]>
Commit | Line | Data |
---|---|---|
da6d8c04 | 1 | /* Low level interface to ptrace, for the remote server for GDB. |
545587ee | 2 | Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, |
6aba47ca | 3 | 2006, 2007 Free Software Foundation, Inc. |
da6d8c04 DJ |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
da6d8c04 DJ |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
da6d8c04 DJ |
19 | |
20 | #include "server.h" | |
58caa3dc | 21 | #include "linux-low.h" |
da6d8c04 | 22 | |
58caa3dc | 23 | #include <sys/wait.h> |
da6d8c04 DJ |
24 | #include <stdio.h> |
25 | #include <sys/param.h> | |
26 | #include <sys/dir.h> | |
27 | #include <sys/ptrace.h> | |
28 | #include <sys/user.h> | |
29 | #include <signal.h> | |
30 | #include <sys/ioctl.h> | |
31 | #include <fcntl.h> | |
d07c63e7 | 32 | #include <string.h> |
0a30fbc4 DJ |
33 | #include <stdlib.h> |
34 | #include <unistd.h> | |
fa6a77dc | 35 | #include <errno.h> |
fd500816 | 36 | #include <sys/syscall.h> |
da6d8c04 | 37 | |
32ca6d61 DJ |
38 | #ifndef PTRACE_GETSIGINFO |
39 | # define PTRACE_GETSIGINFO 0x4202 | |
40 | # define PTRACE_SETSIGINFO 0x4203 | |
41 | #endif | |
42 | ||
fd462a61 DJ |
43 | #ifndef O_LARGEFILE |
44 | #define O_LARGEFILE 0 | |
45 | #endif | |
46 | ||
24a09b5f DJ |
47 | /* If the system headers did not provide the constants, hard-code the normal |
48 | values. */ | |
49 | #ifndef PTRACE_EVENT_FORK | |
50 | ||
51 | #define PTRACE_SETOPTIONS 0x4200 | |
52 | #define PTRACE_GETEVENTMSG 0x4201 | |
53 | ||
54 | /* options set using PTRACE_SETOPTIONS */ | |
55 | #define PTRACE_O_TRACESYSGOOD 0x00000001 | |
56 | #define PTRACE_O_TRACEFORK 0x00000002 | |
57 | #define PTRACE_O_TRACEVFORK 0x00000004 | |
58 | #define PTRACE_O_TRACECLONE 0x00000008 | |
59 | #define PTRACE_O_TRACEEXEC 0x00000010 | |
60 | #define PTRACE_O_TRACEVFORKDONE 0x00000020 | |
61 | #define PTRACE_O_TRACEEXIT 0x00000040 | |
62 | ||
63 | /* Wait extended result codes for the above trace options. */ | |
64 | #define PTRACE_EVENT_FORK 1 | |
65 | #define PTRACE_EVENT_VFORK 2 | |
66 | #define PTRACE_EVENT_CLONE 3 | |
67 | #define PTRACE_EVENT_EXEC 4 | |
68 | #define PTRACE_EVENT_VFORK_DONE 5 | |
69 | #define PTRACE_EVENT_EXIT 6 | |
70 | ||
71 | #endif /* PTRACE_EVENT_FORK */ | |
72 | ||
73 | /* We can't always assume that this flag is available, but all systems | |
74 | with the ptrace event handlers also have __WALL, so it's safe to use | |
75 | in some contexts. */ | |
76 | #ifndef __WALL | |
77 | #define __WALL 0x40000000 /* Wait for any child. */ | |
78 | #endif | |
79 | ||
42c81e2a DJ |
80 | #ifdef __UCLIBC__ |
81 | #if !(defined(__UCLIBC_HAS_MMU__) || defined(__ARCH_HAS_MMU__)) | |
82 | #define HAS_NOMMU | |
83 | #endif | |
84 | #endif | |
85 | ||
24a09b5f DJ |
86 | /* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol |
87 | representation of the thread ID. | |
611cb4a5 | 88 | |
0d62e5e8 DJ |
89 | ``all_processes'' is keyed by the process ID - which on Linux is (presently) |
90 | the same as the LWP ID. */ | |
91 | ||
92 | struct inferior_list all_processes; | |
93 | ||
24a09b5f DJ |
94 | /* A list of all unknown processes which receive stop signals. Some other |
95 | process will presumably claim each of these as forked children | |
96 | momentarily. */ | |
97 | ||
98 | struct inferior_list stopped_pids; | |
99 | ||
0d62e5e8 DJ |
100 | /* FIXME this is a bit of a hack, and could be removed. */ |
101 | int stopping_threads; | |
102 | ||
103 | /* FIXME make into a target method? */ | |
24a09b5f DJ |
104 | int using_threads = 1; |
105 | static int thread_db_active; | |
106 | ||
107 | static int must_set_ptrace_flags; | |
0d62e5e8 DJ |
108 | |
109 | static void linux_resume_one_process (struct inferior_list_entry *entry, | |
32ca6d61 | 110 | int step, int signal, siginfo_t *info); |
64386c31 | 111 | static void linux_resume (struct thread_resume *resume_info); |
0d62e5e8 DJ |
112 | static void stop_all_processes (void); |
113 | static int linux_wait_for_event (struct thread_info *child); | |
ae13219e | 114 | static int check_removed_breakpoint (struct process_info *event_child); |
24a09b5f | 115 | static void *add_process (unsigned long pid); |
0d62e5e8 DJ |
116 | |
117 | struct pending_signals | |
118 | { | |
119 | int signal; | |
32ca6d61 | 120 | siginfo_t info; |
0d62e5e8 DJ |
121 | struct pending_signals *prev; |
122 | }; | |
611cb4a5 | 123 | |
d844cde6 | 124 | #define PTRACE_ARG3_TYPE long |
c6ecbae5 | 125 | #define PTRACE_XFER_TYPE long |
da6d8c04 | 126 | |
58caa3dc DJ |
127 | #ifdef HAVE_LINUX_REGSETS |
128 | static int use_regsets_p = 1; | |
129 | #endif | |
130 | ||
0d62e5e8 DJ |
131 | #define pid_of(proc) ((proc)->head.id) |
132 | ||
133 | /* FIXME: Delete eventually. */ | |
134 | #define inferior_pid (pid_of (get_thread_process (current_inferior))) | |
135 | ||
24a09b5f DJ |
136 | static void |
137 | handle_extended_wait (struct process_info *event_child, int wstat) | |
138 | { | |
139 | int event = wstat >> 16; | |
140 | struct process_info *new_process; | |
141 | ||
142 | if (event == PTRACE_EVENT_CLONE) | |
143 | { | |
144 | unsigned long new_pid; | |
145 | int ret, status; | |
146 | ||
147 | ptrace (PTRACE_GETEVENTMSG, inferior_pid, 0, &new_pid); | |
148 | ||
149 | /* If we haven't already seen the new PID stop, wait for it now. */ | |
150 | if (! pull_pid_from_list (&stopped_pids, new_pid)) | |
151 | { | |
152 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
153 | hits the SIGSTOP, but we're already attached. */ | |
154 | ||
155 | do { | |
156 | ret = waitpid (new_pid, &status, __WALL); | |
157 | } while (ret == -1 && errno == EINTR); | |
158 | ||
159 | if (ret == -1) | |
160 | perror_with_name ("waiting for new child"); | |
161 | else if (ret != new_pid) | |
162 | warning ("wait returned unexpected PID %d", ret); | |
da5898ce | 163 | else if (!WIFSTOPPED (status)) |
24a09b5f DJ |
164 | warning ("wait returned unexpected status 0x%x", status); |
165 | } | |
166 | ||
167 | ptrace (PTRACE_SETOPTIONS, new_pid, 0, PTRACE_O_TRACECLONE); | |
168 | ||
169 | new_process = (struct process_info *) add_process (new_pid); | |
170 | add_thread (new_pid, new_process, new_pid); | |
171 | new_thread_notify (thread_id_to_gdb_id (new_process->lwpid)); | |
172 | ||
da5898ce DJ |
173 | /* Normally we will get the pending SIGSTOP. But in some cases |
174 | we might get another signal delivered to the group first. | |
175 | If we do, be sure not to lose it. */ | |
176 | if (WSTOPSIG (status) == SIGSTOP) | |
177 | { | |
178 | if (stopping_threads) | |
179 | new_process->stopped = 1; | |
180 | else | |
181 | ptrace (PTRACE_CONT, new_pid, 0, 0); | |
182 | } | |
24a09b5f | 183 | else |
da5898ce DJ |
184 | { |
185 | new_process->stop_expected = 1; | |
186 | if (stopping_threads) | |
187 | { | |
188 | new_process->stopped = 1; | |
189 | new_process->status_pending_p = 1; | |
190 | new_process->status_pending = status; | |
191 | } | |
192 | else | |
193 | /* Pass the signal on. This is what GDB does - except | |
194 | shouldn't we really report it instead? */ | |
195 | ptrace (PTRACE_CONT, new_pid, 0, WSTOPSIG (status)); | |
196 | } | |
24a09b5f DJ |
197 | |
198 | /* Always resume the current thread. If we are stopping | |
199 | threads, it will have a pending SIGSTOP; we may as well | |
200 | collect it now. */ | |
201 | linux_resume_one_process (&event_child->head, | |
202 | event_child->stepping, 0, NULL); | |
203 | } | |
204 | } | |
205 | ||
0d62e5e8 DJ |
206 | /* This function should only be called if the process got a SIGTRAP. |
207 | The SIGTRAP could mean several things. | |
208 | ||
209 | On i386, where decr_pc_after_break is non-zero: | |
210 | If we were single-stepping this process using PTRACE_SINGLESTEP, | |
211 | we will get only the one SIGTRAP (even if the instruction we | |
212 | stepped over was a breakpoint). The value of $eip will be the | |
213 | next instruction. | |
214 | If we continue the process using PTRACE_CONT, we will get a | |
215 | SIGTRAP when we hit a breakpoint. The value of $eip will be | |
216 | the instruction after the breakpoint (i.e. needs to be | |
217 | decremented). If we report the SIGTRAP to GDB, we must also | |
218 | report the undecremented PC. If we cancel the SIGTRAP, we | |
219 | must resume at the decremented PC. | |
220 | ||
221 | (Presumably, not yet tested) On a non-decr_pc_after_break machine | |
222 | with hardware or kernel single-step: | |
223 | If we single-step over a breakpoint instruction, our PC will | |
224 | point at the following instruction. If we continue and hit a | |
225 | breakpoint instruction, our PC will point at the breakpoint | |
226 | instruction. */ | |
227 | ||
228 | static CORE_ADDR | |
229 | get_stop_pc (void) | |
230 | { | |
231 | CORE_ADDR stop_pc = (*the_low_target.get_pc) (); | |
232 | ||
233 | if (get_thread_process (current_inferior)->stepping) | |
234 | return stop_pc; | |
235 | else | |
236 | return stop_pc - the_low_target.decr_pc_after_break; | |
237 | } | |
ce3a066d | 238 | |
0d62e5e8 | 239 | static void * |
a1928bad | 240 | add_process (unsigned long pid) |
611cb4a5 | 241 | { |
0d62e5e8 DJ |
242 | struct process_info *process; |
243 | ||
244 | process = (struct process_info *) malloc (sizeof (*process)); | |
245 | memset (process, 0, sizeof (*process)); | |
246 | ||
247 | process->head.id = pid; | |
0d62e5e8 DJ |
248 | process->lwpid = pid; |
249 | ||
250 | add_inferior_to_list (&all_processes, &process->head); | |
251 | ||
252 | return process; | |
253 | } | |
611cb4a5 | 254 | |
da6d8c04 DJ |
255 | /* Start an inferior process and returns its pid. |
256 | ALLARGS is a vector of program-name and args. */ | |
257 | ||
ce3a066d DJ |
258 | static int |
259 | linux_create_inferior (char *program, char **allargs) | |
da6d8c04 | 260 | { |
0d62e5e8 | 261 | void *new_process; |
da6d8c04 DJ |
262 | int pid; |
263 | ||
42c81e2a | 264 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) |
52fb6437 NS |
265 | pid = vfork (); |
266 | #else | |
da6d8c04 | 267 | pid = fork (); |
52fb6437 | 268 | #endif |
da6d8c04 DJ |
269 | if (pid < 0) |
270 | perror_with_name ("fork"); | |
271 | ||
272 | if (pid == 0) | |
273 | { | |
274 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
275 | ||
254787d4 | 276 | signal (__SIGRTMIN + 1, SIG_DFL); |
0d62e5e8 | 277 | |
a9fa9f7d DJ |
278 | setpgid (0, 0); |
279 | ||
2b876972 DJ |
280 | execv (program, allargs); |
281 | if (errno == ENOENT) | |
282 | execvp (program, allargs); | |
da6d8c04 DJ |
283 | |
284 | fprintf (stderr, "Cannot exec %s: %s.\n", program, | |
d07c63e7 | 285 | strerror (errno)); |
da6d8c04 DJ |
286 | fflush (stderr); |
287 | _exit (0177); | |
288 | } | |
289 | ||
0d62e5e8 | 290 | new_process = add_process (pid); |
a06660f7 | 291 | add_thread (pid, new_process, pid); |
24a09b5f | 292 | must_set_ptrace_flags = 1; |
611cb4a5 | 293 | |
a9fa9f7d | 294 | return pid; |
da6d8c04 DJ |
295 | } |
296 | ||
297 | /* Attach to an inferior process. */ | |
298 | ||
0d62e5e8 | 299 | void |
24a09b5f | 300 | linux_attach_lwp (unsigned long pid) |
da6d8c04 | 301 | { |
0d62e5e8 | 302 | struct process_info *new_process; |
611cb4a5 | 303 | |
da6d8c04 DJ |
304 | if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0) |
305 | { | |
a1928bad | 306 | fprintf (stderr, "Cannot attach to process %ld: %s (%d)\n", pid, |
43d5792c | 307 | strerror (errno), errno); |
da6d8c04 | 308 | fflush (stderr); |
0d62e5e8 DJ |
309 | |
310 | /* If we fail to attach to an LWP, just return. */ | |
24a09b5f | 311 | if (all_threads.head == NULL) |
0d62e5e8 DJ |
312 | _exit (0177); |
313 | return; | |
da6d8c04 DJ |
314 | } |
315 | ||
24a09b5f DJ |
316 | ptrace (PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACECLONE); |
317 | ||
0d62e5e8 | 318 | new_process = (struct process_info *) add_process (pid); |
24a09b5f DJ |
319 | add_thread (pid, new_process, pid); |
320 | new_thread_notify (thread_id_to_gdb_id (new_process->lwpid)); | |
0d62e5e8 DJ |
321 | |
322 | /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH | |
323 | brings it to a halt. We should ignore that SIGSTOP and resume the process | |
324 | (unless this is the first process, in which case the flag will be cleared | |
325 | in linux_attach). | |
326 | ||
327 | On the other hand, if we are currently trying to stop all threads, we | |
328 | should treat the new thread as if we had sent it a SIGSTOP. This works | |
329 | because we are guaranteed that add_process added us to the end of the | |
330 | list, and so the new thread has not yet reached wait_for_sigstop (but | |
331 | will). */ | |
332 | if (! stopping_threads) | |
333 | new_process->stop_expected = 1; | |
334 | } | |
335 | ||
336 | int | |
a1928bad | 337 | linux_attach (unsigned long pid) |
0d62e5e8 DJ |
338 | { |
339 | struct process_info *process; | |
340 | ||
24a09b5f | 341 | linux_attach_lwp (pid); |
0d62e5e8 | 342 | |
ae13219e DJ |
343 | /* Don't ignore the initial SIGSTOP if we just attached to this process. |
344 | It will be collected by wait shortly. */ | |
0d62e5e8 DJ |
345 | process = (struct process_info *) find_inferior_id (&all_processes, pid); |
346 | process->stop_expected = 0; | |
347 | ||
da6d8c04 DJ |
348 | return 0; |
349 | } | |
350 | ||
351 | /* Kill the inferior process. Make us have no inferior. */ | |
352 | ||
ce3a066d | 353 | static void |
0d62e5e8 | 354 | linux_kill_one_process (struct inferior_list_entry *entry) |
da6d8c04 | 355 | { |
0d62e5e8 DJ |
356 | struct thread_info *thread = (struct thread_info *) entry; |
357 | struct process_info *process = get_thread_process (thread); | |
358 | int wstat; | |
359 | ||
fd500816 DJ |
360 | /* We avoid killing the first thread here, because of a Linux kernel (at |
361 | least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before | |
362 | the children get a chance to be reaped, it will remain a zombie | |
363 | forever. */ | |
364 | if (entry == all_threads.head) | |
365 | return; | |
366 | ||
0d62e5e8 DJ |
367 | do |
368 | { | |
369 | ptrace (PTRACE_KILL, pid_of (process), 0, 0); | |
370 | ||
371 | /* Make sure it died. The loop is most likely unnecessary. */ | |
372 | wstat = linux_wait_for_event (thread); | |
373 | } while (WIFSTOPPED (wstat)); | |
da6d8c04 DJ |
374 | } |
375 | ||
0d62e5e8 DJ |
376 | static void |
377 | linux_kill (void) | |
378 | { | |
fd500816 | 379 | struct thread_info *thread = (struct thread_info *) all_threads.head; |
9d606399 | 380 | struct process_info *process; |
fd500816 DJ |
381 | int wstat; |
382 | ||
9d606399 DJ |
383 | if (thread == NULL) |
384 | return; | |
385 | ||
0d62e5e8 | 386 | for_each_inferior (&all_threads, linux_kill_one_process); |
fd500816 DJ |
387 | |
388 | /* See the comment in linux_kill_one_process. We did not kill the first | |
389 | thread in the list, so do so now. */ | |
9d606399 | 390 | process = get_thread_process (thread); |
fd500816 DJ |
391 | do |
392 | { | |
393 | ptrace (PTRACE_KILL, pid_of (process), 0, 0); | |
394 | ||
395 | /* Make sure it died. The loop is most likely unnecessary. */ | |
396 | wstat = linux_wait_for_event (thread); | |
397 | } while (WIFSTOPPED (wstat)); | |
0d62e5e8 DJ |
398 | } |
399 | ||
6ad8ae5c DJ |
400 | static void |
401 | linux_detach_one_process (struct inferior_list_entry *entry) | |
402 | { | |
403 | struct thread_info *thread = (struct thread_info *) entry; | |
404 | struct process_info *process = get_thread_process (thread); | |
405 | ||
ae13219e DJ |
406 | /* Make sure the process isn't stopped at a breakpoint that's |
407 | no longer there. */ | |
408 | check_removed_breakpoint (process); | |
409 | ||
410 | /* If this process is stopped but is expecting a SIGSTOP, then make | |
411 | sure we take care of that now. This isn't absolutely guaranteed | |
412 | to collect the SIGSTOP, but is fairly likely to. */ | |
413 | if (process->stop_expected) | |
414 | { | |
415 | /* Clear stop_expected, so that the SIGSTOP will be reported. */ | |
416 | process->stop_expected = 0; | |
417 | if (process->stopped) | |
418 | linux_resume_one_process (&process->head, 0, 0, NULL); | |
419 | linux_wait_for_event (thread); | |
420 | } | |
421 | ||
422 | /* Flush any pending changes to the process's registers. */ | |
423 | regcache_invalidate_one ((struct inferior_list_entry *) | |
424 | get_process_thread (process)); | |
425 | ||
426 | /* Finally, let it resume. */ | |
6ad8ae5c DJ |
427 | ptrace (PTRACE_DETACH, pid_of (process), 0, 0); |
428 | } | |
429 | ||
dd6953e1 | 430 | static int |
6ad8ae5c DJ |
431 | linux_detach (void) |
432 | { | |
ae13219e | 433 | delete_all_breakpoints (); |
6ad8ae5c | 434 | for_each_inferior (&all_threads, linux_detach_one_process); |
ae13219e | 435 | clear_inferiors (); |
dd6953e1 | 436 | return 0; |
6ad8ae5c DJ |
437 | } |
438 | ||
444d6139 PA |
439 | static void |
440 | linux_join (void) | |
441 | { | |
442 | extern unsigned long signal_pid; | |
443 | int status, ret; | |
444 | ||
445 | do { | |
446 | ret = waitpid (signal_pid, &status, 0); | |
447 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
448 | break; | |
449 | } while (ret != -1 || errno != ECHILD); | |
450 | } | |
451 | ||
6ad8ae5c | 452 | /* Return nonzero if the given thread is still alive. */ |
0d62e5e8 | 453 | static int |
24a09b5f | 454 | linux_thread_alive (unsigned long lwpid) |
0d62e5e8 | 455 | { |
24a09b5f | 456 | if (find_inferior_id (&all_threads, lwpid) != NULL) |
0d62e5e8 DJ |
457 | return 1; |
458 | else | |
459 | return 0; | |
460 | } | |
461 | ||
462 | /* Return nonzero if this process stopped at a breakpoint which | |
463 | no longer appears to be inserted. Also adjust the PC | |
464 | appropriately to resume where the breakpoint used to be. */ | |
ce3a066d | 465 | static int |
0d62e5e8 | 466 | check_removed_breakpoint (struct process_info *event_child) |
da6d8c04 | 467 | { |
0d62e5e8 DJ |
468 | CORE_ADDR stop_pc; |
469 | struct thread_info *saved_inferior; | |
470 | ||
471 | if (event_child->pending_is_breakpoint == 0) | |
472 | return 0; | |
473 | ||
474 | if (debug_threads) | |
ae13219e DJ |
475 | fprintf (stderr, "Checking for breakpoint in process %ld.\n", |
476 | event_child->lwpid); | |
0d62e5e8 DJ |
477 | |
478 | saved_inferior = current_inferior; | |
479 | current_inferior = get_process_thread (event_child); | |
480 | ||
481 | stop_pc = get_stop_pc (); | |
482 | ||
483 | /* If the PC has changed since we stopped, then we shouldn't do | |
484 | anything. This happens if, for instance, GDB handled the | |
485 | decr_pc_after_break subtraction itself. */ | |
486 | if (stop_pc != event_child->pending_stop_pc) | |
487 | { | |
488 | if (debug_threads) | |
ae13219e DJ |
489 | fprintf (stderr, "Ignoring, PC was changed. Old PC was 0x%08llx\n", |
490 | event_child->pending_stop_pc); | |
0d62e5e8 DJ |
491 | |
492 | event_child->pending_is_breakpoint = 0; | |
493 | current_inferior = saved_inferior; | |
494 | return 0; | |
495 | } | |
496 | ||
497 | /* If the breakpoint is still there, we will report hitting it. */ | |
498 | if ((*the_low_target.breakpoint_at) (stop_pc)) | |
499 | { | |
500 | if (debug_threads) | |
501 | fprintf (stderr, "Ignoring, breakpoint is still present.\n"); | |
502 | current_inferior = saved_inferior; | |
503 | return 0; | |
504 | } | |
505 | ||
506 | if (debug_threads) | |
507 | fprintf (stderr, "Removed breakpoint.\n"); | |
508 | ||
509 | /* For decr_pc_after_break targets, here is where we perform the | |
510 | decrement. We go immediately from this function to resuming, | |
511 | and can not safely call get_stop_pc () again. */ | |
512 | if (the_low_target.set_pc != NULL) | |
513 | (*the_low_target.set_pc) (stop_pc); | |
514 | ||
515 | /* We consumed the pending SIGTRAP. */ | |
5544ad89 | 516 | event_child->pending_is_breakpoint = 0; |
0d62e5e8 DJ |
517 | event_child->status_pending_p = 0; |
518 | event_child->status_pending = 0; | |
519 | ||
520 | current_inferior = saved_inferior; | |
da6d8c04 DJ |
521 | return 1; |
522 | } | |
523 | ||
0d62e5e8 DJ |
524 | /* Return 1 if this process has an interesting status pending. This function |
525 | may silently resume an inferior process. */ | |
611cb4a5 | 526 | static int |
0d62e5e8 DJ |
527 | status_pending_p (struct inferior_list_entry *entry, void *dummy) |
528 | { | |
529 | struct process_info *process = (struct process_info *) entry; | |
530 | ||
531 | if (process->status_pending_p) | |
532 | if (check_removed_breakpoint (process)) | |
533 | { | |
534 | /* This thread was stopped at a breakpoint, and the breakpoint | |
535 | is now gone. We were told to continue (or step...) all threads, | |
536 | so GDB isn't trying to single-step past this breakpoint. | |
537 | So instead of reporting the old SIGTRAP, pretend we got to | |
538 | the breakpoint just after it was removed instead of just | |
539 | before; resume the process. */ | |
32ca6d61 | 540 | linux_resume_one_process (&process->head, 0, 0, NULL); |
0d62e5e8 DJ |
541 | return 0; |
542 | } | |
543 | ||
544 | return process->status_pending_p; | |
545 | } | |
546 | ||
547 | static void | |
548 | linux_wait_for_process (struct process_info **childp, int *wstatp) | |
611cb4a5 | 549 | { |
0d62e5e8 DJ |
550 | int ret; |
551 | int to_wait_for = -1; | |
552 | ||
553 | if (*childp != NULL) | |
554 | to_wait_for = (*childp)->lwpid; | |
611cb4a5 | 555 | |
24a09b5f | 556 | retry: |
611cb4a5 DJ |
557 | while (1) |
558 | { | |
0d62e5e8 DJ |
559 | ret = waitpid (to_wait_for, wstatp, WNOHANG); |
560 | ||
561 | if (ret == -1) | |
562 | { | |
563 | if (errno != ECHILD) | |
564 | perror_with_name ("waitpid"); | |
565 | } | |
566 | else if (ret > 0) | |
567 | break; | |
568 | ||
569 | ret = waitpid (to_wait_for, wstatp, WNOHANG | __WCLONE); | |
570 | ||
571 | if (ret == -1) | |
572 | { | |
573 | if (errno != ECHILD) | |
574 | perror_with_name ("waitpid (WCLONE)"); | |
575 | } | |
576 | else if (ret > 0) | |
577 | break; | |
578 | ||
579 | usleep (1000); | |
580 | } | |
581 | ||
582 | if (debug_threads | |
583 | && (!WIFSTOPPED (*wstatp) | |
584 | || (WSTOPSIG (*wstatp) != 32 | |
585 | && WSTOPSIG (*wstatp) != 33))) | |
586 | fprintf (stderr, "Got an event from %d (%x)\n", ret, *wstatp); | |
587 | ||
588 | if (to_wait_for == -1) | |
589 | *childp = (struct process_info *) find_inferior_id (&all_processes, ret); | |
590 | ||
24a09b5f DJ |
591 | /* If we didn't find a process, one of two things presumably happened: |
592 | - A process we started and then detached from has exited. Ignore it. | |
593 | - A process we are controlling has forked and the new child's stop | |
594 | was reported to us by the kernel. Save its PID. */ | |
595 | if (*childp == NULL && WIFSTOPPED (*wstatp)) | |
596 | { | |
597 | add_pid_to_list (&stopped_pids, ret); | |
598 | goto retry; | |
599 | } | |
600 | else if (*childp == NULL) | |
601 | goto retry; | |
602 | ||
0d62e5e8 DJ |
603 | (*childp)->stopped = 1; |
604 | (*childp)->pending_is_breakpoint = 0; | |
605 | ||
32ca6d61 DJ |
606 | (*childp)->last_status = *wstatp; |
607 | ||
0d62e5e8 DJ |
608 | if (debug_threads |
609 | && WIFSTOPPED (*wstatp)) | |
610 | { | |
611 | current_inferior = (struct thread_info *) | |
24a09b5f | 612 | find_inferior_id (&all_threads, (*childp)->lwpid); |
0d62e5e8 DJ |
613 | /* For testing only; i386_stop_pc prints out a diagnostic. */ |
614 | if (the_low_target.get_pc != NULL) | |
615 | get_stop_pc (); | |
616 | } | |
617 | } | |
611cb4a5 | 618 | |
0d62e5e8 DJ |
619 | static int |
620 | linux_wait_for_event (struct thread_info *child) | |
621 | { | |
622 | CORE_ADDR stop_pc; | |
623 | struct process_info *event_child; | |
624 | int wstat; | |
625 | ||
626 | /* Check for a process with a pending status. */ | |
627 | /* It is possible that the user changed the pending task's registers since | |
628 | it stopped. We correctly handle the change of PC if we hit a breakpoint | |
e5379b03 | 629 | (in check_removed_breakpoint); signals should be reported anyway. */ |
0d62e5e8 DJ |
630 | if (child == NULL) |
631 | { | |
632 | event_child = (struct process_info *) | |
633 | find_inferior (&all_processes, status_pending_p, NULL); | |
634 | if (debug_threads && event_child) | |
a1928bad | 635 | fprintf (stderr, "Got a pending child %ld\n", event_child->lwpid); |
0d62e5e8 DJ |
636 | } |
637 | else | |
638 | { | |
639 | event_child = get_thread_process (child); | |
640 | if (event_child->status_pending_p | |
641 | && check_removed_breakpoint (event_child)) | |
642 | event_child = NULL; | |
643 | } | |
611cb4a5 | 644 | |
0d62e5e8 DJ |
645 | if (event_child != NULL) |
646 | { | |
647 | if (event_child->status_pending_p) | |
611cb4a5 | 648 | { |
0d62e5e8 | 649 | if (debug_threads) |
a1928bad | 650 | fprintf (stderr, "Got an event from pending child %ld (%04x)\n", |
0d62e5e8 DJ |
651 | event_child->lwpid, event_child->status_pending); |
652 | wstat = event_child->status_pending; | |
653 | event_child->status_pending_p = 0; | |
654 | event_child->status_pending = 0; | |
655 | current_inferior = get_process_thread (event_child); | |
656 | return wstat; | |
657 | } | |
658 | } | |
659 | ||
660 | /* We only enter this loop if no process has a pending wait status. Thus | |
661 | any action taken in response to a wait status inside this loop is | |
662 | responding as soon as we detect the status, not after any pending | |
663 | events. */ | |
664 | while (1) | |
665 | { | |
666 | if (child == NULL) | |
667 | event_child = NULL; | |
668 | else | |
669 | event_child = get_thread_process (child); | |
670 | ||
671 | linux_wait_for_process (&event_child, &wstat); | |
672 | ||
673 | if (event_child == NULL) | |
674 | error ("event from unknown child"); | |
611cb4a5 | 675 | |
0d62e5e8 | 676 | current_inferior = (struct thread_info *) |
24a09b5f | 677 | find_inferior_id (&all_threads, event_child->lwpid); |
0d62e5e8 | 678 | |
89be2091 | 679 | /* Check for thread exit. */ |
24a09b5f | 680 | if (! WIFSTOPPED (wstat)) |
0d62e5e8 | 681 | { |
89be2091 | 682 | if (debug_threads) |
24a09b5f | 683 | fprintf (stderr, "LWP %ld exiting\n", event_child->head.id); |
89be2091 DJ |
684 | |
685 | /* If the last thread is exiting, just return. */ | |
686 | if (all_threads.head == all_threads.tail) | |
687 | return wstat; | |
688 | ||
24a09b5f | 689 | dead_thread_notify (thread_id_to_gdb_id (event_child->lwpid)); |
89be2091 DJ |
690 | |
691 | remove_inferior (&all_processes, &event_child->head); | |
692 | free (event_child); | |
693 | remove_thread (current_inferior); | |
694 | current_inferior = (struct thread_info *) all_threads.head; | |
695 | ||
696 | /* If we were waiting for this particular child to do something... | |
697 | well, it did something. */ | |
698 | if (child != NULL) | |
699 | return wstat; | |
700 | ||
701 | /* Wait for a more interesting event. */ | |
702 | continue; | |
703 | } | |
704 | ||
24a09b5f | 705 | if (WIFSTOPPED (wstat) |
89be2091 DJ |
706 | && WSTOPSIG (wstat) == SIGSTOP |
707 | && event_child->stop_expected) | |
708 | { | |
709 | if (debug_threads) | |
710 | fprintf (stderr, "Expected stop.\n"); | |
711 | event_child->stop_expected = 0; | |
712 | linux_resume_one_process (&event_child->head, | |
713 | event_child->stepping, 0, NULL); | |
714 | continue; | |
715 | } | |
716 | ||
24a09b5f DJ |
717 | if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP |
718 | && wstat >> 16 != 0) | |
719 | { | |
720 | handle_extended_wait (event_child, wstat); | |
721 | continue; | |
722 | } | |
723 | ||
89be2091 DJ |
724 | /* If GDB is not interested in this signal, don't stop other |
725 | threads, and don't report it to GDB. Just resume the | |
726 | inferior right away. We do this for threading-related | |
69f223ed DJ |
727 | signals as well as any that GDB specifically requested we |
728 | ignore. But never ignore SIGSTOP if we sent it ourselves, | |
729 | and do not ignore signals when stepping - they may require | |
730 | special handling to skip the signal handler. */ | |
89be2091 DJ |
731 | /* FIXME drow/2002-06-09: Get signal numbers from the inferior's |
732 | thread library? */ | |
733 | if (WIFSTOPPED (wstat) | |
69f223ed | 734 | && !event_child->stepping |
24a09b5f DJ |
735 | && ( |
736 | #ifdef USE_THREAD_DB | |
737 | (thread_db_active && (WSTOPSIG (wstat) == __SIGRTMIN | |
738 | || WSTOPSIG (wstat) == __SIGRTMIN + 1)) | |
739 | || | |
740 | #endif | |
741 | (pass_signals[target_signal_from_host (WSTOPSIG (wstat))] | |
742 | && (WSTOPSIG (wstat) != SIGSTOP || !stopping_threads)))) | |
89be2091 DJ |
743 | { |
744 | siginfo_t info, *info_p; | |
745 | ||
746 | if (debug_threads) | |
24a09b5f DJ |
747 | fprintf (stderr, "Ignored signal %d for LWP %ld.\n", |
748 | WSTOPSIG (wstat), event_child->head.id); | |
89be2091 DJ |
749 | |
750 | if (ptrace (PTRACE_GETSIGINFO, event_child->lwpid, 0, &info) == 0) | |
751 | info_p = &info; | |
752 | else | |
753 | info_p = NULL; | |
754 | linux_resume_one_process (&event_child->head, | |
755 | event_child->stepping, | |
756 | WSTOPSIG (wstat), info_p); | |
757 | continue; | |
0d62e5e8 | 758 | } |
611cb4a5 | 759 | |
0d62e5e8 DJ |
760 | /* If this event was not handled above, and is not a SIGTRAP, report |
761 | it. */ | |
762 | if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGTRAP) | |
763 | return wstat; | |
611cb4a5 | 764 | |
0d62e5e8 DJ |
765 | /* If this target does not support breakpoints, we simply report the |
766 | SIGTRAP; it's of no concern to us. */ | |
767 | if (the_low_target.get_pc == NULL) | |
768 | return wstat; | |
769 | ||
770 | stop_pc = get_stop_pc (); | |
771 | ||
772 | /* bp_reinsert will only be set if we were single-stepping. | |
773 | Notice that we will resume the process after hitting | |
774 | a gdbserver breakpoint; single-stepping to/over one | |
775 | is not supported (yet). */ | |
776 | if (event_child->bp_reinsert != 0) | |
777 | { | |
778 | if (debug_threads) | |
779 | fprintf (stderr, "Reinserted breakpoint.\n"); | |
780 | reinsert_breakpoint (event_child->bp_reinsert); | |
781 | event_child->bp_reinsert = 0; | |
782 | ||
783 | /* Clear the single-stepping flag and SIGTRAP as we resume. */ | |
32ca6d61 | 784 | linux_resume_one_process (&event_child->head, 0, 0, NULL); |
0d62e5e8 DJ |
785 | continue; |
786 | } | |
787 | ||
788 | if (debug_threads) | |
789 | fprintf (stderr, "Hit a (non-reinsert) breakpoint.\n"); | |
790 | ||
791 | if (check_breakpoints (stop_pc) != 0) | |
792 | { | |
793 | /* We hit one of our own breakpoints. We mark it as a pending | |
e5379b03 | 794 | breakpoint, so that check_removed_breakpoint () will do the PC |
0d62e5e8 DJ |
795 | adjustment for us at the appropriate time. */ |
796 | event_child->pending_is_breakpoint = 1; | |
797 | event_child->pending_stop_pc = stop_pc; | |
798 | ||
799 | /* Now we need to put the breakpoint back. We continue in the event | |
800 | loop instead of simply replacing the breakpoint right away, | |
801 | in order to not lose signals sent to the thread that hit the | |
802 | breakpoint. Unfortunately this increases the window where another | |
803 | thread could sneak past the removed breakpoint. For the current | |
804 | use of server-side breakpoints (thread creation) this is | |
805 | acceptable; but it needs to be considered before this breakpoint | |
806 | mechanism can be used in more general ways. For some breakpoints | |
807 | it may be necessary to stop all other threads, but that should | |
808 | be avoided where possible. | |
809 | ||
810 | If breakpoint_reinsert_addr is NULL, that means that we can | |
811 | use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint, | |
812 | mark it for reinsertion, and single-step. | |
813 | ||
814 | Otherwise, call the target function to figure out where we need | |
815 | our temporary breakpoint, create it, and continue executing this | |
816 | process. */ | |
817 | if (the_low_target.breakpoint_reinsert_addr == NULL) | |
818 | { | |
819 | event_child->bp_reinsert = stop_pc; | |
820 | uninsert_breakpoint (stop_pc); | |
32ca6d61 | 821 | linux_resume_one_process (&event_child->head, 1, 0, NULL); |
0d62e5e8 DJ |
822 | } |
823 | else | |
824 | { | |
825 | reinsert_breakpoint_by_bp | |
826 | (stop_pc, (*the_low_target.breakpoint_reinsert_addr) ()); | |
32ca6d61 | 827 | linux_resume_one_process (&event_child->head, 0, 0, NULL); |
611cb4a5 | 828 | } |
0d62e5e8 DJ |
829 | |
830 | continue; | |
831 | } | |
832 | ||
833 | /* If we were single-stepping, we definitely want to report the | |
834 | SIGTRAP. The single-step operation has completed, so also | |
aa691b87 | 835 | clear the stepping flag; in general this does not matter, |
0d62e5e8 DJ |
836 | because the SIGTRAP will be reported to the client, which |
837 | will give us a new action for this thread, but clear it for | |
838 | consistency anyway. It's safe to clear the stepping flag | |
839 | because the only consumer of get_stop_pc () after this point | |
e5379b03 | 840 | is check_removed_breakpoint, and pending_is_breakpoint is not |
0d62e5e8 DJ |
841 | set. It might be wiser to use a step_completed flag instead. */ |
842 | if (event_child->stepping) | |
843 | { | |
844 | event_child->stepping = 0; | |
845 | return wstat; | |
846 | } | |
847 | ||
848 | /* A SIGTRAP that we can't explain. It may have been a breakpoint. | |
849 | Check if it is a breakpoint, and if so mark the process information | |
850 | accordingly. This will handle both the necessary fiddling with the | |
851 | PC on decr_pc_after_break targets and suppressing extra threads | |
852 | hitting a breakpoint if two hit it at once and then GDB removes it | |
853 | after the first is reported. Arguably it would be better to report | |
854 | multiple threads hitting breakpoints simultaneously, but the current | |
855 | remote protocol does not allow this. */ | |
856 | if ((*the_low_target.breakpoint_at) (stop_pc)) | |
857 | { | |
858 | event_child->pending_is_breakpoint = 1; | |
859 | event_child->pending_stop_pc = stop_pc; | |
611cb4a5 DJ |
860 | } |
861 | ||
862 | return wstat; | |
863 | } | |
0d62e5e8 | 864 | |
611cb4a5 DJ |
865 | /* NOTREACHED */ |
866 | return 0; | |
867 | } | |
868 | ||
0d62e5e8 | 869 | /* Wait for process, returns status. */ |
da6d8c04 | 870 | |
ce3a066d DJ |
871 | static unsigned char |
872 | linux_wait (char *status) | |
da6d8c04 | 873 | { |
e5f1222d | 874 | int w; |
0d62e5e8 DJ |
875 | struct thread_info *child = NULL; |
876 | ||
877 | retry: | |
878 | /* If we were only supposed to resume one thread, only wait for | |
879 | that thread - if it's still alive. If it died, however - which | |
880 | can happen if we're coming from the thread death case below - | |
881 | then we need to make sure we restart the other threads. We could | |
882 | pick a thread at random or restart all; restarting all is less | |
883 | arbitrary. */ | |
d592fa2f | 884 | if (cont_thread != 0 && cont_thread != -1) |
0d62e5e8 DJ |
885 | { |
886 | child = (struct thread_info *) find_inferior_id (&all_threads, | |
887 | cont_thread); | |
888 | ||
889 | /* No stepping, no signal - unless one is pending already, of course. */ | |
890 | if (child == NULL) | |
64386c31 DJ |
891 | { |
892 | struct thread_resume resume_info; | |
893 | resume_info.thread = -1; | |
894 | resume_info.step = resume_info.sig = resume_info.leave_stopped = 0; | |
895 | linux_resume (&resume_info); | |
896 | } | |
0d62e5e8 | 897 | } |
da6d8c04 DJ |
898 | |
899 | enable_async_io (); | |
62ea82f5 | 900 | unblock_async_io (); |
0d62e5e8 DJ |
901 | w = linux_wait_for_event (child); |
902 | stop_all_processes (); | |
da6d8c04 | 903 | disable_async_io (); |
da6d8c04 | 904 | |
24a09b5f DJ |
905 | if (must_set_ptrace_flags) |
906 | { | |
907 | ptrace (PTRACE_SETOPTIONS, inferior_pid, 0, PTRACE_O_TRACECLONE); | |
908 | must_set_ptrace_flags = 0; | |
909 | } | |
910 | ||
0d62e5e8 DJ |
911 | /* If we are waiting for a particular child, and it exited, |
912 | linux_wait_for_event will return its exit status. Similarly if | |
913 | the last child exited. If this is not the last child, however, | |
914 | do not report it as exited until there is a 'thread exited' response | |
915 | available in the remote protocol. Instead, just wait for another event. | |
916 | This should be safe, because if the thread crashed we will already | |
917 | have reported the termination signal to GDB; that should stop any | |
918 | in-progress stepping operations, etc. | |
919 | ||
920 | Report the exit status of the last thread to exit. This matches | |
921 | LinuxThreads' behavior. */ | |
922 | ||
923 | if (all_threads.head == all_threads.tail) | |
da6d8c04 | 924 | { |
0d62e5e8 DJ |
925 | if (WIFEXITED (w)) |
926 | { | |
927 | fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w)); | |
928 | *status = 'W'; | |
929 | clear_inferiors (); | |
075b3282 DJ |
930 | free (all_processes.head); |
931 | all_processes.head = all_processes.tail = NULL; | |
b80864fb | 932 | return WEXITSTATUS (w); |
0d62e5e8 DJ |
933 | } |
934 | else if (!WIFSTOPPED (w)) | |
935 | { | |
936 | fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w)); | |
0d62e5e8 | 937 | *status = 'X'; |
075b3282 DJ |
938 | clear_inferiors (); |
939 | free (all_processes.head); | |
940 | all_processes.head = all_processes.tail = NULL; | |
b80864fb | 941 | return target_signal_from_host (WTERMSIG (w)); |
0d62e5e8 | 942 | } |
da6d8c04 | 943 | } |
0d62e5e8 | 944 | else |
da6d8c04 | 945 | { |
0d62e5e8 DJ |
946 | if (!WIFSTOPPED (w)) |
947 | goto retry; | |
da6d8c04 DJ |
948 | } |
949 | ||
da6d8c04 | 950 | *status = 'T'; |
b80864fb | 951 | return target_signal_from_host (WSTOPSIG (w)); |
da6d8c04 DJ |
952 | } |
953 | ||
fd500816 DJ |
954 | /* Send a signal to an LWP. For LinuxThreads, kill is enough; however, if |
955 | thread groups are in use, we need to use tkill. */ | |
956 | ||
957 | static int | |
a1928bad | 958 | kill_lwp (unsigned long lwpid, int signo) |
fd500816 DJ |
959 | { |
960 | static int tkill_failed; | |
961 | ||
962 | errno = 0; | |
963 | ||
964 | #ifdef SYS_tkill | |
965 | if (!tkill_failed) | |
966 | { | |
967 | int ret = syscall (SYS_tkill, lwpid, signo); | |
968 | if (errno != ENOSYS) | |
969 | return ret; | |
970 | errno = 0; | |
971 | tkill_failed = 1; | |
972 | } | |
973 | #endif | |
974 | ||
975 | return kill (lwpid, signo); | |
976 | } | |
977 | ||
0d62e5e8 DJ |
978 | static void |
979 | send_sigstop (struct inferior_list_entry *entry) | |
980 | { | |
981 | struct process_info *process = (struct process_info *) entry; | |
982 | ||
983 | if (process->stopped) | |
984 | return; | |
985 | ||
986 | /* If we already have a pending stop signal for this process, don't | |
987 | send another. */ | |
988 | if (process->stop_expected) | |
989 | { | |
ae13219e DJ |
990 | if (debug_threads) |
991 | fprintf (stderr, "Have pending sigstop for process %ld\n", | |
992 | process->lwpid); | |
993 | ||
994 | /* We clear the stop_expected flag so that wait_for_sigstop | |
995 | will receive the SIGSTOP event (instead of silently resuming and | |
996 | waiting again). It'll be reset below. */ | |
0d62e5e8 DJ |
997 | process->stop_expected = 0; |
998 | return; | |
999 | } | |
1000 | ||
1001 | if (debug_threads) | |
a1928bad | 1002 | fprintf (stderr, "Sending sigstop to process %ld\n", process->head.id); |
0d62e5e8 | 1003 | |
fd500816 | 1004 | kill_lwp (process->head.id, SIGSTOP); |
0d62e5e8 DJ |
1005 | } |
1006 | ||
1007 | static void | |
1008 | wait_for_sigstop (struct inferior_list_entry *entry) | |
1009 | { | |
1010 | struct process_info *process = (struct process_info *) entry; | |
1011 | struct thread_info *saved_inferior, *thread; | |
a1928bad DJ |
1012 | int wstat; |
1013 | unsigned long saved_tid; | |
0d62e5e8 DJ |
1014 | |
1015 | if (process->stopped) | |
1016 | return; | |
1017 | ||
1018 | saved_inferior = current_inferior; | |
1019 | saved_tid = ((struct inferior_list_entry *) saved_inferior)->id; | |
1020 | thread = (struct thread_info *) find_inferior_id (&all_threads, | |
24a09b5f | 1021 | process->lwpid); |
0d62e5e8 DJ |
1022 | wstat = linux_wait_for_event (thread); |
1023 | ||
1024 | /* If we stopped with a non-SIGSTOP signal, save it for later | |
1025 | and record the pending SIGSTOP. If the process exited, just | |
1026 | return. */ | |
1027 | if (WIFSTOPPED (wstat) | |
1028 | && WSTOPSIG (wstat) != SIGSTOP) | |
1029 | { | |
1030 | if (debug_threads) | |
24a09b5f DJ |
1031 | fprintf (stderr, "LWP %ld stopped with non-sigstop status %06x\n", |
1032 | process->lwpid, wstat); | |
0d62e5e8 DJ |
1033 | process->status_pending_p = 1; |
1034 | process->status_pending = wstat; | |
1035 | process->stop_expected = 1; | |
1036 | } | |
1037 | ||
1038 | if (linux_thread_alive (saved_tid)) | |
1039 | current_inferior = saved_inferior; | |
1040 | else | |
1041 | { | |
1042 | if (debug_threads) | |
1043 | fprintf (stderr, "Previously current thread died.\n"); | |
1044 | ||
1045 | /* Set a valid thread as current. */ | |
1046 | set_desired_inferior (0); | |
1047 | } | |
1048 | } | |
1049 | ||
1050 | static void | |
1051 | stop_all_processes (void) | |
1052 | { | |
1053 | stopping_threads = 1; | |
1054 | for_each_inferior (&all_processes, send_sigstop); | |
1055 | for_each_inferior (&all_processes, wait_for_sigstop); | |
1056 | stopping_threads = 0; | |
1057 | } | |
1058 | ||
da6d8c04 DJ |
1059 | /* Resume execution of the inferior process. |
1060 | If STEP is nonzero, single-step it. | |
1061 | If SIGNAL is nonzero, give it that signal. */ | |
1062 | ||
ce3a066d | 1063 | static void |
0d62e5e8 | 1064 | linux_resume_one_process (struct inferior_list_entry *entry, |
32ca6d61 | 1065 | int step, int signal, siginfo_t *info) |
da6d8c04 | 1066 | { |
0d62e5e8 DJ |
1067 | struct process_info *process = (struct process_info *) entry; |
1068 | struct thread_info *saved_inferior; | |
1069 | ||
1070 | if (process->stopped == 0) | |
1071 | return; | |
1072 | ||
1073 | /* If we have pending signals or status, and a new signal, enqueue the | |
1074 | signal. Also enqueue the signal if we are waiting to reinsert a | |
1075 | breakpoint; it will be picked up again below. */ | |
1076 | if (signal != 0 | |
1077 | && (process->status_pending_p || process->pending_signals != NULL | |
1078 | || process->bp_reinsert != 0)) | |
1079 | { | |
1080 | struct pending_signals *p_sig; | |
1081 | p_sig = malloc (sizeof (*p_sig)); | |
1082 | p_sig->prev = process->pending_signals; | |
1083 | p_sig->signal = signal; | |
32ca6d61 DJ |
1084 | if (info == NULL) |
1085 | memset (&p_sig->info, 0, sizeof (siginfo_t)); | |
1086 | else | |
1087 | memcpy (&p_sig->info, info, sizeof (siginfo_t)); | |
0d62e5e8 DJ |
1088 | process->pending_signals = p_sig; |
1089 | } | |
1090 | ||
e5379b03 | 1091 | if (process->status_pending_p && !check_removed_breakpoint (process)) |
0d62e5e8 DJ |
1092 | return; |
1093 | ||
1094 | saved_inferior = current_inferior; | |
1095 | current_inferior = get_process_thread (process); | |
1096 | ||
1097 | if (debug_threads) | |
a1928bad | 1098 | fprintf (stderr, "Resuming process %ld (%s, signal %d, stop %s)\n", inferior_pid, |
0d62e5e8 DJ |
1099 | step ? "step" : "continue", signal, |
1100 | process->stop_expected ? "expected" : "not expected"); | |
1101 | ||
1102 | /* This bit needs some thinking about. If we get a signal that | |
1103 | we must report while a single-step reinsert is still pending, | |
1104 | we often end up resuming the thread. It might be better to | |
1105 | (ew) allow a stack of pending events; then we could be sure that | |
1106 | the reinsert happened right away and not lose any signals. | |
1107 | ||
1108 | Making this stack would also shrink the window in which breakpoints are | |
1109 | uninserted (see comment in linux_wait_for_process) but not enough for | |
1110 | complete correctness, so it won't solve that problem. It may be | |
1111 | worthwhile just to solve this one, however. */ | |
1112 | if (process->bp_reinsert != 0) | |
1113 | { | |
1114 | if (debug_threads) | |
1115 | fprintf (stderr, " pending reinsert at %08lx", (long)process->bp_reinsert); | |
1116 | if (step == 0) | |
1117 | fprintf (stderr, "BAD - reinserting but not stepping.\n"); | |
1118 | step = 1; | |
1119 | ||
1120 | /* Postpone any pending signal. It was enqueued above. */ | |
1121 | signal = 0; | |
1122 | } | |
1123 | ||
1124 | check_removed_breakpoint (process); | |
1125 | ||
aa691b87 | 1126 | if (debug_threads && the_low_target.get_pc != NULL) |
0d62e5e8 DJ |
1127 | { |
1128 | fprintf (stderr, " "); | |
52fb6437 | 1129 | (*the_low_target.get_pc) (); |
0d62e5e8 DJ |
1130 | } |
1131 | ||
1132 | /* If we have pending signals, consume one unless we are trying to reinsert | |
1133 | a breakpoint. */ | |
1134 | if (process->pending_signals != NULL && process->bp_reinsert == 0) | |
1135 | { | |
1136 | struct pending_signals **p_sig; | |
1137 | ||
1138 | p_sig = &process->pending_signals; | |
1139 | while ((*p_sig)->prev != NULL) | |
1140 | p_sig = &(*p_sig)->prev; | |
1141 | ||
1142 | signal = (*p_sig)->signal; | |
32ca6d61 DJ |
1143 | if ((*p_sig)->info.si_signo != 0) |
1144 | ptrace (PTRACE_SETSIGINFO, process->lwpid, 0, &(*p_sig)->info); | |
1145 | ||
0d62e5e8 DJ |
1146 | free (*p_sig); |
1147 | *p_sig = NULL; | |
1148 | } | |
1149 | ||
1150 | regcache_invalidate_one ((struct inferior_list_entry *) | |
1151 | get_process_thread (process)); | |
da6d8c04 | 1152 | errno = 0; |
0d62e5e8 DJ |
1153 | process->stopped = 0; |
1154 | process->stepping = step; | |
1155 | ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, process->lwpid, 0, signal); | |
1156 | ||
1157 | current_inferior = saved_inferior; | |
da6d8c04 DJ |
1158 | if (errno) |
1159 | perror_with_name ("ptrace"); | |
1160 | } | |
1161 | ||
64386c31 DJ |
1162 | static struct thread_resume *resume_ptr; |
1163 | ||
1164 | /* This function is called once per thread. We look up the thread | |
5544ad89 DJ |
1165 | in RESUME_PTR, and mark the thread with a pointer to the appropriate |
1166 | resume request. | |
1167 | ||
1168 | This algorithm is O(threads * resume elements), but resume elements | |
1169 | is small (and will remain small at least until GDB supports thread | |
1170 | suspension). */ | |
0d62e5e8 | 1171 | static void |
5544ad89 | 1172 | linux_set_resume_request (struct inferior_list_entry *entry) |
0d62e5e8 DJ |
1173 | { |
1174 | struct process_info *process; | |
64386c31 | 1175 | struct thread_info *thread; |
5544ad89 | 1176 | int ndx; |
64386c31 DJ |
1177 | |
1178 | thread = (struct thread_info *) entry; | |
1179 | process = get_thread_process (thread); | |
1180 | ||
1181 | ndx = 0; | |
1182 | while (resume_ptr[ndx].thread != -1 && resume_ptr[ndx].thread != entry->id) | |
1183 | ndx++; | |
1184 | ||
5544ad89 DJ |
1185 | process->resume = &resume_ptr[ndx]; |
1186 | } | |
1187 | ||
1188 | /* This function is called once per thread. We check the thread's resume | |
1189 | request, which will tell us whether to resume, step, or leave the thread | |
1190 | stopped; and what signal, if any, it should be sent. For threads which | |
1191 | we aren't explicitly told otherwise, we preserve the stepping flag; this | |
1192 | is used for stepping over gdbserver-placed breakpoints. */ | |
1193 | ||
1194 | static void | |
1195 | linux_continue_one_thread (struct inferior_list_entry *entry) | |
1196 | { | |
1197 | struct process_info *process; | |
1198 | struct thread_info *thread; | |
1199 | int step; | |
1200 | ||
1201 | thread = (struct thread_info *) entry; | |
1202 | process = get_thread_process (thread); | |
1203 | ||
1204 | if (process->resume->leave_stopped) | |
64386c31 DJ |
1205 | return; |
1206 | ||
5544ad89 DJ |
1207 | if (process->resume->thread == -1) |
1208 | step = process->stepping || process->resume->step; | |
64386c31 | 1209 | else |
5544ad89 DJ |
1210 | step = process->resume->step; |
1211 | ||
32ca6d61 | 1212 | linux_resume_one_process (&process->head, step, process->resume->sig, NULL); |
c6ecbae5 | 1213 | |
5544ad89 DJ |
1214 | process->resume = NULL; |
1215 | } | |
1216 | ||
1217 | /* This function is called once per thread. We check the thread's resume | |
1218 | request, which will tell us whether to resume, step, or leave the thread | |
1219 | stopped; and what signal, if any, it should be sent. We queue any needed | |
1220 | signals, since we won't actually resume. We already have a pending event | |
1221 | to report, so we don't need to preserve any step requests; they should | |
1222 | be re-issued if necessary. */ | |
1223 | ||
1224 | static void | |
1225 | linux_queue_one_thread (struct inferior_list_entry *entry) | |
1226 | { | |
1227 | struct process_info *process; | |
1228 | struct thread_info *thread; | |
1229 | ||
1230 | thread = (struct thread_info *) entry; | |
1231 | process = get_thread_process (thread); | |
1232 | ||
1233 | if (process->resume->leave_stopped) | |
1234 | return; | |
1235 | ||
1236 | /* If we have a new signal, enqueue the signal. */ | |
1237 | if (process->resume->sig != 0) | |
1238 | { | |
1239 | struct pending_signals *p_sig; | |
1240 | p_sig = malloc (sizeof (*p_sig)); | |
1241 | p_sig->prev = process->pending_signals; | |
1242 | p_sig->signal = process->resume->sig; | |
32ca6d61 DJ |
1243 | memset (&p_sig->info, 0, sizeof (siginfo_t)); |
1244 | ||
1245 | /* If this is the same signal we were previously stopped by, | |
1246 | make sure to queue its siginfo. We can ignore the return | |
1247 | value of ptrace; if it fails, we'll skip | |
1248 | PTRACE_SETSIGINFO. */ | |
1249 | if (WIFSTOPPED (process->last_status) | |
1250 | && WSTOPSIG (process->last_status) == process->resume->sig) | |
1251 | ptrace (PTRACE_GETSIGINFO, process->lwpid, 0, &p_sig->info); | |
1252 | ||
5544ad89 DJ |
1253 | process->pending_signals = p_sig; |
1254 | } | |
1255 | ||
1256 | process->resume = NULL; | |
1257 | } | |
1258 | ||
1259 | /* Set DUMMY if this process has an interesting status pending. */ | |
1260 | static int | |
1261 | resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p) | |
1262 | { | |
1263 | struct process_info *process = (struct process_info *) entry; | |
1264 | ||
1265 | /* Processes which will not be resumed are not interesting, because | |
1266 | we might not wait for them next time through linux_wait. */ | |
1267 | if (process->resume->leave_stopped) | |
1268 | return 0; | |
1269 | ||
1270 | /* If this thread has a removed breakpoint, we won't have any | |
1271 | events to report later, so check now. check_removed_breakpoint | |
1272 | may clear status_pending_p. We avoid calling check_removed_breakpoint | |
1273 | for any thread that we are not otherwise going to resume - this | |
1274 | lets us preserve stopped status when two threads hit a breakpoint. | |
1275 | GDB removes the breakpoint to single-step a particular thread | |
1276 | past it, then re-inserts it and resumes all threads. We want | |
1277 | to report the second thread without resuming it in the interim. */ | |
1278 | if (process->status_pending_p) | |
1279 | check_removed_breakpoint (process); | |
1280 | ||
1281 | if (process->status_pending_p) | |
1282 | * (int *) flag_p = 1; | |
1283 | ||
1284 | return 0; | |
0d62e5e8 DJ |
1285 | } |
1286 | ||
1287 | static void | |
64386c31 | 1288 | linux_resume (struct thread_resume *resume_info) |
0d62e5e8 | 1289 | { |
5544ad89 | 1290 | int pending_flag; |
c6ecbae5 | 1291 | |
5544ad89 | 1292 | /* Yes, the use of a global here is rather ugly. */ |
64386c31 | 1293 | resume_ptr = resume_info; |
5544ad89 DJ |
1294 | |
1295 | for_each_inferior (&all_threads, linux_set_resume_request); | |
1296 | ||
1297 | /* If there is a thread which would otherwise be resumed, which | |
1298 | has a pending status, then don't resume any threads - we can just | |
1299 | report the pending status. Make sure to queue any signals | |
1300 | that would otherwise be sent. */ | |
1301 | pending_flag = 0; | |
1302 | find_inferior (&all_processes, resume_status_pending_p, &pending_flag); | |
1303 | ||
1304 | if (debug_threads) | |
1305 | { | |
1306 | if (pending_flag) | |
1307 | fprintf (stderr, "Not resuming, pending status\n"); | |
1308 | else | |
1309 | fprintf (stderr, "Resuming, no pending status\n"); | |
1310 | } | |
1311 | ||
1312 | if (pending_flag) | |
1313 | for_each_inferior (&all_threads, linux_queue_one_thread); | |
1314 | else | |
62ea82f5 DJ |
1315 | { |
1316 | block_async_io (); | |
1317 | enable_async_io (); | |
1318 | for_each_inferior (&all_threads, linux_continue_one_thread); | |
1319 | } | |
0d62e5e8 DJ |
1320 | } |
1321 | ||
1322 | #ifdef HAVE_LINUX_USRREGS | |
da6d8c04 DJ |
1323 | |
1324 | int | |
0a30fbc4 | 1325 | register_addr (int regnum) |
da6d8c04 DJ |
1326 | { |
1327 | int addr; | |
1328 | ||
2ec06d2e | 1329 | if (regnum < 0 || regnum >= the_low_target.num_regs) |
da6d8c04 DJ |
1330 | error ("Invalid register number %d.", regnum); |
1331 | ||
2ec06d2e | 1332 | addr = the_low_target.regmap[regnum]; |
da6d8c04 DJ |
1333 | |
1334 | return addr; | |
1335 | } | |
1336 | ||
58caa3dc | 1337 | /* Fetch one register. */ |
da6d8c04 DJ |
1338 | static void |
1339 | fetch_register (int regno) | |
1340 | { | |
1341 | CORE_ADDR regaddr; | |
48d93c75 | 1342 | int i, size; |
0d62e5e8 | 1343 | char *buf; |
da6d8c04 | 1344 | |
2ec06d2e | 1345 | if (regno >= the_low_target.num_regs) |
0a30fbc4 | 1346 | return; |
2ec06d2e | 1347 | if ((*the_low_target.cannot_fetch_register) (regno)) |
0a30fbc4 | 1348 | return; |
da6d8c04 | 1349 | |
0a30fbc4 DJ |
1350 | regaddr = register_addr (regno); |
1351 | if (regaddr == -1) | |
1352 | return; | |
48d93c75 UW |
1353 | size = (register_size (regno) + sizeof (PTRACE_XFER_TYPE) - 1) |
1354 | & - sizeof (PTRACE_XFER_TYPE); | |
1355 | buf = alloca (size); | |
1356 | for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE)) | |
da6d8c04 DJ |
1357 | { |
1358 | errno = 0; | |
0d62e5e8 | 1359 | *(PTRACE_XFER_TYPE *) (buf + i) = |
da6d8c04 DJ |
1360 | ptrace (PTRACE_PEEKUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, 0); |
1361 | regaddr += sizeof (PTRACE_XFER_TYPE); | |
1362 | if (errno != 0) | |
1363 | { | |
1364 | /* Warning, not error, in case we are attached; sometimes the | |
1365 | kernel doesn't let us at the registers. */ | |
1366 | char *err = strerror (errno); | |
1367 | char *msg = alloca (strlen (err) + 128); | |
1368 | sprintf (msg, "reading register %d: %s", regno, err); | |
1369 | error (msg); | |
1370 | goto error_exit; | |
1371 | } | |
1372 | } | |
5a1f5858 DJ |
1373 | if (the_low_target.left_pad_xfer |
1374 | && register_size (regno) < sizeof (PTRACE_XFER_TYPE)) | |
1375 | supply_register (regno, (buf + sizeof (PTRACE_XFER_TYPE) | |
1376 | - register_size (regno))); | |
1377 | else | |
1378 | supply_register (regno, buf); | |
0d62e5e8 | 1379 | |
da6d8c04 DJ |
1380 | error_exit:; |
1381 | } | |
1382 | ||
1383 | /* Fetch all registers, or just one, from the child process. */ | |
58caa3dc DJ |
1384 | static void |
1385 | usr_fetch_inferior_registers (int regno) | |
da6d8c04 DJ |
1386 | { |
1387 | if (regno == -1 || regno == 0) | |
2ec06d2e | 1388 | for (regno = 0; regno < the_low_target.num_regs; regno++) |
da6d8c04 DJ |
1389 | fetch_register (regno); |
1390 | else | |
1391 | fetch_register (regno); | |
1392 | } | |
1393 | ||
1394 | /* Store our register values back into the inferior. | |
1395 | If REGNO is -1, do this for all registers. | |
1396 | Otherwise, REGNO specifies which register (so we can save time). */ | |
58caa3dc DJ |
1397 | static void |
1398 | usr_store_inferior_registers (int regno) | |
da6d8c04 DJ |
1399 | { |
1400 | CORE_ADDR regaddr; | |
48d93c75 | 1401 | int i, size; |
0d62e5e8 | 1402 | char *buf; |
da6d8c04 DJ |
1403 | |
1404 | if (regno >= 0) | |
1405 | { | |
2ec06d2e | 1406 | if (regno >= the_low_target.num_regs) |
0a30fbc4 DJ |
1407 | return; |
1408 | ||
bc1e36ca | 1409 | if ((*the_low_target.cannot_store_register) (regno) == 1) |
0a30fbc4 DJ |
1410 | return; |
1411 | ||
1412 | regaddr = register_addr (regno); | |
1413 | if (regaddr == -1) | |
da6d8c04 | 1414 | return; |
da6d8c04 | 1415 | errno = 0; |
48d93c75 UW |
1416 | size = (register_size (regno) + sizeof (PTRACE_XFER_TYPE) - 1) |
1417 | & - sizeof (PTRACE_XFER_TYPE); | |
1418 | buf = alloca (size); | |
1419 | memset (buf, 0, size); | |
5a1f5858 DJ |
1420 | if (the_low_target.left_pad_xfer |
1421 | && register_size (regno) < sizeof (PTRACE_XFER_TYPE)) | |
1422 | collect_register (regno, (buf + sizeof (PTRACE_XFER_TYPE) | |
1423 | - register_size (regno))); | |
1424 | else | |
1425 | collect_register (regno, buf); | |
48d93c75 | 1426 | for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE)) |
da6d8c04 | 1427 | { |
0a30fbc4 DJ |
1428 | errno = 0; |
1429 | ptrace (PTRACE_POKEUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, | |
2ff29de4 | 1430 | *(PTRACE_XFER_TYPE *) (buf + i)); |
da6d8c04 DJ |
1431 | if (errno != 0) |
1432 | { | |
bc1e36ca DJ |
1433 | if ((*the_low_target.cannot_store_register) (regno) == 0) |
1434 | { | |
1435 | char *err = strerror (errno); | |
1436 | char *msg = alloca (strlen (err) + 128); | |
1437 | sprintf (msg, "writing register %d: %s", | |
1438 | regno, err); | |
1439 | error (msg); | |
1440 | return; | |
1441 | } | |
da6d8c04 | 1442 | } |
2ff29de4 | 1443 | regaddr += sizeof (PTRACE_XFER_TYPE); |
da6d8c04 | 1444 | } |
da6d8c04 DJ |
1445 | } |
1446 | else | |
2ec06d2e | 1447 | for (regno = 0; regno < the_low_target.num_regs; regno++) |
0d62e5e8 | 1448 | usr_store_inferior_registers (regno); |
da6d8c04 | 1449 | } |
58caa3dc DJ |
1450 | #endif /* HAVE_LINUX_USRREGS */ |
1451 | ||
1452 | ||
1453 | ||
1454 | #ifdef HAVE_LINUX_REGSETS | |
1455 | ||
1456 | static int | |
0d62e5e8 | 1457 | regsets_fetch_inferior_registers () |
58caa3dc DJ |
1458 | { |
1459 | struct regset_info *regset; | |
e9d25b98 | 1460 | int saw_general_regs = 0; |
58caa3dc DJ |
1461 | |
1462 | regset = target_regsets; | |
1463 | ||
1464 | while (regset->size >= 0) | |
1465 | { | |
1466 | void *buf; | |
1467 | int res; | |
1468 | ||
1469 | if (regset->size == 0) | |
1470 | { | |
1471 | regset ++; | |
1472 | continue; | |
1473 | } | |
1474 | ||
1475 | buf = malloc (regset->size); | |
d06f167a | 1476 | res = ptrace (regset->get_request, inferior_pid, 0, buf); |
58caa3dc DJ |
1477 | if (res < 0) |
1478 | { | |
1479 | if (errno == EIO) | |
1480 | { | |
1481 | /* If we get EIO on the first regset, do not try regsets again. | |
1482 | If we get EIO on a later regset, disable that regset. */ | |
1483 | if (regset == target_regsets) | |
1484 | { | |
1485 | use_regsets_p = 0; | |
1486 | return -1; | |
1487 | } | |
1488 | else | |
1489 | { | |
1490 | regset->size = 0; | |
1491 | continue; | |
1492 | } | |
1493 | } | |
1494 | else | |
1495 | { | |
0d62e5e8 | 1496 | char s[256]; |
a1928bad | 1497 | sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%ld", |
0d62e5e8 DJ |
1498 | inferior_pid); |
1499 | perror (s); | |
58caa3dc DJ |
1500 | } |
1501 | } | |
e9d25b98 DJ |
1502 | else if (regset->type == GENERAL_REGS) |
1503 | saw_general_regs = 1; | |
58caa3dc DJ |
1504 | regset->store_function (buf); |
1505 | regset ++; | |
1506 | } | |
e9d25b98 DJ |
1507 | if (saw_general_regs) |
1508 | return 0; | |
1509 | else | |
1510 | return 1; | |
58caa3dc DJ |
1511 | } |
1512 | ||
1513 | static int | |
0d62e5e8 | 1514 | regsets_store_inferior_registers () |
58caa3dc DJ |
1515 | { |
1516 | struct regset_info *regset; | |
e9d25b98 | 1517 | int saw_general_regs = 0; |
58caa3dc DJ |
1518 | |
1519 | regset = target_regsets; | |
1520 | ||
1521 | while (regset->size >= 0) | |
1522 | { | |
1523 | void *buf; | |
1524 | int res; | |
1525 | ||
1526 | if (regset->size == 0) | |
1527 | { | |
1528 | regset ++; | |
1529 | continue; | |
1530 | } | |
1531 | ||
1532 | buf = malloc (regset->size); | |
545587ee DJ |
1533 | |
1534 | /* First fill the buffer with the current register set contents, | |
1535 | in case there are any items in the kernel's regset that are | |
1536 | not in gdbserver's regcache. */ | |
1537 | res = ptrace (regset->get_request, inferior_pid, 0, buf); | |
1538 | ||
1539 | if (res == 0) | |
1540 | { | |
1541 | /* Then overlay our cached registers on that. */ | |
1542 | regset->fill_function (buf); | |
1543 | ||
1544 | /* Only now do we write the register set. */ | |
1545 | res = ptrace (regset->set_request, inferior_pid, 0, buf); | |
1546 | } | |
1547 | ||
58caa3dc DJ |
1548 | if (res < 0) |
1549 | { | |
1550 | if (errno == EIO) | |
1551 | { | |
1552 | /* If we get EIO on the first regset, do not try regsets again. | |
1553 | If we get EIO on a later regset, disable that regset. */ | |
1554 | if (regset == target_regsets) | |
1555 | { | |
1556 | use_regsets_p = 0; | |
1557 | return -1; | |
1558 | } | |
1559 | else | |
1560 | { | |
1561 | regset->size = 0; | |
1562 | continue; | |
1563 | } | |
1564 | } | |
1565 | else | |
1566 | { | |
ce3a066d | 1567 | perror ("Warning: ptrace(regsets_store_inferior_registers)"); |
58caa3dc DJ |
1568 | } |
1569 | } | |
e9d25b98 DJ |
1570 | else if (regset->type == GENERAL_REGS) |
1571 | saw_general_regs = 1; | |
58caa3dc | 1572 | regset ++; |
09ec9b38 | 1573 | free (buf); |
58caa3dc | 1574 | } |
e9d25b98 DJ |
1575 | if (saw_general_regs) |
1576 | return 0; | |
1577 | else | |
1578 | return 1; | |
ce3a066d | 1579 | return 0; |
58caa3dc DJ |
1580 | } |
1581 | ||
1582 | #endif /* HAVE_LINUX_REGSETS */ | |
1583 | ||
1584 | ||
1585 | void | |
ce3a066d | 1586 | linux_fetch_registers (int regno) |
58caa3dc DJ |
1587 | { |
1588 | #ifdef HAVE_LINUX_REGSETS | |
1589 | if (use_regsets_p) | |
1590 | { | |
1591 | if (regsets_fetch_inferior_registers () == 0) | |
1592 | return; | |
1593 | } | |
1594 | #endif | |
1595 | #ifdef HAVE_LINUX_USRREGS | |
1596 | usr_fetch_inferior_registers (regno); | |
1597 | #endif | |
1598 | } | |
1599 | ||
1600 | void | |
ce3a066d | 1601 | linux_store_registers (int regno) |
58caa3dc DJ |
1602 | { |
1603 | #ifdef HAVE_LINUX_REGSETS | |
1604 | if (use_regsets_p) | |
1605 | { | |
1606 | if (regsets_store_inferior_registers () == 0) | |
1607 | return; | |
1608 | } | |
1609 | #endif | |
1610 | #ifdef HAVE_LINUX_USRREGS | |
1611 | usr_store_inferior_registers (regno); | |
1612 | #endif | |
1613 | } | |
1614 | ||
da6d8c04 | 1615 | |
da6d8c04 DJ |
1616 | /* Copy LEN bytes from inferior's memory starting at MEMADDR |
1617 | to debugger memory starting at MYADDR. */ | |
1618 | ||
c3e735a6 | 1619 | static int |
f450004a | 1620 | linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len) |
da6d8c04 DJ |
1621 | { |
1622 | register int i; | |
1623 | /* Round starting address down to longword boundary. */ | |
1624 | register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
1625 | /* Round ending address up; get number of longwords that makes. */ | |
aa691b87 RM |
1626 | register int count |
1627 | = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) | |
da6d8c04 DJ |
1628 | / sizeof (PTRACE_XFER_TYPE); |
1629 | /* Allocate buffer of that many longwords. */ | |
aa691b87 | 1630 | register PTRACE_XFER_TYPE *buffer |
da6d8c04 | 1631 | = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE)); |
fd462a61 DJ |
1632 | int fd; |
1633 | char filename[64]; | |
1634 | ||
1635 | /* Try using /proc. Don't bother for one word. */ | |
1636 | if (len >= 3 * sizeof (long)) | |
1637 | { | |
1638 | /* We could keep this file open and cache it - possibly one per | |
1639 | thread. That requires some juggling, but is even faster. */ | |
1640 | sprintf (filename, "/proc/%ld/mem", inferior_pid); | |
1641 | fd = open (filename, O_RDONLY | O_LARGEFILE); | |
1642 | if (fd == -1) | |
1643 | goto no_proc; | |
1644 | ||
1645 | /* If pread64 is available, use it. It's faster if the kernel | |
1646 | supports it (only one syscall), and it's 64-bit safe even on | |
1647 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
1648 | application). */ | |
1649 | #ifdef HAVE_PREAD64 | |
1650 | if (pread64 (fd, myaddr, len, memaddr) != len) | |
1651 | #else | |
1652 | if (lseek (fd, memaddr, SEEK_SET) == -1 || read (fd, memaddr, len) != len) | |
1653 | #endif | |
1654 | { | |
1655 | close (fd); | |
1656 | goto no_proc; | |
1657 | } | |
1658 | ||
1659 | close (fd); | |
1660 | return 0; | |
1661 | } | |
da6d8c04 | 1662 | |
fd462a61 | 1663 | no_proc: |
da6d8c04 DJ |
1664 | /* Read all the longwords */ |
1665 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
1666 | { | |
c3e735a6 | 1667 | errno = 0; |
d844cde6 | 1668 | buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, 0); |
c3e735a6 DJ |
1669 | if (errno) |
1670 | return errno; | |
da6d8c04 DJ |
1671 | } |
1672 | ||
1673 | /* Copy appropriate bytes out of the buffer. */ | |
1674 | memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), len); | |
c3e735a6 DJ |
1675 | |
1676 | return 0; | |
da6d8c04 DJ |
1677 | } |
1678 | ||
1679 | /* Copy LEN bytes of data from debugger memory at MYADDR | |
1680 | to inferior's memory at MEMADDR. | |
1681 | On failure (cannot write the inferior) | |
1682 | returns the value of errno. */ | |
1683 | ||
ce3a066d | 1684 | static int |
f450004a | 1685 | linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len) |
da6d8c04 DJ |
1686 | { |
1687 | register int i; | |
1688 | /* Round starting address down to longword boundary. */ | |
1689 | register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
1690 | /* Round ending address up; get number of longwords that makes. */ | |
1691 | register int count | |
1692 | = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) / sizeof (PTRACE_XFER_TYPE); | |
1693 | /* Allocate buffer of that many longwords. */ | |
1694 | register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE)); | |
1695 | extern int errno; | |
1696 | ||
0d62e5e8 DJ |
1697 | if (debug_threads) |
1698 | { | |
1699 | fprintf (stderr, "Writing %02x to %08lx\n", (unsigned)myaddr[0], (long)memaddr); | |
1700 | } | |
1701 | ||
da6d8c04 DJ |
1702 | /* Fill start and end extra bytes of buffer with existing memory data. */ |
1703 | ||
d844cde6 DJ |
1704 | buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid, |
1705 | (PTRACE_ARG3_TYPE) addr, 0); | |
da6d8c04 DJ |
1706 | |
1707 | if (count > 1) | |
1708 | { | |
1709 | buffer[count - 1] | |
1710 | = ptrace (PTRACE_PEEKTEXT, inferior_pid, | |
d844cde6 DJ |
1711 | (PTRACE_ARG3_TYPE) (addr + (count - 1) |
1712 | * sizeof (PTRACE_XFER_TYPE)), | |
1713 | 0); | |
da6d8c04 DJ |
1714 | } |
1715 | ||
1716 | /* Copy data to be written over corresponding part of buffer */ | |
1717 | ||
1718 | memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), myaddr, len); | |
1719 | ||
1720 | /* Write the entire buffer. */ | |
1721 | ||
1722 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
1723 | { | |
1724 | errno = 0; | |
d844cde6 | 1725 | ptrace (PTRACE_POKETEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, buffer[i]); |
da6d8c04 DJ |
1726 | if (errno) |
1727 | return errno; | |
1728 | } | |
1729 | ||
1730 | return 0; | |
1731 | } | |
2f2893d9 | 1732 | |
24a09b5f DJ |
1733 | static int linux_supports_tracefork_flag; |
1734 | ||
51c2684e | 1735 | /* Helper functions for linux_test_for_tracefork, called via clone (). */ |
24a09b5f | 1736 | |
51c2684e DJ |
1737 | static int |
1738 | linux_tracefork_grandchild (void *arg) | |
1739 | { | |
1740 | _exit (0); | |
1741 | } | |
1742 | ||
1743 | static int | |
1744 | linux_tracefork_child (void *arg) | |
24a09b5f DJ |
1745 | { |
1746 | ptrace (PTRACE_TRACEME, 0, 0, 0); | |
1747 | kill (getpid (), SIGSTOP); | |
51c2684e | 1748 | clone (linux_tracefork_grandchild, arg, CLONE_VM | SIGCHLD, NULL); |
24a09b5f DJ |
1749 | _exit (0); |
1750 | } | |
1751 | ||
1752 | /* Wrapper function for waitpid which handles EINTR. */ | |
1753 | ||
1754 | static int | |
1755 | my_waitpid (int pid, int *status, int flags) | |
1756 | { | |
1757 | int ret; | |
1758 | do | |
1759 | { | |
1760 | ret = waitpid (pid, status, flags); | |
1761 | } | |
1762 | while (ret == -1 && errno == EINTR); | |
1763 | ||
1764 | return ret; | |
1765 | } | |
1766 | ||
1767 | /* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. Make | |
1768 | sure that we can enable the option, and that it had the desired | |
1769 | effect. */ | |
1770 | ||
1771 | static void | |
1772 | linux_test_for_tracefork (void) | |
1773 | { | |
1774 | int child_pid, ret, status; | |
1775 | long second_pid; | |
51c2684e | 1776 | char *stack = malloc (8192); |
24a09b5f DJ |
1777 | |
1778 | linux_supports_tracefork_flag = 0; | |
1779 | ||
51c2684e DJ |
1780 | /* Use CLONE_VM instead of fork, to support uClinux (no MMU). */ |
1781 | child_pid = clone (linux_tracefork_child, stack + 2048, | |
1782 | CLONE_VM | SIGCHLD, stack + 6144); | |
24a09b5f | 1783 | if (child_pid == -1) |
51c2684e | 1784 | perror_with_name ("clone"); |
24a09b5f DJ |
1785 | |
1786 | ret = my_waitpid (child_pid, &status, 0); | |
1787 | if (ret == -1) | |
1788 | perror_with_name ("waitpid"); | |
1789 | else if (ret != child_pid) | |
1790 | error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret); | |
1791 | if (! WIFSTOPPED (status)) | |
1792 | error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status); | |
1793 | ||
1794 | ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK); | |
1795 | if (ret != 0) | |
1796 | { | |
1797 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); | |
1798 | if (ret != 0) | |
1799 | { | |
1800 | warning ("linux_test_for_tracefork: failed to kill child"); | |
1801 | return; | |
1802 | } | |
1803 | ||
1804 | ret = my_waitpid (child_pid, &status, 0); | |
1805 | if (ret != child_pid) | |
1806 | warning ("linux_test_for_tracefork: failed to wait for killed child"); | |
1807 | else if (!WIFSIGNALED (status)) | |
1808 | warning ("linux_test_for_tracefork: unexpected wait status 0x%x from " | |
1809 | "killed child", status); | |
1810 | ||
1811 | return; | |
1812 | } | |
1813 | ||
1814 | ret = ptrace (PTRACE_CONT, child_pid, 0, 0); | |
1815 | if (ret != 0) | |
1816 | warning ("linux_test_for_tracefork: failed to resume child"); | |
1817 | ||
1818 | ret = my_waitpid (child_pid, &status, 0); | |
1819 | ||
1820 | if (ret == child_pid && WIFSTOPPED (status) | |
1821 | && status >> 16 == PTRACE_EVENT_FORK) | |
1822 | { | |
1823 | second_pid = 0; | |
1824 | ret = ptrace (PTRACE_GETEVENTMSG, child_pid, 0, &second_pid); | |
1825 | if (ret == 0 && second_pid != 0) | |
1826 | { | |
1827 | int second_status; | |
1828 | ||
1829 | linux_supports_tracefork_flag = 1; | |
1830 | my_waitpid (second_pid, &second_status, 0); | |
1831 | ret = ptrace (PTRACE_KILL, second_pid, 0, 0); | |
1832 | if (ret != 0) | |
1833 | warning ("linux_test_for_tracefork: failed to kill second child"); | |
1834 | my_waitpid (second_pid, &status, 0); | |
1835 | } | |
1836 | } | |
1837 | else | |
1838 | warning ("linux_test_for_tracefork: unexpected result from waitpid " | |
1839 | "(%d, status 0x%x)", ret, status); | |
1840 | ||
1841 | do | |
1842 | { | |
1843 | ret = ptrace (PTRACE_KILL, child_pid, 0, 0); | |
1844 | if (ret != 0) | |
1845 | warning ("linux_test_for_tracefork: failed to kill child"); | |
1846 | my_waitpid (child_pid, &status, 0); | |
1847 | } | |
1848 | while (WIFSTOPPED (status)); | |
51c2684e DJ |
1849 | |
1850 | free (stack); | |
24a09b5f DJ |
1851 | } |
1852 | ||
1853 | ||
2f2893d9 DJ |
1854 | static void |
1855 | linux_look_up_symbols (void) | |
1856 | { | |
0d62e5e8 | 1857 | #ifdef USE_THREAD_DB |
24a09b5f | 1858 | if (thread_db_active) |
0d62e5e8 DJ |
1859 | return; |
1860 | ||
24a09b5f | 1861 | thread_db_active = thread_db_init (!linux_supports_tracefork_flag); |
0d62e5e8 DJ |
1862 | #endif |
1863 | } | |
1864 | ||
e5379b03 | 1865 | static void |
ef57601b | 1866 | linux_request_interrupt (void) |
e5379b03 | 1867 | { |
a1928bad | 1868 | extern unsigned long signal_pid; |
e5379b03 | 1869 | |
d592fa2f | 1870 | if (cont_thread != 0 && cont_thread != -1) |
e5379b03 DJ |
1871 | { |
1872 | struct process_info *process; | |
1873 | ||
1874 | process = get_thread_process (current_inferior); | |
ef57601b | 1875 | kill_lwp (process->lwpid, SIGINT); |
e5379b03 DJ |
1876 | } |
1877 | else | |
ef57601b | 1878 | kill_lwp (signal_pid, SIGINT); |
e5379b03 DJ |
1879 | } |
1880 | ||
aa691b87 RM |
1881 | /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET |
1882 | to debugger memory starting at MYADDR. */ | |
1883 | ||
1884 | static int | |
f450004a | 1885 | linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len) |
aa691b87 RM |
1886 | { |
1887 | char filename[PATH_MAX]; | |
1888 | int fd, n; | |
1889 | ||
a1928bad | 1890 | snprintf (filename, sizeof filename, "/proc/%ld/auxv", inferior_pid); |
aa691b87 RM |
1891 | |
1892 | fd = open (filename, O_RDONLY); | |
1893 | if (fd < 0) | |
1894 | return -1; | |
1895 | ||
1896 | if (offset != (CORE_ADDR) 0 | |
1897 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
1898 | n = -1; | |
1899 | else | |
1900 | n = read (fd, myaddr, len); | |
1901 | ||
1902 | close (fd); | |
1903 | ||
1904 | return n; | |
1905 | } | |
1906 | ||
e013ee27 OF |
1907 | /* These watchpoint related wrapper functions simply pass on the function call |
1908 | if the target has registered a corresponding function. */ | |
1909 | ||
1910 | static int | |
1911 | linux_insert_watchpoint (char type, CORE_ADDR addr, int len) | |
1912 | { | |
1913 | if (the_low_target.insert_watchpoint != NULL) | |
1914 | return the_low_target.insert_watchpoint (type, addr, len); | |
1915 | else | |
1916 | /* Unsupported (see target.h). */ | |
1917 | return 1; | |
1918 | } | |
1919 | ||
1920 | static int | |
1921 | linux_remove_watchpoint (char type, CORE_ADDR addr, int len) | |
1922 | { | |
1923 | if (the_low_target.remove_watchpoint != NULL) | |
1924 | return the_low_target.remove_watchpoint (type, addr, len); | |
1925 | else | |
1926 | /* Unsupported (see target.h). */ | |
1927 | return 1; | |
1928 | } | |
1929 | ||
1930 | static int | |
1931 | linux_stopped_by_watchpoint (void) | |
1932 | { | |
1933 | if (the_low_target.stopped_by_watchpoint != NULL) | |
1934 | return the_low_target.stopped_by_watchpoint (); | |
1935 | else | |
1936 | return 0; | |
1937 | } | |
1938 | ||
1939 | static CORE_ADDR | |
1940 | linux_stopped_data_address (void) | |
1941 | { | |
1942 | if (the_low_target.stopped_data_address != NULL) | |
1943 | return the_low_target.stopped_data_address (); | |
1944 | else | |
1945 | return 0; | |
1946 | } | |
1947 | ||
42c81e2a | 1948 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) |
52fb6437 NS |
1949 | #if defined(__mcoldfire__) |
1950 | /* These should really be defined in the kernel's ptrace.h header. */ | |
1951 | #define PT_TEXT_ADDR 49*4 | |
1952 | #define PT_DATA_ADDR 50*4 | |
1953 | #define PT_TEXT_END_ADDR 51*4 | |
1954 | #endif | |
1955 | ||
1956 | /* Under uClinux, programs are loaded at non-zero offsets, which we need | |
1957 | to tell gdb about. */ | |
1958 | ||
1959 | static int | |
1960 | linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p) | |
1961 | { | |
1962 | #if defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) && defined(PT_TEXT_END_ADDR) | |
1963 | unsigned long text, text_end, data; | |
1964 | int pid = get_thread_process (current_inferior)->head.id; | |
1965 | ||
1966 | errno = 0; | |
1967 | ||
1968 | text = ptrace (PTRACE_PEEKUSER, pid, (long)PT_TEXT_ADDR, 0); | |
1969 | text_end = ptrace (PTRACE_PEEKUSER, pid, (long)PT_TEXT_END_ADDR, 0); | |
1970 | data = ptrace (PTRACE_PEEKUSER, pid, (long)PT_DATA_ADDR, 0); | |
1971 | ||
1972 | if (errno == 0) | |
1973 | { | |
1974 | /* Both text and data offsets produced at compile-time (and so | |
1975 | used by gdb) are relative to the beginning of the program, | |
1976 | with the data segment immediately following the text segment. | |
1977 | However, the actual runtime layout in memory may put the data | |
1978 | somewhere else, so when we send gdb a data base-address, we | |
1979 | use the real data base address and subtract the compile-time | |
1980 | data base-address from it (which is just the length of the | |
1981 | text segment). BSS immediately follows data in both | |
1982 | cases. */ | |
1983 | *text_p = text; | |
1984 | *data_p = data - (text_end - text); | |
1985 | ||
1986 | return 1; | |
1987 | } | |
1988 | #endif | |
1989 | return 0; | |
1990 | } | |
1991 | #endif | |
1992 | ||
23181151 DJ |
1993 | static const char * |
1994 | linux_arch_string (void) | |
1995 | { | |
1996 | return the_low_target.arch_string; | |
1997 | } | |
1998 | ||
ce3a066d DJ |
1999 | static struct target_ops linux_target_ops = { |
2000 | linux_create_inferior, | |
2001 | linux_attach, | |
2002 | linux_kill, | |
6ad8ae5c | 2003 | linux_detach, |
444d6139 | 2004 | linux_join, |
ce3a066d DJ |
2005 | linux_thread_alive, |
2006 | linux_resume, | |
2007 | linux_wait, | |
2008 | linux_fetch_registers, | |
2009 | linux_store_registers, | |
2010 | linux_read_memory, | |
2011 | linux_write_memory, | |
2f2893d9 | 2012 | linux_look_up_symbols, |
ef57601b | 2013 | linux_request_interrupt, |
aa691b87 | 2014 | linux_read_auxv, |
e013ee27 OF |
2015 | linux_insert_watchpoint, |
2016 | linux_remove_watchpoint, | |
2017 | linux_stopped_by_watchpoint, | |
2018 | linux_stopped_data_address, | |
42c81e2a | 2019 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) |
52fb6437 | 2020 | linux_read_offsets, |
dae5f5cf DJ |
2021 | #else |
2022 | NULL, | |
2023 | #endif | |
2024 | #ifdef USE_THREAD_DB | |
2025 | thread_db_get_tls_address, | |
2026 | #else | |
2027 | NULL, | |
52fb6437 | 2028 | #endif |
23181151 | 2029 | linux_arch_string, |
ce3a066d DJ |
2030 | }; |
2031 | ||
0d62e5e8 DJ |
2032 | static void |
2033 | linux_init_signals () | |
2034 | { | |
2035 | /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads | |
2036 | to find what the cancel signal actually is. */ | |
254787d4 | 2037 | signal (__SIGRTMIN+1, SIG_IGN); |
0d62e5e8 DJ |
2038 | } |
2039 | ||
da6d8c04 DJ |
2040 | void |
2041 | initialize_low (void) | |
2042 | { | |
24a09b5f | 2043 | thread_db_active = 0; |
ce3a066d | 2044 | set_target_ops (&linux_target_ops); |
611cb4a5 DJ |
2045 | set_breakpoint_data (the_low_target.breakpoint, |
2046 | the_low_target.breakpoint_len); | |
0a30fbc4 | 2047 | init_registers (); |
0d62e5e8 | 2048 | linux_init_signals (); |
24a09b5f | 2049 | linux_test_for_tracefork (); |
da6d8c04 | 2050 | } |