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