Commit | Line | Data |
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da6d8c04 | 1 | /* Low level interface to ptrace, for the remote server for GDB. |
5544ad89 | 2 | Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004 |
da6d8c04 DJ |
3 | Free Software Foundation, Inc. |
4 | ||
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, | |
20 | Boston, MA 02111-1307, USA. */ | |
21 | ||
22 | #include "server.h" | |
58caa3dc | 23 | #include "linux-low.h" |
da6d8c04 | 24 | |
58caa3dc | 25 | #include <sys/wait.h> |
da6d8c04 DJ |
26 | #include <stdio.h> |
27 | #include <sys/param.h> | |
28 | #include <sys/dir.h> | |
29 | #include <sys/ptrace.h> | |
30 | #include <sys/user.h> | |
31 | #include <signal.h> | |
32 | #include <sys/ioctl.h> | |
33 | #include <fcntl.h> | |
d07c63e7 | 34 | #include <string.h> |
0a30fbc4 DJ |
35 | #include <stdlib.h> |
36 | #include <unistd.h> | |
fa6a77dc | 37 | #include <errno.h> |
da6d8c04 | 38 | |
0d62e5e8 DJ |
39 | /* ``all_threads'' is keyed by the LWP ID - it should be the thread ID instead, |
40 | however. This requires changing the ID in place when we go from !using_threads | |
41 | to using_threads, immediately. | |
611cb4a5 | 42 | |
0d62e5e8 DJ |
43 | ``all_processes'' is keyed by the process ID - which on Linux is (presently) |
44 | the same as the LWP ID. */ | |
45 | ||
46 | struct inferior_list all_processes; | |
47 | ||
48 | /* FIXME this is a bit of a hack, and could be removed. */ | |
49 | int stopping_threads; | |
50 | ||
51 | /* FIXME make into a target method? */ | |
52 | int using_threads; | |
53 | ||
54 | static void linux_resume_one_process (struct inferior_list_entry *entry, | |
55 | int step, int signal); | |
64386c31 | 56 | static void linux_resume (struct thread_resume *resume_info); |
0d62e5e8 DJ |
57 | static void stop_all_processes (void); |
58 | static int linux_wait_for_event (struct thread_info *child); | |
59 | ||
60 | struct pending_signals | |
61 | { | |
62 | int signal; | |
63 | struct pending_signals *prev; | |
64 | }; | |
611cb4a5 | 65 | |
d844cde6 | 66 | #define PTRACE_ARG3_TYPE long |
c6ecbae5 | 67 | #define PTRACE_XFER_TYPE long |
da6d8c04 | 68 | |
58caa3dc DJ |
69 | #ifdef HAVE_LINUX_REGSETS |
70 | static int use_regsets_p = 1; | |
71 | #endif | |
72 | ||
0d62e5e8 DJ |
73 | int debug_threads = 0; |
74 | ||
75 | #define pid_of(proc) ((proc)->head.id) | |
76 | ||
77 | /* FIXME: Delete eventually. */ | |
78 | #define inferior_pid (pid_of (get_thread_process (current_inferior))) | |
79 | ||
80 | /* This function should only be called if the process got a SIGTRAP. | |
81 | The SIGTRAP could mean several things. | |
82 | ||
83 | On i386, where decr_pc_after_break is non-zero: | |
84 | If we were single-stepping this process using PTRACE_SINGLESTEP, | |
85 | we will get only the one SIGTRAP (even if the instruction we | |
86 | stepped over was a breakpoint). The value of $eip will be the | |
87 | next instruction. | |
88 | If we continue the process using PTRACE_CONT, we will get a | |
89 | SIGTRAP when we hit a breakpoint. The value of $eip will be | |
90 | the instruction after the breakpoint (i.e. needs to be | |
91 | decremented). If we report the SIGTRAP to GDB, we must also | |
92 | report the undecremented PC. If we cancel the SIGTRAP, we | |
93 | must resume at the decremented PC. | |
94 | ||
95 | (Presumably, not yet tested) On a non-decr_pc_after_break machine | |
96 | with hardware or kernel single-step: | |
97 | If we single-step over a breakpoint instruction, our PC will | |
98 | point at the following instruction. If we continue and hit a | |
99 | breakpoint instruction, our PC will point at the breakpoint | |
100 | instruction. */ | |
101 | ||
102 | static CORE_ADDR | |
103 | get_stop_pc (void) | |
104 | { | |
105 | CORE_ADDR stop_pc = (*the_low_target.get_pc) (); | |
106 | ||
107 | if (get_thread_process (current_inferior)->stepping) | |
108 | return stop_pc; | |
109 | else | |
110 | return stop_pc - the_low_target.decr_pc_after_break; | |
111 | } | |
ce3a066d | 112 | |
0d62e5e8 DJ |
113 | static void * |
114 | add_process (int pid) | |
611cb4a5 | 115 | { |
0d62e5e8 DJ |
116 | struct process_info *process; |
117 | ||
118 | process = (struct process_info *) malloc (sizeof (*process)); | |
119 | memset (process, 0, sizeof (*process)); | |
120 | ||
121 | process->head.id = pid; | |
122 | ||
123 | /* Default to tid == lwpid == pid. */ | |
124 | process->tid = pid; | |
125 | process->lwpid = pid; | |
126 | ||
127 | add_inferior_to_list (&all_processes, &process->head); | |
128 | ||
129 | return process; | |
130 | } | |
611cb4a5 | 131 | |
da6d8c04 DJ |
132 | /* Start an inferior process and returns its pid. |
133 | ALLARGS is a vector of program-name and args. */ | |
134 | ||
ce3a066d DJ |
135 | static int |
136 | linux_create_inferior (char *program, char **allargs) | |
da6d8c04 | 137 | { |
0d62e5e8 | 138 | void *new_process; |
da6d8c04 DJ |
139 | int pid; |
140 | ||
141 | pid = fork (); | |
142 | if (pid < 0) | |
143 | perror_with_name ("fork"); | |
144 | ||
145 | if (pid == 0) | |
146 | { | |
147 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
148 | ||
254787d4 | 149 | signal (__SIGRTMIN + 1, SIG_DFL); |
0d62e5e8 | 150 | |
a9fa9f7d DJ |
151 | setpgid (0, 0); |
152 | ||
da6d8c04 DJ |
153 | execv (program, allargs); |
154 | ||
155 | fprintf (stderr, "Cannot exec %s: %s.\n", program, | |
d07c63e7 | 156 | strerror (errno)); |
da6d8c04 DJ |
157 | fflush (stderr); |
158 | _exit (0177); | |
159 | } | |
160 | ||
0d62e5e8 DJ |
161 | new_process = add_process (pid); |
162 | add_thread (pid, new_process); | |
611cb4a5 | 163 | |
a9fa9f7d | 164 | return pid; |
da6d8c04 DJ |
165 | } |
166 | ||
167 | /* Attach to an inferior process. */ | |
168 | ||
0d62e5e8 DJ |
169 | void |
170 | linux_attach_lwp (int pid, int tid) | |
da6d8c04 | 171 | { |
0d62e5e8 | 172 | struct process_info *new_process; |
611cb4a5 | 173 | |
da6d8c04 DJ |
174 | if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0) |
175 | { | |
176 | fprintf (stderr, "Cannot attach to process %d: %s (%d)\n", pid, | |
43d5792c | 177 | strerror (errno), errno); |
da6d8c04 | 178 | fflush (stderr); |
0d62e5e8 DJ |
179 | |
180 | /* If we fail to attach to an LWP, just return. */ | |
181 | if (!using_threads) | |
182 | _exit (0177); | |
183 | return; | |
da6d8c04 DJ |
184 | } |
185 | ||
0d62e5e8 DJ |
186 | new_process = (struct process_info *) add_process (pid); |
187 | add_thread (tid, new_process); | |
188 | ||
189 | /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH | |
190 | brings it to a halt. We should ignore that SIGSTOP and resume the process | |
191 | (unless this is the first process, in which case the flag will be cleared | |
192 | in linux_attach). | |
193 | ||
194 | On the other hand, if we are currently trying to stop all threads, we | |
195 | should treat the new thread as if we had sent it a SIGSTOP. This works | |
196 | because we are guaranteed that add_process added us to the end of the | |
197 | list, and so the new thread has not yet reached wait_for_sigstop (but | |
198 | will). */ | |
199 | if (! stopping_threads) | |
200 | new_process->stop_expected = 1; | |
201 | } | |
202 | ||
203 | int | |
204 | linux_attach (int pid) | |
205 | { | |
206 | struct process_info *process; | |
207 | ||
208 | linux_attach_lwp (pid, pid); | |
209 | ||
210 | /* Don't ignore the initial SIGSTOP if we just attached to this process. */ | |
211 | process = (struct process_info *) find_inferior_id (&all_processes, pid); | |
212 | process->stop_expected = 0; | |
213 | ||
da6d8c04 DJ |
214 | return 0; |
215 | } | |
216 | ||
217 | /* Kill the inferior process. Make us have no inferior. */ | |
218 | ||
ce3a066d | 219 | static void |
0d62e5e8 | 220 | linux_kill_one_process (struct inferior_list_entry *entry) |
da6d8c04 | 221 | { |
0d62e5e8 DJ |
222 | struct thread_info *thread = (struct thread_info *) entry; |
223 | struct process_info *process = get_thread_process (thread); | |
224 | int wstat; | |
225 | ||
226 | do | |
227 | { | |
228 | ptrace (PTRACE_KILL, pid_of (process), 0, 0); | |
229 | ||
230 | /* Make sure it died. The loop is most likely unnecessary. */ | |
231 | wstat = linux_wait_for_event (thread); | |
232 | } while (WIFSTOPPED (wstat)); | |
da6d8c04 DJ |
233 | } |
234 | ||
0d62e5e8 DJ |
235 | static void |
236 | linux_kill (void) | |
237 | { | |
238 | for_each_inferior (&all_threads, linux_kill_one_process); | |
239 | } | |
240 | ||
6ad8ae5c DJ |
241 | static void |
242 | linux_detach_one_process (struct inferior_list_entry *entry) | |
243 | { | |
244 | struct thread_info *thread = (struct thread_info *) entry; | |
245 | struct process_info *process = get_thread_process (thread); | |
246 | ||
247 | ptrace (PTRACE_DETACH, pid_of (process), 0, 0); | |
248 | } | |
249 | ||
250 | static void | |
251 | linux_detach (void) | |
252 | { | |
253 | for_each_inferior (&all_threads, linux_detach_one_process); | |
254 | } | |
255 | ||
256 | /* Return nonzero if the given thread is still alive. */ | |
0d62e5e8 DJ |
257 | static int |
258 | linux_thread_alive (int tid) | |
259 | { | |
260 | if (find_inferior_id (&all_threads, tid) != NULL) | |
261 | return 1; | |
262 | else | |
263 | return 0; | |
264 | } | |
265 | ||
266 | /* Return nonzero if this process stopped at a breakpoint which | |
267 | no longer appears to be inserted. Also adjust the PC | |
268 | appropriately to resume where the breakpoint used to be. */ | |
ce3a066d | 269 | static int |
0d62e5e8 | 270 | check_removed_breakpoint (struct process_info *event_child) |
da6d8c04 | 271 | { |
0d62e5e8 DJ |
272 | CORE_ADDR stop_pc; |
273 | struct thread_info *saved_inferior; | |
274 | ||
275 | if (event_child->pending_is_breakpoint == 0) | |
276 | return 0; | |
277 | ||
278 | if (debug_threads) | |
279 | fprintf (stderr, "Checking for breakpoint.\n"); | |
280 | ||
281 | saved_inferior = current_inferior; | |
282 | current_inferior = get_process_thread (event_child); | |
283 | ||
284 | stop_pc = get_stop_pc (); | |
285 | ||
286 | /* If the PC has changed since we stopped, then we shouldn't do | |
287 | anything. This happens if, for instance, GDB handled the | |
288 | decr_pc_after_break subtraction itself. */ | |
289 | if (stop_pc != event_child->pending_stop_pc) | |
290 | { | |
291 | if (debug_threads) | |
292 | fprintf (stderr, "Ignoring, PC was changed.\n"); | |
293 | ||
294 | event_child->pending_is_breakpoint = 0; | |
295 | current_inferior = saved_inferior; | |
296 | return 0; | |
297 | } | |
298 | ||
299 | /* If the breakpoint is still there, we will report hitting it. */ | |
300 | if ((*the_low_target.breakpoint_at) (stop_pc)) | |
301 | { | |
302 | if (debug_threads) | |
303 | fprintf (stderr, "Ignoring, breakpoint is still present.\n"); | |
304 | current_inferior = saved_inferior; | |
305 | return 0; | |
306 | } | |
307 | ||
308 | if (debug_threads) | |
309 | fprintf (stderr, "Removed breakpoint.\n"); | |
310 | ||
311 | /* For decr_pc_after_break targets, here is where we perform the | |
312 | decrement. We go immediately from this function to resuming, | |
313 | and can not safely call get_stop_pc () again. */ | |
314 | if (the_low_target.set_pc != NULL) | |
315 | (*the_low_target.set_pc) (stop_pc); | |
316 | ||
317 | /* We consumed the pending SIGTRAP. */ | |
5544ad89 | 318 | event_child->pending_is_breakpoint = 0; |
0d62e5e8 DJ |
319 | event_child->status_pending_p = 0; |
320 | event_child->status_pending = 0; | |
321 | ||
322 | current_inferior = saved_inferior; | |
da6d8c04 DJ |
323 | return 1; |
324 | } | |
325 | ||
0d62e5e8 DJ |
326 | /* Return 1 if this process has an interesting status pending. This function |
327 | may silently resume an inferior process. */ | |
611cb4a5 | 328 | static int |
0d62e5e8 DJ |
329 | status_pending_p (struct inferior_list_entry *entry, void *dummy) |
330 | { | |
331 | struct process_info *process = (struct process_info *) entry; | |
332 | ||
333 | if (process->status_pending_p) | |
334 | if (check_removed_breakpoint (process)) | |
335 | { | |
336 | /* This thread was stopped at a breakpoint, and the breakpoint | |
337 | is now gone. We were told to continue (or step...) all threads, | |
338 | so GDB isn't trying to single-step past this breakpoint. | |
339 | So instead of reporting the old SIGTRAP, pretend we got to | |
340 | the breakpoint just after it was removed instead of just | |
341 | before; resume the process. */ | |
342 | linux_resume_one_process (&process->head, 0, 0); | |
343 | return 0; | |
344 | } | |
345 | ||
346 | return process->status_pending_p; | |
347 | } | |
348 | ||
349 | static void | |
350 | linux_wait_for_process (struct process_info **childp, int *wstatp) | |
611cb4a5 | 351 | { |
0d62e5e8 DJ |
352 | int ret; |
353 | int to_wait_for = -1; | |
354 | ||
355 | if (*childp != NULL) | |
356 | to_wait_for = (*childp)->lwpid; | |
611cb4a5 DJ |
357 | |
358 | while (1) | |
359 | { | |
0d62e5e8 DJ |
360 | ret = waitpid (to_wait_for, wstatp, WNOHANG); |
361 | ||
362 | if (ret == -1) | |
363 | { | |
364 | if (errno != ECHILD) | |
365 | perror_with_name ("waitpid"); | |
366 | } | |
367 | else if (ret > 0) | |
368 | break; | |
369 | ||
370 | ret = waitpid (to_wait_for, wstatp, WNOHANG | __WCLONE); | |
371 | ||
372 | if (ret == -1) | |
373 | { | |
374 | if (errno != ECHILD) | |
375 | perror_with_name ("waitpid (WCLONE)"); | |
376 | } | |
377 | else if (ret > 0) | |
378 | break; | |
379 | ||
380 | usleep (1000); | |
381 | } | |
382 | ||
383 | if (debug_threads | |
384 | && (!WIFSTOPPED (*wstatp) | |
385 | || (WSTOPSIG (*wstatp) != 32 | |
386 | && WSTOPSIG (*wstatp) != 33))) | |
387 | fprintf (stderr, "Got an event from %d (%x)\n", ret, *wstatp); | |
388 | ||
389 | if (to_wait_for == -1) | |
390 | *childp = (struct process_info *) find_inferior_id (&all_processes, ret); | |
391 | ||
392 | (*childp)->stopped = 1; | |
393 | (*childp)->pending_is_breakpoint = 0; | |
394 | ||
395 | if (debug_threads | |
396 | && WIFSTOPPED (*wstatp)) | |
397 | { | |
398 | current_inferior = (struct thread_info *) | |
399 | find_inferior_id (&all_threads, (*childp)->tid); | |
400 | /* For testing only; i386_stop_pc prints out a diagnostic. */ | |
401 | if (the_low_target.get_pc != NULL) | |
402 | get_stop_pc (); | |
403 | } | |
404 | } | |
611cb4a5 | 405 | |
0d62e5e8 DJ |
406 | static int |
407 | linux_wait_for_event (struct thread_info *child) | |
408 | { | |
409 | CORE_ADDR stop_pc; | |
410 | struct process_info *event_child; | |
411 | int wstat; | |
412 | ||
413 | /* Check for a process with a pending status. */ | |
414 | /* It is possible that the user changed the pending task's registers since | |
415 | it stopped. We correctly handle the change of PC if we hit a breakpoint | |
e5379b03 | 416 | (in check_removed_breakpoint); signals should be reported anyway. */ |
0d62e5e8 DJ |
417 | if (child == NULL) |
418 | { | |
419 | event_child = (struct process_info *) | |
420 | find_inferior (&all_processes, status_pending_p, NULL); | |
421 | if (debug_threads && event_child) | |
422 | fprintf (stderr, "Got a pending child %d\n", event_child->lwpid); | |
423 | } | |
424 | else | |
425 | { | |
426 | event_child = get_thread_process (child); | |
427 | if (event_child->status_pending_p | |
428 | && check_removed_breakpoint (event_child)) | |
429 | event_child = NULL; | |
430 | } | |
611cb4a5 | 431 | |
0d62e5e8 DJ |
432 | if (event_child != NULL) |
433 | { | |
434 | if (event_child->status_pending_p) | |
611cb4a5 | 435 | { |
0d62e5e8 DJ |
436 | if (debug_threads) |
437 | fprintf (stderr, "Got an event from pending child %d (%04x)\n", | |
438 | event_child->lwpid, event_child->status_pending); | |
439 | wstat = event_child->status_pending; | |
440 | event_child->status_pending_p = 0; | |
441 | event_child->status_pending = 0; | |
442 | current_inferior = get_process_thread (event_child); | |
443 | return wstat; | |
444 | } | |
445 | } | |
446 | ||
447 | /* We only enter this loop if no process has a pending wait status. Thus | |
448 | any action taken in response to a wait status inside this loop is | |
449 | responding as soon as we detect the status, not after any pending | |
450 | events. */ | |
451 | while (1) | |
452 | { | |
453 | if (child == NULL) | |
454 | event_child = NULL; | |
455 | else | |
456 | event_child = get_thread_process (child); | |
457 | ||
458 | linux_wait_for_process (&event_child, &wstat); | |
459 | ||
460 | if (event_child == NULL) | |
461 | error ("event from unknown child"); | |
611cb4a5 | 462 | |
0d62e5e8 DJ |
463 | current_inferior = (struct thread_info *) |
464 | find_inferior_id (&all_threads, event_child->tid); | |
465 | ||
466 | if (using_threads) | |
467 | { | |
468 | /* Check for thread exit. */ | |
469 | if (! WIFSTOPPED (wstat)) | |
611cb4a5 | 470 | { |
0d62e5e8 DJ |
471 | if (debug_threads) |
472 | fprintf (stderr, "Thread %d (LWP %d) exiting\n", | |
473 | event_child->tid, event_child->head.id); | |
474 | ||
475 | /* If the last thread is exiting, just return. */ | |
476 | if (all_threads.head == all_threads.tail) | |
477 | return wstat; | |
478 | ||
479 | dead_thread_notify (event_child->tid); | |
480 | ||
481 | remove_inferior (&all_processes, &event_child->head); | |
482 | free (event_child); | |
483 | remove_thread (current_inferior); | |
484 | current_inferior = (struct thread_info *) all_threads.head; | |
485 | ||
486 | /* If we were waiting for this particular child to do something... | |
487 | well, it did something. */ | |
488 | if (child != NULL) | |
489 | return wstat; | |
490 | ||
491 | /* Wait for a more interesting event. */ | |
611cb4a5 DJ |
492 | continue; |
493 | } | |
494 | ||
0d62e5e8 DJ |
495 | if (WIFSTOPPED (wstat) |
496 | && WSTOPSIG (wstat) == SIGSTOP | |
497 | && event_child->stop_expected) | |
498 | { | |
499 | if (debug_threads) | |
500 | fprintf (stderr, "Expected stop.\n"); | |
501 | event_child->stop_expected = 0; | |
502 | linux_resume_one_process (&event_child->head, | |
503 | event_child->stepping, 0); | |
504 | continue; | |
505 | } | |
611cb4a5 | 506 | |
0d62e5e8 DJ |
507 | /* FIXME drow/2002-06-09: Get signal numbers from the inferior's |
508 | thread library? */ | |
509 | if (WIFSTOPPED (wstat) | |
254787d4 DJ |
510 | && (WSTOPSIG (wstat) == __SIGRTMIN |
511 | || WSTOPSIG (wstat) == __SIGRTMIN + 1)) | |
611cb4a5 | 512 | { |
0d62e5e8 DJ |
513 | if (debug_threads) |
514 | fprintf (stderr, "Ignored signal %d for %d (LWP %d).\n", | |
515 | WSTOPSIG (wstat), event_child->tid, | |
516 | event_child->head.id); | |
517 | linux_resume_one_process (&event_child->head, | |
518 | event_child->stepping, | |
519 | WSTOPSIG (wstat)); | |
520 | continue; | |
521 | } | |
522 | } | |
611cb4a5 | 523 | |
0d62e5e8 DJ |
524 | /* If this event was not handled above, and is not a SIGTRAP, report |
525 | it. */ | |
526 | if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGTRAP) | |
527 | return wstat; | |
611cb4a5 | 528 | |
0d62e5e8 DJ |
529 | /* If this target does not support breakpoints, we simply report the |
530 | SIGTRAP; it's of no concern to us. */ | |
531 | if (the_low_target.get_pc == NULL) | |
532 | return wstat; | |
533 | ||
534 | stop_pc = get_stop_pc (); | |
535 | ||
536 | /* bp_reinsert will only be set if we were single-stepping. | |
537 | Notice that we will resume the process after hitting | |
538 | a gdbserver breakpoint; single-stepping to/over one | |
539 | is not supported (yet). */ | |
540 | if (event_child->bp_reinsert != 0) | |
541 | { | |
542 | if (debug_threads) | |
543 | fprintf (stderr, "Reinserted breakpoint.\n"); | |
544 | reinsert_breakpoint (event_child->bp_reinsert); | |
545 | event_child->bp_reinsert = 0; | |
546 | ||
547 | /* Clear the single-stepping flag and SIGTRAP as we resume. */ | |
548 | linux_resume_one_process (&event_child->head, 0, 0); | |
549 | continue; | |
550 | } | |
551 | ||
552 | if (debug_threads) | |
553 | fprintf (stderr, "Hit a (non-reinsert) breakpoint.\n"); | |
554 | ||
555 | if (check_breakpoints (stop_pc) != 0) | |
556 | { | |
557 | /* We hit one of our own breakpoints. We mark it as a pending | |
e5379b03 | 558 | breakpoint, so that check_removed_breakpoint () will do the PC |
0d62e5e8 DJ |
559 | adjustment for us at the appropriate time. */ |
560 | event_child->pending_is_breakpoint = 1; | |
561 | event_child->pending_stop_pc = stop_pc; | |
562 | ||
563 | /* Now we need to put the breakpoint back. We continue in the event | |
564 | loop instead of simply replacing the breakpoint right away, | |
565 | in order to not lose signals sent to the thread that hit the | |
566 | breakpoint. Unfortunately this increases the window where another | |
567 | thread could sneak past the removed breakpoint. For the current | |
568 | use of server-side breakpoints (thread creation) this is | |
569 | acceptable; but it needs to be considered before this breakpoint | |
570 | mechanism can be used in more general ways. For some breakpoints | |
571 | it may be necessary to stop all other threads, but that should | |
572 | be avoided where possible. | |
573 | ||
574 | If breakpoint_reinsert_addr is NULL, that means that we can | |
575 | use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint, | |
576 | mark it for reinsertion, and single-step. | |
577 | ||
578 | Otherwise, call the target function to figure out where we need | |
579 | our temporary breakpoint, create it, and continue executing this | |
580 | process. */ | |
581 | if (the_low_target.breakpoint_reinsert_addr == NULL) | |
582 | { | |
583 | event_child->bp_reinsert = stop_pc; | |
584 | uninsert_breakpoint (stop_pc); | |
585 | linux_resume_one_process (&event_child->head, 1, 0); | |
586 | } | |
587 | else | |
588 | { | |
589 | reinsert_breakpoint_by_bp | |
590 | (stop_pc, (*the_low_target.breakpoint_reinsert_addr) ()); | |
591 | linux_resume_one_process (&event_child->head, 0, 0); | |
611cb4a5 | 592 | } |
0d62e5e8 DJ |
593 | |
594 | continue; | |
595 | } | |
596 | ||
597 | /* If we were single-stepping, we definitely want to report the | |
598 | SIGTRAP. The single-step operation has completed, so also | |
aa691b87 | 599 | clear the stepping flag; in general this does not matter, |
0d62e5e8 DJ |
600 | because the SIGTRAP will be reported to the client, which |
601 | will give us a new action for this thread, but clear it for | |
602 | consistency anyway. It's safe to clear the stepping flag | |
603 | because the only consumer of get_stop_pc () after this point | |
e5379b03 | 604 | is check_removed_breakpoint, and pending_is_breakpoint is not |
0d62e5e8 DJ |
605 | set. It might be wiser to use a step_completed flag instead. */ |
606 | if (event_child->stepping) | |
607 | { | |
608 | event_child->stepping = 0; | |
609 | return wstat; | |
610 | } | |
611 | ||
612 | /* A SIGTRAP that we can't explain. It may have been a breakpoint. | |
613 | Check if it is a breakpoint, and if so mark the process information | |
614 | accordingly. This will handle both the necessary fiddling with the | |
615 | PC on decr_pc_after_break targets and suppressing extra threads | |
616 | hitting a breakpoint if two hit it at once and then GDB removes it | |
617 | after the first is reported. Arguably it would be better to report | |
618 | multiple threads hitting breakpoints simultaneously, but the current | |
619 | remote protocol does not allow this. */ | |
620 | if ((*the_low_target.breakpoint_at) (stop_pc)) | |
621 | { | |
622 | event_child->pending_is_breakpoint = 1; | |
623 | event_child->pending_stop_pc = stop_pc; | |
611cb4a5 DJ |
624 | } |
625 | ||
626 | return wstat; | |
627 | } | |
0d62e5e8 | 628 | |
611cb4a5 DJ |
629 | /* NOTREACHED */ |
630 | return 0; | |
631 | } | |
632 | ||
0d62e5e8 | 633 | /* Wait for process, returns status. */ |
da6d8c04 | 634 | |
ce3a066d DJ |
635 | static unsigned char |
636 | linux_wait (char *status) | |
da6d8c04 | 637 | { |
e5f1222d | 638 | int w; |
0d62e5e8 DJ |
639 | struct thread_info *child = NULL; |
640 | ||
641 | retry: | |
642 | /* If we were only supposed to resume one thread, only wait for | |
643 | that thread - if it's still alive. If it died, however - which | |
644 | can happen if we're coming from the thread death case below - | |
645 | then we need to make sure we restart the other threads. We could | |
646 | pick a thread at random or restart all; restarting all is less | |
647 | arbitrary. */ | |
648 | if (cont_thread > 0) | |
649 | { | |
650 | child = (struct thread_info *) find_inferior_id (&all_threads, | |
651 | cont_thread); | |
652 | ||
653 | /* No stepping, no signal - unless one is pending already, of course. */ | |
654 | if (child == NULL) | |
64386c31 DJ |
655 | { |
656 | struct thread_resume resume_info; | |
657 | resume_info.thread = -1; | |
658 | resume_info.step = resume_info.sig = resume_info.leave_stopped = 0; | |
659 | linux_resume (&resume_info); | |
660 | } | |
0d62e5e8 | 661 | } |
da6d8c04 DJ |
662 | |
663 | enable_async_io (); | |
62ea82f5 | 664 | unblock_async_io (); |
0d62e5e8 DJ |
665 | w = linux_wait_for_event (child); |
666 | stop_all_processes (); | |
da6d8c04 | 667 | disable_async_io (); |
da6d8c04 | 668 | |
0d62e5e8 DJ |
669 | /* If we are waiting for a particular child, and it exited, |
670 | linux_wait_for_event will return its exit status. Similarly if | |
671 | the last child exited. If this is not the last child, however, | |
672 | do not report it as exited until there is a 'thread exited' response | |
673 | available in the remote protocol. Instead, just wait for another event. | |
674 | This should be safe, because if the thread crashed we will already | |
675 | have reported the termination signal to GDB; that should stop any | |
676 | in-progress stepping operations, etc. | |
677 | ||
678 | Report the exit status of the last thread to exit. This matches | |
679 | LinuxThreads' behavior. */ | |
680 | ||
681 | if (all_threads.head == all_threads.tail) | |
da6d8c04 | 682 | { |
0d62e5e8 DJ |
683 | if (WIFEXITED (w)) |
684 | { | |
685 | fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w)); | |
686 | *status = 'W'; | |
687 | clear_inferiors (); | |
688 | return ((unsigned char) WEXITSTATUS (w)); | |
689 | } | |
690 | else if (!WIFSTOPPED (w)) | |
691 | { | |
692 | fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w)); | |
693 | clear_inferiors (); | |
694 | *status = 'X'; | |
695 | return ((unsigned char) WTERMSIG (w)); | |
696 | } | |
da6d8c04 | 697 | } |
0d62e5e8 | 698 | else |
da6d8c04 | 699 | { |
0d62e5e8 DJ |
700 | if (!WIFSTOPPED (w)) |
701 | goto retry; | |
da6d8c04 DJ |
702 | } |
703 | ||
da6d8c04 DJ |
704 | *status = 'T'; |
705 | return ((unsigned char) WSTOPSIG (w)); | |
706 | } | |
707 | ||
0d62e5e8 DJ |
708 | static void |
709 | send_sigstop (struct inferior_list_entry *entry) | |
710 | { | |
711 | struct process_info *process = (struct process_info *) entry; | |
712 | ||
713 | if (process->stopped) | |
714 | return; | |
715 | ||
716 | /* If we already have a pending stop signal for this process, don't | |
717 | send another. */ | |
718 | if (process->stop_expected) | |
719 | { | |
720 | process->stop_expected = 0; | |
721 | return; | |
722 | } | |
723 | ||
724 | if (debug_threads) | |
725 | fprintf (stderr, "Sending sigstop to process %d\n", process->head.id); | |
726 | ||
727 | kill (process->head.id, SIGSTOP); | |
728 | process->sigstop_sent = 1; | |
729 | } | |
730 | ||
731 | static void | |
732 | wait_for_sigstop (struct inferior_list_entry *entry) | |
733 | { | |
734 | struct process_info *process = (struct process_info *) entry; | |
735 | struct thread_info *saved_inferior, *thread; | |
736 | int wstat, saved_tid; | |
737 | ||
738 | if (process->stopped) | |
739 | return; | |
740 | ||
741 | saved_inferior = current_inferior; | |
742 | saved_tid = ((struct inferior_list_entry *) saved_inferior)->id; | |
743 | thread = (struct thread_info *) find_inferior_id (&all_threads, | |
744 | process->tid); | |
745 | wstat = linux_wait_for_event (thread); | |
746 | ||
747 | /* If we stopped with a non-SIGSTOP signal, save it for later | |
748 | and record the pending SIGSTOP. If the process exited, just | |
749 | return. */ | |
750 | if (WIFSTOPPED (wstat) | |
751 | && WSTOPSIG (wstat) != SIGSTOP) | |
752 | { | |
753 | if (debug_threads) | |
754 | fprintf (stderr, "Stopped with non-sigstop signal\n"); | |
755 | process->status_pending_p = 1; | |
756 | process->status_pending = wstat; | |
757 | process->stop_expected = 1; | |
758 | } | |
759 | ||
760 | if (linux_thread_alive (saved_tid)) | |
761 | current_inferior = saved_inferior; | |
762 | else | |
763 | { | |
764 | if (debug_threads) | |
765 | fprintf (stderr, "Previously current thread died.\n"); | |
766 | ||
767 | /* Set a valid thread as current. */ | |
768 | set_desired_inferior (0); | |
769 | } | |
770 | } | |
771 | ||
772 | static void | |
773 | stop_all_processes (void) | |
774 | { | |
775 | stopping_threads = 1; | |
776 | for_each_inferior (&all_processes, send_sigstop); | |
777 | for_each_inferior (&all_processes, wait_for_sigstop); | |
778 | stopping_threads = 0; | |
779 | } | |
780 | ||
da6d8c04 DJ |
781 | /* Resume execution of the inferior process. |
782 | If STEP is nonzero, single-step it. | |
783 | If SIGNAL is nonzero, give it that signal. */ | |
784 | ||
ce3a066d | 785 | static void |
0d62e5e8 DJ |
786 | linux_resume_one_process (struct inferior_list_entry *entry, |
787 | int step, int signal) | |
da6d8c04 | 788 | { |
0d62e5e8 DJ |
789 | struct process_info *process = (struct process_info *) entry; |
790 | struct thread_info *saved_inferior; | |
791 | ||
792 | if (process->stopped == 0) | |
793 | return; | |
794 | ||
795 | /* If we have pending signals or status, and a new signal, enqueue the | |
796 | signal. Also enqueue the signal if we are waiting to reinsert a | |
797 | breakpoint; it will be picked up again below. */ | |
798 | if (signal != 0 | |
799 | && (process->status_pending_p || process->pending_signals != NULL | |
800 | || process->bp_reinsert != 0)) | |
801 | { | |
802 | struct pending_signals *p_sig; | |
803 | p_sig = malloc (sizeof (*p_sig)); | |
804 | p_sig->prev = process->pending_signals; | |
805 | p_sig->signal = signal; | |
806 | process->pending_signals = p_sig; | |
807 | } | |
808 | ||
e5379b03 | 809 | if (process->status_pending_p && !check_removed_breakpoint (process)) |
0d62e5e8 DJ |
810 | return; |
811 | ||
812 | saved_inferior = current_inferior; | |
813 | current_inferior = get_process_thread (process); | |
814 | ||
815 | if (debug_threads) | |
816 | fprintf (stderr, "Resuming process %d (%s, signal %d, stop %s)\n", inferior_pid, | |
817 | step ? "step" : "continue", signal, | |
818 | process->stop_expected ? "expected" : "not expected"); | |
819 | ||
820 | /* This bit needs some thinking about. If we get a signal that | |
821 | we must report while a single-step reinsert is still pending, | |
822 | we often end up resuming the thread. It might be better to | |
823 | (ew) allow a stack of pending events; then we could be sure that | |
824 | the reinsert happened right away and not lose any signals. | |
825 | ||
826 | Making this stack would also shrink the window in which breakpoints are | |
827 | uninserted (see comment in linux_wait_for_process) but not enough for | |
828 | complete correctness, so it won't solve that problem. It may be | |
829 | worthwhile just to solve this one, however. */ | |
830 | if (process->bp_reinsert != 0) | |
831 | { | |
832 | if (debug_threads) | |
833 | fprintf (stderr, " pending reinsert at %08lx", (long)process->bp_reinsert); | |
834 | if (step == 0) | |
835 | fprintf (stderr, "BAD - reinserting but not stepping.\n"); | |
836 | step = 1; | |
837 | ||
838 | /* Postpone any pending signal. It was enqueued above. */ | |
839 | signal = 0; | |
840 | } | |
841 | ||
842 | check_removed_breakpoint (process); | |
843 | ||
aa691b87 | 844 | if (debug_threads && the_low_target.get_pc != NULL) |
0d62e5e8 DJ |
845 | { |
846 | fprintf (stderr, " "); | |
847 | (long) (*the_low_target.get_pc) (); | |
848 | } | |
849 | ||
850 | /* If we have pending signals, consume one unless we are trying to reinsert | |
851 | a breakpoint. */ | |
852 | if (process->pending_signals != NULL && process->bp_reinsert == 0) | |
853 | { | |
854 | struct pending_signals **p_sig; | |
855 | ||
856 | p_sig = &process->pending_signals; | |
857 | while ((*p_sig)->prev != NULL) | |
858 | p_sig = &(*p_sig)->prev; | |
859 | ||
860 | signal = (*p_sig)->signal; | |
861 | free (*p_sig); | |
862 | *p_sig = NULL; | |
863 | } | |
864 | ||
865 | regcache_invalidate_one ((struct inferior_list_entry *) | |
866 | get_process_thread (process)); | |
da6d8c04 | 867 | errno = 0; |
0d62e5e8 DJ |
868 | process->stopped = 0; |
869 | process->stepping = step; | |
870 | ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, process->lwpid, 0, signal); | |
871 | ||
872 | current_inferior = saved_inferior; | |
da6d8c04 DJ |
873 | if (errno) |
874 | perror_with_name ("ptrace"); | |
875 | } | |
876 | ||
64386c31 DJ |
877 | static struct thread_resume *resume_ptr; |
878 | ||
879 | /* This function is called once per thread. We look up the thread | |
5544ad89 DJ |
880 | in RESUME_PTR, and mark the thread with a pointer to the appropriate |
881 | resume request. | |
882 | ||
883 | This algorithm is O(threads * resume elements), but resume elements | |
884 | is small (and will remain small at least until GDB supports thread | |
885 | suspension). */ | |
0d62e5e8 | 886 | static void |
5544ad89 | 887 | linux_set_resume_request (struct inferior_list_entry *entry) |
0d62e5e8 DJ |
888 | { |
889 | struct process_info *process; | |
64386c31 | 890 | struct thread_info *thread; |
5544ad89 | 891 | int ndx; |
64386c31 DJ |
892 | |
893 | thread = (struct thread_info *) entry; | |
894 | process = get_thread_process (thread); | |
895 | ||
896 | ndx = 0; | |
897 | while (resume_ptr[ndx].thread != -1 && resume_ptr[ndx].thread != entry->id) | |
898 | ndx++; | |
899 | ||
5544ad89 DJ |
900 | process->resume = &resume_ptr[ndx]; |
901 | } | |
902 | ||
903 | /* This function is called once per thread. We check the thread's resume | |
904 | request, which will tell us whether to resume, step, or leave the thread | |
905 | stopped; and what signal, if any, it should be sent. For threads which | |
906 | we aren't explicitly told otherwise, we preserve the stepping flag; this | |
907 | is used for stepping over gdbserver-placed breakpoints. */ | |
908 | ||
909 | static void | |
910 | linux_continue_one_thread (struct inferior_list_entry *entry) | |
911 | { | |
912 | struct process_info *process; | |
913 | struct thread_info *thread; | |
914 | int step; | |
915 | ||
916 | thread = (struct thread_info *) entry; | |
917 | process = get_thread_process (thread); | |
918 | ||
919 | if (process->resume->leave_stopped) | |
64386c31 DJ |
920 | return; |
921 | ||
5544ad89 DJ |
922 | if (process->resume->thread == -1) |
923 | step = process->stepping || process->resume->step; | |
64386c31 | 924 | else |
5544ad89 DJ |
925 | step = process->resume->step; |
926 | ||
927 | linux_resume_one_process (&process->head, step, process->resume->sig); | |
c6ecbae5 | 928 | |
5544ad89 DJ |
929 | process->resume = NULL; |
930 | } | |
931 | ||
932 | /* This function is called once per thread. We check the thread's resume | |
933 | request, which will tell us whether to resume, step, or leave the thread | |
934 | stopped; and what signal, if any, it should be sent. We queue any needed | |
935 | signals, since we won't actually resume. We already have a pending event | |
936 | to report, so we don't need to preserve any step requests; they should | |
937 | be re-issued if necessary. */ | |
938 | ||
939 | static void | |
940 | linux_queue_one_thread (struct inferior_list_entry *entry) | |
941 | { | |
942 | struct process_info *process; | |
943 | struct thread_info *thread; | |
944 | ||
945 | thread = (struct thread_info *) entry; | |
946 | process = get_thread_process (thread); | |
947 | ||
948 | if (process->resume->leave_stopped) | |
949 | return; | |
950 | ||
951 | /* If we have a new signal, enqueue the signal. */ | |
952 | if (process->resume->sig != 0) | |
953 | { | |
954 | struct pending_signals *p_sig; | |
955 | p_sig = malloc (sizeof (*p_sig)); | |
956 | p_sig->prev = process->pending_signals; | |
957 | p_sig->signal = process->resume->sig; | |
958 | process->pending_signals = p_sig; | |
959 | } | |
960 | ||
961 | process->resume = NULL; | |
962 | } | |
963 | ||
964 | /* Set DUMMY if this process has an interesting status pending. */ | |
965 | static int | |
966 | resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p) | |
967 | { | |
968 | struct process_info *process = (struct process_info *) entry; | |
969 | ||
970 | /* Processes which will not be resumed are not interesting, because | |
971 | we might not wait for them next time through linux_wait. */ | |
972 | if (process->resume->leave_stopped) | |
973 | return 0; | |
974 | ||
975 | /* If this thread has a removed breakpoint, we won't have any | |
976 | events to report later, so check now. check_removed_breakpoint | |
977 | may clear status_pending_p. We avoid calling check_removed_breakpoint | |
978 | for any thread that we are not otherwise going to resume - this | |
979 | lets us preserve stopped status when two threads hit a breakpoint. | |
980 | GDB removes the breakpoint to single-step a particular thread | |
981 | past it, then re-inserts it and resumes all threads. We want | |
982 | to report the second thread without resuming it in the interim. */ | |
983 | if (process->status_pending_p) | |
984 | check_removed_breakpoint (process); | |
985 | ||
986 | if (process->status_pending_p) | |
987 | * (int *) flag_p = 1; | |
988 | ||
989 | return 0; | |
0d62e5e8 DJ |
990 | } |
991 | ||
992 | static void | |
64386c31 | 993 | linux_resume (struct thread_resume *resume_info) |
0d62e5e8 | 994 | { |
5544ad89 | 995 | int pending_flag; |
c6ecbae5 | 996 | |
5544ad89 | 997 | /* Yes, the use of a global here is rather ugly. */ |
64386c31 | 998 | resume_ptr = resume_info; |
5544ad89 DJ |
999 | |
1000 | for_each_inferior (&all_threads, linux_set_resume_request); | |
1001 | ||
1002 | /* If there is a thread which would otherwise be resumed, which | |
1003 | has a pending status, then don't resume any threads - we can just | |
1004 | report the pending status. Make sure to queue any signals | |
1005 | that would otherwise be sent. */ | |
1006 | pending_flag = 0; | |
1007 | find_inferior (&all_processes, resume_status_pending_p, &pending_flag); | |
1008 | ||
1009 | if (debug_threads) | |
1010 | { | |
1011 | if (pending_flag) | |
1012 | fprintf (stderr, "Not resuming, pending status\n"); | |
1013 | else | |
1014 | fprintf (stderr, "Resuming, no pending status\n"); | |
1015 | } | |
1016 | ||
1017 | if (pending_flag) | |
1018 | for_each_inferior (&all_threads, linux_queue_one_thread); | |
1019 | else | |
62ea82f5 DJ |
1020 | { |
1021 | block_async_io (); | |
1022 | enable_async_io (); | |
1023 | for_each_inferior (&all_threads, linux_continue_one_thread); | |
1024 | } | |
0d62e5e8 DJ |
1025 | } |
1026 | ||
1027 | #ifdef HAVE_LINUX_USRREGS | |
da6d8c04 DJ |
1028 | |
1029 | int | |
0a30fbc4 | 1030 | register_addr (int regnum) |
da6d8c04 DJ |
1031 | { |
1032 | int addr; | |
1033 | ||
2ec06d2e | 1034 | if (regnum < 0 || regnum >= the_low_target.num_regs) |
da6d8c04 DJ |
1035 | error ("Invalid register number %d.", regnum); |
1036 | ||
2ec06d2e | 1037 | addr = the_low_target.regmap[regnum]; |
da6d8c04 DJ |
1038 | |
1039 | return addr; | |
1040 | } | |
1041 | ||
58caa3dc | 1042 | /* Fetch one register. */ |
da6d8c04 DJ |
1043 | static void |
1044 | fetch_register (int regno) | |
1045 | { | |
1046 | CORE_ADDR regaddr; | |
1047 | register int i; | |
0d62e5e8 | 1048 | char *buf; |
da6d8c04 | 1049 | |
2ec06d2e | 1050 | if (regno >= the_low_target.num_regs) |
0a30fbc4 | 1051 | return; |
2ec06d2e | 1052 | if ((*the_low_target.cannot_fetch_register) (regno)) |
0a30fbc4 | 1053 | return; |
da6d8c04 | 1054 | |
0a30fbc4 DJ |
1055 | regaddr = register_addr (regno); |
1056 | if (regaddr == -1) | |
1057 | return; | |
0d62e5e8 DJ |
1058 | buf = alloca (register_size (regno)); |
1059 | for (i = 0; i < register_size (regno); i += sizeof (PTRACE_XFER_TYPE)) | |
da6d8c04 DJ |
1060 | { |
1061 | errno = 0; | |
0d62e5e8 | 1062 | *(PTRACE_XFER_TYPE *) (buf + i) = |
da6d8c04 DJ |
1063 | ptrace (PTRACE_PEEKUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, 0); |
1064 | regaddr += sizeof (PTRACE_XFER_TYPE); | |
1065 | if (errno != 0) | |
1066 | { | |
1067 | /* Warning, not error, in case we are attached; sometimes the | |
1068 | kernel doesn't let us at the registers. */ | |
1069 | char *err = strerror (errno); | |
1070 | char *msg = alloca (strlen (err) + 128); | |
1071 | sprintf (msg, "reading register %d: %s", regno, err); | |
1072 | error (msg); | |
1073 | goto error_exit; | |
1074 | } | |
1075 | } | |
0d62e5e8 DJ |
1076 | supply_register (regno, buf); |
1077 | ||
da6d8c04 DJ |
1078 | error_exit:; |
1079 | } | |
1080 | ||
1081 | /* Fetch all registers, or just one, from the child process. */ | |
58caa3dc DJ |
1082 | static void |
1083 | usr_fetch_inferior_registers (int regno) | |
da6d8c04 DJ |
1084 | { |
1085 | if (regno == -1 || regno == 0) | |
2ec06d2e | 1086 | for (regno = 0; regno < the_low_target.num_regs; regno++) |
da6d8c04 DJ |
1087 | fetch_register (regno); |
1088 | else | |
1089 | fetch_register (regno); | |
1090 | } | |
1091 | ||
1092 | /* Store our register values back into the inferior. | |
1093 | If REGNO is -1, do this for all registers. | |
1094 | Otherwise, REGNO specifies which register (so we can save time). */ | |
58caa3dc DJ |
1095 | static void |
1096 | usr_store_inferior_registers (int regno) | |
da6d8c04 DJ |
1097 | { |
1098 | CORE_ADDR regaddr; | |
1099 | int i; | |
0d62e5e8 | 1100 | char *buf; |
da6d8c04 DJ |
1101 | |
1102 | if (regno >= 0) | |
1103 | { | |
2ec06d2e | 1104 | if (regno >= the_low_target.num_regs) |
0a30fbc4 DJ |
1105 | return; |
1106 | ||
bc1e36ca | 1107 | if ((*the_low_target.cannot_store_register) (regno) == 1) |
0a30fbc4 DJ |
1108 | return; |
1109 | ||
1110 | regaddr = register_addr (regno); | |
1111 | if (regaddr == -1) | |
da6d8c04 | 1112 | return; |
da6d8c04 | 1113 | errno = 0; |
0d62e5e8 DJ |
1114 | buf = alloca (register_size (regno)); |
1115 | collect_register (regno, buf); | |
1116 | for (i = 0; i < register_size (regno); i += sizeof (PTRACE_XFER_TYPE)) | |
da6d8c04 | 1117 | { |
0a30fbc4 DJ |
1118 | errno = 0; |
1119 | ptrace (PTRACE_POKEUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, | |
2ff29de4 | 1120 | *(PTRACE_XFER_TYPE *) (buf + i)); |
da6d8c04 DJ |
1121 | if (errno != 0) |
1122 | { | |
bc1e36ca DJ |
1123 | if ((*the_low_target.cannot_store_register) (regno) == 0) |
1124 | { | |
1125 | char *err = strerror (errno); | |
1126 | char *msg = alloca (strlen (err) + 128); | |
1127 | sprintf (msg, "writing register %d: %s", | |
1128 | regno, err); | |
1129 | error (msg); | |
1130 | return; | |
1131 | } | |
da6d8c04 | 1132 | } |
2ff29de4 | 1133 | regaddr += sizeof (PTRACE_XFER_TYPE); |
da6d8c04 | 1134 | } |
da6d8c04 DJ |
1135 | } |
1136 | else | |
2ec06d2e | 1137 | for (regno = 0; regno < the_low_target.num_regs; regno++) |
0d62e5e8 | 1138 | usr_store_inferior_registers (regno); |
da6d8c04 | 1139 | } |
58caa3dc DJ |
1140 | #endif /* HAVE_LINUX_USRREGS */ |
1141 | ||
1142 | ||
1143 | ||
1144 | #ifdef HAVE_LINUX_REGSETS | |
1145 | ||
1146 | static int | |
0d62e5e8 | 1147 | regsets_fetch_inferior_registers () |
58caa3dc DJ |
1148 | { |
1149 | struct regset_info *regset; | |
1150 | ||
1151 | regset = target_regsets; | |
1152 | ||
1153 | while (regset->size >= 0) | |
1154 | { | |
1155 | void *buf; | |
1156 | int res; | |
1157 | ||
1158 | if (regset->size == 0) | |
1159 | { | |
1160 | regset ++; | |
1161 | continue; | |
1162 | } | |
1163 | ||
1164 | buf = malloc (regset->size); | |
d06f167a | 1165 | res = ptrace (regset->get_request, inferior_pid, 0, buf); |
58caa3dc DJ |
1166 | if (res < 0) |
1167 | { | |
1168 | if (errno == EIO) | |
1169 | { | |
1170 | /* If we get EIO on the first regset, do not try regsets again. | |
1171 | If we get EIO on a later regset, disable that regset. */ | |
1172 | if (regset == target_regsets) | |
1173 | { | |
1174 | use_regsets_p = 0; | |
1175 | return -1; | |
1176 | } | |
1177 | else | |
1178 | { | |
1179 | regset->size = 0; | |
1180 | continue; | |
1181 | } | |
1182 | } | |
1183 | else | |
1184 | { | |
0d62e5e8 DJ |
1185 | char s[256]; |
1186 | sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d", | |
1187 | inferior_pid); | |
1188 | perror (s); | |
58caa3dc DJ |
1189 | } |
1190 | } | |
1191 | regset->store_function (buf); | |
1192 | regset ++; | |
1193 | } | |
ce3a066d | 1194 | return 0; |
58caa3dc DJ |
1195 | } |
1196 | ||
1197 | static int | |
0d62e5e8 | 1198 | regsets_store_inferior_registers () |
58caa3dc DJ |
1199 | { |
1200 | struct regset_info *regset; | |
1201 | ||
1202 | regset = target_regsets; | |
1203 | ||
1204 | while (regset->size >= 0) | |
1205 | { | |
1206 | void *buf; | |
1207 | int res; | |
1208 | ||
1209 | if (regset->size == 0) | |
1210 | { | |
1211 | regset ++; | |
1212 | continue; | |
1213 | } | |
1214 | ||
1215 | buf = malloc (regset->size); | |
1216 | regset->fill_function (buf); | |
d06f167a | 1217 | res = ptrace (regset->set_request, inferior_pid, 0, buf); |
58caa3dc DJ |
1218 | if (res < 0) |
1219 | { | |
1220 | if (errno == EIO) | |
1221 | { | |
1222 | /* If we get EIO on the first regset, do not try regsets again. | |
1223 | If we get EIO on a later regset, disable that regset. */ | |
1224 | if (regset == target_regsets) | |
1225 | { | |
1226 | use_regsets_p = 0; | |
1227 | return -1; | |
1228 | } | |
1229 | else | |
1230 | { | |
1231 | regset->size = 0; | |
1232 | continue; | |
1233 | } | |
1234 | } | |
1235 | else | |
1236 | { | |
ce3a066d | 1237 | perror ("Warning: ptrace(regsets_store_inferior_registers)"); |
58caa3dc DJ |
1238 | } |
1239 | } | |
1240 | regset ++; | |
09ec9b38 | 1241 | free (buf); |
58caa3dc | 1242 | } |
ce3a066d | 1243 | return 0; |
58caa3dc DJ |
1244 | } |
1245 | ||
1246 | #endif /* HAVE_LINUX_REGSETS */ | |
1247 | ||
1248 | ||
1249 | void | |
ce3a066d | 1250 | linux_fetch_registers (int regno) |
58caa3dc DJ |
1251 | { |
1252 | #ifdef HAVE_LINUX_REGSETS | |
1253 | if (use_regsets_p) | |
1254 | { | |
1255 | if (regsets_fetch_inferior_registers () == 0) | |
1256 | return; | |
1257 | } | |
1258 | #endif | |
1259 | #ifdef HAVE_LINUX_USRREGS | |
1260 | usr_fetch_inferior_registers (regno); | |
1261 | #endif | |
1262 | } | |
1263 | ||
1264 | void | |
ce3a066d | 1265 | linux_store_registers (int regno) |
58caa3dc DJ |
1266 | { |
1267 | #ifdef HAVE_LINUX_REGSETS | |
1268 | if (use_regsets_p) | |
1269 | { | |
1270 | if (regsets_store_inferior_registers () == 0) | |
1271 | return; | |
1272 | } | |
1273 | #endif | |
1274 | #ifdef HAVE_LINUX_USRREGS | |
1275 | usr_store_inferior_registers (regno); | |
1276 | #endif | |
1277 | } | |
1278 | ||
da6d8c04 | 1279 | |
da6d8c04 DJ |
1280 | /* Copy LEN bytes from inferior's memory starting at MEMADDR |
1281 | to debugger memory starting at MYADDR. */ | |
1282 | ||
c3e735a6 | 1283 | static int |
ce3a066d | 1284 | linux_read_memory (CORE_ADDR memaddr, char *myaddr, int len) |
da6d8c04 DJ |
1285 | { |
1286 | register int i; | |
1287 | /* Round starting address down to longword boundary. */ | |
1288 | register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
1289 | /* Round ending address up; get number of longwords that makes. */ | |
aa691b87 RM |
1290 | register int count |
1291 | = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) | |
da6d8c04 DJ |
1292 | / sizeof (PTRACE_XFER_TYPE); |
1293 | /* Allocate buffer of that many longwords. */ | |
aa691b87 | 1294 | register PTRACE_XFER_TYPE *buffer |
da6d8c04 DJ |
1295 | = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE)); |
1296 | ||
1297 | /* Read all the longwords */ | |
1298 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
1299 | { | |
c3e735a6 | 1300 | errno = 0; |
d844cde6 | 1301 | buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, 0); |
c3e735a6 DJ |
1302 | if (errno) |
1303 | return errno; | |
da6d8c04 DJ |
1304 | } |
1305 | ||
1306 | /* Copy appropriate bytes out of the buffer. */ | |
1307 | memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), len); | |
c3e735a6 DJ |
1308 | |
1309 | return 0; | |
da6d8c04 DJ |
1310 | } |
1311 | ||
1312 | /* Copy LEN bytes of data from debugger memory at MYADDR | |
1313 | to inferior's memory at MEMADDR. | |
1314 | On failure (cannot write the inferior) | |
1315 | returns the value of errno. */ | |
1316 | ||
ce3a066d | 1317 | static int |
611cb4a5 | 1318 | linux_write_memory (CORE_ADDR memaddr, const char *myaddr, int len) |
da6d8c04 DJ |
1319 | { |
1320 | register int i; | |
1321 | /* Round starting address down to longword boundary. */ | |
1322 | register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
1323 | /* Round ending address up; get number of longwords that makes. */ | |
1324 | register int count | |
1325 | = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) / sizeof (PTRACE_XFER_TYPE); | |
1326 | /* Allocate buffer of that many longwords. */ | |
1327 | register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE)); | |
1328 | extern int errno; | |
1329 | ||
0d62e5e8 DJ |
1330 | if (debug_threads) |
1331 | { | |
1332 | fprintf (stderr, "Writing %02x to %08lx\n", (unsigned)myaddr[0], (long)memaddr); | |
1333 | } | |
1334 | ||
da6d8c04 DJ |
1335 | /* Fill start and end extra bytes of buffer with existing memory data. */ |
1336 | ||
d844cde6 DJ |
1337 | buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid, |
1338 | (PTRACE_ARG3_TYPE) addr, 0); | |
da6d8c04 DJ |
1339 | |
1340 | if (count > 1) | |
1341 | { | |
1342 | buffer[count - 1] | |
1343 | = ptrace (PTRACE_PEEKTEXT, inferior_pid, | |
d844cde6 DJ |
1344 | (PTRACE_ARG3_TYPE) (addr + (count - 1) |
1345 | * sizeof (PTRACE_XFER_TYPE)), | |
1346 | 0); | |
da6d8c04 DJ |
1347 | } |
1348 | ||
1349 | /* Copy data to be written over corresponding part of buffer */ | |
1350 | ||
1351 | memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), myaddr, len); | |
1352 | ||
1353 | /* Write the entire buffer. */ | |
1354 | ||
1355 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
1356 | { | |
1357 | errno = 0; | |
d844cde6 | 1358 | ptrace (PTRACE_POKETEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, buffer[i]); |
da6d8c04 DJ |
1359 | if (errno) |
1360 | return errno; | |
1361 | } | |
1362 | ||
1363 | return 0; | |
1364 | } | |
2f2893d9 DJ |
1365 | |
1366 | static void | |
1367 | linux_look_up_symbols (void) | |
1368 | { | |
0d62e5e8 DJ |
1369 | #ifdef USE_THREAD_DB |
1370 | if (using_threads) | |
1371 | return; | |
1372 | ||
1373 | using_threads = thread_db_init (); | |
1374 | #endif | |
1375 | } | |
1376 | ||
e5379b03 DJ |
1377 | static void |
1378 | linux_send_signal (int signum) | |
1379 | { | |
1380 | extern int signal_pid; | |
1381 | ||
1382 | if (cont_thread > 0) | |
1383 | { | |
1384 | struct process_info *process; | |
1385 | ||
1386 | process = get_thread_process (current_inferior); | |
1387 | kill (process->lwpid, signum); | |
1388 | } | |
1389 | else | |
1390 | kill (signal_pid, signum); | |
1391 | } | |
1392 | ||
aa691b87 RM |
1393 | /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET |
1394 | to debugger memory starting at MYADDR. */ | |
1395 | ||
1396 | static int | |
1397 | linux_read_auxv (CORE_ADDR offset, char *myaddr, unsigned int len) | |
1398 | { | |
1399 | char filename[PATH_MAX]; | |
1400 | int fd, n; | |
1401 | ||
1402 | snprintf (filename, sizeof filename, "/proc/%d/auxv", inferior_pid); | |
1403 | ||
1404 | fd = open (filename, O_RDONLY); | |
1405 | if (fd < 0) | |
1406 | return -1; | |
1407 | ||
1408 | if (offset != (CORE_ADDR) 0 | |
1409 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
1410 | n = -1; | |
1411 | else | |
1412 | n = read (fd, myaddr, len); | |
1413 | ||
1414 | close (fd); | |
1415 | ||
1416 | return n; | |
1417 | } | |
1418 | ||
da6d8c04 | 1419 | \f |
ce3a066d DJ |
1420 | static struct target_ops linux_target_ops = { |
1421 | linux_create_inferior, | |
1422 | linux_attach, | |
1423 | linux_kill, | |
6ad8ae5c | 1424 | linux_detach, |
ce3a066d DJ |
1425 | linux_thread_alive, |
1426 | linux_resume, | |
1427 | linux_wait, | |
1428 | linux_fetch_registers, | |
1429 | linux_store_registers, | |
1430 | linux_read_memory, | |
1431 | linux_write_memory, | |
2f2893d9 | 1432 | linux_look_up_symbols, |
e5379b03 | 1433 | linux_send_signal, |
aa691b87 | 1434 | linux_read_auxv, |
ce3a066d DJ |
1435 | }; |
1436 | ||
0d62e5e8 DJ |
1437 | static void |
1438 | linux_init_signals () | |
1439 | { | |
1440 | /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads | |
1441 | to find what the cancel signal actually is. */ | |
254787d4 | 1442 | signal (__SIGRTMIN+1, SIG_IGN); |
0d62e5e8 DJ |
1443 | } |
1444 | ||
da6d8c04 DJ |
1445 | void |
1446 | initialize_low (void) | |
1447 | { | |
0d62e5e8 | 1448 | using_threads = 0; |
ce3a066d | 1449 | set_target_ops (&linux_target_ops); |
611cb4a5 DJ |
1450 | set_breakpoint_data (the_low_target.breakpoint, |
1451 | the_low_target.breakpoint_len); | |
0a30fbc4 | 1452 | init_registers (); |
0d62e5e8 | 1453 | linux_init_signals (); |
da6d8c04 | 1454 | } |