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 | |
a0ef4274 DJ |
53 | /* Note on this file's use of signals: |
54 | ||
55 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead | |
56 | of another signal is not entirely significant; we just need for a | |
57 | signal to be delivered, so that we can intercept it. SIGSTOP's | |
58 | advantage is that it can not be blocked. A disadvantage is that it | |
59 | is not a real-time signal, so it can only be queued once; we do not | |
60 | keep track of other sources of SIGSTOP. | |
61 | ||
62 | Two other signals that can't be blocked are SIGCONT and SIGKILL. | |
63 | But we can't use them, because they have special behavior when the | |
64 | signal is generated - not when it is delivered. SIGCONT resumes | |
65 | the entire thread group and SIGKILL kills the entire thread group. | |
66 | ||
67 | A delivered SIGSTOP would stop the entire thread group, not just the | |
68 | thread we tkill'd. But we never let the SIGSTOP deliver; we always | |
69 | intercept and cancel it (by PTRACE_CONT without passing SIGSTOP). | |
70 | ||
71 | We could use a real-time signal instead. This would solve those | |
72 | problems; we could use PTRACE_GETSIGINFO to locate the specific | |
73 | stop signals sent by GDB. But we would still have to have some | |
74 | support for SIGSTOP, since PTRACE_ATTACH generates it, and there | |
75 | are races with trying to find a signal that is not blocked. */ | |
76 | ||
dba24537 AC |
77 | #ifndef O_LARGEFILE |
78 | #define O_LARGEFILE 0 | |
79 | #endif | |
0274a8ce | 80 | |
3993f6b1 DJ |
81 | /* If the system headers did not provide the constants, hard-code the normal |
82 | values. */ | |
83 | #ifndef PTRACE_EVENT_FORK | |
84 | ||
85 | #define PTRACE_SETOPTIONS 0x4200 | |
86 | #define PTRACE_GETEVENTMSG 0x4201 | |
87 | ||
88 | /* options set using PTRACE_SETOPTIONS */ | |
89 | #define PTRACE_O_TRACESYSGOOD 0x00000001 | |
90 | #define PTRACE_O_TRACEFORK 0x00000002 | |
91 | #define PTRACE_O_TRACEVFORK 0x00000004 | |
92 | #define PTRACE_O_TRACECLONE 0x00000008 | |
93 | #define PTRACE_O_TRACEEXEC 0x00000010 | |
9016a515 DJ |
94 | #define PTRACE_O_TRACEVFORKDONE 0x00000020 |
95 | #define PTRACE_O_TRACEEXIT 0x00000040 | |
3993f6b1 DJ |
96 | |
97 | /* Wait extended result codes for the above trace options. */ | |
98 | #define PTRACE_EVENT_FORK 1 | |
99 | #define PTRACE_EVENT_VFORK 2 | |
100 | #define PTRACE_EVENT_CLONE 3 | |
101 | #define PTRACE_EVENT_EXEC 4 | |
c874c7fc | 102 | #define PTRACE_EVENT_VFORK_DONE 5 |
9016a515 | 103 | #define PTRACE_EVENT_EXIT 6 |
3993f6b1 DJ |
104 | |
105 | #endif /* PTRACE_EVENT_FORK */ | |
106 | ||
107 | /* We can't always assume that this flag is available, but all systems | |
108 | with the ptrace event handlers also have __WALL, so it's safe to use | |
109 | here. */ | |
110 | #ifndef __WALL | |
111 | #define __WALL 0x40000000 /* Wait for any child. */ | |
112 | #endif | |
113 | ||
02d3ff8c UW |
114 | #ifndef PTRACE_GETSIGINFO |
115 | #define PTRACE_GETSIGINFO 0x4202 | |
116 | #endif | |
117 | ||
10d6c8cd DJ |
118 | /* The single-threaded native GNU/Linux target_ops. We save a pointer for |
119 | the use of the multi-threaded target. */ | |
120 | static struct target_ops *linux_ops; | |
f973ed9c | 121 | static struct target_ops linux_ops_saved; |
10d6c8cd | 122 | |
9f0bdab8 DJ |
123 | /* The method to call, if any, when a new thread is attached. */ |
124 | static void (*linux_nat_new_thread) (ptid_t); | |
125 | ||
ac264b3b MS |
126 | /* The saved to_xfer_partial method, inherited from inf-ptrace.c. |
127 | Called by our to_xfer_partial. */ | |
128 | static LONGEST (*super_xfer_partial) (struct target_ops *, | |
129 | enum target_object, | |
130 | const char *, gdb_byte *, | |
131 | const gdb_byte *, | |
10d6c8cd DJ |
132 | ULONGEST, LONGEST); |
133 | ||
d6b0e80f | 134 | static int debug_linux_nat; |
920d2a44 AC |
135 | static void |
136 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
137 | struct cmd_list_element *c, const char *value) | |
138 | { | |
139 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
140 | value); | |
141 | } | |
d6b0e80f | 142 | |
b84876c2 PA |
143 | static int debug_linux_nat_async = 0; |
144 | static void | |
145 | show_debug_linux_nat_async (struct ui_file *file, int from_tty, | |
146 | struct cmd_list_element *c, const char *value) | |
147 | { | |
148 | fprintf_filtered (file, _("Debugging of GNU/Linux async lwp module is %s.\n"), | |
149 | value); | |
150 | } | |
151 | ||
9016a515 DJ |
152 | static int linux_parent_pid; |
153 | ||
ae087d01 DJ |
154 | struct simple_pid_list |
155 | { | |
156 | int pid; | |
3d799a95 | 157 | int status; |
ae087d01 DJ |
158 | struct simple_pid_list *next; |
159 | }; | |
160 | struct simple_pid_list *stopped_pids; | |
161 | ||
3993f6b1 DJ |
162 | /* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK |
163 | can not be used, 1 if it can. */ | |
164 | ||
165 | static int linux_supports_tracefork_flag = -1; | |
166 | ||
9016a515 DJ |
167 | /* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have |
168 | PTRACE_O_TRACEVFORKDONE. */ | |
169 | ||
170 | static int linux_supports_tracevforkdone_flag = -1; | |
171 | ||
b84876c2 PA |
172 | /* Async mode support */ |
173 | ||
174 | /* To listen to target events asynchronously, we install a SIGCHLD | |
175 | handler whose duty is to call waitpid (-1, ..., WNOHANG) to get all | |
176 | the pending events into a pipe. Whenever we're ready to handle | |
177 | events asynchronously, this pipe is registered as the waitable file | |
178 | handle in the event loop. When we get to entry target points | |
179 | coming out of the common code (target_wait, target_resume, ...), | |
180 | that are going to call waitpid, we block SIGCHLD signals, and | |
181 | remove all the events placed in the pipe into a local queue. All | |
182 | the subsequent calls to my_waitpid (a waitpid wrapper) check this | |
183 | local queue first. */ | |
184 | ||
185 | /* True if async mode is currently on. */ | |
186 | static int linux_nat_async_enabled; | |
187 | ||
188 | /* Zero if the async mode, although enabled, is masked, which means | |
189 | linux_nat_wait should behave as if async mode was off. */ | |
190 | static int linux_nat_async_mask_value = 1; | |
191 | ||
192 | /* The read/write ends of the pipe registered as waitable file in the | |
193 | event loop. */ | |
194 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
195 | ||
196 | /* Number of queued events in the pipe. */ | |
197 | static volatile int linux_nat_num_queued_events; | |
198 | ||
199 | /* If async mode is on, true if we're listening for events; false if | |
200 | target events are blocked. */ | |
201 | static int linux_nat_async_events_enabled; | |
202 | ||
203 | static int linux_nat_async_events (int enable); | |
204 | static void pipe_to_local_event_queue (void); | |
205 | static void local_event_queue_to_pipe (void); | |
206 | static void linux_nat_event_pipe_push (int pid, int status, int options); | |
207 | static int linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options); | |
208 | static void linux_nat_set_async_mode (int on); | |
209 | static void linux_nat_async (void (*callback) | |
210 | (enum inferior_event_type event_type, void *context), | |
211 | void *context); | |
212 | static int linux_nat_async_mask (int mask); | |
a0ef4274 | 213 | static int kill_lwp (int lwpid, int signo); |
b84876c2 PA |
214 | |
215 | /* Captures the result of a successful waitpid call, along with the | |
216 | options used in that call. */ | |
217 | struct waitpid_result | |
218 | { | |
219 | int pid; | |
220 | int status; | |
221 | int options; | |
222 | struct waitpid_result *next; | |
223 | }; | |
224 | ||
225 | /* A singly-linked list of the results of the waitpid calls performed | |
226 | in the async SIGCHLD handler. */ | |
227 | static struct waitpid_result *waitpid_queue = NULL; | |
228 | ||
229 | static int | |
230 | queued_waitpid (int pid, int *status, int flags) | |
231 | { | |
232 | struct waitpid_result *msg = waitpid_queue, *prev = NULL; | |
233 | ||
234 | if (debug_linux_nat_async) | |
235 | fprintf_unfiltered (gdb_stdlog, | |
236 | "\ | |
237 | QWPID: linux_nat_async_events_enabled(%d), linux_nat_num_queued_events(%d)\n", | |
238 | linux_nat_async_events_enabled, | |
239 | linux_nat_num_queued_events); | |
240 | ||
241 | if (flags & __WALL) | |
242 | { | |
243 | for (; msg; prev = msg, msg = msg->next) | |
244 | if (pid == -1 || pid == msg->pid) | |
245 | break; | |
246 | } | |
247 | else if (flags & __WCLONE) | |
248 | { | |
249 | for (; msg; prev = msg, msg = msg->next) | |
250 | if (msg->options & __WCLONE | |
251 | && (pid == -1 || pid == msg->pid)) | |
252 | break; | |
253 | } | |
254 | else | |
255 | { | |
256 | for (; msg; prev = msg, msg = msg->next) | |
257 | if ((msg->options & __WCLONE) == 0 | |
258 | && (pid == -1 || pid == msg->pid)) | |
259 | break; | |
260 | } | |
261 | ||
262 | if (msg) | |
263 | { | |
264 | int pid; | |
265 | ||
266 | if (prev) | |
267 | prev->next = msg->next; | |
268 | else | |
269 | waitpid_queue = msg->next; | |
270 | ||
271 | msg->next = NULL; | |
272 | if (status) | |
273 | *status = msg->status; | |
274 | pid = msg->pid; | |
275 | ||
276 | if (debug_linux_nat_async) | |
277 | fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n", | |
278 | pid, msg->status); | |
279 | xfree (msg); | |
280 | ||
281 | return pid; | |
282 | } | |
283 | ||
284 | if (debug_linux_nat_async) | |
285 | fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n"); | |
286 | ||
287 | if (status) | |
288 | *status = 0; | |
289 | return -1; | |
290 | } | |
291 | ||
292 | static void | |
293 | push_waitpid (int pid, int status, int options) | |
294 | { | |
295 | struct waitpid_result *event, *new_event; | |
296 | ||
297 | new_event = xmalloc (sizeof (*new_event)); | |
298 | new_event->pid = pid; | |
299 | new_event->status = status; | |
300 | new_event->options = options; | |
301 | new_event->next = NULL; | |
302 | ||
303 | if (waitpid_queue) | |
304 | { | |
305 | for (event = waitpid_queue; | |
306 | event && event->next; | |
307 | event = event->next) | |
308 | ; | |
309 | ||
310 | event->next = new_event; | |
311 | } | |
312 | else | |
313 | waitpid_queue = new_event; | |
314 | } | |
315 | ||
710151dd | 316 | /* Drain all queued events of PID. If PID is -1, the effect is of |
b84876c2 PA |
317 | draining all events. */ |
318 | static void | |
319 | drain_queued_events (int pid) | |
320 | { | |
321 | while (queued_waitpid (pid, NULL, __WALL) != -1) | |
322 | ; | |
323 | } | |
324 | ||
ae087d01 DJ |
325 | \f |
326 | /* Trivial list manipulation functions to keep track of a list of | |
327 | new stopped processes. */ | |
328 | static void | |
3d799a95 | 329 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 DJ |
330 | { |
331 | struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list)); | |
332 | new_pid->pid = pid; | |
3d799a95 | 333 | new_pid->status = status; |
ae087d01 DJ |
334 | new_pid->next = *listp; |
335 | *listp = new_pid; | |
336 | } | |
337 | ||
338 | static int | |
3d799a95 | 339 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *status) |
ae087d01 DJ |
340 | { |
341 | struct simple_pid_list **p; | |
342 | ||
343 | for (p = listp; *p != NULL; p = &(*p)->next) | |
344 | if ((*p)->pid == pid) | |
345 | { | |
346 | struct simple_pid_list *next = (*p)->next; | |
3d799a95 | 347 | *status = (*p)->status; |
ae087d01 DJ |
348 | xfree (*p); |
349 | *p = next; | |
350 | return 1; | |
351 | } | |
352 | return 0; | |
353 | } | |
354 | ||
3d799a95 DJ |
355 | static void |
356 | linux_record_stopped_pid (int pid, int status) | |
ae087d01 | 357 | { |
3d799a95 | 358 | add_to_pid_list (&stopped_pids, pid, status); |
ae087d01 DJ |
359 | } |
360 | ||
3993f6b1 DJ |
361 | \f |
362 | /* A helper function for linux_test_for_tracefork, called after fork (). */ | |
363 | ||
364 | static void | |
365 | linux_tracefork_child (void) | |
366 | { | |
367 | int ret; | |
368 | ||
369 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
370 | kill (getpid (), SIGSTOP); | |
371 | fork (); | |
48bb3cce | 372 | _exit (0); |
3993f6b1 DJ |
373 | } |
374 | ||
b84876c2 PA |
375 | /* Wrapper function for waitpid which handles EINTR, and checks for |
376 | locally queued events. */ | |
b957e937 DJ |
377 | |
378 | static int | |
379 | my_waitpid (int pid, int *status, int flags) | |
380 | { | |
381 | int ret; | |
b84876c2 PA |
382 | |
383 | /* There should be no concurrent calls to waitpid. */ | |
384 | gdb_assert (!linux_nat_async_events_enabled); | |
385 | ||
386 | ret = queued_waitpid (pid, status, flags); | |
387 | if (ret != -1) | |
388 | return ret; | |
389 | ||
b957e937 DJ |
390 | do |
391 | { | |
392 | ret = waitpid (pid, status, flags); | |
393 | } | |
394 | while (ret == -1 && errno == EINTR); | |
395 | ||
396 | return ret; | |
397 | } | |
398 | ||
399 | /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. | |
400 | ||
401 | First, we try to enable fork tracing on ORIGINAL_PID. If this fails, | |
402 | we know that the feature is not available. This may change the tracing | |
403 | options for ORIGINAL_PID, but we'll be setting them shortly anyway. | |
404 | ||
405 | However, if it succeeds, we don't know for sure that the feature is | |
406 | available; old versions of PTRACE_SETOPTIONS ignored unknown options. We | |
3993f6b1 | 407 | create a child process, attach to it, use PTRACE_SETOPTIONS to enable |
b957e937 DJ |
408 | fork tracing, and let it fork. If the process exits, we assume that we |
409 | can't use TRACEFORK; if we get the fork notification, and we can extract | |
410 | the new child's PID, then we assume that we can. */ | |
3993f6b1 DJ |
411 | |
412 | static void | |
b957e937 | 413 | linux_test_for_tracefork (int original_pid) |
3993f6b1 DJ |
414 | { |
415 | int child_pid, ret, status; | |
416 | long second_pid; | |
417 | ||
b957e937 DJ |
418 | linux_supports_tracefork_flag = 0; |
419 | linux_supports_tracevforkdone_flag = 0; | |
420 | ||
421 | ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK); | |
422 | if (ret != 0) | |
423 | return; | |
424 | ||
3993f6b1 DJ |
425 | child_pid = fork (); |
426 | if (child_pid == -1) | |
e2e0b3e5 | 427 | perror_with_name (("fork")); |
3993f6b1 DJ |
428 | |
429 | if (child_pid == 0) | |
430 | linux_tracefork_child (); | |
431 | ||
b957e937 | 432 | ret = my_waitpid (child_pid, &status, 0); |
3993f6b1 | 433 | if (ret == -1) |
e2e0b3e5 | 434 | perror_with_name (("waitpid")); |
3993f6b1 | 435 | else if (ret != child_pid) |
8a3fe4f8 | 436 | error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret); |
3993f6b1 | 437 | if (! WIFSTOPPED (status)) |
8a3fe4f8 | 438 | error (_("linux_test_for_tracefork: waitpid: unexpected status %d."), status); |
3993f6b1 | 439 | |
3993f6b1 DJ |
440 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK); |
441 | if (ret != 0) | |
442 | { | |
b957e937 DJ |
443 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
444 | if (ret != 0) | |
445 | { | |
8a3fe4f8 | 446 | warning (_("linux_test_for_tracefork: failed to kill child")); |
b957e937 DJ |
447 | return; |
448 | } | |
449 | ||
450 | ret = my_waitpid (child_pid, &status, 0); | |
451 | if (ret != child_pid) | |
8a3fe4f8 | 452 | warning (_("linux_test_for_tracefork: failed to wait for killed child")); |
b957e937 | 453 | else if (!WIFSIGNALED (status)) |
8a3fe4f8 AC |
454 | warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from " |
455 | "killed child"), status); | |
b957e937 | 456 | |
3993f6b1 DJ |
457 | return; |
458 | } | |
459 | ||
9016a515 DJ |
460 | /* Check whether PTRACE_O_TRACEVFORKDONE is available. */ |
461 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, | |
462 | PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE); | |
463 | linux_supports_tracevforkdone_flag = (ret == 0); | |
464 | ||
b957e937 DJ |
465 | ret = ptrace (PTRACE_CONT, child_pid, 0, 0); |
466 | if (ret != 0) | |
8a3fe4f8 | 467 | warning (_("linux_test_for_tracefork: failed to resume child")); |
b957e937 DJ |
468 | |
469 | ret = my_waitpid (child_pid, &status, 0); | |
470 | ||
3993f6b1 DJ |
471 | if (ret == child_pid && WIFSTOPPED (status) |
472 | && status >> 16 == PTRACE_EVENT_FORK) | |
473 | { | |
474 | second_pid = 0; | |
475 | ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid); | |
476 | if (ret == 0 && second_pid != 0) | |
477 | { | |
478 | int second_status; | |
479 | ||
480 | linux_supports_tracefork_flag = 1; | |
b957e937 DJ |
481 | my_waitpid (second_pid, &second_status, 0); |
482 | ret = ptrace (PTRACE_KILL, second_pid, 0, 0); | |
483 | if (ret != 0) | |
8a3fe4f8 | 484 | warning (_("linux_test_for_tracefork: failed to kill second child")); |
97725dc4 | 485 | my_waitpid (second_pid, &status, 0); |
3993f6b1 DJ |
486 | } |
487 | } | |
b957e937 | 488 | else |
8a3fe4f8 AC |
489 | warning (_("linux_test_for_tracefork: unexpected result from waitpid " |
490 | "(%d, status 0x%x)"), ret, status); | |
3993f6b1 | 491 | |
b957e937 DJ |
492 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); |
493 | if (ret != 0) | |
8a3fe4f8 | 494 | warning (_("linux_test_for_tracefork: failed to kill child")); |
b957e937 | 495 | my_waitpid (child_pid, &status, 0); |
3993f6b1 DJ |
496 | } |
497 | ||
498 | /* Return non-zero iff we have tracefork functionality available. | |
499 | This function also sets linux_supports_tracefork_flag. */ | |
500 | ||
501 | static int | |
b957e937 | 502 | linux_supports_tracefork (int pid) |
3993f6b1 DJ |
503 | { |
504 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 505 | linux_test_for_tracefork (pid); |
3993f6b1 DJ |
506 | return linux_supports_tracefork_flag; |
507 | } | |
508 | ||
9016a515 | 509 | static int |
b957e937 | 510 | linux_supports_tracevforkdone (int pid) |
9016a515 DJ |
511 | { |
512 | if (linux_supports_tracefork_flag == -1) | |
b957e937 | 513 | linux_test_for_tracefork (pid); |
9016a515 DJ |
514 | return linux_supports_tracevforkdone_flag; |
515 | } | |
516 | ||
3993f6b1 | 517 | \f |
4de4c07c DJ |
518 | void |
519 | linux_enable_event_reporting (ptid_t ptid) | |
520 | { | |
d3587048 | 521 | int pid = ptid_get_lwp (ptid); |
4de4c07c DJ |
522 | int options; |
523 | ||
d3587048 DJ |
524 | if (pid == 0) |
525 | pid = ptid_get_pid (ptid); | |
526 | ||
b957e937 | 527 | if (! linux_supports_tracefork (pid)) |
4de4c07c DJ |
528 | return; |
529 | ||
a2f23071 DJ |
530 | options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC |
531 | | PTRACE_O_TRACECLONE; | |
b957e937 | 532 | if (linux_supports_tracevforkdone (pid)) |
9016a515 DJ |
533 | options |= PTRACE_O_TRACEVFORKDONE; |
534 | ||
535 | /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support | |
536 | read-only process state. */ | |
4de4c07c DJ |
537 | |
538 | ptrace (PTRACE_SETOPTIONS, pid, 0, options); | |
539 | } | |
540 | ||
6d8fd2b7 UW |
541 | static void |
542 | linux_child_post_attach (int pid) | |
4de4c07c DJ |
543 | { |
544 | linux_enable_event_reporting (pid_to_ptid (pid)); | |
0ec9a092 | 545 | check_for_thread_db (); |
4de4c07c DJ |
546 | } |
547 | ||
10d6c8cd | 548 | static void |
4de4c07c DJ |
549 | linux_child_post_startup_inferior (ptid_t ptid) |
550 | { | |
551 | linux_enable_event_reporting (ptid); | |
0ec9a092 | 552 | check_for_thread_db (); |
4de4c07c DJ |
553 | } |
554 | ||
6d8fd2b7 UW |
555 | static int |
556 | linux_child_follow_fork (struct target_ops *ops, int follow_child) | |
3993f6b1 | 557 | { |
4de4c07c DJ |
558 | ptid_t last_ptid; |
559 | struct target_waitstatus last_status; | |
9016a515 | 560 | int has_vforked; |
4de4c07c DJ |
561 | int parent_pid, child_pid; |
562 | ||
b84876c2 PA |
563 | if (target_can_async_p ()) |
564 | target_async (NULL, 0); | |
565 | ||
4de4c07c | 566 | get_last_target_status (&last_ptid, &last_status); |
9016a515 | 567 | has_vforked = (last_status.kind == TARGET_WAITKIND_VFORKED); |
d3587048 DJ |
568 | parent_pid = ptid_get_lwp (last_ptid); |
569 | if (parent_pid == 0) | |
570 | parent_pid = ptid_get_pid (last_ptid); | |
4de4c07c DJ |
571 | child_pid = last_status.value.related_pid; |
572 | ||
573 | if (! follow_child) | |
574 | { | |
575 | /* We're already attached to the parent, by default. */ | |
576 | ||
577 | /* Before detaching from the child, remove all breakpoints from | |
578 | it. (This won't actually modify the breakpoint list, but will | |
579 | physically remove the breakpoints from the child.) */ | |
9016a515 DJ |
580 | /* If we vforked this will remove the breakpoints from the parent |
581 | also, but they'll be reinserted below. */ | |
4de4c07c DJ |
582 | detach_breakpoints (child_pid); |
583 | ||
ac264b3b MS |
584 | /* Detach new forked process? */ |
585 | if (detach_fork) | |
f75c00e4 | 586 | { |
e85a822c | 587 | if (info_verbose || debug_linux_nat) |
ac264b3b MS |
588 | { |
589 | target_terminal_ours (); | |
590 | fprintf_filtered (gdb_stdlog, | |
591 | "Detaching after fork from child process %d.\n", | |
592 | child_pid); | |
593 | } | |
4de4c07c | 594 | |
ac264b3b MS |
595 | ptrace (PTRACE_DETACH, child_pid, 0, 0); |
596 | } | |
597 | else | |
598 | { | |
599 | struct fork_info *fp; | |
600 | /* Retain child fork in ptrace (stopped) state. */ | |
601 | fp = find_fork_pid (child_pid); | |
602 | if (!fp) | |
603 | fp = add_fork (child_pid); | |
604 | fork_save_infrun_state (fp, 0); | |
605 | } | |
9016a515 DJ |
606 | |
607 | if (has_vforked) | |
608 | { | |
b957e937 DJ |
609 | gdb_assert (linux_supports_tracefork_flag >= 0); |
610 | if (linux_supports_tracevforkdone (0)) | |
9016a515 DJ |
611 | { |
612 | int status; | |
613 | ||
614 | ptrace (PTRACE_CONT, parent_pid, 0, 0); | |
58aecb61 | 615 | my_waitpid (parent_pid, &status, __WALL); |
c874c7fc | 616 | if ((status >> 16) != PTRACE_EVENT_VFORK_DONE) |
8a3fe4f8 AC |
617 | warning (_("Unexpected waitpid result %06x when waiting for " |
618 | "vfork-done"), status); | |
9016a515 DJ |
619 | } |
620 | else | |
621 | { | |
622 | /* We can't insert breakpoints until the child has | |
623 | finished with the shared memory region. We need to | |
624 | wait until that happens. Ideal would be to just | |
625 | call: | |
626 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
627 | - waitpid (parent_pid, &status, __WALL); | |
628 | However, most architectures can't handle a syscall | |
629 | being traced on the way out if it wasn't traced on | |
630 | the way in. | |
631 | ||
632 | We might also think to loop, continuing the child | |
633 | until it exits or gets a SIGTRAP. One problem is | |
634 | that the child might call ptrace with PTRACE_TRACEME. | |
635 | ||
636 | There's no simple and reliable way to figure out when | |
637 | the vforked child will be done with its copy of the | |
638 | shared memory. We could step it out of the syscall, | |
639 | two instructions, let it go, and then single-step the | |
640 | parent once. When we have hardware single-step, this | |
641 | would work; with software single-step it could still | |
642 | be made to work but we'd have to be able to insert | |
643 | single-step breakpoints in the child, and we'd have | |
644 | to insert -just- the single-step breakpoint in the | |
645 | parent. Very awkward. | |
646 | ||
647 | In the end, the best we can do is to make sure it | |
648 | runs for a little while. Hopefully it will be out of | |
649 | range of any breakpoints we reinsert. Usually this | |
650 | is only the single-step breakpoint at vfork's return | |
651 | point. */ | |
652 | ||
653 | usleep (10000); | |
654 | } | |
655 | ||
656 | /* Since we vforked, breakpoints were removed in the parent | |
657 | too. Put them back. */ | |
658 | reattach_breakpoints (parent_pid); | |
659 | } | |
4de4c07c | 660 | } |
3993f6b1 | 661 | else |
4de4c07c DJ |
662 | { |
663 | char child_pid_spelling[40]; | |
664 | ||
665 | /* Needed to keep the breakpoint lists in sync. */ | |
9016a515 DJ |
666 | if (! has_vforked) |
667 | detach_breakpoints (child_pid); | |
4de4c07c DJ |
668 | |
669 | /* Before detaching from the parent, remove all breakpoints from it. */ | |
670 | remove_breakpoints (); | |
671 | ||
e85a822c | 672 | if (info_verbose || debug_linux_nat) |
f75c00e4 DJ |
673 | { |
674 | target_terminal_ours (); | |
ac264b3b MS |
675 | fprintf_filtered (gdb_stdlog, |
676 | "Attaching after fork to child process %d.\n", | |
677 | child_pid); | |
f75c00e4 | 678 | } |
4de4c07c | 679 | |
9016a515 DJ |
680 | /* If we're vforking, we may want to hold on to the parent until |
681 | the child exits or execs. At exec time we can remove the old | |
682 | breakpoints from the parent and detach it; at exit time we | |
683 | could do the same (or even, sneakily, resume debugging it - the | |
684 | child's exec has failed, or something similar). | |
685 | ||
686 | This doesn't clean up "properly", because we can't call | |
687 | target_detach, but that's OK; if the current target is "child", | |
688 | then it doesn't need any further cleanups, and lin_lwp will | |
689 | generally not encounter vfork (vfork is defined to fork | |
690 | in libpthread.so). | |
691 | ||
692 | The holding part is very easy if we have VFORKDONE events; | |
693 | but keeping track of both processes is beyond GDB at the | |
694 | moment. So we don't expose the parent to the rest of GDB. | |
695 | Instead we quietly hold onto it until such time as we can | |
696 | safely resume it. */ | |
697 | ||
698 | if (has_vforked) | |
699 | linux_parent_pid = parent_pid; | |
ac264b3b MS |
700 | else if (!detach_fork) |
701 | { | |
702 | struct fork_info *fp; | |
703 | /* Retain parent fork in ptrace (stopped) state. */ | |
704 | fp = find_fork_pid (parent_pid); | |
705 | if (!fp) | |
706 | fp = add_fork (parent_pid); | |
707 | fork_save_infrun_state (fp, 0); | |
708 | } | |
9016a515 | 709 | else |
b84876c2 | 710 | target_detach (NULL, 0); |
4de4c07c | 711 | |
9f0bdab8 | 712 | inferior_ptid = ptid_build (child_pid, child_pid, 0); |
ee057212 DJ |
713 | |
714 | /* Reinstall ourselves, since we might have been removed in | |
715 | target_detach (which does other necessary cleanup). */ | |
ac264b3b | 716 | |
ee057212 | 717 | push_target (ops); |
9f0bdab8 | 718 | linux_nat_switch_fork (inferior_ptid); |
ef29ce1a | 719 | check_for_thread_db (); |
4de4c07c DJ |
720 | |
721 | /* Reset breakpoints in the child as appropriate. */ | |
722 | follow_inferior_reset_breakpoints (); | |
723 | } | |
724 | ||
b84876c2 PA |
725 | if (target_can_async_p ()) |
726 | target_async (inferior_event_handler, 0); | |
727 | ||
4de4c07c DJ |
728 | return 0; |
729 | } | |
730 | ||
4de4c07c | 731 | \f |
6d8fd2b7 UW |
732 | static void |
733 | linux_child_insert_fork_catchpoint (int pid) | |
4de4c07c | 734 | { |
b957e937 | 735 | if (! linux_supports_tracefork (pid)) |
8a3fe4f8 | 736 | error (_("Your system does not support fork catchpoints.")); |
3993f6b1 DJ |
737 | } |
738 | ||
6d8fd2b7 UW |
739 | static void |
740 | linux_child_insert_vfork_catchpoint (int pid) | |
3993f6b1 | 741 | { |
b957e937 | 742 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 743 | error (_("Your system does not support vfork catchpoints.")); |
3993f6b1 DJ |
744 | } |
745 | ||
6d8fd2b7 UW |
746 | static void |
747 | linux_child_insert_exec_catchpoint (int pid) | |
3993f6b1 | 748 | { |
b957e937 | 749 | if (!linux_supports_tracefork (pid)) |
8a3fe4f8 | 750 | error (_("Your system does not support exec catchpoints.")); |
3993f6b1 DJ |
751 | } |
752 | ||
d6b0e80f AC |
753 | /* On GNU/Linux there are no real LWP's. The closest thing to LWP's |
754 | are processes sharing the same VM space. A multi-threaded process | |
755 | is basically a group of such processes. However, such a grouping | |
756 | is almost entirely a user-space issue; the kernel doesn't enforce | |
757 | such a grouping at all (this might change in the future). In | |
758 | general, we'll rely on the threads library (i.e. the GNU/Linux | |
759 | Threads library) to provide such a grouping. | |
760 | ||
761 | It is perfectly well possible to write a multi-threaded application | |
762 | without the assistance of a threads library, by using the clone | |
763 | system call directly. This module should be able to give some | |
764 | rudimentary support for debugging such applications if developers | |
765 | specify the CLONE_PTRACE flag in the clone system call, and are | |
766 | using the Linux kernel 2.4 or above. | |
767 | ||
768 | Note that there are some peculiarities in GNU/Linux that affect | |
769 | this code: | |
770 | ||
771 | - In general one should specify the __WCLONE flag to waitpid in | |
772 | order to make it report events for any of the cloned processes | |
773 | (and leave it out for the initial process). However, if a cloned | |
774 | process has exited the exit status is only reported if the | |
775 | __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but | |
776 | we cannot use it since GDB must work on older systems too. | |
777 | ||
778 | - When a traced, cloned process exits and is waited for by the | |
779 | debugger, the kernel reassigns it to the original parent and | |
780 | keeps it around as a "zombie". Somehow, the GNU/Linux Threads | |
781 | library doesn't notice this, which leads to the "zombie problem": | |
782 | When debugged a multi-threaded process that spawns a lot of | |
783 | threads will run out of processes, even if the threads exit, | |
784 | because the "zombies" stay around. */ | |
785 | ||
786 | /* List of known LWPs. */ | |
9f0bdab8 | 787 | struct lwp_info *lwp_list; |
d6b0e80f AC |
788 | |
789 | /* Number of LWPs in the list. */ | |
790 | static int num_lwps; | |
d6b0e80f AC |
791 | \f |
792 | ||
d6b0e80f AC |
793 | /* Since we cannot wait (in linux_nat_wait) for the initial process and |
794 | any cloned processes with a single call to waitpid, we have to use | |
795 | the WNOHANG flag and call waitpid in a loop. To optimize | |
796 | things a bit we use `sigsuspend' to wake us up when a process has | |
797 | something to report (it will send us a SIGCHLD if it has). To make | |
798 | this work we have to juggle with the signal mask. We save the | |
799 | original signal mask such that we can restore it before creating a | |
800 | new process in order to avoid blocking certain signals in the | |
801 | inferior. We then block SIGCHLD during the waitpid/sigsuspend | |
802 | loop. */ | |
803 | ||
804 | /* Original signal mask. */ | |
805 | static sigset_t normal_mask; | |
806 | ||
807 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in | |
808 | _initialize_linux_nat. */ | |
809 | static sigset_t suspend_mask; | |
810 | ||
b84876c2 PA |
811 | /* SIGCHLD action for synchronous mode. */ |
812 | struct sigaction sync_sigchld_action; | |
813 | ||
814 | /* SIGCHLD action for asynchronous mode. */ | |
815 | static struct sigaction async_sigchld_action; | |
d6b0e80f AC |
816 | \f |
817 | ||
818 | /* Prototypes for local functions. */ | |
819 | static int stop_wait_callback (struct lwp_info *lp, void *data); | |
820 | static int linux_nat_thread_alive (ptid_t ptid); | |
6d8fd2b7 | 821 | static char *linux_child_pid_to_exec_file (int pid); |
710151dd PA |
822 | static int cancel_breakpoint (struct lwp_info *lp); |
823 | ||
d6b0e80f AC |
824 | \f |
825 | /* Convert wait status STATUS to a string. Used for printing debug | |
826 | messages only. */ | |
827 | ||
828 | static char * | |
829 | status_to_str (int status) | |
830 | { | |
831 | static char buf[64]; | |
832 | ||
833 | if (WIFSTOPPED (status)) | |
834 | snprintf (buf, sizeof (buf), "%s (stopped)", | |
835 | strsignal (WSTOPSIG (status))); | |
836 | else if (WIFSIGNALED (status)) | |
837 | snprintf (buf, sizeof (buf), "%s (terminated)", | |
838 | strsignal (WSTOPSIG (status))); | |
839 | else | |
840 | snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status)); | |
841 | ||
842 | return buf; | |
843 | } | |
844 | ||
845 | /* Initialize the list of LWPs. Note that this module, contrary to | |
846 | what GDB's generic threads layer does for its thread list, | |
847 | re-initializes the LWP lists whenever we mourn or detach (which | |
848 | doesn't involve mourning) the inferior. */ | |
849 | ||
850 | static void | |
851 | init_lwp_list (void) | |
852 | { | |
853 | struct lwp_info *lp, *lpnext; | |
854 | ||
855 | for (lp = lwp_list; lp; lp = lpnext) | |
856 | { | |
857 | lpnext = lp->next; | |
858 | xfree (lp); | |
859 | } | |
860 | ||
861 | lwp_list = NULL; | |
862 | num_lwps = 0; | |
d6b0e80f AC |
863 | } |
864 | ||
f973ed9c | 865 | /* Add the LWP specified by PID to the list. Return a pointer to the |
9f0bdab8 DJ |
866 | structure describing the new LWP. The LWP should already be stopped |
867 | (with an exception for the very first LWP). */ | |
d6b0e80f AC |
868 | |
869 | static struct lwp_info * | |
870 | add_lwp (ptid_t ptid) | |
871 | { | |
872 | struct lwp_info *lp; | |
873 | ||
874 | gdb_assert (is_lwp (ptid)); | |
875 | ||
876 | lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info)); | |
877 | ||
878 | memset (lp, 0, sizeof (struct lwp_info)); | |
879 | ||
880 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
881 | ||
882 | lp->ptid = ptid; | |
883 | ||
884 | lp->next = lwp_list; | |
885 | lwp_list = lp; | |
f973ed9c | 886 | ++num_lwps; |
d6b0e80f | 887 | |
9f0bdab8 DJ |
888 | if (num_lwps > 1 && linux_nat_new_thread != NULL) |
889 | linux_nat_new_thread (ptid); | |
890 | ||
d6b0e80f AC |
891 | return lp; |
892 | } | |
893 | ||
894 | /* Remove the LWP specified by PID from the list. */ | |
895 | ||
896 | static void | |
897 | delete_lwp (ptid_t ptid) | |
898 | { | |
899 | struct lwp_info *lp, *lpprev; | |
900 | ||
901 | lpprev = NULL; | |
902 | ||
903 | for (lp = lwp_list; lp; lpprev = lp, lp = lp->next) | |
904 | if (ptid_equal (lp->ptid, ptid)) | |
905 | break; | |
906 | ||
907 | if (!lp) | |
908 | return; | |
909 | ||
d6b0e80f AC |
910 | num_lwps--; |
911 | ||
912 | if (lpprev) | |
913 | lpprev->next = lp->next; | |
914 | else | |
915 | lwp_list = lp->next; | |
916 | ||
917 | xfree (lp); | |
918 | } | |
919 | ||
920 | /* Return a pointer to the structure describing the LWP corresponding | |
921 | to PID. If no corresponding LWP could be found, return NULL. */ | |
922 | ||
923 | static struct lwp_info * | |
924 | find_lwp_pid (ptid_t ptid) | |
925 | { | |
926 | struct lwp_info *lp; | |
927 | int lwp; | |
928 | ||
929 | if (is_lwp (ptid)) | |
930 | lwp = GET_LWP (ptid); | |
931 | else | |
932 | lwp = GET_PID (ptid); | |
933 | ||
934 | for (lp = lwp_list; lp; lp = lp->next) | |
935 | if (lwp == GET_LWP (lp->ptid)) | |
936 | return lp; | |
937 | ||
938 | return NULL; | |
939 | } | |
940 | ||
941 | /* Call CALLBACK with its second argument set to DATA for every LWP in | |
942 | the list. If CALLBACK returns 1 for a particular LWP, return a | |
943 | pointer to the structure describing that LWP immediately. | |
944 | Otherwise return NULL. */ | |
945 | ||
946 | struct lwp_info * | |
947 | iterate_over_lwps (int (*callback) (struct lwp_info *, void *), void *data) | |
948 | { | |
949 | struct lwp_info *lp, *lpnext; | |
950 | ||
951 | for (lp = lwp_list; lp; lp = lpnext) | |
952 | { | |
953 | lpnext = lp->next; | |
954 | if ((*callback) (lp, data)) | |
955 | return lp; | |
956 | } | |
957 | ||
958 | return NULL; | |
959 | } | |
960 | ||
f973ed9c DJ |
961 | /* Update our internal state when changing from one fork (checkpoint, |
962 | et cetera) to another indicated by NEW_PTID. We can only switch | |
963 | single-threaded applications, so we only create one new LWP, and | |
964 | the previous list is discarded. */ | |
965 | ||
966 | void | |
967 | linux_nat_switch_fork (ptid_t new_ptid) | |
968 | { | |
969 | struct lwp_info *lp; | |
970 | ||
728c8f58 | 971 | init_thread_list (); |
f973ed9c DJ |
972 | init_lwp_list (); |
973 | lp = add_lwp (new_ptid); | |
728c8f58 | 974 | add_thread_silent (new_ptid); |
f973ed9c DJ |
975 | lp->stopped = 1; |
976 | } | |
977 | ||
e26af52f DJ |
978 | /* Record a PTID for later deletion. */ |
979 | ||
980 | struct saved_ptids | |
981 | { | |
982 | ptid_t ptid; | |
983 | struct saved_ptids *next; | |
984 | }; | |
985 | static struct saved_ptids *threads_to_delete; | |
986 | ||
987 | static void | |
988 | record_dead_thread (ptid_t ptid) | |
989 | { | |
990 | struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids)); | |
991 | p->ptid = ptid; | |
992 | p->next = threads_to_delete; | |
993 | threads_to_delete = p; | |
994 | } | |
995 | ||
996 | /* Delete any dead threads which are not the current thread. */ | |
997 | ||
998 | static void | |
999 | prune_lwps (void) | |
1000 | { | |
1001 | struct saved_ptids **p = &threads_to_delete; | |
1002 | ||
1003 | while (*p) | |
1004 | if (! ptid_equal ((*p)->ptid, inferior_ptid)) | |
1005 | { | |
1006 | struct saved_ptids *tmp = *p; | |
1007 | delete_thread (tmp->ptid); | |
1008 | *p = tmp->next; | |
1009 | xfree (tmp); | |
1010 | } | |
1011 | else | |
1012 | p = &(*p)->next; | |
1013 | } | |
1014 | ||
e26af52f DJ |
1015 | /* Handle the exit of a single thread LP. */ |
1016 | ||
1017 | static void | |
1018 | exit_lwp (struct lwp_info *lp) | |
1019 | { | |
063bfe2e VP |
1020 | struct thread_info *th = find_thread_pid (lp->ptid); |
1021 | ||
1022 | if (th) | |
e26af52f | 1023 | { |
17faa917 DJ |
1024 | if (print_thread_events) |
1025 | printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid)); | |
1026 | ||
e26af52f DJ |
1027 | /* Core GDB cannot deal with us deleting the current thread. */ |
1028 | if (!ptid_equal (lp->ptid, inferior_ptid)) | |
1029 | delete_thread (lp->ptid); | |
1030 | else | |
1031 | record_dead_thread (lp->ptid); | |
e26af52f DJ |
1032 | } |
1033 | ||
1034 | delete_lwp (lp->ptid); | |
1035 | } | |
1036 | ||
a0ef4274 DJ |
1037 | /* Detect `T (stopped)' in `/proc/PID/status'. |
1038 | Other states including `T (tracing stop)' are reported as false. */ | |
1039 | ||
1040 | static int | |
1041 | pid_is_stopped (pid_t pid) | |
1042 | { | |
1043 | FILE *status_file; | |
1044 | char buf[100]; | |
1045 | int retval = 0; | |
1046 | ||
1047 | snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid); | |
1048 | status_file = fopen (buf, "r"); | |
1049 | if (status_file != NULL) | |
1050 | { | |
1051 | int have_state = 0; | |
1052 | ||
1053 | while (fgets (buf, sizeof (buf), status_file)) | |
1054 | { | |
1055 | if (strncmp (buf, "State:", 6) == 0) | |
1056 | { | |
1057 | have_state = 1; | |
1058 | break; | |
1059 | } | |
1060 | } | |
1061 | if (have_state && strstr (buf, "T (stopped)") != NULL) | |
1062 | retval = 1; | |
1063 | fclose (status_file); | |
1064 | } | |
1065 | return retval; | |
1066 | } | |
1067 | ||
1068 | /* Wait for the LWP specified by LP, which we have just attached to. | |
1069 | Returns a wait status for that LWP, to cache. */ | |
1070 | ||
1071 | static int | |
1072 | linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned, | |
1073 | int *signalled) | |
1074 | { | |
1075 | pid_t new_pid, pid = GET_LWP (ptid); | |
1076 | int status; | |
1077 | ||
1078 | if (pid_is_stopped (pid)) | |
1079 | { | |
1080 | if (debug_linux_nat) | |
1081 | fprintf_unfiltered (gdb_stdlog, | |
1082 | "LNPAW: Attaching to a stopped process\n"); | |
1083 | ||
1084 | /* The process is definitely stopped. It is in a job control | |
1085 | stop, unless the kernel predates the TASK_STOPPED / | |
1086 | TASK_TRACED distinction, in which case it might be in a | |
1087 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1088 | can kill it, signal it, et cetera. | |
1089 | ||
1090 | First make sure there is a pending SIGSTOP. Since we are | |
1091 | already attached, the process can not transition from stopped | |
1092 | to running without a PTRACE_CONT; so we know this signal will | |
1093 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1094 | probably already in the queue (unless this kernel is old | |
1095 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1096 | is not an RT signal, it can only be queued once. */ | |
1097 | kill_lwp (pid, SIGSTOP); | |
1098 | ||
1099 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1100 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1101 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1102 | } | |
1103 | ||
1104 | /* Make sure the initial process is stopped. The user-level threads | |
1105 | layer might want to poke around in the inferior, and that won't | |
1106 | work if things haven't stabilized yet. */ | |
1107 | new_pid = my_waitpid (pid, &status, 0); | |
1108 | if (new_pid == -1 && errno == ECHILD) | |
1109 | { | |
1110 | if (first) | |
1111 | warning (_("%s is a cloned process"), target_pid_to_str (ptid)); | |
1112 | ||
1113 | /* Try again with __WCLONE to check cloned processes. */ | |
1114 | new_pid = my_waitpid (pid, &status, __WCLONE); | |
1115 | *cloned = 1; | |
1116 | } | |
1117 | ||
1118 | gdb_assert (pid == new_pid && WIFSTOPPED (status)); | |
1119 | ||
1120 | if (WSTOPSIG (status) != SIGSTOP) | |
1121 | { | |
1122 | *signalled = 1; | |
1123 | if (debug_linux_nat) | |
1124 | fprintf_unfiltered (gdb_stdlog, | |
1125 | "LNPAW: Received %s after attaching\n", | |
1126 | status_to_str (status)); | |
1127 | } | |
1128 | ||
1129 | return status; | |
1130 | } | |
1131 | ||
1132 | /* Attach to the LWP specified by PID. Return 0 if successful or -1 | |
1133 | if the new LWP could not be attached. */ | |
d6b0e80f | 1134 | |
9ee57c33 | 1135 | int |
93815fbf | 1136 | lin_lwp_attach_lwp (ptid_t ptid) |
d6b0e80f | 1137 | { |
9ee57c33 | 1138 | struct lwp_info *lp; |
b84876c2 | 1139 | int async_events_were_enabled = 0; |
d6b0e80f AC |
1140 | |
1141 | gdb_assert (is_lwp (ptid)); | |
1142 | ||
b84876c2 PA |
1143 | if (target_can_async_p ()) |
1144 | async_events_were_enabled = linux_nat_async_events (0); | |
d6b0e80f | 1145 | |
9ee57c33 | 1146 | lp = find_lwp_pid (ptid); |
d6b0e80f AC |
1147 | |
1148 | /* We assume that we're already attached to any LWP that has an id | |
1149 | equal to the overall process id, and to any LWP that is already | |
1150 | in our list of LWPs. If we're not seeing exit events from threads | |
1151 | and we've had PID wraparound since we last tried to stop all threads, | |
1152 | this assumption might be wrong; fortunately, this is very unlikely | |
1153 | to happen. */ | |
9ee57c33 | 1154 | if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL) |
d6b0e80f | 1155 | { |
a0ef4274 | 1156 | int status, cloned = 0, signalled = 0; |
d6b0e80f AC |
1157 | |
1158 | if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0) | |
9ee57c33 DJ |
1159 | { |
1160 | /* If we fail to attach to the thread, issue a warning, | |
1161 | but continue. One way this can happen is if thread | |
e9efe249 | 1162 | creation is interrupted; as of Linux kernel 2.6.19, a |
9ee57c33 DJ |
1163 | bug may place threads in the thread list and then fail |
1164 | to create them. */ | |
1165 | warning (_("Can't attach %s: %s"), target_pid_to_str (ptid), | |
1166 | safe_strerror (errno)); | |
1167 | return -1; | |
1168 | } | |
1169 | ||
d6b0e80f AC |
1170 | if (debug_linux_nat) |
1171 | fprintf_unfiltered (gdb_stdlog, | |
1172 | "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
1173 | target_pid_to_str (ptid)); | |
1174 | ||
a0ef4274 DJ |
1175 | status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled); |
1176 | lp = add_lwp (ptid); | |
1177 | lp->stopped = 1; | |
1178 | lp->cloned = cloned; | |
1179 | lp->signalled = signalled; | |
1180 | if (WSTOPSIG (status) != SIGSTOP) | |
d6b0e80f | 1181 | { |
a0ef4274 DJ |
1182 | lp->resumed = 1; |
1183 | lp->status = status; | |
d6b0e80f AC |
1184 | } |
1185 | ||
a0ef4274 | 1186 | target_post_attach (GET_LWP (lp->ptid)); |
d6b0e80f AC |
1187 | |
1188 | if (debug_linux_nat) | |
1189 | { | |
1190 | fprintf_unfiltered (gdb_stdlog, | |
1191 | "LLAL: waitpid %s received %s\n", | |
1192 | target_pid_to_str (ptid), | |
1193 | status_to_str (status)); | |
1194 | } | |
1195 | } | |
1196 | else | |
1197 | { | |
1198 | /* We assume that the LWP representing the original process is | |
1199 | already stopped. Mark it as stopped in the data structure | |
155bd5d1 AC |
1200 | that the GNU/linux ptrace layer uses to keep track of |
1201 | threads. Note that this won't have already been done since | |
1202 | the main thread will have, we assume, been stopped by an | |
1203 | attach from a different layer. */ | |
9ee57c33 DJ |
1204 | if (lp == NULL) |
1205 | lp = add_lwp (ptid); | |
d6b0e80f AC |
1206 | lp->stopped = 1; |
1207 | } | |
9ee57c33 | 1208 | |
b84876c2 PA |
1209 | if (async_events_were_enabled) |
1210 | linux_nat_async_events (1); | |
1211 | ||
9ee57c33 | 1212 | return 0; |
d6b0e80f AC |
1213 | } |
1214 | ||
b84876c2 PA |
1215 | static void |
1216 | linux_nat_create_inferior (char *exec_file, char *allargs, char **env, | |
1217 | int from_tty) | |
1218 | { | |
1219 | int saved_async = 0; | |
1220 | ||
1221 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1222 | we have to mask the async mode. */ | |
1223 | ||
1224 | if (target_can_async_p ()) | |
1225 | saved_async = linux_nat_async_mask (0); | |
1226 | else | |
1227 | { | |
1228 | /* Restore the original signal mask. */ | |
1229 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1230 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1231 | suspend_mask = normal_mask; | |
1232 | sigdelset (&suspend_mask, SIGCHLD); | |
1233 | } | |
1234 | ||
1235 | linux_ops->to_create_inferior (exec_file, allargs, env, from_tty); | |
1236 | ||
1237 | if (saved_async) | |
1238 | linux_nat_async_mask (saved_async); | |
1239 | } | |
1240 | ||
d6b0e80f AC |
1241 | static void |
1242 | linux_nat_attach (char *args, int from_tty) | |
1243 | { | |
1244 | struct lwp_info *lp; | |
d6b0e80f AC |
1245 | int status; |
1246 | ||
1247 | /* FIXME: We should probably accept a list of process id's, and | |
1248 | attach all of them. */ | |
10d6c8cd | 1249 | linux_ops->to_attach (args, from_tty); |
d6b0e80f | 1250 | |
b84876c2 PA |
1251 | if (!target_can_async_p ()) |
1252 | { | |
1253 | /* Restore the original signal mask. */ | |
1254 | sigprocmask (SIG_SETMASK, &normal_mask, NULL); | |
1255 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
1256 | suspend_mask = normal_mask; | |
1257 | sigdelset (&suspend_mask, SIGCHLD); | |
1258 | } | |
1259 | ||
9f0bdab8 DJ |
1260 | /* Add the initial process as the first LWP to the list. */ |
1261 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid)); | |
1262 | lp = add_lwp (inferior_ptid); | |
a0ef4274 DJ |
1263 | |
1264 | status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned, | |
1265 | &lp->signalled); | |
1266 | lp->stopped = 1; | |
9f0bdab8 | 1267 | |
403fe197 PA |
1268 | /* If this process is not using thread_db, then we still don't |
1269 | detect any other threads, but add at least this one. */ | |
1270 | add_thread_silent (lp->ptid); | |
1271 | ||
a0ef4274 | 1272 | /* Save the wait status to report later. */ |
d6b0e80f | 1273 | lp->resumed = 1; |
a0ef4274 DJ |
1274 | if (debug_linux_nat) |
1275 | fprintf_unfiltered (gdb_stdlog, | |
1276 | "LNA: waitpid %ld, saving status %s\n", | |
1277 | (long) GET_PID (lp->ptid), status_to_str (status)); | |
710151dd PA |
1278 | |
1279 | if (!target_can_async_p ()) | |
a0ef4274 | 1280 | lp->status = status; |
710151dd PA |
1281 | else |
1282 | { | |
1283 | /* We already waited for this LWP, so put the wait result on the | |
1284 | pipe. The event loop will wake up and gets us to handling | |
1285 | this event. */ | |
a0ef4274 DJ |
1286 | linux_nat_event_pipe_push (GET_PID (lp->ptid), status, |
1287 | lp->cloned ? __WCLONE : 0); | |
b84876c2 PA |
1288 | /* Register in the event loop. */ |
1289 | target_async (inferior_event_handler, 0); | |
d6b0e80f AC |
1290 | } |
1291 | } | |
1292 | ||
a0ef4274 DJ |
1293 | /* Get pending status of LP. */ |
1294 | static int | |
1295 | get_pending_status (struct lwp_info *lp, int *status) | |
1296 | { | |
1297 | struct target_waitstatus last; | |
1298 | ptid_t last_ptid; | |
1299 | ||
1300 | get_last_target_status (&last_ptid, &last); | |
1301 | ||
1302 | /* If this lwp is the ptid that GDB is processing an event from, the | |
1303 | signal will be in stop_signal. Otherwise, in all-stop + sync | |
1304 | mode, we may cache pending events in lp->status while trying to | |
1305 | stop all threads (see stop_wait_callback). In async mode, the | |
1306 | events are always cached in waitpid_queue. */ | |
1307 | ||
1308 | *status = 0; | |
1309 | if (GET_LWP (lp->ptid) == GET_LWP (last_ptid)) | |
1310 | { | |
1311 | if (stop_signal != TARGET_SIGNAL_0 | |
1312 | && signal_pass_state (stop_signal)) | |
1313 | *status = W_STOPCODE (target_signal_to_host (stop_signal)); | |
1314 | } | |
1315 | else if (target_can_async_p ()) | |
1316 | queued_waitpid (GET_LWP (lp->ptid), status, __WALL); | |
1317 | else | |
1318 | *status = lp->status; | |
1319 | ||
1320 | return 0; | |
1321 | } | |
1322 | ||
d6b0e80f AC |
1323 | static int |
1324 | detach_callback (struct lwp_info *lp, void *data) | |
1325 | { | |
1326 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); | |
1327 | ||
1328 | if (debug_linux_nat && lp->status) | |
1329 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1330 | strsignal (WSTOPSIG (lp->status)), | |
1331 | target_pid_to_str (lp->ptid)); | |
1332 | ||
a0ef4274 DJ |
1333 | /* If there is a pending SIGSTOP, get rid of it. */ |
1334 | if (lp->signalled) | |
d6b0e80f | 1335 | { |
d6b0e80f AC |
1336 | if (debug_linux_nat) |
1337 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 DJ |
1338 | "DC: Sending SIGCONT to %s\n", |
1339 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 1340 | |
a0ef4274 | 1341 | kill_lwp (GET_LWP (lp->ptid), SIGCONT); |
d6b0e80f | 1342 | lp->signalled = 0; |
d6b0e80f AC |
1343 | } |
1344 | ||
1345 | /* We don't actually detach from the LWP that has an id equal to the | |
1346 | overall process id just yet. */ | |
1347 | if (GET_LWP (lp->ptid) != GET_PID (lp->ptid)) | |
1348 | { | |
a0ef4274 DJ |
1349 | int status = 0; |
1350 | ||
1351 | /* Pass on any pending signal for this LWP. */ | |
1352 | get_pending_status (lp, &status); | |
1353 | ||
d6b0e80f AC |
1354 | errno = 0; |
1355 | if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0, | |
a0ef4274 | 1356 | WSTOPSIG (status)) < 0) |
8a3fe4f8 | 1357 | error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid), |
d6b0e80f AC |
1358 | safe_strerror (errno)); |
1359 | ||
1360 | if (debug_linux_nat) | |
1361 | fprintf_unfiltered (gdb_stdlog, | |
1362 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1363 | target_pid_to_str (lp->ptid), | |
1364 | strsignal (WSTOPSIG (lp->status))); | |
1365 | ||
1366 | delete_lwp (lp->ptid); | |
1367 | } | |
1368 | ||
1369 | return 0; | |
1370 | } | |
1371 | ||
1372 | static void | |
1373 | linux_nat_detach (char *args, int from_tty) | |
1374 | { | |
b84876c2 | 1375 | int pid; |
a0ef4274 DJ |
1376 | int status; |
1377 | enum target_signal sig; | |
1378 | ||
b84876c2 PA |
1379 | if (target_can_async_p ()) |
1380 | linux_nat_async (NULL, 0); | |
1381 | ||
d6b0e80f AC |
1382 | iterate_over_lwps (detach_callback, NULL); |
1383 | ||
1384 | /* Only the initial process should be left right now. */ | |
1385 | gdb_assert (num_lwps == 1); | |
1386 | ||
a0ef4274 DJ |
1387 | /* Pass on any pending signal for the last LWP. */ |
1388 | if ((args == NULL || *args == '\0') | |
1389 | && get_pending_status (lwp_list, &status) != -1 | |
1390 | && WIFSTOPPED (status)) | |
1391 | { | |
1392 | /* Put the signal number in ARGS so that inf_ptrace_detach will | |
1393 | pass it along with PTRACE_DETACH. */ | |
1394 | args = alloca (8); | |
1395 | sprintf (args, "%d", (int) WSTOPSIG (status)); | |
1396 | fprintf_unfiltered (gdb_stdlog, | |
1397 | "LND: Sending signal %s to %s\n", | |
1398 | args, | |
1399 | target_pid_to_str (lwp_list->ptid)); | |
1400 | } | |
1401 | ||
d6b0e80f AC |
1402 | /* Destroy LWP info; it's no longer valid. */ |
1403 | init_lwp_list (); | |
1404 | ||
b84876c2 PA |
1405 | pid = GET_PID (inferior_ptid); |
1406 | inferior_ptid = pid_to_ptid (pid); | |
10d6c8cd | 1407 | linux_ops->to_detach (args, from_tty); |
b84876c2 PA |
1408 | |
1409 | if (target_can_async_p ()) | |
1410 | drain_queued_events (pid); | |
d6b0e80f AC |
1411 | } |
1412 | ||
1413 | /* Resume LP. */ | |
1414 | ||
1415 | static int | |
1416 | resume_callback (struct lwp_info *lp, void *data) | |
1417 | { | |
1418 | if (lp->stopped && lp->status == 0) | |
1419 | { | |
10d6c8cd DJ |
1420 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
1421 | 0, TARGET_SIGNAL_0); | |
d6b0e80f AC |
1422 | if (debug_linux_nat) |
1423 | fprintf_unfiltered (gdb_stdlog, | |
1424 | "RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n", | |
1425 | target_pid_to_str (lp->ptid)); | |
1426 | lp->stopped = 0; | |
1427 | lp->step = 0; | |
9f0bdab8 | 1428 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
d6b0e80f AC |
1429 | } |
1430 | ||
1431 | return 0; | |
1432 | } | |
1433 | ||
1434 | static int | |
1435 | resume_clear_callback (struct lwp_info *lp, void *data) | |
1436 | { | |
1437 | lp->resumed = 0; | |
1438 | return 0; | |
1439 | } | |
1440 | ||
1441 | static int | |
1442 | resume_set_callback (struct lwp_info *lp, void *data) | |
1443 | { | |
1444 | lp->resumed = 1; | |
1445 | return 0; | |
1446 | } | |
1447 | ||
1448 | static void | |
1449 | linux_nat_resume (ptid_t ptid, int step, enum target_signal signo) | |
1450 | { | |
1451 | struct lwp_info *lp; | |
1452 | int resume_all; | |
1453 | ||
76f50ad1 DJ |
1454 | if (debug_linux_nat) |
1455 | fprintf_unfiltered (gdb_stdlog, | |
1456 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1457 | step ? "step" : "resume", | |
1458 | target_pid_to_str (ptid), | |
1459 | signo ? strsignal (signo) : "0", | |
1460 | target_pid_to_str (inferior_ptid)); | |
1461 | ||
e26af52f DJ |
1462 | prune_lwps (); |
1463 | ||
b84876c2 PA |
1464 | if (target_can_async_p ()) |
1465 | /* Block events while we're here. */ | |
1466 | linux_nat_async_events (0); | |
1467 | ||
d6b0e80f AC |
1468 | /* A specific PTID means `step only this process id'. */ |
1469 | resume_all = (PIDGET (ptid) == -1); | |
1470 | ||
1471 | if (resume_all) | |
1472 | iterate_over_lwps (resume_set_callback, NULL); | |
1473 | else | |
1474 | iterate_over_lwps (resume_clear_callback, NULL); | |
1475 | ||
1476 | /* If PID is -1, it's the current inferior that should be | |
1477 | handled specially. */ | |
1478 | if (PIDGET (ptid) == -1) | |
1479 | ptid = inferior_ptid; | |
1480 | ||
1481 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1482 | gdb_assert (lp != NULL); |
d6b0e80f | 1483 | |
9f0bdab8 | 1484 | ptid = pid_to_ptid (GET_LWP (lp->ptid)); |
d6b0e80f | 1485 | |
9f0bdab8 DJ |
1486 | /* Remember if we're stepping. */ |
1487 | lp->step = step; | |
d6b0e80f | 1488 | |
9f0bdab8 DJ |
1489 | /* Mark this LWP as resumed. */ |
1490 | lp->resumed = 1; | |
76f50ad1 | 1491 | |
9f0bdab8 DJ |
1492 | /* If we have a pending wait status for this thread, there is no |
1493 | point in resuming the process. But first make sure that | |
1494 | linux_nat_wait won't preemptively handle the event - we | |
1495 | should never take this short-circuit if we are going to | |
1496 | leave LP running, since we have skipped resuming all the | |
1497 | other threads. This bit of code needs to be synchronized | |
1498 | with linux_nat_wait. */ | |
76f50ad1 | 1499 | |
710151dd PA |
1500 | /* In async mode, we never have pending wait status. */ |
1501 | if (target_can_async_p () && lp->status) | |
1502 | internal_error (__FILE__, __LINE__, "Pending status in async mode"); | |
1503 | ||
9f0bdab8 DJ |
1504 | if (lp->status && WIFSTOPPED (lp->status)) |
1505 | { | |
1506 | int saved_signo = target_signal_from_host (WSTOPSIG (lp->status)); | |
76f50ad1 | 1507 | |
9f0bdab8 DJ |
1508 | if (signal_stop_state (saved_signo) == 0 |
1509 | && signal_print_state (saved_signo) == 0 | |
1510 | && signal_pass_state (saved_signo) == 1) | |
d6b0e80f | 1511 | { |
9f0bdab8 DJ |
1512 | if (debug_linux_nat) |
1513 | fprintf_unfiltered (gdb_stdlog, | |
1514 | "LLR: Not short circuiting for ignored " | |
1515 | "status 0x%x\n", lp->status); | |
1516 | ||
d6b0e80f AC |
1517 | /* FIXME: What should we do if we are supposed to continue |
1518 | this thread with a signal? */ | |
1519 | gdb_assert (signo == TARGET_SIGNAL_0); | |
9f0bdab8 DJ |
1520 | signo = saved_signo; |
1521 | lp->status = 0; | |
1522 | } | |
1523 | } | |
76f50ad1 | 1524 | |
9f0bdab8 DJ |
1525 | if (lp->status) |
1526 | { | |
1527 | /* FIXME: What should we do if we are supposed to continue | |
1528 | this thread with a signal? */ | |
1529 | gdb_assert (signo == TARGET_SIGNAL_0); | |
76f50ad1 | 1530 | |
9f0bdab8 DJ |
1531 | if (debug_linux_nat) |
1532 | fprintf_unfiltered (gdb_stdlog, | |
1533 | "LLR: Short circuiting for status 0x%x\n", | |
1534 | lp->status); | |
d6b0e80f | 1535 | |
9f0bdab8 | 1536 | return; |
d6b0e80f AC |
1537 | } |
1538 | ||
9f0bdab8 DJ |
1539 | /* Mark LWP as not stopped to prevent it from being continued by |
1540 | resume_callback. */ | |
1541 | lp->stopped = 0; | |
1542 | ||
d6b0e80f AC |
1543 | if (resume_all) |
1544 | iterate_over_lwps (resume_callback, NULL); | |
1545 | ||
10d6c8cd | 1546 | linux_ops->to_resume (ptid, step, signo); |
9f0bdab8 DJ |
1547 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); |
1548 | ||
d6b0e80f AC |
1549 | if (debug_linux_nat) |
1550 | fprintf_unfiltered (gdb_stdlog, | |
1551 | "LLR: %s %s, %s (resume event thread)\n", | |
1552 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
1553 | target_pid_to_str (ptid), | |
1554 | signo ? strsignal (signo) : "0"); | |
b84876c2 PA |
1555 | |
1556 | if (target_can_async_p ()) | |
1557 | { | |
1558 | target_executing = 1; | |
1559 | target_async (inferior_event_handler, 0); | |
1560 | } | |
d6b0e80f AC |
1561 | } |
1562 | ||
1563 | /* Issue kill to specified lwp. */ | |
1564 | ||
1565 | static int tkill_failed; | |
1566 | ||
1567 | static int | |
1568 | kill_lwp (int lwpid, int signo) | |
1569 | { | |
1570 | errno = 0; | |
1571 | ||
1572 | /* Use tkill, if possible, in case we are using nptl threads. If tkill | |
1573 | fails, then we are not using nptl threads and we should be using kill. */ | |
1574 | ||
1575 | #ifdef HAVE_TKILL_SYSCALL | |
1576 | if (!tkill_failed) | |
1577 | { | |
1578 | int ret = syscall (__NR_tkill, lwpid, signo); | |
1579 | if (errno != ENOSYS) | |
1580 | return ret; | |
1581 | errno = 0; | |
1582 | tkill_failed = 1; | |
1583 | } | |
1584 | #endif | |
1585 | ||
1586 | return kill (lwpid, signo); | |
1587 | } | |
1588 | ||
3d799a95 DJ |
1589 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1590 | event, we need to add the new LWP to our list (and not report the | |
1591 | trap to higher layers). This function returns non-zero if the | |
1592 | event should be ignored and we should wait again. If STOPPING is | |
1593 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1594 | |
1595 | static int | |
3d799a95 DJ |
1596 | linux_handle_extended_wait (struct lwp_info *lp, int status, |
1597 | int stopping) | |
d6b0e80f | 1598 | { |
3d799a95 DJ |
1599 | int pid = GET_LWP (lp->ptid); |
1600 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1601 | struct lwp_info *new_lp = NULL; | |
1602 | int event = status >> 16; | |
d6b0e80f | 1603 | |
3d799a95 DJ |
1604 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1605 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1606 | { |
3d799a95 DJ |
1607 | unsigned long new_pid; |
1608 | int ret; | |
1609 | ||
1610 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1611 | |
3d799a95 DJ |
1612 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1613 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1614 | { | |
1615 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1616 | hits the SIGSTOP, but we're already attached. */ | |
1617 | ret = my_waitpid (new_pid, &status, | |
1618 | (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0); | |
1619 | if (ret == -1) | |
1620 | perror_with_name (_("waiting for new child")); | |
1621 | else if (ret != new_pid) | |
1622 | internal_error (__FILE__, __LINE__, | |
1623 | _("wait returned unexpected PID %d"), ret); | |
1624 | else if (!WIFSTOPPED (status)) | |
1625 | internal_error (__FILE__, __LINE__, | |
1626 | _("wait returned unexpected status 0x%x"), status); | |
1627 | } | |
1628 | ||
1629 | ourstatus->value.related_pid = new_pid; | |
1630 | ||
1631 | if (event == PTRACE_EVENT_FORK) | |
1632 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
1633 | else if (event == PTRACE_EVENT_VFORK) | |
1634 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
6fc19103 | 1635 | else |
3d799a95 DJ |
1636 | { |
1637 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
1638 | new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid))); | |
1639 | new_lp->cloned = 1; | |
d6b0e80f | 1640 | |
3d799a95 DJ |
1641 | if (WSTOPSIG (status) != SIGSTOP) |
1642 | { | |
1643 | /* This can happen if someone starts sending signals to | |
1644 | the new thread before it gets a chance to run, which | |
1645 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
1646 | This is an unlikely case, and harder to handle for | |
1647 | fork / vfork than for clone, so we do not try - but | |
1648 | we handle it for clone events here. We'll send | |
1649 | the other signal on to the thread below. */ | |
1650 | ||
1651 | new_lp->signalled = 1; | |
1652 | } | |
1653 | else | |
1654 | status = 0; | |
d6b0e80f | 1655 | |
3d799a95 DJ |
1656 | if (stopping) |
1657 | new_lp->stopped = 1; | |
1658 | else | |
1659 | { | |
1660 | new_lp->resumed = 1; | |
1661 | ptrace (PTRACE_CONT, lp->waitstatus.value.related_pid, 0, | |
1662 | status ? WSTOPSIG (status) : 0); | |
1663 | } | |
d6b0e80f | 1664 | |
3d799a95 DJ |
1665 | if (debug_linux_nat) |
1666 | fprintf_unfiltered (gdb_stdlog, | |
1667 | "LHEW: Got clone event from LWP %ld, resuming\n", | |
1668 | GET_LWP (lp->ptid)); | |
1669 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1670 | ||
1671 | return 1; | |
1672 | } | |
1673 | ||
1674 | return 0; | |
d6b0e80f AC |
1675 | } |
1676 | ||
3d799a95 DJ |
1677 | if (event == PTRACE_EVENT_EXEC) |
1678 | { | |
1679 | ourstatus->kind = TARGET_WAITKIND_EXECD; | |
1680 | ourstatus->value.execd_pathname | |
6d8fd2b7 | 1681 | = xstrdup (linux_child_pid_to_exec_file (pid)); |
3d799a95 DJ |
1682 | |
1683 | if (linux_parent_pid) | |
1684 | { | |
1685 | detach_breakpoints (linux_parent_pid); | |
1686 | ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0); | |
1687 | ||
1688 | linux_parent_pid = 0; | |
1689 | } | |
1690 | ||
1691 | return 0; | |
1692 | } | |
1693 | ||
1694 | internal_error (__FILE__, __LINE__, | |
1695 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
1696 | } |
1697 | ||
1698 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has | |
1699 | exited. */ | |
1700 | ||
1701 | static int | |
1702 | wait_lwp (struct lwp_info *lp) | |
1703 | { | |
1704 | pid_t pid; | |
1705 | int status; | |
1706 | int thread_dead = 0; | |
1707 | ||
1708 | gdb_assert (!lp->stopped); | |
1709 | gdb_assert (lp->status == 0); | |
1710 | ||
58aecb61 | 1711 | pid = my_waitpid (GET_LWP (lp->ptid), &status, 0); |
d6b0e80f AC |
1712 | if (pid == -1 && errno == ECHILD) |
1713 | { | |
58aecb61 | 1714 | pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE); |
d6b0e80f AC |
1715 | if (pid == -1 && errno == ECHILD) |
1716 | { | |
1717 | /* The thread has previously exited. We need to delete it | |
1718 | now because, for some vendor 2.4 kernels with NPTL | |
1719 | support backported, there won't be an exit event unless | |
1720 | it is the main thread. 2.6 kernels will report an exit | |
1721 | event for each thread that exits, as expected. */ | |
1722 | thread_dead = 1; | |
1723 | if (debug_linux_nat) | |
1724 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
1725 | target_pid_to_str (lp->ptid)); | |
1726 | } | |
1727 | } | |
1728 | ||
1729 | if (!thread_dead) | |
1730 | { | |
1731 | gdb_assert (pid == GET_LWP (lp->ptid)); | |
1732 | ||
1733 | if (debug_linux_nat) | |
1734 | { | |
1735 | fprintf_unfiltered (gdb_stdlog, | |
1736 | "WL: waitpid %s received %s\n", | |
1737 | target_pid_to_str (lp->ptid), | |
1738 | status_to_str (status)); | |
1739 | } | |
1740 | } | |
1741 | ||
1742 | /* Check if the thread has exited. */ | |
1743 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
1744 | { | |
1745 | thread_dead = 1; | |
1746 | if (debug_linux_nat) | |
1747 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
1748 | target_pid_to_str (lp->ptid)); | |
1749 | } | |
1750 | ||
1751 | if (thread_dead) | |
1752 | { | |
e26af52f | 1753 | exit_lwp (lp); |
d6b0e80f AC |
1754 | return 0; |
1755 | } | |
1756 | ||
1757 | gdb_assert (WIFSTOPPED (status)); | |
1758 | ||
1759 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
1760 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
1761 | { | |
1762 | if (debug_linux_nat) | |
1763 | fprintf_unfiltered (gdb_stdlog, | |
1764 | "WL: Handling extended status 0x%06x\n", | |
1765 | status); | |
3d799a95 | 1766 | if (linux_handle_extended_wait (lp, status, 1)) |
d6b0e80f AC |
1767 | return wait_lwp (lp); |
1768 | } | |
1769 | ||
1770 | return status; | |
1771 | } | |
1772 | ||
9f0bdab8 DJ |
1773 | /* Save the most recent siginfo for LP. This is currently only called |
1774 | for SIGTRAP; some ports use the si_addr field for | |
1775 | target_stopped_data_address. In the future, it may also be used to | |
1776 | restore the siginfo of requeued signals. */ | |
1777 | ||
1778 | static void | |
1779 | save_siginfo (struct lwp_info *lp) | |
1780 | { | |
1781 | errno = 0; | |
1782 | ptrace (PTRACE_GETSIGINFO, GET_LWP (lp->ptid), | |
1783 | (PTRACE_TYPE_ARG3) 0, &lp->siginfo); | |
1784 | ||
1785 | if (errno != 0) | |
1786 | memset (&lp->siginfo, 0, sizeof (lp->siginfo)); | |
1787 | } | |
1788 | ||
d6b0e80f AC |
1789 | /* Send a SIGSTOP to LP. */ |
1790 | ||
1791 | static int | |
1792 | stop_callback (struct lwp_info *lp, void *data) | |
1793 | { | |
1794 | if (!lp->stopped && !lp->signalled) | |
1795 | { | |
1796 | int ret; | |
1797 | ||
1798 | if (debug_linux_nat) | |
1799 | { | |
1800 | fprintf_unfiltered (gdb_stdlog, | |
1801 | "SC: kill %s **<SIGSTOP>**\n", | |
1802 | target_pid_to_str (lp->ptid)); | |
1803 | } | |
1804 | errno = 0; | |
1805 | ret = kill_lwp (GET_LWP (lp->ptid), SIGSTOP); | |
1806 | if (debug_linux_nat) | |
1807 | { | |
1808 | fprintf_unfiltered (gdb_stdlog, | |
1809 | "SC: lwp kill %d %s\n", | |
1810 | ret, | |
1811 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
1812 | } | |
1813 | ||
1814 | lp->signalled = 1; | |
1815 | gdb_assert (lp->status == 0); | |
1816 | } | |
1817 | ||
1818 | return 0; | |
1819 | } | |
1820 | ||
1821 | /* Wait until LP is stopped. If DATA is non-null it is interpreted as | |
1822 | a pointer to a set of signals to be flushed immediately. */ | |
1823 | ||
1824 | static int | |
1825 | stop_wait_callback (struct lwp_info *lp, void *data) | |
1826 | { | |
1827 | sigset_t *flush_mask = data; | |
1828 | ||
1829 | if (!lp->stopped) | |
1830 | { | |
1831 | int status; | |
1832 | ||
1833 | status = wait_lwp (lp); | |
1834 | if (status == 0) | |
1835 | return 0; | |
1836 | ||
1837 | /* Ignore any signals in FLUSH_MASK. */ | |
1838 | if (flush_mask && sigismember (flush_mask, WSTOPSIG (status))) | |
1839 | { | |
1840 | if (!lp->signalled) | |
1841 | { | |
1842 | lp->stopped = 1; | |
1843 | return 0; | |
1844 | } | |
1845 | ||
1846 | errno = 0; | |
1847 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1848 | if (debug_linux_nat) | |
1849 | fprintf_unfiltered (gdb_stdlog, | |
1850 | "PTRACE_CONT %s, 0, 0 (%s)\n", | |
1851 | target_pid_to_str (lp->ptid), | |
1852 | errno ? safe_strerror (errno) : "OK"); | |
1853 | ||
1854 | return stop_wait_callback (lp, flush_mask); | |
1855 | } | |
1856 | ||
1857 | if (WSTOPSIG (status) != SIGSTOP) | |
1858 | { | |
1859 | if (WSTOPSIG (status) == SIGTRAP) | |
1860 | { | |
1861 | /* If a LWP other than the LWP that we're reporting an | |
1862 | event for has hit a GDB breakpoint (as opposed to | |
1863 | some random trap signal), then just arrange for it to | |
1864 | hit it again later. We don't keep the SIGTRAP status | |
1865 | and don't forward the SIGTRAP signal to the LWP. We | |
1866 | will handle the current event, eventually we will | |
1867 | resume all LWPs, and this one will get its breakpoint | |
1868 | trap again. | |
1869 | ||
1870 | If we do not do this, then we run the risk that the | |
1871 | user will delete or disable the breakpoint, but the | |
1872 | thread will have already tripped on it. */ | |
1873 | ||
9f0bdab8 DJ |
1874 | /* Save the trap's siginfo in case we need it later. */ |
1875 | save_siginfo (lp); | |
1876 | ||
d6b0e80f AC |
1877 | /* Now resume this LWP and get the SIGSTOP event. */ |
1878 | errno = 0; | |
1879 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1880 | if (debug_linux_nat) | |
1881 | { | |
1882 | fprintf_unfiltered (gdb_stdlog, | |
1883 | "PTRACE_CONT %s, 0, 0 (%s)\n", | |
1884 | target_pid_to_str (lp->ptid), | |
1885 | errno ? safe_strerror (errno) : "OK"); | |
1886 | ||
1887 | fprintf_unfiltered (gdb_stdlog, | |
1888 | "SWC: Candidate SIGTRAP event in %s\n", | |
1889 | target_pid_to_str (lp->ptid)); | |
1890 | } | |
710151dd PA |
1891 | /* Hold this event/waitstatus while we check to see if |
1892 | there are any more (we still want to get that SIGSTOP). */ | |
d6b0e80f | 1893 | stop_wait_callback (lp, data); |
710151dd PA |
1894 | |
1895 | if (target_can_async_p ()) | |
d6b0e80f | 1896 | { |
710151dd PA |
1897 | /* Don't leave a pending wait status in async mode. |
1898 | Retrigger the breakpoint. */ | |
1899 | if (!cancel_breakpoint (lp)) | |
d6b0e80f | 1900 | { |
710151dd PA |
1901 | /* There was no gdb breakpoint set at pc. Put |
1902 | the event back in the queue. */ | |
1903 | if (debug_linux_nat) | |
1904 | fprintf_unfiltered (gdb_stdlog, | |
1905 | "SWC: kill %s, %s\n", | |
1906 | target_pid_to_str (lp->ptid), | |
1907 | status_to_str ((int) status)); | |
1908 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
1909 | } | |
1910 | } | |
1911 | else | |
1912 | { | |
1913 | /* Hold the SIGTRAP for handling by | |
1914 | linux_nat_wait. */ | |
1915 | /* If there's another event, throw it back into the | |
1916 | queue. */ | |
1917 | if (lp->status) | |
1918 | { | |
1919 | if (debug_linux_nat) | |
1920 | fprintf_unfiltered (gdb_stdlog, | |
1921 | "SWC: kill %s, %s\n", | |
1922 | target_pid_to_str (lp->ptid), | |
1923 | status_to_str ((int) status)); | |
1924 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status)); | |
d6b0e80f | 1925 | } |
710151dd PA |
1926 | /* Save the sigtrap event. */ |
1927 | lp->status = status; | |
d6b0e80f | 1928 | } |
d6b0e80f AC |
1929 | return 0; |
1930 | } | |
1931 | else | |
1932 | { | |
1933 | /* The thread was stopped with a signal other than | |
1934 | SIGSTOP, and didn't accidentally trip a breakpoint. */ | |
1935 | ||
1936 | if (debug_linux_nat) | |
1937 | { | |
1938 | fprintf_unfiltered (gdb_stdlog, | |
1939 | "SWC: Pending event %s in %s\n", | |
1940 | status_to_str ((int) status), | |
1941 | target_pid_to_str (lp->ptid)); | |
1942 | } | |
1943 | /* Now resume this LWP and get the SIGSTOP event. */ | |
1944 | errno = 0; | |
1945 | ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
1946 | if (debug_linux_nat) | |
1947 | fprintf_unfiltered (gdb_stdlog, | |
1948 | "SWC: PTRACE_CONT %s, 0, 0 (%s)\n", | |
1949 | target_pid_to_str (lp->ptid), | |
1950 | errno ? safe_strerror (errno) : "OK"); | |
1951 | ||
1952 | /* Hold this event/waitstatus while we check to see if | |
1953 | there are any more (we still want to get that SIGSTOP). */ | |
1954 | stop_wait_callback (lp, data); | |
710151dd PA |
1955 | |
1956 | /* If the lp->status field is still empty, use it to | |
1957 | hold this event. If not, then this event must be | |
1958 | returned to the event queue of the LWP. */ | |
1959 | if (lp->status || target_can_async_p ()) | |
d6b0e80f AC |
1960 | { |
1961 | if (debug_linux_nat) | |
1962 | { | |
1963 | fprintf_unfiltered (gdb_stdlog, | |
1964 | "SWC: kill %s, %s\n", | |
1965 | target_pid_to_str (lp->ptid), | |
1966 | status_to_str ((int) status)); | |
1967 | } | |
1968 | kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status)); | |
1969 | } | |
710151dd PA |
1970 | else |
1971 | lp->status = status; | |
d6b0e80f AC |
1972 | return 0; |
1973 | } | |
1974 | } | |
1975 | else | |
1976 | { | |
1977 | /* We caught the SIGSTOP that we intended to catch, so | |
1978 | there's no SIGSTOP pending. */ | |
1979 | lp->stopped = 1; | |
1980 | lp->signalled = 0; | |
1981 | } | |
1982 | } | |
1983 | ||
1984 | return 0; | |
1985 | } | |
1986 | ||
1987 | /* Check whether PID has any pending signals in FLUSH_MASK. If so set | |
1988 | the appropriate bits in PENDING, and return 1 - otherwise return 0. */ | |
1989 | ||
1990 | static int | |
1991 | linux_nat_has_pending (int pid, sigset_t *pending, sigset_t *flush_mask) | |
1992 | { | |
1993 | sigset_t blocked, ignored; | |
1994 | int i; | |
1995 | ||
1996 | linux_proc_pending_signals (pid, pending, &blocked, &ignored); | |
1997 | ||
1998 | if (!flush_mask) | |
1999 | return 0; | |
2000 | ||
2001 | for (i = 1; i < NSIG; i++) | |
2002 | if (sigismember (pending, i)) | |
2003 | if (!sigismember (flush_mask, i) | |
2004 | || sigismember (&blocked, i) | |
2005 | || sigismember (&ignored, i)) | |
2006 | sigdelset (pending, i); | |
2007 | ||
2008 | if (sigisemptyset (pending)) | |
2009 | return 0; | |
2010 | ||
2011 | return 1; | |
2012 | } | |
2013 | ||
2014 | /* DATA is interpreted as a mask of signals to flush. If LP has | |
2015 | signals pending, and they are all in the flush mask, then arrange | |
2016 | to flush them. LP should be stopped, as should all other threads | |
2017 | it might share a signal queue with. */ | |
2018 | ||
2019 | static int | |
2020 | flush_callback (struct lwp_info *lp, void *data) | |
2021 | { | |
2022 | sigset_t *flush_mask = data; | |
2023 | sigset_t pending, intersection, blocked, ignored; | |
2024 | int pid, status; | |
2025 | ||
2026 | /* Normally, when an LWP exits, it is removed from the LWP list. The | |
2027 | last LWP isn't removed till later, however. So if there is only | |
2028 | one LWP on the list, make sure it's alive. */ | |
2029 | if (lwp_list == lp && lp->next == NULL) | |
2030 | if (!linux_nat_thread_alive (lp->ptid)) | |
2031 | return 0; | |
2032 | ||
2033 | /* Just because the LWP is stopped doesn't mean that new signals | |
2034 | can't arrive from outside, so this function must be careful of | |
2035 | race conditions. However, because all threads are stopped, we | |
2036 | can assume that the pending mask will not shrink unless we resume | |
2037 | the LWP, and that it will then get another signal. We can't | |
2038 | control which one, however. */ | |
2039 | ||
2040 | if (lp->status) | |
2041 | { | |
2042 | if (debug_linux_nat) | |
a3f17187 | 2043 | printf_unfiltered (_("FC: LP has pending status %06x\n"), lp->status); |
d6b0e80f AC |
2044 | if (WIFSTOPPED (lp->status) && sigismember (flush_mask, WSTOPSIG (lp->status))) |
2045 | lp->status = 0; | |
2046 | } | |
2047 | ||
3d799a95 DJ |
2048 | /* While there is a pending signal we would like to flush, continue |
2049 | the inferior and collect another signal. But if there's already | |
2050 | a saved status that we don't want to flush, we can't resume the | |
2051 | inferior - if it stopped for some other reason we wouldn't have | |
2052 | anywhere to save the new status. In that case, we must leave the | |
2053 | signal unflushed (and possibly generate an extra SIGINT stop). | |
2054 | That's much less bad than losing a signal. */ | |
2055 | while (lp->status == 0 | |
2056 | && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask)) | |
d6b0e80f AC |
2057 | { |
2058 | int ret; | |
2059 | ||
2060 | errno = 0; | |
2061 | ret = ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); | |
2062 | if (debug_linux_nat) | |
2063 | fprintf_unfiltered (gdb_stderr, | |
2064 | "FC: Sent PTRACE_CONT, ret %d %d\n", ret, errno); | |
2065 | ||
2066 | lp->stopped = 0; | |
2067 | stop_wait_callback (lp, flush_mask); | |
2068 | if (debug_linux_nat) | |
2069 | fprintf_unfiltered (gdb_stderr, | |
2070 | "FC: Wait finished; saved status is %d\n", | |
2071 | lp->status); | |
2072 | } | |
2073 | ||
2074 | return 0; | |
2075 | } | |
2076 | ||
2077 | /* Return non-zero if LP has a wait status pending. */ | |
2078 | ||
2079 | static int | |
2080 | status_callback (struct lwp_info *lp, void *data) | |
2081 | { | |
2082 | /* Only report a pending wait status if we pretend that this has | |
2083 | indeed been resumed. */ | |
2084 | return (lp->status != 0 && lp->resumed); | |
2085 | } | |
2086 | ||
2087 | /* Return non-zero if LP isn't stopped. */ | |
2088 | ||
2089 | static int | |
2090 | running_callback (struct lwp_info *lp, void *data) | |
2091 | { | |
2092 | return (lp->stopped == 0 || (lp->status != 0 && lp->resumed)); | |
2093 | } | |
2094 | ||
2095 | /* Count the LWP's that have had events. */ | |
2096 | ||
2097 | static int | |
2098 | count_events_callback (struct lwp_info *lp, void *data) | |
2099 | { | |
2100 | int *count = data; | |
2101 | ||
2102 | gdb_assert (count != NULL); | |
2103 | ||
2104 | /* Count only LWPs that have a SIGTRAP event pending. */ | |
2105 | if (lp->status != 0 | |
2106 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) | |
2107 | (*count)++; | |
2108 | ||
2109 | return 0; | |
2110 | } | |
2111 | ||
2112 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2113 | ||
2114 | static int | |
2115 | select_singlestep_lwp_callback (struct lwp_info *lp, void *data) | |
2116 | { | |
2117 | if (lp->step && lp->status != 0) | |
2118 | return 1; | |
2119 | else | |
2120 | return 0; | |
2121 | } | |
2122 | ||
2123 | /* Select the Nth LWP that has had a SIGTRAP event. */ | |
2124 | ||
2125 | static int | |
2126 | select_event_lwp_callback (struct lwp_info *lp, void *data) | |
2127 | { | |
2128 | int *selector = data; | |
2129 | ||
2130 | gdb_assert (selector != NULL); | |
2131 | ||
2132 | /* Select only LWPs that have a SIGTRAP event pending. */ | |
2133 | if (lp->status != 0 | |
2134 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP) | |
2135 | if ((*selector)-- == 0) | |
2136 | return 1; | |
2137 | ||
2138 | return 0; | |
2139 | } | |
2140 | ||
710151dd PA |
2141 | static int |
2142 | cancel_breakpoint (struct lwp_info *lp) | |
2143 | { | |
2144 | /* Arrange for a breakpoint to be hit again later. We don't keep | |
2145 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2146 | LWP. We will handle the current event, eventually we will resume | |
2147 | this LWP, and this breakpoint will trap again. | |
2148 | ||
2149 | If we do not do this, then we run the risk that the user will | |
2150 | delete or disable the breakpoint, but the LWP will have already | |
2151 | tripped on it. */ | |
2152 | ||
515630c5 UW |
2153 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
2154 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
2155 | CORE_ADDR pc; | |
2156 | ||
2157 | pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch); | |
2158 | if (breakpoint_inserted_here_p (pc)) | |
710151dd PA |
2159 | { |
2160 | if (debug_linux_nat) | |
2161 | fprintf_unfiltered (gdb_stdlog, | |
2162 | "CB: Push back breakpoint for %s\n", | |
2163 | target_pid_to_str (lp->ptid)); | |
2164 | ||
2165 | /* Back up the PC if necessary. */ | |
515630c5 UW |
2166 | if (gdbarch_decr_pc_after_break (gdbarch)) |
2167 | regcache_write_pc (regcache, pc); | |
2168 | ||
710151dd PA |
2169 | return 1; |
2170 | } | |
2171 | return 0; | |
2172 | } | |
2173 | ||
d6b0e80f AC |
2174 | static int |
2175 | cancel_breakpoints_callback (struct lwp_info *lp, void *data) | |
2176 | { | |
2177 | struct lwp_info *event_lp = data; | |
2178 | ||
2179 | /* Leave the LWP that has been elected to receive a SIGTRAP alone. */ | |
2180 | if (lp == event_lp) | |
2181 | return 0; | |
2182 | ||
2183 | /* If a LWP other than the LWP that we're reporting an event for has | |
2184 | hit a GDB breakpoint (as opposed to some random trap signal), | |
2185 | then just arrange for it to hit it again later. We don't keep | |
2186 | the SIGTRAP status and don't forward the SIGTRAP signal to the | |
2187 | LWP. We will handle the current event, eventually we will resume | |
2188 | all LWPs, and this one will get its breakpoint trap again. | |
2189 | ||
2190 | If we do not do this, then we run the risk that the user will | |
2191 | delete or disable the breakpoint, but the LWP will have already | |
2192 | tripped on it. */ | |
2193 | ||
2194 | if (lp->status != 0 | |
2195 | && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP | |
710151dd PA |
2196 | && cancel_breakpoint (lp)) |
2197 | /* Throw away the SIGTRAP. */ | |
2198 | lp->status = 0; | |
d6b0e80f AC |
2199 | |
2200 | return 0; | |
2201 | } | |
2202 | ||
2203 | /* Select one LWP out of those that have events pending. */ | |
2204 | ||
2205 | static void | |
2206 | select_event_lwp (struct lwp_info **orig_lp, int *status) | |
2207 | { | |
2208 | int num_events = 0; | |
2209 | int random_selector; | |
2210 | struct lwp_info *event_lp; | |
2211 | ||
ac264b3b | 2212 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2213 | (*orig_lp)->status = *status; |
2214 | ||
2215 | /* Give preference to any LWP that is being single-stepped. */ | |
2216 | event_lp = iterate_over_lwps (select_singlestep_lwp_callback, NULL); | |
2217 | if (event_lp != NULL) | |
2218 | { | |
2219 | if (debug_linux_nat) | |
2220 | fprintf_unfiltered (gdb_stdlog, | |
2221 | "SEL: Select single-step %s\n", | |
2222 | target_pid_to_str (event_lp->ptid)); | |
2223 | } | |
2224 | else | |
2225 | { | |
2226 | /* No single-stepping LWP. Select one at random, out of those | |
2227 | which have had SIGTRAP events. */ | |
2228 | ||
2229 | /* First see how many SIGTRAP events we have. */ | |
2230 | iterate_over_lwps (count_events_callback, &num_events); | |
2231 | ||
2232 | /* Now randomly pick a LWP out of those that have had a SIGTRAP. */ | |
2233 | random_selector = (int) | |
2234 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2235 | ||
2236 | if (debug_linux_nat && num_events > 1) | |
2237 | fprintf_unfiltered (gdb_stdlog, | |
2238 | "SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2239 | num_events, random_selector); | |
2240 | ||
2241 | event_lp = iterate_over_lwps (select_event_lwp_callback, | |
2242 | &random_selector); | |
2243 | } | |
2244 | ||
2245 | if (event_lp != NULL) | |
2246 | { | |
2247 | /* Switch the event LWP. */ | |
2248 | *orig_lp = event_lp; | |
2249 | *status = event_lp->status; | |
2250 | } | |
2251 | ||
2252 | /* Flush the wait status for the event LWP. */ | |
2253 | (*orig_lp)->status = 0; | |
2254 | } | |
2255 | ||
2256 | /* Return non-zero if LP has been resumed. */ | |
2257 | ||
2258 | static int | |
2259 | resumed_callback (struct lwp_info *lp, void *data) | |
2260 | { | |
2261 | return lp->resumed; | |
2262 | } | |
2263 | ||
d6b0e80f AC |
2264 | /* Stop an active thread, verify it still exists, then resume it. */ |
2265 | ||
2266 | static int | |
2267 | stop_and_resume_callback (struct lwp_info *lp, void *data) | |
2268 | { | |
2269 | struct lwp_info *ptr; | |
2270 | ||
2271 | if (!lp->stopped && !lp->signalled) | |
2272 | { | |
2273 | stop_callback (lp, NULL); | |
2274 | stop_wait_callback (lp, NULL); | |
2275 | /* Resume if the lwp still exists. */ | |
2276 | for (ptr = lwp_list; ptr; ptr = ptr->next) | |
2277 | if (lp == ptr) | |
2278 | { | |
2279 | resume_callback (lp, NULL); | |
2280 | resume_set_callback (lp, NULL); | |
2281 | } | |
2282 | } | |
2283 | return 0; | |
2284 | } | |
2285 | ||
02f3fc28 | 2286 | /* Check if we should go on and pass this event to common code. |
fa2c6a57 | 2287 | Return the affected lwp if we are, or NULL otherwise. */ |
02f3fc28 PA |
2288 | static struct lwp_info * |
2289 | linux_nat_filter_event (int lwpid, int status, int options) | |
2290 | { | |
2291 | struct lwp_info *lp; | |
2292 | ||
2293 | lp = find_lwp_pid (pid_to_ptid (lwpid)); | |
2294 | ||
2295 | /* Check for stop events reported by a process we didn't already | |
2296 | know about - anything not already in our LWP list. | |
2297 | ||
2298 | If we're expecting to receive stopped processes after | |
2299 | fork, vfork, and clone events, then we'll just add the | |
2300 | new one to our list and go back to waiting for the event | |
2301 | to be reported - the stopped process might be returned | |
2302 | from waitpid before or after the event is. */ | |
2303 | if (WIFSTOPPED (status) && !lp) | |
2304 | { | |
2305 | linux_record_stopped_pid (lwpid, status); | |
2306 | return NULL; | |
2307 | } | |
2308 | ||
2309 | /* Make sure we don't report an event for the exit of an LWP not in | |
2310 | our list, i.e. not part of the current process. This can happen | |
2311 | if we detach from a program we original forked and then it | |
2312 | exits. */ | |
2313 | if (!WIFSTOPPED (status) && !lp) | |
2314 | return NULL; | |
2315 | ||
2316 | /* NOTE drow/2003-06-17: This code seems to be meant for debugging | |
2317 | CLONE_PTRACE processes which do not use the thread library - | |
2318 | otherwise we wouldn't find the new LWP this way. That doesn't | |
2319 | currently work, and the following code is currently unreachable | |
2320 | due to the two blocks above. If it's fixed some day, this code | |
2321 | should be broken out into a function so that we can also pick up | |
2322 | LWPs from the new interface. */ | |
2323 | if (!lp) | |
2324 | { | |
2325 | lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid))); | |
2326 | if (options & __WCLONE) | |
2327 | lp->cloned = 1; | |
2328 | ||
2329 | gdb_assert (WIFSTOPPED (status) | |
2330 | && WSTOPSIG (status) == SIGSTOP); | |
2331 | lp->signalled = 1; | |
2332 | ||
2333 | if (!in_thread_list (inferior_ptid)) | |
2334 | { | |
2335 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2336 | GET_PID (inferior_ptid)); | |
2337 | add_thread (inferior_ptid); | |
2338 | } | |
2339 | ||
2340 | add_thread (lp->ptid); | |
2341 | } | |
2342 | ||
2343 | /* Save the trap's siginfo in case we need it later. */ | |
2344 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) | |
2345 | save_siginfo (lp); | |
2346 | ||
2347 | /* Handle GNU/Linux's extended waitstatus for trace events. */ | |
2348 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0) | |
2349 | { | |
2350 | if (debug_linux_nat) | |
2351 | fprintf_unfiltered (gdb_stdlog, | |
2352 | "LLW: Handling extended status 0x%06x\n", | |
2353 | status); | |
2354 | if (linux_handle_extended_wait (lp, status, 0)) | |
2355 | return NULL; | |
2356 | } | |
2357 | ||
2358 | /* Check if the thread has exited. */ | |
2359 | if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1) | |
2360 | { | |
2361 | /* If this is the main thread, we must stop all threads and | |
2362 | verify if they are still alive. This is because in the nptl | |
2363 | thread model, there is no signal issued for exiting LWPs | |
2364 | other than the main thread. We only get the main thread exit | |
2365 | signal once all child threads have already exited. If we | |
2366 | stop all the threads and use the stop_wait_callback to check | |
2367 | if they have exited we can determine whether this signal | |
2368 | should be ignored or whether it means the end of the debugged | |
2369 | application, regardless of which threading model is being | |
2370 | used. */ | |
2371 | if (GET_PID (lp->ptid) == GET_LWP (lp->ptid)) | |
2372 | { | |
2373 | lp->stopped = 1; | |
2374 | iterate_over_lwps (stop_and_resume_callback, NULL); | |
2375 | } | |
2376 | ||
2377 | if (debug_linux_nat) | |
2378 | fprintf_unfiltered (gdb_stdlog, | |
2379 | "LLW: %s exited.\n", | |
2380 | target_pid_to_str (lp->ptid)); | |
2381 | ||
2382 | exit_lwp (lp); | |
2383 | ||
2384 | /* If there is at least one more LWP, then the exit signal was | |
2385 | not the end of the debugged application and should be | |
2386 | ignored. */ | |
2387 | if (num_lwps > 0) | |
2388 | { | |
2389 | /* Make sure there is at least one thread running. */ | |
2390 | gdb_assert (iterate_over_lwps (running_callback, NULL)); | |
2391 | ||
2392 | /* Discard the event. */ | |
2393 | return NULL; | |
2394 | } | |
2395 | } | |
2396 | ||
2397 | /* Check if the current LWP has previously exited. In the nptl | |
2398 | thread model, LWPs other than the main thread do not issue | |
2399 | signals when they exit so we must check whenever the thread has | |
2400 | stopped. A similar check is made in stop_wait_callback(). */ | |
2401 | if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid)) | |
2402 | { | |
2403 | if (debug_linux_nat) | |
2404 | fprintf_unfiltered (gdb_stdlog, | |
2405 | "LLW: %s exited.\n", | |
2406 | target_pid_to_str (lp->ptid)); | |
2407 | ||
2408 | exit_lwp (lp); | |
2409 | ||
2410 | /* Make sure there is at least one thread running. */ | |
2411 | gdb_assert (iterate_over_lwps (running_callback, NULL)); | |
2412 | ||
2413 | /* Discard the event. */ | |
2414 | return NULL; | |
2415 | } | |
2416 | ||
2417 | /* Make sure we don't report a SIGSTOP that we sent ourselves in | |
2418 | an attempt to stop an LWP. */ | |
2419 | if (lp->signalled | |
2420 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
2421 | { | |
2422 | if (debug_linux_nat) | |
2423 | fprintf_unfiltered (gdb_stdlog, | |
2424 | "LLW: Delayed SIGSTOP caught for %s.\n", | |
2425 | target_pid_to_str (lp->ptid)); | |
2426 | ||
2427 | /* This is a delayed SIGSTOP. */ | |
2428 | lp->signalled = 0; | |
2429 | ||
2430 | registers_changed (); | |
2431 | ||
2432 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), | |
2433 | lp->step, TARGET_SIGNAL_0); | |
2434 | if (debug_linux_nat) | |
2435 | fprintf_unfiltered (gdb_stdlog, | |
2436 | "LLW: %s %s, 0, 0 (discard SIGSTOP)\n", | |
2437 | lp->step ? | |
2438 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2439 | target_pid_to_str (lp->ptid)); | |
2440 | ||
2441 | lp->stopped = 0; | |
2442 | gdb_assert (lp->resumed); | |
2443 | ||
2444 | /* Discard the event. */ | |
2445 | return NULL; | |
2446 | } | |
2447 | ||
2448 | /* An interesting event. */ | |
2449 | gdb_assert (lp); | |
2450 | return lp; | |
2451 | } | |
2452 | ||
b84876c2 PA |
2453 | /* Get the events stored in the pipe into the local queue, so they are |
2454 | accessible to queued_waitpid. We need to do this, since it is not | |
2455 | always the case that the event at the head of the pipe is the event | |
2456 | we want. */ | |
2457 | ||
2458 | static void | |
2459 | pipe_to_local_event_queue (void) | |
2460 | { | |
2461 | if (debug_linux_nat_async) | |
2462 | fprintf_unfiltered (gdb_stdlog, | |
2463 | "PTLEQ: linux_nat_num_queued_events(%d)\n", | |
2464 | linux_nat_num_queued_events); | |
2465 | while (linux_nat_num_queued_events) | |
2466 | { | |
2467 | int lwpid, status, options; | |
b84876c2 | 2468 | lwpid = linux_nat_event_pipe_pop (&status, &options); |
b84876c2 PA |
2469 | gdb_assert (lwpid > 0); |
2470 | push_waitpid (lwpid, status, options); | |
2471 | } | |
2472 | } | |
2473 | ||
2474 | /* Get the unprocessed events stored in the local queue back into the | |
2475 | pipe, so the event loop realizes there's something else to | |
2476 | process. */ | |
2477 | ||
2478 | static void | |
2479 | local_event_queue_to_pipe (void) | |
2480 | { | |
2481 | struct waitpid_result *w = waitpid_queue; | |
2482 | while (w) | |
2483 | { | |
2484 | struct waitpid_result *next = w->next; | |
2485 | linux_nat_event_pipe_push (w->pid, | |
2486 | w->status, | |
2487 | w->options); | |
2488 | xfree (w); | |
2489 | w = next; | |
2490 | } | |
2491 | waitpid_queue = NULL; | |
2492 | ||
2493 | if (debug_linux_nat_async) | |
2494 | fprintf_unfiltered (gdb_stdlog, | |
2495 | "LEQTP: linux_nat_num_queued_events(%d)\n", | |
2496 | linux_nat_num_queued_events); | |
2497 | } | |
2498 | ||
d6b0e80f AC |
2499 | static ptid_t |
2500 | linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
2501 | { | |
2502 | struct lwp_info *lp = NULL; | |
2503 | int options = 0; | |
2504 | int status = 0; | |
2505 | pid_t pid = PIDGET (ptid); | |
2506 | sigset_t flush_mask; | |
2507 | ||
b84876c2 PA |
2508 | if (debug_linux_nat_async) |
2509 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); | |
2510 | ||
f973ed9c DJ |
2511 | /* The first time we get here after starting a new inferior, we may |
2512 | not have added it to the LWP list yet - this is the earliest | |
2513 | moment at which we know its PID. */ | |
2514 | if (num_lwps == 0) | |
2515 | { | |
2516 | gdb_assert (!is_lwp (inferior_ptid)); | |
2517 | ||
2518 | inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), | |
2519 | GET_PID (inferior_ptid)); | |
2520 | lp = add_lwp (inferior_ptid); | |
2521 | lp->resumed = 1; | |
403fe197 PA |
2522 | /* Add the main thread to GDB's thread list. */ |
2523 | add_thread_silent (lp->ptid); | |
f973ed9c DJ |
2524 | } |
2525 | ||
d6b0e80f AC |
2526 | sigemptyset (&flush_mask); |
2527 | ||
b84876c2 PA |
2528 | if (target_can_async_p ()) |
2529 | /* Block events while we're here. */ | |
2530 | target_async (NULL, 0); | |
d6b0e80f AC |
2531 | |
2532 | retry: | |
2533 | ||
f973ed9c DJ |
2534 | /* Make sure there is at least one LWP that has been resumed. */ |
2535 | gdb_assert (iterate_over_lwps (resumed_callback, NULL)); | |
d6b0e80f AC |
2536 | |
2537 | /* First check if there is a LWP with a wait status pending. */ | |
2538 | if (pid == -1) | |
2539 | { | |
2540 | /* Any LWP that's been resumed will do. */ | |
2541 | lp = iterate_over_lwps (status_callback, NULL); | |
2542 | if (lp) | |
2543 | { | |
710151dd PA |
2544 | if (target_can_async_p ()) |
2545 | internal_error (__FILE__, __LINE__, | |
2546 | "Found an LWP with a pending status in async mode."); | |
2547 | ||
d6b0e80f AC |
2548 | status = lp->status; |
2549 | lp->status = 0; | |
2550 | ||
2551 | if (debug_linux_nat && status) | |
2552 | fprintf_unfiltered (gdb_stdlog, | |
2553 | "LLW: Using pending wait status %s for %s.\n", | |
2554 | status_to_str (status), | |
2555 | target_pid_to_str (lp->ptid)); | |
2556 | } | |
2557 | ||
b84876c2 | 2558 | /* But if we don't find one, we'll have to wait, and check both |
d6b0e80f AC |
2559 | cloned and uncloned processes. We start with the cloned |
2560 | processes. */ | |
2561 | options = __WCLONE | WNOHANG; | |
2562 | } | |
2563 | else if (is_lwp (ptid)) | |
2564 | { | |
2565 | if (debug_linux_nat) | |
2566 | fprintf_unfiltered (gdb_stdlog, | |
2567 | "LLW: Waiting for specific LWP %s.\n", | |
2568 | target_pid_to_str (ptid)); | |
2569 | ||
2570 | /* We have a specific LWP to check. */ | |
2571 | lp = find_lwp_pid (ptid); | |
2572 | gdb_assert (lp); | |
2573 | status = lp->status; | |
2574 | lp->status = 0; | |
2575 | ||
2576 | if (debug_linux_nat && status) | |
2577 | fprintf_unfiltered (gdb_stdlog, | |
2578 | "LLW: Using pending wait status %s for %s.\n", | |
2579 | status_to_str (status), | |
2580 | target_pid_to_str (lp->ptid)); | |
2581 | ||
2582 | /* If we have to wait, take into account whether PID is a cloned | |
2583 | process or not. And we have to convert it to something that | |
2584 | the layer beneath us can understand. */ | |
2585 | options = lp->cloned ? __WCLONE : 0; | |
2586 | pid = GET_LWP (ptid); | |
2587 | } | |
2588 | ||
2589 | if (status && lp->signalled) | |
2590 | { | |
2591 | /* A pending SIGSTOP may interfere with the normal stream of | |
2592 | events. In a typical case where interference is a problem, | |
2593 | we have a SIGSTOP signal pending for LWP A while | |
2594 | single-stepping it, encounter an event in LWP B, and take the | |
2595 | pending SIGSTOP while trying to stop LWP A. After processing | |
2596 | the event in LWP B, LWP A is continued, and we'll never see | |
2597 | the SIGTRAP associated with the last time we were | |
2598 | single-stepping LWP A. */ | |
2599 | ||
2600 | /* Resume the thread. It should halt immediately returning the | |
2601 | pending SIGSTOP. */ | |
2602 | registers_changed (); | |
10d6c8cd DJ |
2603 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2604 | lp->step, TARGET_SIGNAL_0); | |
d6b0e80f AC |
2605 | if (debug_linux_nat) |
2606 | fprintf_unfiltered (gdb_stdlog, | |
2607 | "LLW: %s %s, 0, 0 (expect SIGSTOP)\n", | |
2608 | lp->step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2609 | target_pid_to_str (lp->ptid)); | |
2610 | lp->stopped = 0; | |
2611 | gdb_assert (lp->resumed); | |
2612 | ||
2613 | /* This should catch the pending SIGSTOP. */ | |
2614 | stop_wait_callback (lp, NULL); | |
2615 | } | |
2616 | ||
b84876c2 PA |
2617 | if (!target_can_async_p ()) |
2618 | { | |
2619 | /* Causes SIGINT to be passed on to the attached process. */ | |
2620 | set_sigint_trap (); | |
2621 | set_sigio_trap (); | |
2622 | } | |
d6b0e80f AC |
2623 | |
2624 | while (status == 0) | |
2625 | { | |
2626 | pid_t lwpid; | |
2627 | ||
b84876c2 PA |
2628 | if (target_can_async_p ()) |
2629 | /* In async mode, don't ever block. Only look at the locally | |
2630 | queued events. */ | |
2631 | lwpid = queued_waitpid (pid, &status, options); | |
2632 | else | |
2633 | lwpid = my_waitpid (pid, &status, options); | |
2634 | ||
d6b0e80f AC |
2635 | if (lwpid > 0) |
2636 | { | |
2637 | gdb_assert (pid == -1 || lwpid == pid); | |
2638 | ||
2639 | if (debug_linux_nat) | |
2640 | { | |
2641 | fprintf_unfiltered (gdb_stdlog, | |
2642 | "LLW: waitpid %ld received %s\n", | |
2643 | (long) lwpid, status_to_str (status)); | |
2644 | } | |
2645 | ||
02f3fc28 | 2646 | lp = linux_nat_filter_event (lwpid, status, options); |
d6b0e80f AC |
2647 | if (!lp) |
2648 | { | |
02f3fc28 | 2649 | /* A discarded event. */ |
d6b0e80f AC |
2650 | status = 0; |
2651 | continue; | |
2652 | } | |
2653 | ||
2654 | break; | |
2655 | } | |
2656 | ||
2657 | if (pid == -1) | |
2658 | { | |
2659 | /* Alternate between checking cloned and uncloned processes. */ | |
2660 | options ^= __WCLONE; | |
2661 | ||
b84876c2 PA |
2662 | /* And every time we have checked both: |
2663 | In async mode, return to event loop; | |
2664 | In sync mode, suspend waiting for a SIGCHLD signal. */ | |
d6b0e80f | 2665 | if (options & __WCLONE) |
b84876c2 PA |
2666 | { |
2667 | if (target_can_async_p ()) | |
2668 | { | |
2669 | /* No interesting event. */ | |
2670 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
2671 | ||
2672 | /* Get ready for the next event. */ | |
2673 | target_async (inferior_event_handler, 0); | |
2674 | ||
2675 | if (debug_linux_nat_async) | |
2676 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); | |
2677 | ||
2678 | return minus_one_ptid; | |
2679 | } | |
2680 | ||
2681 | sigsuspend (&suspend_mask); | |
2682 | } | |
d6b0e80f AC |
2683 | } |
2684 | ||
2685 | /* We shouldn't end up here unless we want to try again. */ | |
2686 | gdb_assert (status == 0); | |
2687 | } | |
2688 | ||
b84876c2 PA |
2689 | if (!target_can_async_p ()) |
2690 | { | |
2691 | clear_sigio_trap (); | |
2692 | clear_sigint_trap (); | |
2693 | } | |
d6b0e80f AC |
2694 | |
2695 | gdb_assert (lp); | |
2696 | ||
2697 | /* Don't report signals that GDB isn't interested in, such as | |
2698 | signals that are neither printed nor stopped upon. Stopping all | |
2699 | threads can be a bit time-consuming so if we want decent | |
2700 | performance with heavily multi-threaded programs, especially when | |
2701 | they're using a high frequency timer, we'd better avoid it if we | |
2702 | can. */ | |
2703 | ||
2704 | if (WIFSTOPPED (status)) | |
2705 | { | |
2706 | int signo = target_signal_from_host (WSTOPSIG (status)); | |
2707 | ||
d539ed7e UW |
2708 | /* If we get a signal while single-stepping, we may need special |
2709 | care, e.g. to skip the signal handler. Defer to common code. */ | |
2710 | if (!lp->step | |
2711 | && signal_stop_state (signo) == 0 | |
d6b0e80f AC |
2712 | && signal_print_state (signo) == 0 |
2713 | && signal_pass_state (signo) == 1) | |
2714 | { | |
2715 | /* FIMXE: kettenis/2001-06-06: Should we resume all threads | |
2716 | here? It is not clear we should. GDB may not expect | |
2717 | other threads to run. On the other hand, not resuming | |
2718 | newly attached threads may cause an unwanted delay in | |
2719 | getting them running. */ | |
2720 | registers_changed (); | |
10d6c8cd DJ |
2721 | linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)), |
2722 | lp->step, signo); | |
d6b0e80f AC |
2723 | if (debug_linux_nat) |
2724 | fprintf_unfiltered (gdb_stdlog, | |
2725 | "LLW: %s %s, %s (preempt 'handle')\n", | |
2726 | lp->step ? | |
2727 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
2728 | target_pid_to_str (lp->ptid), | |
2729 | signo ? strsignal (signo) : "0"); | |
2730 | lp->stopped = 0; | |
2731 | status = 0; | |
2732 | goto retry; | |
2733 | } | |
2734 | ||
2735 | if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0) | |
2736 | { | |
2737 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
2738 | forwarded to the entire process group, that is, all LWP's | |
2739 | will receive it. Since we only want to report it once, | |
2740 | we try to flush it from all LWPs except this one. */ | |
2741 | sigaddset (&flush_mask, SIGINT); | |
2742 | } | |
2743 | } | |
2744 | ||
2745 | /* This LWP is stopped now. */ | |
2746 | lp->stopped = 1; | |
2747 | ||
2748 | if (debug_linux_nat) | |
2749 | fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n", | |
2750 | status_to_str (status), target_pid_to_str (lp->ptid)); | |
2751 | ||
2752 | /* Now stop all other LWP's ... */ | |
2753 | iterate_over_lwps (stop_callback, NULL); | |
2754 | ||
2755 | /* ... and wait until all of them have reported back that they're no | |
2756 | longer running. */ | |
2757 | iterate_over_lwps (stop_wait_callback, &flush_mask); | |
2758 | iterate_over_lwps (flush_callback, &flush_mask); | |
2759 | ||
2760 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
2761 | among those that have had events. Giving equal priority to all | |
2762 | LWPs that have had events helps prevent starvation. */ | |
2763 | if (pid == -1) | |
2764 | select_event_lwp (&lp, &status); | |
2765 | ||
2766 | /* Now that we've selected our final event LWP, cancel any | |
2767 | breakpoints in other LWPs that have hit a GDB breakpoint. See | |
2768 | the comment in cancel_breakpoints_callback to find out why. */ | |
2769 | iterate_over_lwps (cancel_breakpoints_callback, lp); | |
2770 | ||
d6b0e80f AC |
2771 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP) |
2772 | { | |
d6b0e80f AC |
2773 | if (debug_linux_nat) |
2774 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 PA |
2775 | "LLW: trap ptid is %s.\n", |
2776 | target_pid_to_str (lp->ptid)); | |
d6b0e80f | 2777 | } |
d6b0e80f AC |
2778 | |
2779 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
2780 | { | |
2781 | *ourstatus = lp->waitstatus; | |
2782 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
2783 | } | |
2784 | else | |
2785 | store_waitstatus (ourstatus, status); | |
2786 | ||
b84876c2 PA |
2787 | /* Get ready for the next event. */ |
2788 | if (target_can_async_p ()) | |
2789 | target_async (inferior_event_handler, 0); | |
2790 | ||
2791 | if (debug_linux_nat_async) | |
2792 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); | |
2793 | ||
f973ed9c | 2794 | return lp->ptid; |
d6b0e80f AC |
2795 | } |
2796 | ||
2797 | static int | |
2798 | kill_callback (struct lwp_info *lp, void *data) | |
2799 | { | |
2800 | errno = 0; | |
2801 | ptrace (PTRACE_KILL, GET_LWP (lp->ptid), 0, 0); | |
2802 | if (debug_linux_nat) | |
2803 | fprintf_unfiltered (gdb_stdlog, | |
2804 | "KC: PTRACE_KILL %s, 0, 0 (%s)\n", | |
2805 | target_pid_to_str (lp->ptid), | |
2806 | errno ? safe_strerror (errno) : "OK"); | |
2807 | ||
2808 | return 0; | |
2809 | } | |
2810 | ||
2811 | static int | |
2812 | kill_wait_callback (struct lwp_info *lp, void *data) | |
2813 | { | |
2814 | pid_t pid; | |
2815 | ||
2816 | /* We must make sure that there are no pending events (delayed | |
2817 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
2818 | program doesn't interfere with any following debugging session. */ | |
2819 | ||
2820 | /* For cloned processes we must check both with __WCLONE and | |
2821 | without, since the exit status of a cloned process isn't reported | |
2822 | with __WCLONE. */ | |
2823 | if (lp->cloned) | |
2824 | { | |
2825 | do | |
2826 | { | |
58aecb61 | 2827 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE); |
e85a822c | 2828 | if (pid != (pid_t) -1) |
d6b0e80f | 2829 | { |
e85a822c DJ |
2830 | if (debug_linux_nat) |
2831 | fprintf_unfiltered (gdb_stdlog, | |
2832 | "KWC: wait %s received unknown.\n", | |
2833 | target_pid_to_str (lp->ptid)); | |
2834 | /* The Linux kernel sometimes fails to kill a thread | |
2835 | completely after PTRACE_KILL; that goes from the stop | |
2836 | point in do_fork out to the one in | |
2837 | get_signal_to_deliever and waits again. So kill it | |
2838 | again. */ | |
2839 | kill_callback (lp, NULL); | |
d6b0e80f AC |
2840 | } |
2841 | } | |
2842 | while (pid == GET_LWP (lp->ptid)); | |
2843 | ||
2844 | gdb_assert (pid == -1 && errno == ECHILD); | |
2845 | } | |
2846 | ||
2847 | do | |
2848 | { | |
58aecb61 | 2849 | pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0); |
e85a822c | 2850 | if (pid != (pid_t) -1) |
d6b0e80f | 2851 | { |
e85a822c DJ |
2852 | if (debug_linux_nat) |
2853 | fprintf_unfiltered (gdb_stdlog, | |
2854 | "KWC: wait %s received unk.\n", | |
2855 | target_pid_to_str (lp->ptid)); | |
2856 | /* See the call to kill_callback above. */ | |
2857 | kill_callback (lp, NULL); | |
d6b0e80f AC |
2858 | } |
2859 | } | |
2860 | while (pid == GET_LWP (lp->ptid)); | |
2861 | ||
2862 | gdb_assert (pid == -1 && errno == ECHILD); | |
2863 | return 0; | |
2864 | } | |
2865 | ||
2866 | static void | |
2867 | linux_nat_kill (void) | |
2868 | { | |
f973ed9c DJ |
2869 | struct target_waitstatus last; |
2870 | ptid_t last_ptid; | |
2871 | int status; | |
d6b0e80f | 2872 | |
b84876c2 PA |
2873 | if (target_can_async_p ()) |
2874 | target_async (NULL, 0); | |
2875 | ||
f973ed9c DJ |
2876 | /* If we're stopped while forking and we haven't followed yet, |
2877 | kill the other task. We need to do this first because the | |
2878 | parent will be sleeping if this is a vfork. */ | |
d6b0e80f | 2879 | |
f973ed9c | 2880 | get_last_target_status (&last_ptid, &last); |
d6b0e80f | 2881 | |
f973ed9c DJ |
2882 | if (last.kind == TARGET_WAITKIND_FORKED |
2883 | || last.kind == TARGET_WAITKIND_VFORKED) | |
2884 | { | |
2885 | ptrace (PT_KILL, last.value.related_pid, 0, 0); | |
2886 | wait (&status); | |
2887 | } | |
2888 | ||
2889 | if (forks_exist_p ()) | |
b84876c2 PA |
2890 | { |
2891 | linux_fork_killall (); | |
2892 | drain_queued_events (-1); | |
2893 | } | |
f973ed9c DJ |
2894 | else |
2895 | { | |
2896 | /* Kill all LWP's ... */ | |
2897 | iterate_over_lwps (kill_callback, NULL); | |
2898 | ||
2899 | /* ... and wait until we've flushed all events. */ | |
2900 | iterate_over_lwps (kill_wait_callback, NULL); | |
2901 | } | |
2902 | ||
2903 | target_mourn_inferior (); | |
d6b0e80f AC |
2904 | } |
2905 | ||
2906 | static void | |
2907 | linux_nat_mourn_inferior (void) | |
2908 | { | |
d6b0e80f AC |
2909 | /* Destroy LWP info; it's no longer valid. */ |
2910 | init_lwp_list (); | |
2911 | ||
f973ed9c | 2912 | if (! forks_exist_p ()) |
b84876c2 PA |
2913 | { |
2914 | /* Normal case, no other forks available. */ | |
2915 | if (target_can_async_p ()) | |
2916 | linux_nat_async (NULL, 0); | |
2917 | linux_ops->to_mourn_inferior (); | |
2918 | } | |
f973ed9c DJ |
2919 | else |
2920 | /* Multi-fork case. The current inferior_ptid has exited, but | |
2921 | there are other viable forks to debug. Delete the exiting | |
2922 | one and context-switch to the first available. */ | |
2923 | linux_fork_mourn_inferior (); | |
d6b0e80f AC |
2924 | } |
2925 | ||
10d6c8cd DJ |
2926 | static LONGEST |
2927 | linux_nat_xfer_partial (struct target_ops *ops, enum target_object object, | |
2928 | const char *annex, gdb_byte *readbuf, | |
2929 | const gdb_byte *writebuf, | |
2930 | ULONGEST offset, LONGEST len) | |
d6b0e80f AC |
2931 | { |
2932 | struct cleanup *old_chain = save_inferior_ptid (); | |
10d6c8cd | 2933 | LONGEST xfer; |
d6b0e80f AC |
2934 | |
2935 | if (is_lwp (inferior_ptid)) | |
2936 | inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid)); | |
2937 | ||
10d6c8cd DJ |
2938 | xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf, |
2939 | offset, len); | |
d6b0e80f AC |
2940 | |
2941 | do_cleanups (old_chain); | |
2942 | return xfer; | |
2943 | } | |
2944 | ||
2945 | static int | |
2946 | linux_nat_thread_alive (ptid_t ptid) | |
2947 | { | |
2948 | gdb_assert (is_lwp (ptid)); | |
2949 | ||
2950 | errno = 0; | |
2951 | ptrace (PTRACE_PEEKUSER, GET_LWP (ptid), 0, 0); | |
2952 | if (debug_linux_nat) | |
2953 | fprintf_unfiltered (gdb_stdlog, | |
2954 | "LLTA: PTRACE_PEEKUSER %s, 0, 0 (%s)\n", | |
2955 | target_pid_to_str (ptid), | |
2956 | errno ? safe_strerror (errno) : "OK"); | |
9c0dd46b | 2957 | |
155bd5d1 AC |
2958 | /* Not every Linux kernel implements PTRACE_PEEKUSER. But we can |
2959 | handle that case gracefully since ptrace will first do a lookup | |
2960 | for the process based upon the passed-in pid. If that fails we | |
2961 | will get either -ESRCH or -EPERM, otherwise the child exists and | |
2962 | is alive. */ | |
a529be7c | 2963 | if (errno == ESRCH || errno == EPERM) |
d6b0e80f AC |
2964 | return 0; |
2965 | ||
2966 | return 1; | |
2967 | } | |
2968 | ||
2969 | static char * | |
2970 | linux_nat_pid_to_str (ptid_t ptid) | |
2971 | { | |
2972 | static char buf[64]; | |
2973 | ||
a0ef4274 DJ |
2974 | if (is_lwp (ptid) |
2975 | && ((lwp_list && lwp_list->next) | |
2976 | || GET_PID (ptid) != GET_LWP (ptid))) | |
d6b0e80f AC |
2977 | { |
2978 | snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid)); | |
2979 | return buf; | |
2980 | } | |
2981 | ||
2982 | return normal_pid_to_str (ptid); | |
2983 | } | |
2984 | ||
d6b0e80f AC |
2985 | static void |
2986 | sigchld_handler (int signo) | |
2987 | { | |
b84876c2 PA |
2988 | if (linux_nat_async_enabled |
2989 | && linux_nat_async_events_enabled | |
2990 | && signo == SIGCHLD) | |
2991 | /* It is *always* a bug to hit this. */ | |
2992 | internal_error (__FILE__, __LINE__, | |
2993 | "sigchld_handler called when async events are enabled"); | |
2994 | ||
d6b0e80f AC |
2995 | /* Do nothing. The only reason for this handler is that it allows |
2996 | us to use sigsuspend in linux_nat_wait above to wait for the | |
2997 | arrival of a SIGCHLD. */ | |
2998 | } | |
2999 | ||
dba24537 AC |
3000 | /* Accepts an integer PID; Returns a string representing a file that |
3001 | can be opened to get the symbols for the child process. */ | |
3002 | ||
6d8fd2b7 UW |
3003 | static char * |
3004 | linux_child_pid_to_exec_file (int pid) | |
dba24537 AC |
3005 | { |
3006 | char *name1, *name2; | |
3007 | ||
3008 | name1 = xmalloc (MAXPATHLEN); | |
3009 | name2 = xmalloc (MAXPATHLEN); | |
3010 | make_cleanup (xfree, name1); | |
3011 | make_cleanup (xfree, name2); | |
3012 | memset (name2, 0, MAXPATHLEN); | |
3013 | ||
3014 | sprintf (name1, "/proc/%d/exe", pid); | |
3015 | if (readlink (name1, name2, MAXPATHLEN) > 0) | |
3016 | return name2; | |
3017 | else | |
3018 | return name1; | |
3019 | } | |
3020 | ||
3021 | /* Service function for corefiles and info proc. */ | |
3022 | ||
3023 | static int | |
3024 | read_mapping (FILE *mapfile, | |
3025 | long long *addr, | |
3026 | long long *endaddr, | |
3027 | char *permissions, | |
3028 | long long *offset, | |
3029 | char *device, long long *inode, char *filename) | |
3030 | { | |
3031 | int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx", | |
3032 | addr, endaddr, permissions, offset, device, inode); | |
3033 | ||
2e14c2ea MS |
3034 | filename[0] = '\0'; |
3035 | if (ret > 0 && ret != EOF) | |
dba24537 AC |
3036 | { |
3037 | /* Eat everything up to EOL for the filename. This will prevent | |
3038 | weird filenames (such as one with embedded whitespace) from | |
3039 | confusing this code. It also makes this code more robust in | |
3040 | respect to annotations the kernel may add after the filename. | |
3041 | ||
3042 | Note the filename is used for informational purposes | |
3043 | only. */ | |
3044 | ret += fscanf (mapfile, "%[^\n]\n", filename); | |
3045 | } | |
2e14c2ea | 3046 | |
dba24537 AC |
3047 | return (ret != 0 && ret != EOF); |
3048 | } | |
3049 | ||
3050 | /* Fills the "to_find_memory_regions" target vector. Lists the memory | |
3051 | regions in the inferior for a corefile. */ | |
3052 | ||
3053 | static int | |
3054 | linux_nat_find_memory_regions (int (*func) (CORE_ADDR, | |
3055 | unsigned long, | |
3056 | int, int, int, void *), void *obfd) | |
3057 | { | |
3058 | long long pid = PIDGET (inferior_ptid); | |
3059 | char mapsfilename[MAXPATHLEN]; | |
3060 | FILE *mapsfile; | |
3061 | long long addr, endaddr, size, offset, inode; | |
3062 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3063 | int read, write, exec; | |
3064 | int ret; | |
3065 | ||
3066 | /* Compose the filename for the /proc memory map, and open it. */ | |
3067 | sprintf (mapsfilename, "/proc/%lld/maps", pid); | |
3068 | if ((mapsfile = fopen (mapsfilename, "r")) == NULL) | |
8a3fe4f8 | 3069 | error (_("Could not open %s."), mapsfilename); |
dba24537 AC |
3070 | |
3071 | if (info_verbose) | |
3072 | fprintf_filtered (gdb_stdout, | |
3073 | "Reading memory regions from %s\n", mapsfilename); | |
3074 | ||
3075 | /* Now iterate until end-of-file. */ | |
3076 | while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0], | |
3077 | &offset, &device[0], &inode, &filename[0])) | |
3078 | { | |
3079 | size = endaddr - addr; | |
3080 | ||
3081 | /* Get the segment's permissions. */ | |
3082 | read = (strchr (permissions, 'r') != 0); | |
3083 | write = (strchr (permissions, 'w') != 0); | |
3084 | exec = (strchr (permissions, 'x') != 0); | |
3085 | ||
3086 | if (info_verbose) | |
3087 | { | |
3088 | fprintf_filtered (gdb_stdout, | |
3089 | "Save segment, %lld bytes at 0x%s (%c%c%c)", | |
3090 | size, paddr_nz (addr), | |
3091 | read ? 'r' : ' ', | |
3092 | write ? 'w' : ' ', exec ? 'x' : ' '); | |
b260b6c1 | 3093 | if (filename[0]) |
dba24537 AC |
3094 | fprintf_filtered (gdb_stdout, " for %s", filename); |
3095 | fprintf_filtered (gdb_stdout, "\n"); | |
3096 | } | |
3097 | ||
3098 | /* Invoke the callback function to create the corefile | |
3099 | segment. */ | |
3100 | func (addr, size, read, write, exec, obfd); | |
3101 | } | |
3102 | fclose (mapsfile); | |
3103 | return 0; | |
3104 | } | |
3105 | ||
3106 | /* Records the thread's register state for the corefile note | |
3107 | section. */ | |
3108 | ||
3109 | static char * | |
3110 | linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid, | |
3111 | char *note_data, int *note_size) | |
3112 | { | |
3113 | gdb_gregset_t gregs; | |
3114 | gdb_fpregset_t fpregs; | |
dba24537 | 3115 | unsigned long lwp = ptid_get_lwp (ptid); |
594f7785 UW |
3116 | struct regcache *regcache = get_thread_regcache (ptid); |
3117 | struct gdbarch *gdbarch = get_regcache_arch (regcache); | |
4f844a66 | 3118 | const struct regset *regset; |
55e969c1 | 3119 | int core_regset_p; |
594f7785 | 3120 | struct cleanup *old_chain; |
17ea7499 CES |
3121 | struct core_regset_section *sect_list; |
3122 | char *gdb_regset; | |
594f7785 UW |
3123 | |
3124 | old_chain = save_inferior_ptid (); | |
3125 | inferior_ptid = ptid; | |
3126 | target_fetch_registers (regcache, -1); | |
3127 | do_cleanups (old_chain); | |
4f844a66 DM |
3128 | |
3129 | core_regset_p = gdbarch_regset_from_core_section_p (gdbarch); | |
17ea7499 CES |
3130 | sect_list = gdbarch_core_regset_sections (gdbarch); |
3131 | ||
55e969c1 DM |
3132 | if (core_regset_p |
3133 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg", | |
3134 | sizeof (gregs))) != NULL | |
3135 | && regset->collect_regset != NULL) | |
594f7785 | 3136 | regset->collect_regset (regset, regcache, -1, |
55e969c1 | 3137 | &gregs, sizeof (gregs)); |
4f844a66 | 3138 | else |
594f7785 | 3139 | fill_gregset (regcache, &gregs, -1); |
4f844a66 | 3140 | |
55e969c1 DM |
3141 | note_data = (char *) elfcore_write_prstatus (obfd, |
3142 | note_data, | |
3143 | note_size, | |
3144 | lwp, | |
3145 | stop_signal, &gregs); | |
3146 | ||
17ea7499 CES |
3147 | /* The loop below uses the new struct core_regset_section, which stores |
3148 | the supported section names and sizes for the core file. Note that | |
3149 | note PRSTATUS needs to be treated specially. But the other notes are | |
3150 | structurally the same, so they can benefit from the new struct. */ | |
3151 | if (core_regset_p && sect_list != NULL) | |
3152 | while (sect_list->sect_name != NULL) | |
3153 | { | |
3154 | /* .reg was already handled above. */ | |
3155 | if (strcmp (sect_list->sect_name, ".reg") == 0) | |
3156 | { | |
3157 | sect_list++; | |
3158 | continue; | |
3159 | } | |
3160 | regset = gdbarch_regset_from_core_section (gdbarch, | |
3161 | sect_list->sect_name, | |
3162 | sect_list->size); | |
3163 | gdb_assert (regset && regset->collect_regset); | |
3164 | gdb_regset = xmalloc (sect_list->size); | |
3165 | regset->collect_regset (regset, regcache, -1, | |
3166 | gdb_regset, sect_list->size); | |
3167 | note_data = (char *) elfcore_write_register_note (obfd, | |
3168 | note_data, | |
3169 | note_size, | |
3170 | sect_list->sect_name, | |
3171 | gdb_regset, | |
3172 | sect_list->size); | |
3173 | xfree (gdb_regset); | |
3174 | sect_list++; | |
3175 | } | |
dba24537 | 3176 | |
17ea7499 CES |
3177 | /* For architectures that does not have the struct core_regset_section |
3178 | implemented, we use the old method. When all the architectures have | |
3179 | the new support, the code below should be deleted. */ | |
4f844a66 | 3180 | else |
17ea7499 CES |
3181 | { |
3182 | if (core_regset_p | |
3183 | && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", | |
3184 | sizeof (fpregs))) != NULL | |
3185 | && regset->collect_regset != NULL) | |
3186 | regset->collect_regset (regset, regcache, -1, | |
3187 | &fpregs, sizeof (fpregs)); | |
3188 | else | |
3189 | fill_fpregset (regcache, &fpregs, -1); | |
3190 | ||
3191 | note_data = (char *) elfcore_write_prfpreg (obfd, | |
3192 | note_data, | |
3193 | note_size, | |
3194 | &fpregs, sizeof (fpregs)); | |
3195 | } | |
4f844a66 | 3196 | |
dba24537 AC |
3197 | return note_data; |
3198 | } | |
3199 | ||
3200 | struct linux_nat_corefile_thread_data | |
3201 | { | |
3202 | bfd *obfd; | |
3203 | char *note_data; | |
3204 | int *note_size; | |
3205 | int num_notes; | |
3206 | }; | |
3207 | ||
3208 | /* Called by gdbthread.c once per thread. Records the thread's | |
3209 | register state for the corefile note section. */ | |
3210 | ||
3211 | static int | |
3212 | linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data) | |
3213 | { | |
3214 | struct linux_nat_corefile_thread_data *args = data; | |
dba24537 | 3215 | |
dba24537 AC |
3216 | args->note_data = linux_nat_do_thread_registers (args->obfd, |
3217 | ti->ptid, | |
3218 | args->note_data, | |
3219 | args->note_size); | |
3220 | args->num_notes++; | |
56be3814 | 3221 | |
dba24537 AC |
3222 | return 0; |
3223 | } | |
3224 | ||
3225 | /* Records the register state for the corefile note section. */ | |
3226 | ||
3227 | static char * | |
3228 | linux_nat_do_registers (bfd *obfd, ptid_t ptid, | |
3229 | char *note_data, int *note_size) | |
3230 | { | |
dba24537 AC |
3231 | return linux_nat_do_thread_registers (obfd, |
3232 | ptid_build (ptid_get_pid (inferior_ptid), | |
3233 | ptid_get_pid (inferior_ptid), | |
3234 | 0), | |
3235 | note_data, note_size); | |
dba24537 AC |
3236 | } |
3237 | ||
3238 | /* Fills the "to_make_corefile_note" target vector. Builds the note | |
3239 | section for a corefile, and returns it in a malloc buffer. */ | |
3240 | ||
3241 | static char * | |
3242 | linux_nat_make_corefile_notes (bfd *obfd, int *note_size) | |
3243 | { | |
3244 | struct linux_nat_corefile_thread_data thread_args; | |
3245 | struct cleanup *old_chain; | |
d99148ef | 3246 | /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */ |
dba24537 | 3247 | char fname[16] = { '\0' }; |
d99148ef | 3248 | /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */ |
dba24537 AC |
3249 | char psargs[80] = { '\0' }; |
3250 | char *note_data = NULL; | |
3251 | ptid_t current_ptid = inferior_ptid; | |
c6826062 | 3252 | gdb_byte *auxv; |
dba24537 AC |
3253 | int auxv_len; |
3254 | ||
3255 | if (get_exec_file (0)) | |
3256 | { | |
3257 | strncpy (fname, strrchr (get_exec_file (0), '/') + 1, sizeof (fname)); | |
3258 | strncpy (psargs, get_exec_file (0), sizeof (psargs)); | |
3259 | if (get_inferior_args ()) | |
3260 | { | |
d99148ef JK |
3261 | char *string_end; |
3262 | char *psargs_end = psargs + sizeof (psargs); | |
3263 | ||
3264 | /* linux_elfcore_write_prpsinfo () handles zero unterminated | |
3265 | strings fine. */ | |
3266 | string_end = memchr (psargs, 0, sizeof (psargs)); | |
3267 | if (string_end != NULL) | |
3268 | { | |
3269 | *string_end++ = ' '; | |
3270 | strncpy (string_end, get_inferior_args (), | |
3271 | psargs_end - string_end); | |
3272 | } | |
dba24537 AC |
3273 | } |
3274 | note_data = (char *) elfcore_write_prpsinfo (obfd, | |
3275 | note_data, | |
3276 | note_size, fname, psargs); | |
3277 | } | |
3278 | ||
3279 | /* Dump information for threads. */ | |
3280 | thread_args.obfd = obfd; | |
3281 | thread_args.note_data = note_data; | |
3282 | thread_args.note_size = note_size; | |
3283 | thread_args.num_notes = 0; | |
3284 | iterate_over_lwps (linux_nat_corefile_thread_callback, &thread_args); | |
3285 | if (thread_args.num_notes == 0) | |
3286 | { | |
3287 | /* iterate_over_threads didn't come up with any threads; just | |
3288 | use inferior_ptid. */ | |
3289 | note_data = linux_nat_do_registers (obfd, inferior_ptid, | |
3290 | note_data, note_size); | |
3291 | } | |
3292 | else | |
3293 | { | |
3294 | note_data = thread_args.note_data; | |
3295 | } | |
3296 | ||
13547ab6 DJ |
3297 | auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV, |
3298 | NULL, &auxv); | |
dba24537 AC |
3299 | if (auxv_len > 0) |
3300 | { | |
3301 | note_data = elfcore_write_note (obfd, note_data, note_size, | |
3302 | "CORE", NT_AUXV, auxv, auxv_len); | |
3303 | xfree (auxv); | |
3304 | } | |
3305 | ||
3306 | make_cleanup (xfree, note_data); | |
3307 | return note_data; | |
3308 | } | |
3309 | ||
3310 | /* Implement the "info proc" command. */ | |
3311 | ||
3312 | static void | |
3313 | linux_nat_info_proc_cmd (char *args, int from_tty) | |
3314 | { | |
3315 | long long pid = PIDGET (inferior_ptid); | |
3316 | FILE *procfile; | |
3317 | char **argv = NULL; | |
3318 | char buffer[MAXPATHLEN]; | |
3319 | char fname1[MAXPATHLEN], fname2[MAXPATHLEN]; | |
3320 | int cmdline_f = 1; | |
3321 | int cwd_f = 1; | |
3322 | int exe_f = 1; | |
3323 | int mappings_f = 0; | |
3324 | int environ_f = 0; | |
3325 | int status_f = 0; | |
3326 | int stat_f = 0; | |
3327 | int all = 0; | |
3328 | struct stat dummy; | |
3329 | ||
3330 | if (args) | |
3331 | { | |
3332 | /* Break up 'args' into an argv array. */ | |
3333 | if ((argv = buildargv (args)) == NULL) | |
3334 | nomem (0); | |
3335 | else | |
3336 | make_cleanup_freeargv (argv); | |
3337 | } | |
3338 | while (argv != NULL && *argv != NULL) | |
3339 | { | |
3340 | if (isdigit (argv[0][0])) | |
3341 | { | |
3342 | pid = strtoul (argv[0], NULL, 10); | |
3343 | } | |
3344 | else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0) | |
3345 | { | |
3346 | mappings_f = 1; | |
3347 | } | |
3348 | else if (strcmp (argv[0], "status") == 0) | |
3349 | { | |
3350 | status_f = 1; | |
3351 | } | |
3352 | else if (strcmp (argv[0], "stat") == 0) | |
3353 | { | |
3354 | stat_f = 1; | |
3355 | } | |
3356 | else if (strcmp (argv[0], "cmd") == 0) | |
3357 | { | |
3358 | cmdline_f = 1; | |
3359 | } | |
3360 | else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0) | |
3361 | { | |
3362 | exe_f = 1; | |
3363 | } | |
3364 | else if (strcmp (argv[0], "cwd") == 0) | |
3365 | { | |
3366 | cwd_f = 1; | |
3367 | } | |
3368 | else if (strncmp (argv[0], "all", strlen (argv[0])) == 0) | |
3369 | { | |
3370 | all = 1; | |
3371 | } | |
3372 | else | |
3373 | { | |
3374 | /* [...] (future options here) */ | |
3375 | } | |
3376 | argv++; | |
3377 | } | |
3378 | if (pid == 0) | |
8a3fe4f8 | 3379 | error (_("No current process: you must name one.")); |
dba24537 AC |
3380 | |
3381 | sprintf (fname1, "/proc/%lld", pid); | |
3382 | if (stat (fname1, &dummy) != 0) | |
8a3fe4f8 | 3383 | error (_("No /proc directory: '%s'"), fname1); |
dba24537 | 3384 | |
a3f17187 | 3385 | printf_filtered (_("process %lld\n"), pid); |
dba24537 AC |
3386 | if (cmdline_f || all) |
3387 | { | |
3388 | sprintf (fname1, "/proc/%lld/cmdline", pid); | |
d5d6fca5 | 3389 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3390 | { |
3391 | fgets (buffer, sizeof (buffer), procfile); | |
3392 | printf_filtered ("cmdline = '%s'\n", buffer); | |
3393 | fclose (procfile); | |
3394 | } | |
3395 | else | |
8a3fe4f8 | 3396 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3397 | } |
3398 | if (cwd_f || all) | |
3399 | { | |
3400 | sprintf (fname1, "/proc/%lld/cwd", pid); | |
3401 | memset (fname2, 0, sizeof (fname2)); | |
3402 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3403 | printf_filtered ("cwd = '%s'\n", fname2); | |
3404 | else | |
8a3fe4f8 | 3405 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3406 | } |
3407 | if (exe_f || all) | |
3408 | { | |
3409 | sprintf (fname1, "/proc/%lld/exe", pid); | |
3410 | memset (fname2, 0, sizeof (fname2)); | |
3411 | if (readlink (fname1, fname2, sizeof (fname2)) > 0) | |
3412 | printf_filtered ("exe = '%s'\n", fname2); | |
3413 | else | |
8a3fe4f8 | 3414 | warning (_("unable to read link '%s'"), fname1); |
dba24537 AC |
3415 | } |
3416 | if (mappings_f || all) | |
3417 | { | |
3418 | sprintf (fname1, "/proc/%lld/maps", pid); | |
d5d6fca5 | 3419 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3420 | { |
3421 | long long addr, endaddr, size, offset, inode; | |
3422 | char permissions[8], device[8], filename[MAXPATHLEN]; | |
3423 | ||
a3f17187 | 3424 | printf_filtered (_("Mapped address spaces:\n\n")); |
17a912b6 | 3425 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3426 | { |
3427 | printf_filtered ("\t%10s %10s %10s %10s %7s\n", | |
3428 | "Start Addr", | |
3429 | " End Addr", | |
3430 | " Size", " Offset", "objfile"); | |
3431 | } | |
3432 | else | |
3433 | { | |
3434 | printf_filtered (" %18s %18s %10s %10s %7s\n", | |
3435 | "Start Addr", | |
3436 | " End Addr", | |
3437 | " Size", " Offset", "objfile"); | |
3438 | } | |
3439 | ||
3440 | while (read_mapping (procfile, &addr, &endaddr, &permissions[0], | |
3441 | &offset, &device[0], &inode, &filename[0])) | |
3442 | { | |
3443 | size = endaddr - addr; | |
3444 | ||
3445 | /* FIXME: carlton/2003-08-27: Maybe the printf_filtered | |
3446 | calls here (and possibly above) should be abstracted | |
3447 | out into their own functions? Andrew suggests using | |
3448 | a generic local_address_string instead to print out | |
3449 | the addresses; that makes sense to me, too. */ | |
3450 | ||
17a912b6 | 3451 | if (gdbarch_addr_bit (current_gdbarch) == 32) |
dba24537 AC |
3452 | { |
3453 | printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n", | |
3454 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3455 | (unsigned long) endaddr, | |
3456 | (int) size, | |
3457 | (unsigned int) offset, | |
3458 | filename[0] ? filename : ""); | |
3459 | } | |
3460 | else | |
3461 | { | |
3462 | printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n", | |
3463 | (unsigned long) addr, /* FIXME: pr_addr */ | |
3464 | (unsigned long) endaddr, | |
3465 | (int) size, | |
3466 | (unsigned int) offset, | |
3467 | filename[0] ? filename : ""); | |
3468 | } | |
3469 | } | |
3470 | ||
3471 | fclose (procfile); | |
3472 | } | |
3473 | else | |
8a3fe4f8 | 3474 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3475 | } |
3476 | if (status_f || all) | |
3477 | { | |
3478 | sprintf (fname1, "/proc/%lld/status", pid); | |
d5d6fca5 | 3479 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3480 | { |
3481 | while (fgets (buffer, sizeof (buffer), procfile) != NULL) | |
3482 | puts_filtered (buffer); | |
3483 | fclose (procfile); | |
3484 | } | |
3485 | else | |
8a3fe4f8 | 3486 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3487 | } |
3488 | if (stat_f || all) | |
3489 | { | |
3490 | sprintf (fname1, "/proc/%lld/stat", pid); | |
d5d6fca5 | 3491 | if ((procfile = fopen (fname1, "r")) != NULL) |
dba24537 AC |
3492 | { |
3493 | int itmp; | |
3494 | char ctmp; | |
a25694b4 | 3495 | long ltmp; |
dba24537 AC |
3496 | |
3497 | if (fscanf (procfile, "%d ", &itmp) > 0) | |
a3f17187 | 3498 | printf_filtered (_("Process: %d\n"), itmp); |
a25694b4 | 3499 | if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0) |
a3f17187 | 3500 | printf_filtered (_("Exec file: %s\n"), buffer); |
dba24537 | 3501 | if (fscanf (procfile, "%c ", &ctmp) > 0) |
a3f17187 | 3502 | printf_filtered (_("State: %c\n"), ctmp); |
dba24537 | 3503 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3504 | printf_filtered (_("Parent process: %d\n"), itmp); |
dba24537 | 3505 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3506 | printf_filtered (_("Process group: %d\n"), itmp); |
dba24537 | 3507 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3508 | printf_filtered (_("Session id: %d\n"), itmp); |
dba24537 | 3509 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3510 | printf_filtered (_("TTY: %d\n"), itmp); |
dba24537 | 3511 | if (fscanf (procfile, "%d ", &itmp) > 0) |
a3f17187 | 3512 | printf_filtered (_("TTY owner process group: %d\n"), itmp); |
a25694b4 AS |
3513 | if (fscanf (procfile, "%lu ", <mp) > 0) |
3514 | printf_filtered (_("Flags: 0x%lx\n"), ltmp); | |
3515 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3516 | printf_filtered (_("Minor faults (no memory page): %lu\n"), | |
3517 | (unsigned long) ltmp); | |
3518 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3519 | printf_filtered (_("Minor faults, children: %lu\n"), | |
3520 | (unsigned long) ltmp); | |
3521 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3522 | printf_filtered (_("Major faults (memory page faults): %lu\n"), | |
3523 | (unsigned long) ltmp); | |
3524 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3525 | printf_filtered (_("Major faults, children: %lu\n"), | |
3526 | (unsigned long) ltmp); | |
3527 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3528 | printf_filtered (_("utime: %ld\n"), ltmp); | |
3529 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3530 | printf_filtered (_("stime: %ld\n"), ltmp); | |
3531 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3532 | printf_filtered (_("utime, children: %ld\n"), ltmp); | |
3533 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3534 | printf_filtered (_("stime, children: %ld\n"), ltmp); | |
3535 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3536 | printf_filtered (_("jiffies remaining in current time slice: %ld\n"), | |
3537 | ltmp); | |
3538 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3539 | printf_filtered (_("'nice' value: %ld\n"), ltmp); | |
3540 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3541 | printf_filtered (_("jiffies until next timeout: %lu\n"), | |
3542 | (unsigned long) ltmp); | |
3543 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3544 | printf_filtered (_("jiffies until next SIGALRM: %lu\n"), | |
3545 | (unsigned long) ltmp); | |
3546 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3547 | printf_filtered (_("start time (jiffies since system boot): %ld\n"), | |
3548 | ltmp); | |
3549 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3550 | printf_filtered (_("Virtual memory size: %lu\n"), | |
3551 | (unsigned long) ltmp); | |
3552 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3553 | printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp); | |
3554 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3555 | printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp); | |
3556 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3557 | printf_filtered (_("Start of text: 0x%lx\n"), ltmp); | |
3558 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3559 | printf_filtered (_("End of text: 0x%lx\n"), ltmp); | |
3560 | if (fscanf (procfile, "%lu ", <mp) > 0) | |
3561 | printf_filtered (_("Start of stack: 0x%lx\n"), ltmp); | |
dba24537 AC |
3562 | #if 0 /* Don't know how architecture-dependent the rest is... |
3563 | Anyway the signal bitmap info is available from "status". */ | |
a25694b4 AS |
3564 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ |
3565 | printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp); | |
3566 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3567 | printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp); | |
3568 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3569 | printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp); | |
3570 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3571 | printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp); | |
3572 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3573 | printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp); | |
3574 | if (fscanf (procfile, "%ld ", <mp) > 0) | |
3575 | printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp); | |
3576 | if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ | |
3577 | printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp); | |
dba24537 AC |
3578 | #endif |
3579 | fclose (procfile); | |
3580 | } | |
3581 | else | |
8a3fe4f8 | 3582 | warning (_("unable to open /proc file '%s'"), fname1); |
dba24537 AC |
3583 | } |
3584 | } | |
3585 | ||
10d6c8cd DJ |
3586 | /* Implement the to_xfer_partial interface for memory reads using the /proc |
3587 | filesystem. Because we can use a single read() call for /proc, this | |
3588 | can be much more efficient than banging away at PTRACE_PEEKTEXT, | |
3589 | but it doesn't support writes. */ | |
3590 | ||
3591 | static LONGEST | |
3592 | linux_proc_xfer_partial (struct target_ops *ops, enum target_object object, | |
3593 | const char *annex, gdb_byte *readbuf, | |
3594 | const gdb_byte *writebuf, | |
3595 | ULONGEST offset, LONGEST len) | |
dba24537 | 3596 | { |
10d6c8cd DJ |
3597 | LONGEST ret; |
3598 | int fd; | |
dba24537 AC |
3599 | char filename[64]; |
3600 | ||
10d6c8cd | 3601 | if (object != TARGET_OBJECT_MEMORY || !readbuf) |
dba24537 AC |
3602 | return 0; |
3603 | ||
3604 | /* Don't bother for one word. */ | |
3605 | if (len < 3 * sizeof (long)) | |
3606 | return 0; | |
3607 | ||
3608 | /* We could keep this file open and cache it - possibly one per | |
3609 | thread. That requires some juggling, but is even faster. */ | |
3610 | sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid)); | |
3611 | fd = open (filename, O_RDONLY | O_LARGEFILE); | |
3612 | if (fd == -1) | |
3613 | return 0; | |
3614 | ||
3615 | /* If pread64 is available, use it. It's faster if the kernel | |
3616 | supports it (only one syscall), and it's 64-bit safe even on | |
3617 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
3618 | application). */ | |
3619 | #ifdef HAVE_PREAD64 | |
10d6c8cd | 3620 | if (pread64 (fd, readbuf, len, offset) != len) |
dba24537 | 3621 | #else |
10d6c8cd | 3622 | if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len) |
dba24537 AC |
3623 | #endif |
3624 | ret = 0; | |
3625 | else | |
3626 | ret = len; | |
3627 | ||
3628 | close (fd); | |
3629 | return ret; | |
3630 | } | |
3631 | ||
3632 | /* Parse LINE as a signal set and add its set bits to SIGS. */ | |
3633 | ||
3634 | static void | |
3635 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
3636 | { | |
3637 | int len = strlen (line) - 1; | |
3638 | const char *p; | |
3639 | int signum; | |
3640 | ||
3641 | if (line[len] != '\n') | |
8a3fe4f8 | 3642 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3643 | |
3644 | p = line; | |
3645 | signum = len * 4; | |
3646 | while (len-- > 0) | |
3647 | { | |
3648 | int digit; | |
3649 | ||
3650 | if (*p >= '0' && *p <= '9') | |
3651 | digit = *p - '0'; | |
3652 | else if (*p >= 'a' && *p <= 'f') | |
3653 | digit = *p - 'a' + 10; | |
3654 | else | |
8a3fe4f8 | 3655 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
3656 | |
3657 | signum -= 4; | |
3658 | ||
3659 | if (digit & 1) | |
3660 | sigaddset (sigs, signum + 1); | |
3661 | if (digit & 2) | |
3662 | sigaddset (sigs, signum + 2); | |
3663 | if (digit & 4) | |
3664 | sigaddset (sigs, signum + 3); | |
3665 | if (digit & 8) | |
3666 | sigaddset (sigs, signum + 4); | |
3667 | ||
3668 | p++; | |
3669 | } | |
3670 | } | |
3671 | ||
3672 | /* Find process PID's pending signals from /proc/pid/status and set | |
3673 | SIGS to match. */ | |
3674 | ||
3675 | void | |
3676 | linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigset_t *ignored) | |
3677 | { | |
3678 | FILE *procfile; | |
3679 | char buffer[MAXPATHLEN], fname[MAXPATHLEN]; | |
3680 | int signum; | |
3681 | ||
3682 | sigemptyset (pending); | |
3683 | sigemptyset (blocked); | |
3684 | sigemptyset (ignored); | |
3685 | sprintf (fname, "/proc/%d/status", pid); | |
3686 | procfile = fopen (fname, "r"); | |
3687 | if (procfile == NULL) | |
8a3fe4f8 | 3688 | error (_("Could not open %s"), fname); |
dba24537 AC |
3689 | |
3690 | while (fgets (buffer, MAXPATHLEN, procfile) != NULL) | |
3691 | { | |
3692 | /* Normal queued signals are on the SigPnd line in the status | |
3693 | file. However, 2.6 kernels also have a "shared" pending | |
3694 | queue for delivering signals to a thread group, so check for | |
3695 | a ShdPnd line also. | |
3696 | ||
3697 | Unfortunately some Red Hat kernels include the shared pending | |
3698 | queue but not the ShdPnd status field. */ | |
3699 | ||
3700 | if (strncmp (buffer, "SigPnd:\t", 8) == 0) | |
3701 | add_line_to_sigset (buffer + 8, pending); | |
3702 | else if (strncmp (buffer, "ShdPnd:\t", 8) == 0) | |
3703 | add_line_to_sigset (buffer + 8, pending); | |
3704 | else if (strncmp (buffer, "SigBlk:\t", 8) == 0) | |
3705 | add_line_to_sigset (buffer + 8, blocked); | |
3706 | else if (strncmp (buffer, "SigIgn:\t", 8) == 0) | |
3707 | add_line_to_sigset (buffer + 8, ignored); | |
3708 | } | |
3709 | ||
3710 | fclose (procfile); | |
3711 | } | |
3712 | ||
10d6c8cd DJ |
3713 | static LONGEST |
3714 | linux_xfer_partial (struct target_ops *ops, enum target_object object, | |
3715 | const char *annex, gdb_byte *readbuf, | |
3716 | const gdb_byte *writebuf, ULONGEST offset, LONGEST len) | |
3717 | { | |
3718 | LONGEST xfer; | |
3719 | ||
3720 | if (object == TARGET_OBJECT_AUXV) | |
3721 | return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf, | |
3722 | offset, len); | |
3723 | ||
3724 | xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3725 | offset, len); | |
3726 | if (xfer != 0) | |
3727 | return xfer; | |
3728 | ||
3729 | return super_xfer_partial (ops, object, annex, readbuf, writebuf, | |
3730 | offset, len); | |
3731 | } | |
3732 | ||
e9efe249 | 3733 | /* Create a prototype generic GNU/Linux target. The client can override |
10d6c8cd DJ |
3734 | it with local methods. */ |
3735 | ||
910122bf UW |
3736 | static void |
3737 | linux_target_install_ops (struct target_ops *t) | |
10d6c8cd | 3738 | { |
6d8fd2b7 UW |
3739 | t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint; |
3740 | t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint; | |
3741 | t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint; | |
3742 | t->to_pid_to_exec_file = linux_child_pid_to_exec_file; | |
10d6c8cd | 3743 | t->to_post_startup_inferior = linux_child_post_startup_inferior; |
6d8fd2b7 UW |
3744 | t->to_post_attach = linux_child_post_attach; |
3745 | t->to_follow_fork = linux_child_follow_fork; | |
10d6c8cd DJ |
3746 | t->to_find_memory_regions = linux_nat_find_memory_regions; |
3747 | t->to_make_corefile_notes = linux_nat_make_corefile_notes; | |
3748 | ||
3749 | super_xfer_partial = t->to_xfer_partial; | |
3750 | t->to_xfer_partial = linux_xfer_partial; | |
910122bf UW |
3751 | } |
3752 | ||
3753 | struct target_ops * | |
3754 | linux_target (void) | |
3755 | { | |
3756 | struct target_ops *t; | |
3757 | ||
3758 | t = inf_ptrace_target (); | |
3759 | linux_target_install_ops (t); | |
3760 | ||
3761 | return t; | |
3762 | } | |
3763 | ||
3764 | struct target_ops * | |
7714d83a | 3765 | linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int)) |
910122bf UW |
3766 | { |
3767 | struct target_ops *t; | |
3768 | ||
3769 | t = inf_ptrace_trad_target (register_u_offset); | |
3770 | linux_target_install_ops (t); | |
10d6c8cd | 3771 | |
10d6c8cd DJ |
3772 | return t; |
3773 | } | |
3774 | ||
b84876c2 PA |
3775 | /* Controls if async mode is permitted. */ |
3776 | static int linux_async_permitted = 0; | |
3777 | ||
3778 | /* The set command writes to this variable. If the inferior is | |
3779 | executing, linux_nat_async_permitted is *not* updated. */ | |
3780 | static int linux_async_permitted_1 = 0; | |
3781 | ||
3782 | static void | |
3783 | set_maintenance_linux_async_permitted (char *args, int from_tty, | |
3784 | struct cmd_list_element *c) | |
3785 | { | |
3786 | if (target_has_execution) | |
3787 | { | |
3788 | linux_async_permitted_1 = linux_async_permitted; | |
3789 | error (_("Cannot change this setting while the inferior is running.")); | |
3790 | } | |
3791 | ||
3792 | linux_async_permitted = linux_async_permitted_1; | |
3793 | linux_nat_set_async_mode (linux_async_permitted); | |
3794 | } | |
3795 | ||
3796 | static void | |
3797 | show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty, | |
3798 | struct cmd_list_element *c, const char *value) | |
3799 | { | |
3800 | fprintf_filtered (file, _("\ | |
3801 | Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"), | |
3802 | value); | |
3803 | } | |
3804 | ||
3805 | /* target_is_async_p implementation. */ | |
3806 | ||
3807 | static int | |
3808 | linux_nat_is_async_p (void) | |
3809 | { | |
3810 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
3811 | it explicitly with the "maintenance set linux-async" command. | |
3812 | Someday, linux will always be async. */ | |
3813 | if (!linux_async_permitted) | |
3814 | return 0; | |
3815 | ||
3816 | return 1; | |
3817 | } | |
3818 | ||
3819 | /* target_can_async_p implementation. */ | |
3820 | ||
3821 | static int | |
3822 | linux_nat_can_async_p (void) | |
3823 | { | |
3824 | /* NOTE: palves 2008-03-21: We're only async when the user requests | |
3825 | it explicitly with the "maintenance set linux-async" command. | |
3826 | Someday, linux will always be async. */ | |
3827 | if (!linux_async_permitted) | |
3828 | return 0; | |
3829 | ||
3830 | /* See target.h/target_async_mask. */ | |
3831 | return linux_nat_async_mask_value; | |
3832 | } | |
3833 | ||
3834 | /* target_async_mask implementation. */ | |
3835 | ||
3836 | static int | |
3837 | linux_nat_async_mask (int mask) | |
3838 | { | |
3839 | int current_state; | |
3840 | current_state = linux_nat_async_mask_value; | |
3841 | ||
3842 | if (current_state != mask) | |
3843 | { | |
3844 | if (mask == 0) | |
3845 | { | |
3846 | linux_nat_async (NULL, 0); | |
3847 | linux_nat_async_mask_value = mask; | |
3848 | /* We're in sync mode. Make sure SIGCHLD isn't handled by | |
3849 | async_sigchld_handler when we come out of sigsuspend in | |
3850 | linux_nat_wait. */ | |
3851 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
3852 | } | |
3853 | else | |
3854 | { | |
3855 | /* Restore the async handler. */ | |
3856 | sigaction (SIGCHLD, &async_sigchld_action, NULL); | |
3857 | linux_nat_async_mask_value = mask; | |
3858 | linux_nat_async (inferior_event_handler, 0); | |
3859 | } | |
3860 | } | |
3861 | ||
3862 | return current_state; | |
3863 | } | |
3864 | ||
3865 | /* Pop an event from the event pipe. */ | |
3866 | ||
3867 | static int | |
3868 | linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options) | |
3869 | { | |
3870 | struct waitpid_result event = {0}; | |
3871 | int ret; | |
3872 | ||
3873 | do | |
3874 | { | |
3875 | ret = read (linux_nat_event_pipe[0], &event, sizeof (event)); | |
3876 | } | |
3877 | while (ret == -1 && errno == EINTR); | |
3878 | ||
3879 | gdb_assert (ret == sizeof (event)); | |
3880 | ||
3881 | *ptr_status = event.status; | |
3882 | *ptr_options = event.options; | |
3883 | ||
3884 | linux_nat_num_queued_events--; | |
3885 | ||
3886 | return event.pid; | |
3887 | } | |
3888 | ||
3889 | /* Push an event into the event pipe. */ | |
3890 | ||
3891 | static void | |
3892 | linux_nat_event_pipe_push (int pid, int status, int options) | |
3893 | { | |
3894 | int ret; | |
3895 | struct waitpid_result event = {0}; | |
3896 | event.pid = pid; | |
3897 | event.status = status; | |
3898 | event.options = options; | |
3899 | ||
3900 | do | |
3901 | { | |
3902 | ret = write (linux_nat_event_pipe[1], &event, sizeof (event)); | |
3903 | gdb_assert ((ret == -1 && errno == EINTR) || ret == sizeof (event)); | |
3904 | } while (ret == -1 && errno == EINTR); | |
3905 | ||
3906 | linux_nat_num_queued_events++; | |
3907 | } | |
3908 | ||
3909 | static void | |
3910 | get_pending_events (void) | |
3911 | { | |
3912 | int status, options, pid; | |
3913 | ||
3914 | if (!linux_nat_async_enabled || !linux_nat_async_events_enabled) | |
3915 | internal_error (__FILE__, __LINE__, | |
3916 | "get_pending_events called with async masked"); | |
3917 | ||
3918 | while (1) | |
3919 | { | |
3920 | status = 0; | |
3921 | options = __WCLONE | WNOHANG; | |
3922 | ||
3923 | do | |
3924 | { | |
3925 | pid = waitpid (-1, &status, options); | |
3926 | } | |
3927 | while (pid == -1 && errno == EINTR); | |
3928 | ||
3929 | if (pid <= 0) | |
3930 | { | |
3931 | options = WNOHANG; | |
3932 | do | |
3933 | { | |
3934 | pid = waitpid (-1, &status, options); | |
3935 | } | |
3936 | while (pid == -1 && errno == EINTR); | |
3937 | } | |
3938 | ||
3939 | if (pid <= 0) | |
3940 | /* No more children reporting events. */ | |
3941 | break; | |
3942 | ||
3943 | if (debug_linux_nat_async) | |
3944 | fprintf_unfiltered (gdb_stdlog, "\ | |
3945 | get_pending_events: pid(%d), status(%x), options (%x)\n", | |
3946 | pid, status, options); | |
3947 | ||
3948 | linux_nat_event_pipe_push (pid, status, options); | |
3949 | } | |
3950 | ||
3951 | if (debug_linux_nat_async) | |
3952 | fprintf_unfiltered (gdb_stdlog, "\ | |
3953 | get_pending_events: linux_nat_num_queued_events(%d)\n", | |
3954 | linux_nat_num_queued_events); | |
3955 | } | |
3956 | ||
3957 | /* SIGCHLD handler for async mode. */ | |
3958 | ||
3959 | static void | |
3960 | async_sigchld_handler (int signo) | |
3961 | { | |
3962 | if (debug_linux_nat_async) | |
3963 | fprintf_unfiltered (gdb_stdlog, "async_sigchld_handler\n"); | |
3964 | ||
3965 | get_pending_events (); | |
3966 | } | |
3967 | ||
3968 | /* Enable or disable async SIGCHLD handling. */ | |
3969 | ||
3970 | static int | |
3971 | linux_nat_async_events (int enable) | |
3972 | { | |
3973 | int current_state = linux_nat_async_events_enabled; | |
3974 | ||
3975 | if (debug_linux_nat_async) | |
3976 | fprintf_unfiltered (gdb_stdlog, | |
3977 | "LNAE: enable(%d): linux_nat_async_events_enabled(%d), " | |
3978 | "linux_nat_num_queued_events(%d)\n", | |
3979 | enable, linux_nat_async_events_enabled, | |
3980 | linux_nat_num_queued_events); | |
3981 | ||
3982 | if (current_state != enable) | |
3983 | { | |
3984 | sigset_t mask; | |
3985 | sigemptyset (&mask); | |
3986 | sigaddset (&mask, SIGCHLD); | |
3987 | if (enable) | |
3988 | { | |
3989 | /* Unblock target events. */ | |
3990 | linux_nat_async_events_enabled = 1; | |
3991 | ||
3992 | local_event_queue_to_pipe (); | |
3993 | /* While in masked async, we may have not collected all the | |
3994 | pending events. Get them out now. */ | |
3995 | get_pending_events (); | |
3996 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
3997 | } | |
3998 | else | |
3999 | { | |
4000 | /* Block target events. */ | |
4001 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4002 | linux_nat_async_events_enabled = 0; | |
4003 | /* Get events out of queue, and make them available to | |
4004 | queued_waitpid / my_waitpid. */ | |
4005 | pipe_to_local_event_queue (); | |
4006 | } | |
4007 | } | |
4008 | ||
4009 | return current_state; | |
4010 | } | |
4011 | ||
4012 | static int async_terminal_is_ours = 1; | |
4013 | ||
4014 | /* target_terminal_inferior implementation. */ | |
4015 | ||
4016 | static void | |
4017 | linux_nat_terminal_inferior (void) | |
4018 | { | |
4019 | if (!target_is_async_p ()) | |
4020 | { | |
4021 | /* Async mode is disabled. */ | |
4022 | terminal_inferior (); | |
4023 | return; | |
4024 | } | |
4025 | ||
4026 | /* GDB should never give the terminal to the inferior, if the | |
4027 | inferior is running in the background (run&, continue&, etc.). | |
4028 | This check can be removed when the common code is fixed. */ | |
4029 | if (!sync_execution) | |
4030 | return; | |
4031 | ||
4032 | terminal_inferior (); | |
4033 | ||
4034 | if (!async_terminal_is_ours) | |
4035 | return; | |
4036 | ||
4037 | delete_file_handler (input_fd); | |
4038 | async_terminal_is_ours = 0; | |
4039 | set_sigint_trap (); | |
4040 | } | |
4041 | ||
4042 | /* target_terminal_ours implementation. */ | |
4043 | ||
4044 | void | |
4045 | linux_nat_terminal_ours (void) | |
4046 | { | |
4047 | if (!target_is_async_p ()) | |
4048 | { | |
4049 | /* Async mode is disabled. */ | |
4050 | terminal_ours (); | |
4051 | return; | |
4052 | } | |
4053 | ||
4054 | /* GDB should never give the terminal to the inferior if the | |
4055 | inferior is running in the background (run&, continue&, etc.), | |
4056 | but claiming it sure should. */ | |
4057 | terminal_ours (); | |
4058 | ||
4059 | if (!sync_execution) | |
4060 | return; | |
4061 | ||
4062 | if (async_terminal_is_ours) | |
4063 | return; | |
4064 | ||
4065 | clear_sigint_trap (); | |
4066 | add_file_handler (input_fd, stdin_event_handler, 0); | |
4067 | async_terminal_is_ours = 1; | |
4068 | } | |
4069 | ||
4070 | static void (*async_client_callback) (enum inferior_event_type event_type, | |
4071 | void *context); | |
4072 | static void *async_client_context; | |
4073 | ||
4074 | static void | |
4075 | linux_nat_async_file_handler (int error, gdb_client_data client_data) | |
4076 | { | |
4077 | async_client_callback (INF_REG_EVENT, async_client_context); | |
4078 | } | |
4079 | ||
4080 | /* target_async implementation. */ | |
4081 | ||
4082 | static void | |
4083 | linux_nat_async (void (*callback) (enum inferior_event_type event_type, | |
4084 | void *context), void *context) | |
4085 | { | |
4086 | if (linux_nat_async_mask_value == 0 || !linux_nat_async_enabled) | |
4087 | internal_error (__FILE__, __LINE__, | |
4088 | "Calling target_async when async is masked"); | |
4089 | ||
4090 | if (callback != NULL) | |
4091 | { | |
4092 | async_client_callback = callback; | |
4093 | async_client_context = context; | |
4094 | add_file_handler (linux_nat_event_pipe[0], | |
4095 | linux_nat_async_file_handler, NULL); | |
4096 | ||
4097 | linux_nat_async_events (1); | |
4098 | } | |
4099 | else | |
4100 | { | |
4101 | async_client_callback = callback; | |
4102 | async_client_context = context; | |
4103 | ||
4104 | linux_nat_async_events (0); | |
4105 | delete_file_handler (linux_nat_event_pipe[0]); | |
4106 | } | |
4107 | return; | |
4108 | } | |
4109 | ||
4110 | /* Enable/Disable async mode. */ | |
4111 | ||
4112 | static void | |
4113 | linux_nat_set_async_mode (int on) | |
4114 | { | |
4115 | if (linux_nat_async_enabled != on) | |
4116 | { | |
4117 | if (on) | |
4118 | { | |
4119 | gdb_assert (waitpid_queue == NULL); | |
4120 | sigaction (SIGCHLD, &async_sigchld_action, NULL); | |
4121 | ||
4122 | if (pipe (linux_nat_event_pipe) == -1) | |
4123 | internal_error (__FILE__, __LINE__, | |
4124 | "creating event pipe failed."); | |
4125 | ||
4126 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4127 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4128 | } | |
4129 | else | |
4130 | { | |
4131 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
4132 | ||
4133 | drain_queued_events (-1); | |
4134 | ||
4135 | linux_nat_num_queued_events = 0; | |
4136 | close (linux_nat_event_pipe[0]); | |
4137 | close (linux_nat_event_pipe[1]); | |
4138 | linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1; | |
4139 | ||
4140 | } | |
4141 | } | |
4142 | linux_nat_async_enabled = on; | |
4143 | } | |
4144 | ||
f973ed9c DJ |
4145 | void |
4146 | linux_nat_add_target (struct target_ops *t) | |
4147 | { | |
f973ed9c DJ |
4148 | /* Save the provided single-threaded target. We save this in a separate |
4149 | variable because another target we've inherited from (e.g. inf-ptrace) | |
4150 | may have saved a pointer to T; we want to use it for the final | |
4151 | process stratum target. */ | |
4152 | linux_ops_saved = *t; | |
4153 | linux_ops = &linux_ops_saved; | |
4154 | ||
4155 | /* Override some methods for multithreading. */ | |
b84876c2 | 4156 | t->to_create_inferior = linux_nat_create_inferior; |
f973ed9c DJ |
4157 | t->to_attach = linux_nat_attach; |
4158 | t->to_detach = linux_nat_detach; | |
4159 | t->to_resume = linux_nat_resume; | |
4160 | t->to_wait = linux_nat_wait; | |
4161 | t->to_xfer_partial = linux_nat_xfer_partial; | |
4162 | t->to_kill = linux_nat_kill; | |
4163 | t->to_mourn_inferior = linux_nat_mourn_inferior; | |
4164 | t->to_thread_alive = linux_nat_thread_alive; | |
4165 | t->to_pid_to_str = linux_nat_pid_to_str; | |
4166 | t->to_has_thread_control = tc_schedlock; | |
4167 | ||
b84876c2 PA |
4168 | t->to_can_async_p = linux_nat_can_async_p; |
4169 | t->to_is_async_p = linux_nat_is_async_p; | |
4170 | t->to_async = linux_nat_async; | |
4171 | t->to_async_mask = linux_nat_async_mask; | |
4172 | t->to_terminal_inferior = linux_nat_terminal_inferior; | |
4173 | t->to_terminal_ours = linux_nat_terminal_ours; | |
4174 | ||
f973ed9c DJ |
4175 | /* We don't change the stratum; this target will sit at |
4176 | process_stratum and thread_db will set at thread_stratum. This | |
4177 | is a little strange, since this is a multi-threaded-capable | |
4178 | target, but we want to be on the stack below thread_db, and we | |
4179 | also want to be used for single-threaded processes. */ | |
4180 | ||
4181 | add_target (t); | |
4182 | ||
4183 | /* TODO: Eliminate this and have libthread_db use | |
4184 | find_target_beneath. */ | |
4185 | thread_db_init (t); | |
4186 | } | |
4187 | ||
9f0bdab8 DJ |
4188 | /* Register a method to call whenever a new thread is attached. */ |
4189 | void | |
4190 | linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t)) | |
4191 | { | |
4192 | /* Save the pointer. We only support a single registered instance | |
4193 | of the GNU/Linux native target, so we do not need to map this to | |
4194 | T. */ | |
4195 | linux_nat_new_thread = new_thread; | |
4196 | } | |
4197 | ||
4198 | /* Return the saved siginfo associated with PTID. */ | |
4199 | struct siginfo * | |
4200 | linux_nat_get_siginfo (ptid_t ptid) | |
4201 | { | |
4202 | struct lwp_info *lp = find_lwp_pid (ptid); | |
4203 | ||
4204 | gdb_assert (lp != NULL); | |
4205 | ||
4206 | return &lp->siginfo; | |
4207 | } | |
4208 | ||
d6b0e80f AC |
4209 | void |
4210 | _initialize_linux_nat (void) | |
4211 | { | |
b84876c2 | 4212 | sigset_t mask; |
dba24537 | 4213 | |
1bedd215 AC |
4214 | add_info ("proc", linux_nat_info_proc_cmd, _("\ |
4215 | Show /proc process information about any running process.\n\ | |
dba24537 AC |
4216 | Specify any process id, or use the program being debugged by default.\n\ |
4217 | Specify any of the following keywords for detailed info:\n\ | |
4218 | mappings -- list of mapped memory regions.\n\ | |
4219 | stat -- list a bunch of random process info.\n\ | |
4220 | status -- list a different bunch of random process info.\n\ | |
1bedd215 | 4221 | all -- list all available /proc info.")); |
d6b0e80f | 4222 | |
b84876c2 PA |
4223 | add_setshow_zinteger_cmd ("lin-lwp", class_maintenance, |
4224 | &debug_linux_nat, _("\ | |
4225 | Set debugging of GNU/Linux lwp module."), _("\ | |
4226 | Show debugging of GNU/Linux lwp module."), _("\ | |
4227 | Enables printf debugging output."), | |
4228 | NULL, | |
4229 | show_debug_linux_nat, | |
4230 | &setdebuglist, &showdebuglist); | |
4231 | ||
4232 | add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance, | |
4233 | &debug_linux_nat_async, _("\ | |
4234 | Set debugging of GNU/Linux async lwp module."), _("\ | |
4235 | Show debugging of GNU/Linux async lwp module."), _("\ | |
4236 | Enables printf debugging output."), | |
4237 | NULL, | |
4238 | show_debug_linux_nat_async, | |
4239 | &setdebuglist, &showdebuglist); | |
4240 | ||
4241 | add_setshow_boolean_cmd ("linux-async", class_maintenance, | |
4242 | &linux_async_permitted_1, _("\ | |
4243 | Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4244 | Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\ | |
4245 | Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."), | |
4246 | set_maintenance_linux_async_permitted, | |
4247 | show_maintenance_linux_async_permitted, | |
4248 | &maintenance_set_cmdlist, | |
4249 | &maintenance_show_cmdlist); | |
4250 | ||
4251 | /* Block SIGCHLD by default. Doing this early prevents it getting | |
4252 | unblocked if an exception is thrown due to an error while the | |
4253 | inferior is starting (sigsetjmp/siglongjmp). */ | |
4254 | sigemptyset (&mask); | |
4255 | sigaddset (&mask, SIGCHLD); | |
4256 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
4257 | ||
4258 | /* Save this mask as the default. */ | |
d6b0e80f AC |
4259 | sigprocmask (SIG_SETMASK, NULL, &normal_mask); |
4260 | ||
b84876c2 PA |
4261 | /* The synchronous SIGCHLD handler. */ |
4262 | sync_sigchld_action.sa_handler = sigchld_handler; | |
4263 | sigemptyset (&sync_sigchld_action.sa_mask); | |
4264 | sync_sigchld_action.sa_flags = SA_RESTART; | |
4265 | ||
4266 | /* Make it the default. */ | |
4267 | sigaction (SIGCHLD, &sync_sigchld_action, NULL); | |
d6b0e80f AC |
4268 | |
4269 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4270 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4271 | sigdelset (&suspend_mask, SIGCHLD); | |
4272 | ||
b84876c2 PA |
4273 | /* SIGCHLD handler for async mode. */ |
4274 | async_sigchld_action.sa_handler = async_sigchld_handler; | |
4275 | sigemptyset (&async_sigchld_action.sa_mask); | |
4276 | async_sigchld_action.sa_flags = SA_RESTART; | |
d6b0e80f | 4277 | |
b84876c2 PA |
4278 | /* Install the default mode. */ |
4279 | linux_nat_set_async_mode (linux_async_permitted); | |
d6b0e80f AC |
4280 | } |
4281 | \f | |
4282 | ||
4283 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4284 | the GNU/Linux Threads library and therefore doesn't really belong | |
4285 | here. */ | |
4286 | ||
4287 | /* Read variable NAME in the target and return its value if found. | |
4288 | Otherwise return zero. It is assumed that the type of the variable | |
4289 | is `int'. */ | |
4290 | ||
4291 | static int | |
4292 | get_signo (const char *name) | |
4293 | { | |
4294 | struct minimal_symbol *ms; | |
4295 | int signo; | |
4296 | ||
4297 | ms = lookup_minimal_symbol (name, NULL, NULL); | |
4298 | if (ms == NULL) | |
4299 | return 0; | |
4300 | ||
8e70166d | 4301 | if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo, |
d6b0e80f AC |
4302 | sizeof (signo)) != 0) |
4303 | return 0; | |
4304 | ||
4305 | return signo; | |
4306 | } | |
4307 | ||
4308 | /* Return the set of signals used by the threads library in *SET. */ | |
4309 | ||
4310 | void | |
4311 | lin_thread_get_thread_signals (sigset_t *set) | |
4312 | { | |
4313 | struct sigaction action; | |
4314 | int restart, cancel; | |
b84876c2 | 4315 | sigset_t blocked_mask; |
d6b0e80f | 4316 | |
b84876c2 | 4317 | sigemptyset (&blocked_mask); |
d6b0e80f AC |
4318 | sigemptyset (set); |
4319 | ||
4320 | restart = get_signo ("__pthread_sig_restart"); | |
17fbb0bd DJ |
4321 | cancel = get_signo ("__pthread_sig_cancel"); |
4322 | ||
4323 | /* LinuxThreads normally uses the first two RT signals, but in some legacy | |
4324 | cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does | |
4325 | not provide any way for the debugger to query the signal numbers - | |
4326 | fortunately they don't change! */ | |
4327 | ||
d6b0e80f | 4328 | if (restart == 0) |
17fbb0bd | 4329 | restart = __SIGRTMIN; |
d6b0e80f | 4330 | |
d6b0e80f | 4331 | if (cancel == 0) |
17fbb0bd | 4332 | cancel = __SIGRTMIN + 1; |
d6b0e80f AC |
4333 | |
4334 | sigaddset (set, restart); | |
4335 | sigaddset (set, cancel); | |
4336 | ||
4337 | /* The GNU/Linux Threads library makes terminating threads send a | |
4338 | special "cancel" signal instead of SIGCHLD. Make sure we catch | |
4339 | those (to prevent them from terminating GDB itself, which is | |
4340 | likely to be their default action) and treat them the same way as | |
4341 | SIGCHLD. */ | |
4342 | ||
4343 | action.sa_handler = sigchld_handler; | |
4344 | sigemptyset (&action.sa_mask); | |
58aecb61 | 4345 | action.sa_flags = SA_RESTART; |
d6b0e80f AC |
4346 | sigaction (cancel, &action, NULL); |
4347 | ||
4348 | /* We block the "cancel" signal throughout this code ... */ | |
4349 | sigaddset (&blocked_mask, cancel); | |
4350 | sigprocmask (SIG_BLOCK, &blocked_mask, NULL); | |
4351 | ||
4352 | /* ... except during a sigsuspend. */ | |
4353 | sigdelset (&suspend_mask, cancel); | |
4354 | } |