file (0)) | |
3398 | { | |
3399 | strncpy (fname, strrchr (get_exec_file (0), '/') + 1, sizeof (fname)); | |
3400 | strncpy (psargs, get_exec_file (0), sizeof (psargs)); | |
3401 | if (get_inferior_args ()) | |
3402 | { | |
d99148ef JK |
3403 | char *string_end; |
3404 | char *psargs_end = psargs + sizeof (psargs); | |
3405 | ||
3406 | /* linux_elfcore_write_prpsinfo () handles zero unterminated | |
3407 | strings fine. */ | |
3408 | string_end = memchr (psargs, 0, sizeof (psargs)); | |
3409 | if (string_end != NULL) | |
3410 | { | |
3411 | *string_end++ = ' '; | |
3412 | strncpy (string_end, get_inferior_args (), | |
3413 | psargs_end - string_end); | |
3414 | } | |
dba24537 AC |
3415 | } |
3416 | note_data = (char *) elfcore_write_prpsinfo (obfd, | |
3417 | note_data, | |
3418 | note_size, fname, psargs); | |
3419 | } | |
3420 | ||
3421 | /* Dump information for threads. */ | |
3422 | thread_args.obfd = obfd; | |
3423 | thread_args.note_data = note_data; | |
3424 | thread_args.note_size = note_size; | |
3425 | thread_args.num_notes = 0; | |
3426 | iterate_over_lwps (linux_nat_corefile_thread_callback, &thread_args); | |
3427 | if (thread_args.num_notes == 0) | |
3428 | { | |
3429 | /* iterate_over_threads didn't come up with any threads; just | |
3430 | use inferior_ptid. */ | |
3431 | note_data = linux_nat_do_registers (obfd, inferior_ptid, | |
3432 | note_data, note_size); | |
3433 | } | |
3434 | else | |
3435 | { | |
3436 | note_data = thread_args.note_data; | |
3437 | } | |
3438 | ||
13547ab6 DJ |
3439 | auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV, |
3440 | NULL, &auxv); | |
dba24537 AC |
3441 | if (auxv_len > 0) |
3442 | { | |
3443 | note_data = elfcore_write_note (obfd, note_data, note_size, | |
3444 | "CORE", NT_AUXV, auxv, auxv_len); | |
3445 | xfree (auxv); | |
3446 | } | |
3447 | ||
3448 | make_cleanup (xfree, note_data); | |
3449 | return note_data; | |
3450 | } | |
3451 | ||
3452 | /* Implement the "info proc" command. */ | |
3453 | ||
3454 | static void | |
3455 | linux_nat_info_proc_cmd (char *args, int from_tty) | |
3456 | { | |
3457 | long long pid = PIDGET (inferior_ptid); | |
3458 | FILE *procfile; | |
3459 | char **argv = NULL; | |
3460 | char buffer[MAXPATHLEN]; | |
3461 | char fname1[MAXPATHLEN], fname2[MAXPATHLEN]; | |
3462 | int cmdline_f = 1; | |
3463 | int cwd_f = 1; | |
3464 | int exe_f = 1; | |
3465 | int mappings_f = 0; | |
3466 | int environ_f = 0; | |
3467 | int status_f = 0; | |
3468 | int stat_f = 0; | |
3469 | int all = 0; | |
3470 | struct stat dummy; | |
3471 | ||
3472 | if (args) | |
3473 | { | |
3474 | /* Break up 'args' into an argv array. */ | |
3475 | if ((argv = buildargv (args)) == NULL) | |
3476 | nomem (0); | |
3477 | else | |
3478 | make_cleanup_freeargv (argv); | |
3479 | } | |
3480 | while (argv != NULL && *argv != NULL) | |
3481 | { | |
3482 | if (isdigit (argv[0][0])) | |
3483 | { | |
3484 | pid = strtoul (argv[0], NULL, 10); | |
3485 | } | |
3486 | else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0) | |
3487 | { | |
3488 | mappings_f = 1; | |
3489 | } | |
3490 | else if (strcmp (argv[0], "status") == 0) | |
3491 | { | |
3492 | status_f = 1; | |
3493 | } | |
3494 | else if (strcmp (argv[0], "stat") == 0) | |
3495 | { | |
3496 | stat_f = 1; | |
3497 | } | |
3498 | else if (strcmp (argv[0], "cmd") == 0) | |
3499 | { | |
3500 | cmdline_f = 1; | |
3501 | } | |
3502 | else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0) | |
3503 | { | |
3504 | exe_f = 1; | |
3505 | } | |
3506 | else if (strcmp (argv[0], "cwd") == 0) | |
3507 | { | |
3508 | cwd_f = 1; | |
3509 | } | |
3510 | else if (strncmp (argv[0], "all", strlen (argv[0])) == 0) | |
3511 | { | |
3512 | all = 1; | |
3513 | } | |
3514 | else | |
3515 | { | |
3516 | /* [...] (future options here) */ | |
3517 | } | |
3518 | argv++; | |
3519 | } | |
3520 | if (pid == 0) | |
8a3fe4f8 | 3521 | error (_("No current process: you must name one.")); |
dba24537 AC |
3522 | |
3523 | sprintf (fname1, "/proc/%lld", pid); | |
3524 | if (stat (fname1, &dummy) != 0) | |
8a3fe4f8 | 3525 | error (_("No /proc directory: '%s'"), fname1); |
dba24537 | 3526 | |
a3f17187 | 3527 | printf_filtered (_("process %lld\n"), pid); |
dba24537 AC |
3528 | if (cmdline_f || all) |
3529 | { | |
3530 | sprintf (fname1, "/proc/%lld/cmdline", pid); | |
d5d6fca5 | 3531 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3532 | { |
3533 | fgets (buffer, sizeof (buffer), procfile); | |
3534 | printf_filtered ("cmdline = '%s'\n", buffer); | |
3535 | fclose (procfile); | |
3536 | } | |
3537 | else | |
8a3fe4f8 | 3538 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3539 | } |
3540 | if (cwd_f || all) | |
3541 | { | |
3542 | sprintf (fname1, "/proc/%lld/cwd", pid); | |
3543 | memset (fname2, 0, sizeof (fname2)); | |
3544 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3545 | printf_filtered ("cwd = '%s'\n", fname2); | |
3546 | else | |
8a3fe4f8 | 3547 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3548 | } |
3549 | if (exe_f || all) | |
3550 | { | |
3551 | sprintf (fname1, "/proc/%lld/exe", pid); | |
3552 | memset (fname2, 0, sizeof (fname2)); | |
3553 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3554 | printf_filtered ("exe = '%s'\n", fname2); | |
3555 | else | |
8a3fe4f8 | 3556 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3557 | } |
3558 | if (mappings_f || all) | |
3559 | { | |
3560 | sprintf (fname1, "/proc/%lld/maps", pid); | |
d5d6fca5 | 3561 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3562 | { |
3563 | long long addr, endaddr, size, offset, inode; | |
3564 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3565 | ||
a3f17187 | 3566 | printf_filtered (_("Mapped address spaces:\n\n")); |
17a912b6 | 3567 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3568 | { |
3569 | printf_filtered ("\t%10s %10s %10s %10s %7s\n", | |
3570 | "Start Addr", | |
3571 | " End Addr", | |
3572 | " Size", " Offset", "objfile"); | |
3573 | } | |
3574 | else | |
3575 | { | |
3576 | printf_filtered (" %18s %18s %10s %10s %7s\n", | |
3577 | "Start Addr", | |
3578 | " End Addr", | |
3579 | " Size", " Offset", "objfile"); | |
3580 | } | |
3581 | ||
3582 | while (read_mapping (procfile, &addr, &endaddr, &permissions[0], | |
3583 | &offset, &device[0], &inode, &filename[0])) | |
3584 | { | |
3585 | size = endaddr - addr; | |
3586 | ||
3587 | /* FIXME: carlton/2003-08-27: Maybe the printf_filtered | |
3588 | calls here (and possibly above) should be abstracted | |
3589 | out into their own functions? Andrew suggests using | |
3590 | a generic local_address_string instead to print out | |
3591 | the addresses; that makes sense to me, too. */ | |
3592 | ||
17a912b6 | 3593 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3594 | { |
3595 | printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n", | |
3596 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3597 | (unsigned long) endaddr, | |
3598 | (int) size, | |
3599 | (unsigned int) offset, | |
3600 | filename[0] ? filename : ""); | |
3601 | } | |
3602 | else | |
3603 | { | |
3604 | printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n", | |
3605 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3606 | (unsigned long) endaddr, | |
3607 | (int) size, | |
3608 | (unsigned int) offset, | |
3609 | filename[0] ? filename : ""); | |
3610 | } | |
3611 | } | |
3612 | ||
3613 | fclose (procfile); | |
3614 | } | |
3615 | else | |
8a3fe4f8 | 3616 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3617 | } |
3618 | if (status_f || all) | |
3619 | { | |
3620 | sprintf (fname1, "/proc/%lld/status", pid); | |
d5d6fca5 | 3621 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3622 | { |
3623 | while (fgets (buffer, sizeof (buffer), procfile) != NULL) | |
3624 | puts_filtered (buffer); | |
3625 | fclose (procfile); | |
3626 | } | |
3627 | else | |
8a3fe4f8 | 3628 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3629 | } |
3630 | if (stat_f || all) | |
3631 | { | |
3632 | sprintf (fname1, "/proc/%lld/stat", pid); | |
d5d6fca5 | 3633 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3634 | { |
3635 | int itmp; | |
3636 | char ctmp; | |
a25694b4 | 3637 | long ltmp; |
dba24537 AC |
3638 | |
3639 | if (fscanf (procfile, "%d ", &itmp) > 0) | |
a3f17187 | 3640 | printf_filtered (_("Process: %d\n"), itmp); |
a25694b4 | 3641 | if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0) |
a3f17187 | 3642 | printf_filtered (_("Exec file: %s\n"), buffer); |
dba24537 | 3643 | if (fscanf (procfile, "%c ", &ctmp) > 0) |
a3f17187 | 3644 | printf_filtered (_("State: %c\n"), ctmp); |
dba24537 | 3645 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3646 | printf_filtered (_("Parent process: %d\n"), itmp); |
dba24537 | 3647 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3648 | printf_filtered (_("Process group: %d\n"), itmp); |
dba24537 | 3649 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3650 | printf_filtered (_("Session id: %d\n"), itmp); |
dba24537 | 3651 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3652 | printf_filtered (_("TTY: %d\n"), itmp); |
dba24537 | 3653 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3654 | printf_filtered (_("TTY owner process group: %d\n"), itmp); |
a25694b4 AS |
3655 | if (fscanf (procfile, "%lu ", <mp) > 0) |
3656 | printf_filtered (_("Flags: 0x%lx\n"), ltmp); | |
3657 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3658 | printf_filtered (_("Minor faults (no memory page): %lu\n"), | |
3659 | (unsigned long) ltmp); | |
3660 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3661 | printf_filtered (_("Minor faults, children: %lu\n"), | |
3662 | (unsigned long) ltmp); | |
3663 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3664 | printf_filtered (_("Major faults (memory page faults): %lu\n"), | |
3665 | (unsigned long) ltmp); | |
3666 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3667 | printf_filtered (_("Major faults, children: %lu\n"), | |
3668 | (unsigned long) ltmp); | |
3669 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3670 | printf_filtered (_("utime: %ld\n"), ltmp); | |
3671 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3672 | printf_filtered (_("stime: %ld\n"), ltmp); | |
3673 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3674 | printf_filtered (_("utime, children: %ld\n"), ltmp); | |
3675 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3676 | printf_filtered (_("stime, children: %ld\n"), ltmp); | |
3677 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3678 | printf_filtered (_("jiffies remaining in current time slice: %ld\n"), | |
3679 | ltmp); | |
3680 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3681 | printf_filtered (_("'nice' value: %ld\n"), ltmp); | |
3682 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3683 | printf_filtered (_("jiffies until next timeout: %lu\n"), | |
3684 | (unsigned long) ltmp); | |
3685 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3686 | printf_filtered (_("jiffies until next SIGALRM: %lu\n"), | |
3687 | (unsigned long) ltmp); | |
3688 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3689 | printf_filtered (_("start time (jiffies since system boot): %ld\n"), | |
3690 | ltmp); | |
3691 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3692 | printf_filtered (_("Virtual memory size: %lu\n"), | |
3693 | (unsigned long) ltmp); | |
3694 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3695 | printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp); | |
3696 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3697 | printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp); | |
3698 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3699 | printf_filtered (_("Start of text: 0x%lx\n"), ltmp); | |
3700 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3701 | printf_filtered (_("End of text: 0x%lx\n"), ltmp); | |
3702 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3703 | printf_filtered (_("Start of stack: 0x%lx\n"), ltmp); | |
dba24537 AC |
3704 | #if 0 /* Don't know how architecture-dependent the rest is... |
3705 | Anyway the signal bitmap info is available from "status". */ | |
a25694b4 AS |
3706 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ |
3707 | printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp); | |
3708 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3709 | printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp); | |
3710 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3711 | printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp); | |
3712 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3713 | printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp); | |
3714 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3715 | printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp); | |
3716 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3717 | printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp); | |
3718 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3719 | printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp); | |
dba24537 AC |
3720 | #endif |
3721 | fclose (procfile); | |
3722 | } | |
3723 | else | |
8a3fe4f8 | 3724 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3725 | } |
3726 | } | |
3727 | ||
10d6c8cd DJ |
3728 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
3729 | filesystem. Because we can use a single read() call for /proc, this | |
3730 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
3731 | but it doesn't support writes. */ | |
3732 | ||
3733 | static LONGEST | |
3734 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, | |
3735 | const char *annex, gdb_byte *readbuf, | |
3736 | const gdb_byte *writebuf, | |
3737 | ULONGEST offset, LONGEST len) | |
dba24537 | 3738 | { |
10d6c8cd DJ |
3739 | LONGEST ret; |
3740 | int fd; | |
dba24537 AC |
3741 | char filename[64]; |
3742 | ||
10d6c8cd | 3743 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
3744 | return 0; |
3745 | ||
3746 | /* Don't bother for one word. */ | |
3747 | if (len < 3 * sizeof (long)) | |
3748 | return 0; | |
3749 | ||
3750 | /* We could keep this file open and cache it - possibly one per | |
3751 | thread. That requires some juggling, but is even faster. */ | |
3752 | sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid)); | |
3753 | fd = open (filename, O_RDONLY | O_LARGEFILE); | |
3754 | if (fd == -1) | |
3755 | return 0; | |
3756 | ||
3757 | /* If pread64 is available, use it. It's faster if the kernel | |
3758 | supports it (only one syscall), and it's 64-bit safe even on | |
3759 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
3760 | application). */ | |
3761 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 3762 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 3763 | #else |
10d6c8cd | 3764 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
3765 | #endif |
3766 | ret = 0; | |
3767 | else | |
3768 | ret = len; | |
3769 | ||
3770 | close (fd); | |
3771 | return ret; | |
3772 | } | |
3773 | ||
3774 | /* Parse LINE as a signal set and add its set bits to SIGS. */ | |
3775 | ||
3776 | static void | |
3777 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
3778 | { | |
3779 | int len = strlen (line) - 1; | |
3780 | const char *p; | |
3781 | int signum; | |
3782 | ||
3783 | if (line[len] != '\n') | |
8a3fe4f8 | 3784 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3785 | |
3786 | p = line; | |
3787 | signum = len * 4; | |
3788 | while (len-- > 0) | |
3789 | { | |
3790 | int digit; | |
3791 | ||
3792 | if (*p >= '0' && *p <= '9') | |
3793 | digit = *p - '0'; | |
3794 | else if (*p >= 'a' && *p <= 'f') | |
3795 | digit = *p - 'a' + 10; | |
3796 | else | |
8a3fe4f8 | 3797 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3798 | |
3799 | signum -= 4; | |
3800 | ||
3801 | if (digit & 1) | |
3802 | sigaddset (sigs, signum + 1); | |
3803 | if (digit & 2) | |
3804 | sigaddset (sigs, signum + 2); | |
3805 | if (digit & 4) | |
3806 | sigaddset (sigs, signum + 3); | |
3807 | if (digit & 8) | |
3808 | sigaddset (sigs, signum + 4); | |
3809 | ||
3810 | p++; | |
3811 | } | |
3812 | } | |
3813 | ||
3814 | /* Find process PID's pending signals from /proc/pid/status and set | |
3815 | SIGS to match. */ | |
3816 | ||
3817 | void | |
3818 | linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigset_t *ignored) | |
3819 | { | |
3820 | FILE *procfile; | |
3821 | char buffer[MAXPATHLEN], fname[MAXPATHLEN]; | |
3822 | int signum; | |
3823 | ||
3824 | sigemptyset (pending); | |
3825 | sigemptyset (blocked); | |
3826 | sigemptyset (ignored); | |
3827 | sprintf (fname, "/proc/%d/status", pid); | |
3828 | procfile = fopen (fname, "r"); | |
3829 | if (procfile == NULL) | |
8a3fe4f8 | 3830 | error (_("Could not open %s"), fname); |
dba24537 AC |
3831 | |
3832 | while (fgets (buffer, MAXPATHLEN, procfile) != NULL) | |
3833 | { | |
3834 | /* Normal queued signals are on the SigPnd line in the status | |
3835 | file. However, 2.6 kernels also have a "shared" pending | |
3836 | queue for delivering signals to a thread group, so check for | |
3837 | a ShdPnd line also. | |
3838 | ||
3839 | Unfortunately some Red Hat kernels include the shared pending | |
3840 | queue but not the ShdPnd status field. */ | |
3841 | ||
3842 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
3843 | add_line_to_sigset (buffer + 8, pending); | |
3844 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
3845 | add_line_to_sigset (buffer + 8, pending); | |
3846 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
3847 | add_line_to_sigset (buffer + 8, blocked); | |
3848 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
3849 | add_line_to_sigset (buffer + 8, ignored); | |
3850 | } | |
3851 | ||
3852 | fclose (procfile); | |
3853 | } | |
3854 | ||
10d6c8cd DJ |
3855 | static LONGEST |
3856 | linux_xfer_partial (struct target_ops *ops, enum target_object object, | |
3857 | const char *annex, gdb_byte *readbuf, | |
3858 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
3859 | { | |
3860 | LONGEST xfer; | |
3861 | ||
3862 | if (object == TARGET_OBJECT_AUXV) | |
3863 | return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf, | |
3864 | offset, len); | |
3865 | ||
3866 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3867 | offset, len); | |
3868 | if (xfer != 0) | |
3869 | return xfer; | |
3870 | ||
3871 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3872 | offset, len); | |
3873 | } | |
3874 | ||
e9efe249 | 3875 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
3876 | it with local methods. */ |
3877 | ||
910122bf UW |
3878 | static void |
3879 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 3880 | { |
6d8fd2b7 UW |
3881 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
3882 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; | |
3883 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; | |
3884 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; | |
10d6c8cd | 3885 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
3886 | t->to_post_attach = linux_child_post_attach; |
3887 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
3888 | t->to_find_memory_regions = linux_nat_find_memory_regions; |
3889 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; | |
3890 | ||
3891 | super_xfer_partial = t->to_xfer_partial; | |
3892 | t->to_xfer_partial = linux_xfer_partial; | |
910122bf UW |
3893 | } |
3894 | ||
3895 | struct target_ops * | |
3896 | linux_target (void) | |
3897 | { | |
3898 | struct target_ops *t; | |
3899 | ||
3900 | t = inf_ptrace_target (); | |
3901 | linux_target_install_ops (t); | |
3902 | ||
3903 | return t; | |
3904 | } | |
3905 | ||
3906 | struct target_ops * | |
7714d83a | 3907 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
3908 | { |
3909 | struct target_ops *t; | |
3910 | ||
3911 | t = inf_ptrace_trad_target (register_u_offset); | |
3912 | linux_target_install_ops (t); | |
10d6c8cd | 3913 | |
10d6c8cd DJ |
3914 | return t; |
3915 | } | |
3916 | ||
b84876c2 PA |
3917 | /* Controls if async mode is permitted. */ |
3918 | static int linux_async_permitted = 0; | |
3919 | ||
3920 | /* The set command writes to this variable. If the inferior is | |
3921 | executing, linux_nat_async_permitted is *not* updated. */ | |
3922 | static int linux_async_permitted_1 = 0; | |
3923 | ||
3924 | static void | |
3925 | set_maintenance_linux_async_permitted (char *args, int from_tty, | |
3926 | struct cmd_list_element *c) | |
3927 | { | |
3928 | if (target_has_execution) | |
3929 | { | |
3930 | linux_async_permitted_1 = linux_async_permitted; | |
3931 | error (_("Cannot change this setting while the inferior is running.")); | |
3932 | } | |
3933 | ||
3934 | linux_async_permitted = linux_async_permitted_1; | |
3935 | linux_nat_set_async_mode (linux_async_permitted); | |
3936 | } | |
3937 | ||
3938 | static void | |
3939 | show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty, | |
3940 | struct cmd_list_element *c, const char *value) | |
3941 | { | |
3942 | fprintf_filtered (file, _("\ | |
3943 | Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"), | |
3944 | value); | |
3945 | } | |
3946 | ||
3947 | /* target_is_async_p implementation. */ | |
3948 | ||
3949 | static int | |
3950 | linux_nat_is_async_p (void) | |
3951 | { | |
3952 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
3953 | it explicitly with the "maintenance set linux-async" command. | |
3954 | Someday, linux will always be async. */ | |
3955 | if (!linux_async_permitted) | |
3956 | return 0; | |
3957 | ||
3958 | return 1; | |
3959 | } | |
3960 | ||
3961 | /* target_can_async_p implementation. */ | |
3962 | ||
3963 | static int | |
3964 | linux_nat_can_async_p (void) | |
3965 | { | |
3966 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
3967 | it explicitly with the "maintenance set linux-async" command. | |
3968 | Someday, linux will always be async. */ | |
3969 | if (!linux_async_permitted) | |
3970 | return 0; | |
3971 | ||
3972 | /* See target.h/target_async_mask. */ | |
3973 | return linux_nat_async_mask_value; | |
3974 | } | |
3975 | ||
3976 | /* target_async_mask implementation. */ | |
3977 | ||
3978 | static int | |
3979 | linux_nat_async_mask (int mask) | |
3980 | { | |
3981 | int current_state; | |
3982 | current_state = linux_nat_async_mask_value; | |
3983 | ||
3984 | if (current_state != mask) | |
3985 | { | |
3986 | if (mask == 0) | |
3987 | { | |
3988 | linux_nat_async (NULL, 0); | |
3989 | linux_nat_async_mask_value = mask; | |
b84876c2 PA |
3990 | } |
3991 | else | |
3992 | { | |
b84876c2 PA |
3993 | linux_nat_async_mask_value = mask; |
3994 | linux_nat_async (inferior_event_handler, 0); | |
3995 | } | |
3996 | } | |
3997 | ||
3998 | return current_state; | |
3999 | } | |
4000 | ||
4001 | /* Pop an event from the event pipe. */ | |
4002 | ||
4003 | static int | |
4004 | linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options) | |
4005 | { | |
4006 | struct waitpid_result event = {0}; | |
4007 | int ret; | |
4008 | ||
4009 | do | |
4010 | { | |
4011 | ret = read (linux_nat_event_pipe[0], &event, sizeof (event)); | |
4012 | } | |
4013 | while (ret == -1 && errno == EINTR); | |
4014 | ||
4015 | gdb_assert (ret == sizeof (event)); | |
4016 | ||
4017 | *ptr_status = event.status; | |
4018 | *ptr_options = event.options; | |
4019 | ||
4020 | linux_nat_num_queued_events--; | |
4021 | ||
4022 | return event.pid; | |
4023 | } | |
4024 | ||
4025 | /* Push an event into the event pipe. */ | |
4026 | ||
4027 | static void | |
4028 | linux_nat_event_pipe_push (int pid, int status, int options) | |
4029 | { | |
4030 | int ret; | |
4031 | struct waitpid_result event = {0}; | |
4032 | event.pid = pid; | |
4033 | event.status = status; | |
4034 | event.options = options; | |
4035 | ||
4036 | do | |
4037 | { | |
4038 | ret = write (linux_nat_event_pipe[1], &event, sizeof (event)); | |
4039 | gdb_assert ((ret == -1 && errno == EINTR) || ret == sizeof (event)); | |
4040 | } while (ret == -1 && errno == EINTR); | |
4041 | ||
4042 | linux_nat_num_queued_events++; | |
4043 | } | |
4044 | ||
4045 | static void | |
4046 | get_pending_events (void) | |
4047 | { | |
4048 | int status, options, pid; | |
4049 | ||
84e46146 PA |
4050 | if (!linux_nat_async_enabled |
4051 | || linux_nat_async_events_state != sigchld_async) | |
b84876c2 PA |
4052 | internal_error (__FILE__, __LINE__, |
4053 | "get_pending_events called with async masked"); | |
4054 | ||
4055 | while (1) | |
4056 | { | |
4057 | status = 0; | |
4058 | options = __WCLONE | WNOHANG; | |
4059 | ||
4060 | do | |
4061 | { | |
4062 | pid = waitpid (-1, &status, options); | |
4063 | } | |
4064 | while (pid == -1 && errno == EINTR); | |
4065 | ||
4066 | if (pid <= 0) | |
4067 | { | |
4068 | options = WNOHANG; | |
4069 | do | |
4070 | { | |
4071 | pid = waitpid (-1, &status, options); | |
4072 | } | |
4073 | while (pid == -1 && errno == EINTR); | |
4074 | } | |
4075 | ||
4076 | if (pid <= 0) | |
4077 | /* No more children reporting events. */ | |
4078 | break; | |
4079 | ||
4080 | if (debug_linux_nat_async) | |
4081 | fprintf_unfiltered (gdb_stdlog, "\ | |
4082 | get_pending_events: pid(%d), status(%x), options (%x)\n", | |
4083 | pid, status, options); | |
4084 | ||
4085 | linux_nat_event_pipe_push (pid, status, options); | |
4086 | } | |
4087 | ||
4088 | if (debug_linux_nat_async) | |
4089 | fprintf_unfiltered (gdb_stdlog, "\ | |
4090 | get_pending_events: linux_nat_num_queued_events(%d)\n", | |
4091 | linux_nat_num_queued_events); | |
4092 | } | |
4093 | ||
4094 | /* SIGCHLD handler for async mode. */ | |
4095 | ||
4096 | static void | |
4097 | async_sigchld_handler (int signo) | |
4098 | { | |
4099 | if (debug_linux_nat_async) | |
4100 | fprintf_unfiltered (gdb_stdlog, "async_sigchld_handler\n"); | |
4101 | ||
4102 | get_pending_events (); | |
4103 | } | |
4104 | ||
84e46146 | 4105 | /* Set SIGCHLD handling state to STATE. Returns previous state. */ |
b84876c2 | 4106 | |
84e46146 PA |
4107 | static enum sigchld_state |
4108 | linux_nat_async_events (enum sigchld_state state) | |
b84876c2 | 4109 | { |
84e46146 | 4110 | enum sigchld_state current_state = linux_nat_async_events_state; |
b84876c2 PA |
4111 | |
4112 | if (debug_linux_nat_async) | |
4113 | fprintf_unfiltered (gdb_stdlog, | |
84e46146 | 4114 | "LNAE: state(%d): linux_nat_async_events_state(%d), " |
b84876c2 | 4115 | "linux_nat_num_queued_events(%d)\n", |
84e46146 | 4116 | state, linux_nat_async_events_state, |
b84876c2 PA |
4117 | linux_nat_num_queued_events); |
4118 | ||
84e46146 | 4119 | if (current_state != state) |
b84876c2 PA |
4120 | { |
4121 | sigset_t mask; | |
4122 | sigemptyset (&mask); | |
4123 | sigaddset (&mask, SIGCHLD); | |
84e46146 PA |
4124 | |
4125 | /* Always block before changing state. */ | |
4126 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4127 | ||
4128 | /* Set new state. */ | |
4129 | linux_nat_async_events_state = state; | |
4130 | ||
4131 | switch (state) | |
b84876c2 | 4132 | { |
84e46146 PA |
4133 | case sigchld_sync: |
4134 | { | |
4135 | /* Block target events. */ | |
4136 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4137 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
4138 | /* Get events out of queue, and make them available to | |
4139 | queued_waitpid / my_waitpid. */ | |
4140 | pipe_to_local_event_queue (); | |
4141 | } | |
4142 | break; | |
4143 | case sigchld_async: | |
4144 | { | |
4145 | /* Unblock target events for async mode. */ | |
4146 | ||
4147 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4148 | ||
4149 | /* Put events we already waited on, in the pipe first, so | |
4150 | events are FIFO. */ | |
4151 | local_event_queue_to_pipe (); | |
4152 | /* While in masked async, we may have not collected all | |
4153 | the pending events. Get them out now. */ | |
4154 | get_pending_events (); | |
4155 | ||
4156 | /* Let'em come. */ | |
4157 | sigaction (SIGCHLD, &async_sigchld_action, NULL); | |
4158 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
4159 | } | |
4160 | break; | |
4161 | case sigchld_default: | |
4162 | { | |
4163 | /* SIGCHLD default mode. */ | |
4164 | sigaction (SIGCHLD, &sigchld_default_action, NULL); | |
4165 | ||
4166 | /* Get events out of queue, and make them available to | |
4167 | queued_waitpid / my_waitpid. */ | |
4168 | pipe_to_local_event_queue (); | |
4169 | ||
4170 | /* Unblock SIGCHLD. */ | |
4171 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
4172 | } | |
4173 | break; | |
b84876c2 PA |
4174 | } |
4175 | } | |
4176 | ||
4177 | return current_state; | |
4178 | } | |
4179 | ||
4180 | static int async_terminal_is_ours = 1; | |
4181 | ||
4182 | /* target_terminal_inferior implementation. */ | |
4183 | ||
4184 | static void | |
4185 | linux_nat_terminal_inferior (void) | |
4186 | { | |
4187 | if (!target_is_async_p ()) | |
4188 | { | |
4189 | /* Async mode is disabled. */ | |
4190 | terminal_inferior (); | |
4191 | return; | |
4192 | } | |
4193 | ||
4194 | /* GDB should never give the terminal to the inferior, if the | |
4195 | inferior is running in the background (run&, continue&, etc.). | |
4196 | This check can be removed when the common code is fixed. */ | |
4197 | if (!sync_execution) | |
4198 | return; | |
4199 | ||
4200 | terminal_inferior (); | |
4201 | ||
4202 | if (!async_terminal_is_ours) | |
4203 | return; | |
4204 | ||
4205 | delete_file_handler (input_fd); | |
4206 | async_terminal_is_ours = 0; | |
4207 | set_sigint_trap (); | |
4208 | } | |
4209 | ||
4210 | /* target_terminal_ours implementation. */ | |
4211 | ||
4212 | void | |
4213 | linux_nat_terminal_ours (void) | |
4214 | { | |
4215 | if (!target_is_async_p ()) | |
4216 | { | |
4217 | /* Async mode is disabled. */ | |
4218 | terminal_ours (); | |
4219 | return; | |
4220 | } | |
4221 | ||
4222 | /* GDB should never give the terminal to the inferior if the | |
4223 | inferior is running in the background (run&, continue&, etc.), | |
4224 | but claiming it sure should. */ | |
4225 | terminal_ours (); | |
4226 | ||
4227 | if (!sync_execution) | |
4228 | return; | |
4229 | ||
4230 | if (async_terminal_is_ours) | |
4231 | return; | |
4232 | ||
4233 | clear_sigint_trap (); | |
4234 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4235 | async_terminal_is_ours = 1; | |
4236 | } | |
4237 | ||
4238 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4239 | void *context); | |
4240 | static void *async_client_context; | |
4241 | ||
4242 | static void | |
4243 | linux_nat_async_file_handler (int error, gdb_client_data client_data) | |
4244 | { | |
4245 | async_client_callback (INF_REG_EVENT, async_client_context); | |
4246 | } | |
4247 | ||
4248 | /* target_async implementation. */ | |
4249 | ||
4250 | static void | |
4251 | linux_nat_async (void (*callback) (enum inferior_event_type event_type, | |
4252 | void *context), void *context) | |
4253 | { | |
4254 | if (linux_nat_async_mask_value == 0 || !linux_nat_async_enabled) | |
4255 | internal_error (__FILE__, __LINE__, | |
4256 | "Calling target_async when async is masked"); | |
4257 | ||
4258 | if (callback != NULL) | |
4259 | { | |
4260 | async_client_callback = callback; | |
4261 | async_client_context = context; | |
4262 | add_file_handler (linux_nat_event_pipe[0], | |
4263 | linux_nat_async_file_handler, NULL); | |
4264 | ||
84e46146 | 4265 | linux_nat_async_events (sigchld_async); |
b84876c2 PA |
4266 | } |
4267 | else | |
4268 | { | |
4269 | async_client_callback = callback; | |
4270 | async_client_context = context; | |
4271 | ||
84e46146 | 4272 | linux_nat_async_events (sigchld_sync); |
b84876c2 PA |
4273 | delete_file_handler (linux_nat_event_pipe[0]); |
4274 | } | |
4275 | return; | |
4276 | } | |
4277 | ||
4278 | /* Enable/Disable async mode. */ | |
4279 | ||
4280 | static void | |
4281 | linux_nat_set_async_mode (int on) | |
4282 | { | |
4283 | if (linux_nat_async_enabled != on) | |
4284 | { | |
4285 | if (on) | |
4286 | { | |
4287 | gdb_assert (waitpid_queue == NULL); | |
b84876c2 PA |
4288 | if (pipe (linux_nat_event_pipe) == -1) |
4289 | internal_error (__FILE__, __LINE__, | |
4290 | "creating event pipe failed."); | |
b84876c2 PA |
4291 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); |
4292 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4293 | } | |
4294 | else | |
4295 | { | |
b84876c2 | 4296 | drain_queued_events (-1); |
b84876c2 PA |
4297 | linux_nat_num_queued_events = 0; |
4298 | close (linux_nat_event_pipe[0]); | |
4299 | close (linux_nat_event_pipe[1]); | |
4300 | linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1; | |
4301 | ||
4302 | } | |
4303 | } | |
4304 | linux_nat_async_enabled = on; | |
4305 | } | |
4306 | ||
f973ed9c DJ |
4307 | void |
4308 | linux_nat_add_target (struct target_ops *t) | |
4309 | { | |
f973ed9c DJ |
4310 | /* Save the provided single-threaded target. We save this in a separate |
4311 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4312 | may have saved a pointer to T; we want to use it for the final | |
4313 | process stratum target. */ | |
4314 | linux_ops_saved = *t; | |
4315 | linux_ops = &linux_ops_saved; | |
4316 | ||
4317 | /* Override some methods for multithreading. */ | |
b84876c2 | 4318 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4319 | t->to_attach = linux_nat_attach; |
4320 | t->to_detach = linux_nat_detach; | |
4321 | t->to_resume = linux_nat_resume; | |
4322 | t->to_wait = linux_nat_wait; | |
4323 | t->to_xfer_partial = linux_nat_xfer_partial; | |
4324 | t->to_kill = linux_nat_kill; | |
4325 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4326 | t->to_thread_alive = linux_nat_thread_alive; | |
4327 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4328 | t->to_has_thread_control = tc_schedlock; | |
4329 | ||
b84876c2 PA |
4330 | t->to_can_async_p = linux_nat_can_async_p; |
4331 | t->to_is_async_p = linux_nat_is_async_p; | |
4332 | t->to_async = linux_nat_async; | |
4333 | t->to_async_mask = linux_nat_async_mask; | |
4334 | t->to_terminal_inferior = linux_nat_terminal_inferior; | |
4335 | t->to_terminal_ours = linux_nat_terminal_ours; | |
4336 | ||
f973ed9c DJ |
4337 | /* We don't change the stratum; this target will sit at |
4338 | process_stratum and thread_db will set at thread_stratum. This | |
4339 | is a little strange, since this is a multi-threaded-capable | |
4340 | target, but we want to be on the stack below thread_db, and we | |
4341 | also want to be used for single-threaded processes. */ | |
4342 | ||
4343 | add_target (t); | |
4344 | ||
4345 | /* TODO: Eliminate this and have libthread_db use | |
4346 | find_target_beneath. */ | |
4347 | thread_db_init (t); | |
4348 | } | |
4349 | ||
9f0bdab8 DJ |
4350 | /* Register a method to call whenever a new thread is attached. */ |
4351 | void | |
4352 | linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t)) | |
4353 | { | |
4354 | /* Save the pointer. We only support a single registered instance | |
4355 | of the GNU/Linux native target, so we do not need to map this to | |
4356 | T. */ | |
4357 | linux_nat_new_thread = new_thread; | |
4358 | } | |
4359 | ||
4360 | /* Return the saved siginfo associated with PTID. */ | |
4361 | struct siginfo * | |
4362 | linux_nat_get_siginfo (ptid_t ptid) | |
4363 | { | |
4364 | struct lwp_info *lp = find_lwp_pid (ptid); | |
4365 | ||
4366 | gdb_assert (lp != NULL); | |
4367 | ||
4368 | return &lp->siginfo; | |
4369 | } | |
4370 | ||
d6b0e80f AC |
4371 | void |
4372 | _initialize_linux_nat (void) | |
4373 | { | |
b84876c2 | 4374 | sigset_t mask; |
dba24537 | 4375 | |
1bedd215 AC |
4376 | add_info ("proc", linux_nat_info_proc_cmd, _("\ |
4377 | Show /proc process information about any running process.\n\ | |
dba24537 AC |
4378 | Specify any process id, or use the program being debugged by default.\n\ |
4379 | Specify any of the following keywords for detailed info:\n\ | |
4380 | mappings -- list of mapped memory regions.\n\ | |
4381 | stat -- list a bunch of random process info.\n\ | |
4382 | status -- list a different bunch of random process info.\n\ | |
1bedd215 | 4383 | all -- list all available /proc info.")); |
d6b0e80f | 4384 | |
b84876c2 PA |
4385 | add_setshow_zinteger_cmd ("lin-lwp", class_maintenance, |
4386 | &debug_linux_nat, _("\ | |
4387 | Set debugging of GNU/Linux lwp module."), _("\ | |
4388 | Show debugging of GNU/Linux lwp module."), _("\ | |
4389 | Enables printf debugging output."), | |
4390 | NULL, | |
4391 | show_debug_linux_nat, | |
4392 | &setdebuglist, &showdebuglist); | |
4393 | ||
4394 | add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance, | |
4395 | &debug_linux_nat_async, _("\ | |
4396 | Set debugging of GNU/Linux async lwp module."), _("\ | |
4397 | Show debugging of GNU/Linux async lwp module."), _("\ | |
4398 | Enables printf debugging output."), | |
4399 | NULL, | |
4400 | show_debug_linux_nat_async, | |
4401 | &setdebuglist, &showdebuglist); | |
4402 | ||
4403 | add_setshow_boolean_cmd ("linux-async", class_maintenance, | |
4404 | &linux_async_permitted_1, _("\ | |
4405 | Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4406 | Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4407 | Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."), | |
4408 | set_maintenance_linux_async_permitted, | |
4409 | show_maintenance_linux_async_permitted, | |
4410 | &maintenance_set_cmdlist, | |
4411 | &maintenance_show_cmdlist); | |
4412 | ||
84e46146 PA |
4413 | /* Get the default SIGCHLD action. Used while forking an inferior |
4414 | (see linux_nat_create_inferior/linux_nat_async_events). */ | |
4415 | sigaction (SIGCHLD, NULL, &sigchld_default_action); | |
4416 | ||
b84876c2 PA |
4417 | /* Block SIGCHLD by default. Doing this early prevents it getting |
4418 | unblocked if an exception is thrown due to an error while the | |
4419 | inferior is starting (sigsetjmp/siglongjmp). */ | |
4420 | sigemptyset (&mask); | |
4421 | sigaddset (&mask, SIGCHLD); | |
4422 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4423 | ||
4424 | /* Save this mask as the default. */ | |
d6b0e80f AC |
4425 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4426 | ||
b84876c2 PA |
4427 | /* The synchronous SIGCHLD handler. */ |
4428 | sync_sigchld_action.sa_handler = sigchld_handler; | |
4429 | sigemptyset (&sync_sigchld_action.sa_mask); | |
4430 | sync_sigchld_action.sa_flags = SA_RESTART; | |
4431 | ||
4432 | /* Make it the default. */ | |
4433 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
d6b0e80f AC |
4434 | |
4435 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4436 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4437 | sigdelset (&suspend_mask, SIGCHLD); | |
4438 | ||
b84876c2 PA |
4439 | /* SIGCHLD handler for async mode. */ |
4440 | async_sigchld_action.sa_handler = async_sigchld_handler; | |
4441 | sigemptyset (&async_sigchld_action.sa_mask); | |
4442 | async_sigchld_action.sa_flags = SA_RESTART; | |
d6b0e80f | 4443 | |
b84876c2 PA |
4444 | /* Install the default mode. */ |
4445 | linux_nat_set_async_mode (linux_async_permitted); | |
10568435 JK |
4446 | |
4447 | add_setshow_boolean_cmd ("disable-randomization", class_support, | |
4448 | &disable_randomization, _("\ | |
4449 | Set disabling of debuggee's virtual address space randomization."), _("\ | |
4450 | Show disabling of debuggee's virtual address space randomization."), _("\ | |
4451 | When this mode is on (which is the default), randomization of the virtual\n\ | |
4452 | address space is disabled. Standalone programs run with the randomization\n\ | |
4453 | enabled by default on some platforms."), | |
4454 | &set_disable_randomization, | |
4455 | &show_disable_randomization, | |
4456 | &setlist, &showlist); | |
d6b0e80f AC |
4457 | } |
4458 | \f | |
4459 | ||
4460 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4461 | the GNU/Linux Threads library and therefore doesn't really belong | |
4462 | here. */ | |
4463 | ||
4464 | /* Read variable NAME in the target and return its value if found. | |
4465 | Otherwise return zero. It is assumed that the type of the variable | |
4466 | is `int'. */ | |
4467 | ||
4468 | static int | |
4469 | get_signo (const char *name) | |
4470 | { | |
4471 | struct minimal_symbol *ms; | |
4472 | int signo; | |
4473 | ||
4474 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
4475 | if (ms == NULL) | |
4476 | return 0; | |
4477 | ||
8e70166d | 4478 | if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
4479 | sizeof (signo)) != 0) |
4480 | return 0; | |
4481 | ||
4482 | return signo; | |
4483 | } | |
4484 | ||
4485 | /* Return the set of signals used by the threads library in *SET. */ | |
4486 | ||
4487 | void | |
4488 | lin_thread_get_thread_signals (sigset_t *set) | |
4489 | { | |
4490 | struct sigaction action; | |
4491 | int restart, cancel; | |
b84876c2 | 4492 | sigset_t blocked_mask; |
d6b0e80f | 4493 | |
b84876c2 | 4494 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
4495 | sigemptyset (set); |
4496 | ||
4497 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
4498 | cancel = get_signo ("__pthread_sig_cancel"); |
4499 | ||
4500 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
4501 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
4502 | not provide any way for the debugger to query the signal numbers - | |
4503 | fortunately they don't change! */ | |
4504 | ||
d6b0e80f | 4505 | if (restart == 0) |
17fbb0bd | 4506 | restart = __SIGRTMIN; |
d6b0e80f | 4507 | |
d6b0e80f | 4508 | if (cancel == 0) |
17fbb0bd | 4509 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
4510 | |
4511 | sigaddset (set, restart); | |
4512 | sigaddset (set, cancel); | |
4513 | ||
4514 | /* The GNU/Linux Threads library makes terminating threads send a | |
4515 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
4516 | those (to prevent them from terminating GDB itself, which is | |
4517 | likely to be their default action) and treat them the same way as | |
4518 | SIGCHLD. */ | |
4519 | ||
4520 | action.sa_handler = sigchld_handler; | |
4521 | sigemptyset (&action.sa_mask); | |
58aecb61 | 4522 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
4523 | sigaction (cancel, &action, NULL); |
4524 | ||
4525 | /* We block the "cancel" signal throughout this code ... */ | |
4526 | sigaddset (&blocked_mask, cancel); | |
4527 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
4528 | ||
4529 | /* ... except during a sigsuspend. */ | |
4530 | sigdelset (&suspend_mask, cancel); | |
4531 | } |