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1 | /* Low level interface to ptrace, for the remote server for GDB. | |
2 | Copyright (C) 1995-2016 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of GDB. | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 3 of the License, or | |
9 | (at your option) any later version. | |
10 | ||
11 | This program is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | |
18 | ||
19 | #include "server.h" | |
20 | #include "linux-low.h" | |
21 | #include "nat/linux-osdata.h" | |
22 | #include "agent.h" | |
23 | #include "tdesc.h" | |
24 | #include "rsp-low.h" | |
25 | ||
26 | #include "nat/linux-nat.h" | |
27 | #include "nat/linux-waitpid.h" | |
28 | #include "gdb_wait.h" | |
29 | #include "nat/gdb_ptrace.h" | |
30 | #include "nat/linux-ptrace.h" | |
31 | #include "nat/linux-procfs.h" | |
32 | #include "nat/linux-personality.h" | |
33 | #include <signal.h> | |
34 | #include <sys/ioctl.h> | |
35 | #include <fcntl.h> | |
36 | #include <unistd.h> | |
37 | #include <sys/syscall.h> | |
38 | #include <sched.h> | |
39 | #include <ctype.h> | |
40 | #include <pwd.h> | |
41 | #include <sys/types.h> | |
42 | #include <dirent.h> | |
43 | #include <sys/stat.h> | |
44 | #include <sys/vfs.h> | |
45 | #include <sys/uio.h> | |
46 | #include "filestuff.h" | |
47 | #include "tracepoint.h" | |
48 | #include "hostio.h" | |
49 | #include <inttypes.h> | |
50 | #ifndef ELFMAG0 | |
51 | /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h | |
52 | then ELFMAG0 will have been defined. If it didn't get included by | |
53 | gdb_proc_service.h then including it will likely introduce a duplicate | |
54 | definition of elf_fpregset_t. */ | |
55 | #include <elf.h> | |
56 | #endif | |
57 | #include "nat/linux-namespaces.h" | |
58 | ||
59 | #ifndef SPUFS_MAGIC | |
60 | #define SPUFS_MAGIC 0x23c9b64e | |
61 | #endif | |
62 | ||
63 | #ifdef HAVE_PERSONALITY | |
64 | # include <sys/personality.h> | |
65 | # if !HAVE_DECL_ADDR_NO_RANDOMIZE | |
66 | # define ADDR_NO_RANDOMIZE 0x0040000 | |
67 | # endif | |
68 | #endif | |
69 | ||
70 | #ifndef O_LARGEFILE | |
71 | #define O_LARGEFILE 0 | |
72 | #endif | |
73 | ||
74 | /* Some targets did not define these ptrace constants from the start, | |
75 | so gdbserver defines them locally here. In the future, these may | |
76 | be removed after they are added to asm/ptrace.h. */ | |
77 | #if !(defined(PT_TEXT_ADDR) \ | |
78 | || defined(PT_DATA_ADDR) \ | |
79 | || defined(PT_TEXT_END_ADDR)) | |
80 | #if defined(__mcoldfire__) | |
81 | /* These are still undefined in 3.10 kernels. */ | |
82 | #define PT_TEXT_ADDR 49*4 | |
83 | #define PT_DATA_ADDR 50*4 | |
84 | #define PT_TEXT_END_ADDR 51*4 | |
85 | /* BFIN already defines these since at least 2.6.32 kernels. */ | |
86 | #elif defined(BFIN) | |
87 | #define PT_TEXT_ADDR 220 | |
88 | #define PT_TEXT_END_ADDR 224 | |
89 | #define PT_DATA_ADDR 228 | |
90 | /* These are still undefined in 3.10 kernels. */ | |
91 | #elif defined(__TMS320C6X__) | |
92 | #define PT_TEXT_ADDR (0x10000*4) | |
93 | #define PT_DATA_ADDR (0x10004*4) | |
94 | #define PT_TEXT_END_ADDR (0x10008*4) | |
95 | #endif | |
96 | #endif | |
97 | ||
98 | #ifdef HAVE_LINUX_BTRACE | |
99 | # include "nat/linux-btrace.h" | |
100 | # include "btrace-common.h" | |
101 | #endif | |
102 | ||
103 | #ifndef HAVE_ELF32_AUXV_T | |
104 | /* Copied from glibc's elf.h. */ | |
105 | typedef struct | |
106 | { | |
107 | uint32_t a_type; /* Entry type */ | |
108 | union | |
109 | { | |
110 | uint32_t a_val; /* Integer value */ | |
111 | /* We use to have pointer elements added here. We cannot do that, | |
112 | though, since it does not work when using 32-bit definitions | |
113 | on 64-bit platforms and vice versa. */ | |
114 | } a_un; | |
115 | } Elf32_auxv_t; | |
116 | #endif | |
117 | ||
118 | #ifndef HAVE_ELF64_AUXV_T | |
119 | /* Copied from glibc's elf.h. */ | |
120 | typedef struct | |
121 | { | |
122 | uint64_t a_type; /* Entry type */ | |
123 | union | |
124 | { | |
125 | uint64_t a_val; /* Integer value */ | |
126 | /* We use to have pointer elements added here. We cannot do that, | |
127 | though, since it does not work when using 32-bit definitions | |
128 | on 64-bit platforms and vice versa. */ | |
129 | } a_un; | |
130 | } Elf64_auxv_t; | |
131 | #endif | |
132 | ||
133 | /* Does the current host support PTRACE_GETREGSET? */ | |
134 | int have_ptrace_getregset = -1; | |
135 | ||
136 | /* LWP accessors. */ | |
137 | ||
138 | /* See nat/linux-nat.h. */ | |
139 | ||
140 | ptid_t | |
141 | ptid_of_lwp (struct lwp_info *lwp) | |
142 | { | |
143 | return ptid_of (get_lwp_thread (lwp)); | |
144 | } | |
145 | ||
146 | /* See nat/linux-nat.h. */ | |
147 | ||
148 | void | |
149 | lwp_set_arch_private_info (struct lwp_info *lwp, | |
150 | struct arch_lwp_info *info) | |
151 | { | |
152 | lwp->arch_private = info; | |
153 | } | |
154 | ||
155 | /* See nat/linux-nat.h. */ | |
156 | ||
157 | struct arch_lwp_info * | |
158 | lwp_arch_private_info (struct lwp_info *lwp) | |
159 | { | |
160 | return lwp->arch_private; | |
161 | } | |
162 | ||
163 | /* See nat/linux-nat.h. */ | |
164 | ||
165 | int | |
166 | lwp_is_stopped (struct lwp_info *lwp) | |
167 | { | |
168 | return lwp->stopped; | |
169 | } | |
170 | ||
171 | /* See nat/linux-nat.h. */ | |
172 | ||
173 | enum target_stop_reason | |
174 | lwp_stop_reason (struct lwp_info *lwp) | |
175 | { | |
176 | return lwp->stop_reason; | |
177 | } | |
178 | ||
179 | /* A list of all unknown processes which receive stop signals. Some | |
180 | other process will presumably claim each of these as forked | |
181 | children momentarily. */ | |
182 | ||
183 | struct simple_pid_list | |
184 | { | |
185 | /* The process ID. */ | |
186 | int pid; | |
187 | ||
188 | /* The status as reported by waitpid. */ | |
189 | int status; | |
190 | ||
191 | /* Next in chain. */ | |
192 | struct simple_pid_list *next; | |
193 | }; | |
194 | struct simple_pid_list *stopped_pids; | |
195 | ||
196 | /* Trivial list manipulation functions to keep track of a list of new | |
197 | stopped processes. */ | |
198 | ||
199 | static void | |
200 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) | |
201 | { | |
202 | struct simple_pid_list *new_pid = XNEW (struct simple_pid_list); | |
203 | ||
204 | new_pid->pid = pid; | |
205 | new_pid->status = status; | |
206 | new_pid->next = *listp; | |
207 | *listp = new_pid; | |
208 | } | |
209 | ||
210 | static int | |
211 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) | |
212 | { | |
213 | struct simple_pid_list **p; | |
214 | ||
215 | for (p = listp; *p != NULL; p = &(*p)->next) | |
216 | if ((*p)->pid == pid) | |
217 | { | |
218 | struct simple_pid_list *next = (*p)->next; | |
219 | ||
220 | *statusp = (*p)->status; | |
221 | xfree (*p); | |
222 | *p = next; | |
223 | return 1; | |
224 | } | |
225 | return 0; | |
226 | } | |
227 | ||
228 | enum stopping_threads_kind | |
229 | { | |
230 | /* Not stopping threads presently. */ | |
231 | NOT_STOPPING_THREADS, | |
232 | ||
233 | /* Stopping threads. */ | |
234 | STOPPING_THREADS, | |
235 | ||
236 | /* Stopping and suspending threads. */ | |
237 | STOPPING_AND_SUSPENDING_THREADS | |
238 | }; | |
239 | ||
240 | /* This is set while stop_all_lwps is in effect. */ | |
241 | enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS; | |
242 | ||
243 | /* FIXME make into a target method? */ | |
244 | int using_threads = 1; | |
245 | ||
246 | /* True if we're presently stabilizing threads (moving them out of | |
247 | jump pads). */ | |
248 | static int stabilizing_threads; | |
249 | ||
250 | static void linux_resume_one_lwp (struct lwp_info *lwp, | |
251 | int step, int signal, siginfo_t *info); | |
252 | static void linux_resume (struct thread_resume *resume_info, size_t n); | |
253 | static void stop_all_lwps (int suspend, struct lwp_info *except); | |
254 | static void unstop_all_lwps (int unsuspend, struct lwp_info *except); | |
255 | static void unsuspend_all_lwps (struct lwp_info *except); | |
256 | static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid, | |
257 | int *wstat, int options); | |
258 | static int linux_wait_for_event (ptid_t ptid, int *wstat, int options); | |
259 | static struct lwp_info *add_lwp (ptid_t ptid); | |
260 | static void linux_mourn (struct process_info *process); | |
261 | static int linux_stopped_by_watchpoint (void); | |
262 | static void mark_lwp_dead (struct lwp_info *lwp, int wstat); | |
263 | static int lwp_is_marked_dead (struct lwp_info *lwp); | |
264 | static void proceed_all_lwps (void); | |
265 | static int finish_step_over (struct lwp_info *lwp); | |
266 | static int kill_lwp (unsigned long lwpid, int signo); | |
267 | static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info); | |
268 | static void complete_ongoing_step_over (void); | |
269 | static int linux_low_ptrace_options (int attached); | |
270 | static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp); | |
271 | static int proceed_one_lwp (struct inferior_list_entry *entry, void *except); | |
272 | ||
273 | /* When the event-loop is doing a step-over, this points at the thread | |
274 | being stepped. */ | |
275 | ptid_t step_over_bkpt; | |
276 | ||
277 | /* True if the low target can hardware single-step. */ | |
278 | ||
279 | static int | |
280 | can_hardware_single_step (void) | |
281 | { | |
282 | if (the_low_target.supports_hardware_single_step != NULL) | |
283 | return the_low_target.supports_hardware_single_step (); | |
284 | else | |
285 | return 0; | |
286 | } | |
287 | ||
288 | /* True if the low target can software single-step. Such targets | |
289 | implement the GET_NEXT_PCS callback. */ | |
290 | ||
291 | static int | |
292 | can_software_single_step (void) | |
293 | { | |
294 | return (the_low_target.get_next_pcs != NULL); | |
295 | } | |
296 | ||
297 | /* True if the low target supports memory breakpoints. If so, we'll | |
298 | have a GET_PC implementation. */ | |
299 | ||
300 | static int | |
301 | supports_breakpoints (void) | |
302 | { | |
303 | return (the_low_target.get_pc != NULL); | |
304 | } | |
305 | ||
306 | /* Returns true if this target can support fast tracepoints. This | |
307 | does not mean that the in-process agent has been loaded in the | |
308 | inferior. */ | |
309 | ||
310 | static int | |
311 | supports_fast_tracepoints (void) | |
312 | { | |
313 | return the_low_target.install_fast_tracepoint_jump_pad != NULL; | |
314 | } | |
315 | ||
316 | /* True if LWP is stopped in its stepping range. */ | |
317 | ||
318 | static int | |
319 | lwp_in_step_range (struct lwp_info *lwp) | |
320 | { | |
321 | CORE_ADDR pc = lwp->stop_pc; | |
322 | ||
323 | return (pc >= lwp->step_range_start && pc < lwp->step_range_end); | |
324 | } | |
325 | ||
326 | struct pending_signals | |
327 | { | |
328 | int signal; | |
329 | siginfo_t info; | |
330 | struct pending_signals *prev; | |
331 | }; | |
332 | ||
333 | /* The read/write ends of the pipe registered as waitable file in the | |
334 | event loop. */ | |
335 | static int linux_event_pipe[2] = { -1, -1 }; | |
336 | ||
337 | /* True if we're currently in async mode. */ | |
338 | #define target_is_async_p() (linux_event_pipe[0] != -1) | |
339 | ||
340 | static void send_sigstop (struct lwp_info *lwp); | |
341 | static void wait_for_sigstop (void); | |
342 | ||
343 | /* Return non-zero if HEADER is a 64-bit ELF file. */ | |
344 | ||
345 | static int | |
346 | elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine) | |
347 | { | |
348 | if (header->e_ident[EI_MAG0] == ELFMAG0 | |
349 | && header->e_ident[EI_MAG1] == ELFMAG1 | |
350 | && header->e_ident[EI_MAG2] == ELFMAG2 | |
351 | && header->e_ident[EI_MAG3] == ELFMAG3) | |
352 | { | |
353 | *machine = header->e_machine; | |
354 | return header->e_ident[EI_CLASS] == ELFCLASS64; | |
355 | ||
356 | } | |
357 | *machine = EM_NONE; | |
358 | return -1; | |
359 | } | |
360 | ||
361 | /* Return non-zero if FILE is a 64-bit ELF file, | |
362 | zero if the file is not a 64-bit ELF file, | |
363 | and -1 if the file is not accessible or doesn't exist. */ | |
364 | ||
365 | static int | |
366 | elf_64_file_p (const char *file, unsigned int *machine) | |
367 | { | |
368 | Elf64_Ehdr header; | |
369 | int fd; | |
370 | ||
371 | fd = open (file, O_RDONLY); | |
372 | if (fd < 0) | |
373 | return -1; | |
374 | ||
375 | if (read (fd, &header, sizeof (header)) != sizeof (header)) | |
376 | { | |
377 | close (fd); | |
378 | return 0; | |
379 | } | |
380 | close (fd); | |
381 | ||
382 | return elf_64_header_p (&header, machine); | |
383 | } | |
384 | ||
385 | /* Accepts an integer PID; Returns true if the executable PID is | |
386 | running is a 64-bit ELF file.. */ | |
387 | ||
388 | int | |
389 | linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine) | |
390 | { | |
391 | char file[PATH_MAX]; | |
392 | ||
393 | sprintf (file, "/proc/%d/exe", pid); | |
394 | return elf_64_file_p (file, machine); | |
395 | } | |
396 | ||
397 | static void | |
398 | delete_lwp (struct lwp_info *lwp) | |
399 | { | |
400 | struct thread_info *thr = get_lwp_thread (lwp); | |
401 | ||
402 | if (debug_threads) | |
403 | debug_printf ("deleting %ld\n", lwpid_of (thr)); | |
404 | ||
405 | remove_thread (thr); | |
406 | free (lwp->arch_private); | |
407 | free (lwp); | |
408 | } | |
409 | ||
410 | /* Add a process to the common process list, and set its private | |
411 | data. */ | |
412 | ||
413 | static struct process_info * | |
414 | linux_add_process (int pid, int attached) | |
415 | { | |
416 | struct process_info *proc; | |
417 | ||
418 | proc = add_process (pid, attached); | |
419 | proc->priv = XCNEW (struct process_info_private); | |
420 | ||
421 | if (the_low_target.new_process != NULL) | |
422 | proc->priv->arch_private = the_low_target.new_process (); | |
423 | ||
424 | return proc; | |
425 | } | |
426 | ||
427 | static CORE_ADDR get_pc (struct lwp_info *lwp); | |
428 | ||
429 | /* Call the target arch_setup function on the current thread. */ | |
430 | ||
431 | static void | |
432 | linux_arch_setup (void) | |
433 | { | |
434 | the_low_target.arch_setup (); | |
435 | } | |
436 | ||
437 | /* Call the target arch_setup function on THREAD. */ | |
438 | ||
439 | static void | |
440 | linux_arch_setup_thread (struct thread_info *thread) | |
441 | { | |
442 | struct thread_info *saved_thread; | |
443 | ||
444 | saved_thread = current_thread; | |
445 | current_thread = thread; | |
446 | ||
447 | linux_arch_setup (); | |
448 | ||
449 | current_thread = saved_thread; | |
450 | } | |
451 | ||
452 | /* Handle a GNU/Linux extended wait response. If we see a clone, | |
453 | fork, or vfork event, we need to add the new LWP to our list | |
454 | (and return 0 so as not to report the trap to higher layers). | |
455 | If we see an exec event, we will modify ORIG_EVENT_LWP to point | |
456 | to a new LWP representing the new program. */ | |
457 | ||
458 | static int | |
459 | handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat) | |
460 | { | |
461 | struct lwp_info *event_lwp = *orig_event_lwp; | |
462 | int event = linux_ptrace_get_extended_event (wstat); | |
463 | struct thread_info *event_thr = get_lwp_thread (event_lwp); | |
464 | struct lwp_info *new_lwp; | |
465 | ||
466 | gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE); | |
467 | ||
468 | /* All extended events we currently use are mid-syscall. Only | |
469 | PTRACE_EVENT_STOP is delivered more like a signal-stop, but | |
470 | you have to be using PTRACE_SEIZE to get that. */ | |
471 | event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY; | |
472 | ||
473 | if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK) | |
474 | || (event == PTRACE_EVENT_CLONE)) | |
475 | { | |
476 | ptid_t ptid; | |
477 | unsigned long new_pid; | |
478 | int ret, status; | |
479 | ||
480 | /* Get the pid of the new lwp. */ | |
481 | ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0, | |
482 | &new_pid); | |
483 | ||
484 | /* If we haven't already seen the new PID stop, wait for it now. */ | |
485 | if (!pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
486 | { | |
487 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
488 | hits the SIGSTOP, but we're already attached. */ | |
489 | ||
490 | ret = my_waitpid (new_pid, &status, __WALL); | |
491 | ||
492 | if (ret == -1) | |
493 | perror_with_name ("waiting for new child"); | |
494 | else if (ret != new_pid) | |
495 | warning ("wait returned unexpected PID %d", ret); | |
496 | else if (!WIFSTOPPED (status)) | |
497 | warning ("wait returned unexpected status 0x%x", status); | |
498 | } | |
499 | ||
500 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) | |
501 | { | |
502 | struct process_info *parent_proc; | |
503 | struct process_info *child_proc; | |
504 | struct lwp_info *child_lwp; | |
505 | struct thread_info *child_thr; | |
506 | struct target_desc *tdesc; | |
507 | ||
508 | ptid = ptid_build (new_pid, new_pid, 0); | |
509 | ||
510 | if (debug_threads) | |
511 | { | |
512 | debug_printf ("HEW: Got fork event from LWP %ld, " | |
513 | "new child is %d\n", | |
514 | ptid_get_lwp (ptid_of (event_thr)), | |
515 | ptid_get_pid (ptid)); | |
516 | } | |
517 | ||
518 | /* Add the new process to the tables and clone the breakpoint | |
519 | lists of the parent. We need to do this even if the new process | |
520 | will be detached, since we will need the process object and the | |
521 | breakpoints to remove any breakpoints from memory when we | |
522 | detach, and the client side will access registers. */ | |
523 | child_proc = linux_add_process (new_pid, 0); | |
524 | gdb_assert (child_proc != NULL); | |
525 | child_lwp = add_lwp (ptid); | |
526 | gdb_assert (child_lwp != NULL); | |
527 | child_lwp->stopped = 1; | |
528 | child_lwp->must_set_ptrace_flags = 1; | |
529 | child_lwp->status_pending_p = 0; | |
530 | child_thr = get_lwp_thread (child_lwp); | |
531 | child_thr->last_resume_kind = resume_stop; | |
532 | child_thr->last_status.kind = TARGET_WAITKIND_STOPPED; | |
533 | ||
534 | /* If we're suspending all threads, leave this one suspended | |
535 | too. If the fork/clone parent is stepping over a breakpoint, | |
536 | all other threads have been suspended already. Leave the | |
537 | child suspended too. */ | |
538 | if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS | |
539 | || event_lwp->bp_reinsert != 0) | |
540 | { | |
541 | if (debug_threads) | |
542 | debug_printf ("HEW: leaving child suspended\n"); | |
543 | child_lwp->suspended = 1; | |
544 | } | |
545 | ||
546 | parent_proc = get_thread_process (event_thr); | |
547 | child_proc->attached = parent_proc->attached; | |
548 | ||
549 | if (event_lwp->bp_reinsert != 0 | |
550 | && can_software_single_step () | |
551 | && event == PTRACE_EVENT_VFORK) | |
552 | { | |
553 | /* If we leave reinsert breakpoints there, child will | |
554 | hit it, so uninsert reinsert breakpoints from parent | |
555 | (and child). Once vfork child is done, reinsert | |
556 | them back to parent. */ | |
557 | uninsert_reinsert_breakpoints (event_thr); | |
558 | } | |
559 | ||
560 | clone_all_breakpoints (child_thr, event_thr); | |
561 | ||
562 | tdesc = XNEW (struct target_desc); | |
563 | copy_target_description (tdesc, parent_proc->tdesc); | |
564 | child_proc->tdesc = tdesc; | |
565 | ||
566 | /* Clone arch-specific process data. */ | |
567 | if (the_low_target.new_fork != NULL) | |
568 | the_low_target.new_fork (parent_proc, child_proc); | |
569 | ||
570 | /* Save fork info in the parent thread. */ | |
571 | if (event == PTRACE_EVENT_FORK) | |
572 | event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED; | |
573 | else if (event == PTRACE_EVENT_VFORK) | |
574 | event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED; | |
575 | ||
576 | event_lwp->waitstatus.value.related_pid = ptid; | |
577 | ||
578 | /* The status_pending field contains bits denoting the | |
579 | extended event, so when the pending event is handled, | |
580 | the handler will look at lwp->waitstatus. */ | |
581 | event_lwp->status_pending_p = 1; | |
582 | event_lwp->status_pending = wstat; | |
583 | ||
584 | /* If the parent thread is doing step-over with reinsert | |
585 | breakpoints, the list of reinsert breakpoints are cloned | |
586 | from the parent's. Remove them from the child process. | |
587 | In case of vfork, we'll reinsert them back once vforked | |
588 | child is done. */ | |
589 | if (event_lwp->bp_reinsert != 0 | |
590 | && can_software_single_step ()) | |
591 | { | |
592 | /* The child process is forked and stopped, so it is safe | |
593 | to access its memory without stopping all other threads | |
594 | from other processes. */ | |
595 | delete_reinsert_breakpoints (child_thr); | |
596 | ||
597 | gdb_assert (has_reinsert_breakpoints (event_thr)); | |
598 | gdb_assert (!has_reinsert_breakpoints (child_thr)); | |
599 | } | |
600 | ||
601 | /* Report the event. */ | |
602 | return 0; | |
603 | } | |
604 | ||
605 | if (debug_threads) | |
606 | debug_printf ("HEW: Got clone event " | |
607 | "from LWP %ld, new child is LWP %ld\n", | |
608 | lwpid_of (event_thr), new_pid); | |
609 | ||
610 | ptid = ptid_build (pid_of (event_thr), new_pid, 0); | |
611 | new_lwp = add_lwp (ptid); | |
612 | ||
613 | /* Either we're going to immediately resume the new thread | |
614 | or leave it stopped. linux_resume_one_lwp is a nop if it | |
615 | thinks the thread is currently running, so set this first | |
616 | before calling linux_resume_one_lwp. */ | |
617 | new_lwp->stopped = 1; | |
618 | ||
619 | /* If we're suspending all threads, leave this one suspended | |
620 | too. If the fork/clone parent is stepping over a breakpoint, | |
621 | all other threads have been suspended already. Leave the | |
622 | child suspended too. */ | |
623 | if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS | |
624 | || event_lwp->bp_reinsert != 0) | |
625 | new_lwp->suspended = 1; | |
626 | ||
627 | /* Normally we will get the pending SIGSTOP. But in some cases | |
628 | we might get another signal delivered to the group first. | |
629 | If we do get another signal, be sure not to lose it. */ | |
630 | if (WSTOPSIG (status) != SIGSTOP) | |
631 | { | |
632 | new_lwp->stop_expected = 1; | |
633 | new_lwp->status_pending_p = 1; | |
634 | new_lwp->status_pending = status; | |
635 | } | |
636 | else if (report_thread_events) | |
637 | { | |
638 | new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED; | |
639 | new_lwp->status_pending_p = 1; | |
640 | new_lwp->status_pending = status; | |
641 | } | |
642 | ||
643 | /* Don't report the event. */ | |
644 | return 1; | |
645 | } | |
646 | else if (event == PTRACE_EVENT_VFORK_DONE) | |
647 | { | |
648 | event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
649 | ||
650 | if (event_lwp->bp_reinsert != 0 && can_software_single_step ()) | |
651 | { | |
652 | reinsert_reinsert_breakpoints (event_thr); | |
653 | ||
654 | gdb_assert (has_reinsert_breakpoints (event_thr)); | |
655 | } | |
656 | ||
657 | /* Report the event. */ | |
658 | return 0; | |
659 | } | |
660 | else if (event == PTRACE_EVENT_EXEC && report_exec_events) | |
661 | { | |
662 | struct process_info *proc; | |
663 | VEC (int) *syscalls_to_catch; | |
664 | ptid_t event_ptid; | |
665 | pid_t event_pid; | |
666 | ||
667 | if (debug_threads) | |
668 | { | |
669 | debug_printf ("HEW: Got exec event from LWP %ld\n", | |
670 | lwpid_of (event_thr)); | |
671 | } | |
672 | ||
673 | /* Get the event ptid. */ | |
674 | event_ptid = ptid_of (event_thr); | |
675 | event_pid = ptid_get_pid (event_ptid); | |
676 | ||
677 | /* Save the syscall list from the execing process. */ | |
678 | proc = get_thread_process (event_thr); | |
679 | syscalls_to_catch = proc->syscalls_to_catch; | |
680 | proc->syscalls_to_catch = NULL; | |
681 | ||
682 | /* Delete the execing process and all its threads. */ | |
683 | linux_mourn (proc); | |
684 | current_thread = NULL; | |
685 | ||
686 | /* Create a new process/lwp/thread. */ | |
687 | proc = linux_add_process (event_pid, 0); | |
688 | event_lwp = add_lwp (event_ptid); | |
689 | event_thr = get_lwp_thread (event_lwp); | |
690 | gdb_assert (current_thread == event_thr); | |
691 | linux_arch_setup_thread (event_thr); | |
692 | ||
693 | /* Set the event status. */ | |
694 | event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD; | |
695 | event_lwp->waitstatus.value.execd_pathname | |
696 | = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr))); | |
697 | ||
698 | /* Mark the exec status as pending. */ | |
699 | event_lwp->stopped = 1; | |
700 | event_lwp->status_pending_p = 1; | |
701 | event_lwp->status_pending = wstat; | |
702 | event_thr->last_resume_kind = resume_continue; | |
703 | event_thr->last_status.kind = TARGET_WAITKIND_IGNORE; | |
704 | ||
705 | /* Update syscall state in the new lwp, effectively mid-syscall too. */ | |
706 | event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY; | |
707 | ||
708 | /* Restore the list to catch. Don't rely on the client, which is free | |
709 | to avoid sending a new list when the architecture doesn't change. | |
710 | Also, for ANY_SYSCALL, the architecture doesn't really matter. */ | |
711 | proc->syscalls_to_catch = syscalls_to_catch; | |
712 | ||
713 | /* Report the event. */ | |
714 | *orig_event_lwp = event_lwp; | |
715 | return 0; | |
716 | } | |
717 | ||
718 | internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event); | |
719 | } | |
720 | ||
721 | /* Return the PC as read from the regcache of LWP, without any | |
722 | adjustment. */ | |
723 | ||
724 | static CORE_ADDR | |
725 | get_pc (struct lwp_info *lwp) | |
726 | { | |
727 | struct thread_info *saved_thread; | |
728 | struct regcache *regcache; | |
729 | CORE_ADDR pc; | |
730 | ||
731 | if (the_low_target.get_pc == NULL) | |
732 | return 0; | |
733 | ||
734 | saved_thread = current_thread; | |
735 | current_thread = get_lwp_thread (lwp); | |
736 | ||
737 | regcache = get_thread_regcache (current_thread, 1); | |
738 | pc = (*the_low_target.get_pc) (regcache); | |
739 | ||
740 | if (debug_threads) | |
741 | debug_printf ("pc is 0x%lx\n", (long) pc); | |
742 | ||
743 | current_thread = saved_thread; | |
744 | return pc; | |
745 | } | |
746 | ||
747 | /* This function should only be called if LWP got a SYSCALL_SIGTRAP. | |
748 | Fill *SYSNO with the syscall nr trapped. */ | |
749 | ||
750 | static void | |
751 | get_syscall_trapinfo (struct lwp_info *lwp, int *sysno) | |
752 | { | |
753 | struct thread_info *saved_thread; | |
754 | struct regcache *regcache; | |
755 | ||
756 | if (the_low_target.get_syscall_trapinfo == NULL) | |
757 | { | |
758 | /* If we cannot get the syscall trapinfo, report an unknown | |
759 | system call number. */ | |
760 | *sysno = UNKNOWN_SYSCALL; | |
761 | return; | |
762 | } | |
763 | ||
764 | saved_thread = current_thread; | |
765 | current_thread = get_lwp_thread (lwp); | |
766 | ||
767 | regcache = get_thread_regcache (current_thread, 1); | |
768 | (*the_low_target.get_syscall_trapinfo) (regcache, sysno); | |
769 | ||
770 | if (debug_threads) | |
771 | debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno); | |
772 | ||
773 | current_thread = saved_thread; | |
774 | } | |
775 | ||
776 | static int check_stopped_by_watchpoint (struct lwp_info *child); | |
777 | ||
778 | /* Called when the LWP stopped for a signal/trap. If it stopped for a | |
779 | trap check what caused it (breakpoint, watchpoint, trace, etc.), | |
780 | and save the result in the LWP's stop_reason field. If it stopped | |
781 | for a breakpoint, decrement the PC if necessary on the lwp's | |
782 | architecture. Returns true if we now have the LWP's stop PC. */ | |
783 | ||
784 | static int | |
785 | save_stop_reason (struct lwp_info *lwp) | |
786 | { | |
787 | CORE_ADDR pc; | |
788 | CORE_ADDR sw_breakpoint_pc; | |
789 | struct thread_info *saved_thread; | |
790 | #if USE_SIGTRAP_SIGINFO | |
791 | siginfo_t siginfo; | |
792 | #endif | |
793 | ||
794 | if (the_low_target.get_pc == NULL) | |
795 | return 0; | |
796 | ||
797 | pc = get_pc (lwp); | |
798 | sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break; | |
799 | ||
800 | /* breakpoint_at reads from the current thread. */ | |
801 | saved_thread = current_thread; | |
802 | current_thread = get_lwp_thread (lwp); | |
803 | ||
804 | #if USE_SIGTRAP_SIGINFO | |
805 | if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread), | |
806 | (PTRACE_TYPE_ARG3) 0, &siginfo) == 0) | |
807 | { | |
808 | if (siginfo.si_signo == SIGTRAP) | |
809 | { | |
810 | if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code) | |
811 | && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) | |
812 | { | |
813 | /* The si_code is ambiguous on this arch -- check debug | |
814 | registers. */ | |
815 | if (!check_stopped_by_watchpoint (lwp)) | |
816 | lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
817 | } | |
818 | else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)) | |
819 | { | |
820 | /* If we determine the LWP stopped for a SW breakpoint, | |
821 | trust it. Particularly don't check watchpoint | |
822 | registers, because at least on s390, we'd find | |
823 | stopped-by-watchpoint as long as there's a watchpoint | |
824 | set. */ | |
825 | lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
826 | } | |
827 | else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) | |
828 | { | |
829 | /* This can indicate either a hardware breakpoint or | |
830 | hardware watchpoint. Check debug registers. */ | |
831 | if (!check_stopped_by_watchpoint (lwp)) | |
832 | lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
833 | } | |
834 | else if (siginfo.si_code == TRAP_TRACE) | |
835 | { | |
836 | /* We may have single stepped an instruction that | |
837 | triggered a watchpoint. In that case, on some | |
838 | architectures (such as x86), instead of TRAP_HWBKPT, | |
839 | si_code indicates TRAP_TRACE, and we need to check | |
840 | the debug registers separately. */ | |
841 | if (!check_stopped_by_watchpoint (lwp)) | |
842 | lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP; | |
843 | } | |
844 | } | |
845 | } | |
846 | #else | |
847 | /* We may have just stepped a breakpoint instruction. E.g., in | |
848 | non-stop mode, GDB first tells the thread A to step a range, and | |
849 | then the user inserts a breakpoint inside the range. In that | |
850 | case we need to report the breakpoint PC. */ | |
851 | if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc) | |
852 | && (*the_low_target.breakpoint_at) (sw_breakpoint_pc)) | |
853 | lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
854 | ||
855 | if (hardware_breakpoint_inserted_here (pc)) | |
856 | lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
857 | ||
858 | if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON) | |
859 | check_stopped_by_watchpoint (lwp); | |
860 | #endif | |
861 | ||
862 | if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT) | |
863 | { | |
864 | if (debug_threads) | |
865 | { | |
866 | struct thread_info *thr = get_lwp_thread (lwp); | |
867 | ||
868 | debug_printf ("CSBB: %s stopped by software breakpoint\n", | |
869 | target_pid_to_str (ptid_of (thr))); | |
870 | } | |
871 | ||
872 | /* Back up the PC if necessary. */ | |
873 | if (pc != sw_breakpoint_pc) | |
874 | { | |
875 | struct regcache *regcache | |
876 | = get_thread_regcache (current_thread, 1); | |
877 | (*the_low_target.set_pc) (regcache, sw_breakpoint_pc); | |
878 | } | |
879 | ||
880 | /* Update this so we record the correct stop PC below. */ | |
881 | pc = sw_breakpoint_pc; | |
882 | } | |
883 | else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
884 | { | |
885 | if (debug_threads) | |
886 | { | |
887 | struct thread_info *thr = get_lwp_thread (lwp); | |
888 | ||
889 | debug_printf ("CSBB: %s stopped by hardware breakpoint\n", | |
890 | target_pid_to_str (ptid_of (thr))); | |
891 | } | |
892 | } | |
893 | else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT) | |
894 | { | |
895 | if (debug_threads) | |
896 | { | |
897 | struct thread_info *thr = get_lwp_thread (lwp); | |
898 | ||
899 | debug_printf ("CSBB: %s stopped by hardware watchpoint\n", | |
900 | target_pid_to_str (ptid_of (thr))); | |
901 | } | |
902 | } | |
903 | else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP) | |
904 | { | |
905 | if (debug_threads) | |
906 | { | |
907 | struct thread_info *thr = get_lwp_thread (lwp); | |
908 | ||
909 | debug_printf ("CSBB: %s stopped by trace\n", | |
910 | target_pid_to_str (ptid_of (thr))); | |
911 | } | |
912 | } | |
913 | ||
914 | lwp->stop_pc = pc; | |
915 | current_thread = saved_thread; | |
916 | return 1; | |
917 | } | |
918 | ||
919 | static struct lwp_info * | |
920 | add_lwp (ptid_t ptid) | |
921 | { | |
922 | struct lwp_info *lwp; | |
923 | ||
924 | lwp = XCNEW (struct lwp_info); | |
925 | ||
926 | lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
927 | ||
928 | if (the_low_target.new_thread != NULL) | |
929 | the_low_target.new_thread (lwp); | |
930 | ||
931 | lwp->thread = add_thread (ptid, lwp); | |
932 | ||
933 | return lwp; | |
934 | } | |
935 | ||
936 | /* Start an inferior process and returns its pid. | |
937 | ALLARGS is a vector of program-name and args. */ | |
938 | ||
939 | static int | |
940 | linux_create_inferior (char *program, char **allargs) | |
941 | { | |
942 | struct lwp_info *new_lwp; | |
943 | int pid; | |
944 | ptid_t ptid; | |
945 | struct cleanup *restore_personality | |
946 | = maybe_disable_address_space_randomization (disable_randomization); | |
947 | ||
948 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) | |
949 | pid = vfork (); | |
950 | #else | |
951 | pid = fork (); | |
952 | #endif | |
953 | if (pid < 0) | |
954 | perror_with_name ("fork"); | |
955 | ||
956 | if (pid == 0) | |
957 | { | |
958 | close_most_fds (); | |
959 | ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0); | |
960 | ||
961 | setpgid (0, 0); | |
962 | ||
963 | /* If gdbserver is connected to gdb via stdio, redirect the inferior's | |
964 | stdout to stderr so that inferior i/o doesn't corrupt the connection. | |
965 | Also, redirect stdin to /dev/null. */ | |
966 | if (remote_connection_is_stdio ()) | |
967 | { | |
968 | close (0); | |
969 | open ("/dev/null", O_RDONLY); | |
970 | dup2 (2, 1); | |
971 | if (write (2, "stdin/stdout redirected\n", | |
972 | sizeof ("stdin/stdout redirected\n") - 1) < 0) | |
973 | { | |
974 | /* Errors ignored. */; | |
975 | } | |
976 | } | |
977 | ||
978 | execv (program, allargs); | |
979 | if (errno == ENOENT) | |
980 | execvp (program, allargs); | |
981 | ||
982 | fprintf (stderr, "Cannot exec %s: %s.\n", program, | |
983 | strerror (errno)); | |
984 | fflush (stderr); | |
985 | _exit (0177); | |
986 | } | |
987 | ||
988 | do_cleanups (restore_personality); | |
989 | ||
990 | linux_add_process (pid, 0); | |
991 | ||
992 | ptid = ptid_build (pid, pid, 0); | |
993 | new_lwp = add_lwp (ptid); | |
994 | new_lwp->must_set_ptrace_flags = 1; | |
995 | ||
996 | return pid; | |
997 | } | |
998 | ||
999 | /* Implement the post_create_inferior target_ops method. */ | |
1000 | ||
1001 | static void | |
1002 | linux_post_create_inferior (void) | |
1003 | { | |
1004 | struct lwp_info *lwp = get_thread_lwp (current_thread); | |
1005 | ||
1006 | linux_arch_setup (); | |
1007 | ||
1008 | if (lwp->must_set_ptrace_flags) | |
1009 | { | |
1010 | struct process_info *proc = current_process (); | |
1011 | int options = linux_low_ptrace_options (proc->attached); | |
1012 | ||
1013 | linux_enable_event_reporting (lwpid_of (current_thread), options); | |
1014 | lwp->must_set_ptrace_flags = 0; | |
1015 | } | |
1016 | } | |
1017 | ||
1018 | /* Attach to an inferior process. Returns 0 on success, ERRNO on | |
1019 | error. */ | |
1020 | ||
1021 | int | |
1022 | linux_attach_lwp (ptid_t ptid) | |
1023 | { | |
1024 | struct lwp_info *new_lwp; | |
1025 | int lwpid = ptid_get_lwp (ptid); | |
1026 | ||
1027 | if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0) | |
1028 | != 0) | |
1029 | return errno; | |
1030 | ||
1031 | new_lwp = add_lwp (ptid); | |
1032 | ||
1033 | /* We need to wait for SIGSTOP before being able to make the next | |
1034 | ptrace call on this LWP. */ | |
1035 | new_lwp->must_set_ptrace_flags = 1; | |
1036 | ||
1037 | if (linux_proc_pid_is_stopped (lwpid)) | |
1038 | { | |
1039 | if (debug_threads) | |
1040 | debug_printf ("Attached to a stopped process\n"); | |
1041 | ||
1042 | /* The process is definitely stopped. It is in a job control | |
1043 | stop, unless the kernel predates the TASK_STOPPED / | |
1044 | TASK_TRACED distinction, in which case it might be in a | |
1045 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1046 | can kill it, signal it, et cetera. | |
1047 | ||
1048 | First make sure there is a pending SIGSTOP. Since we are | |
1049 | already attached, the process can not transition from stopped | |
1050 | to running without a PTRACE_CONT; so we know this signal will | |
1051 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1052 | probably already in the queue (unless this kernel is old | |
1053 | enough to use TASK_STOPPED for ptrace stops); but since | |
1054 | SIGSTOP is not an RT signal, it can only be queued once. */ | |
1055 | kill_lwp (lwpid, SIGSTOP); | |
1056 | ||
1057 | /* Finally, resume the stopped process. This will deliver the | |
1058 | SIGSTOP (or a higher priority signal, just like normal | |
1059 | PTRACE_ATTACH), which we'll catch later on. */ | |
1060 | ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0); | |
1061 | } | |
1062 | ||
1063 | /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH | |
1064 | brings it to a halt. | |
1065 | ||
1066 | There are several cases to consider here: | |
1067 | ||
1068 | 1) gdbserver has already attached to the process and is being notified | |
1069 | of a new thread that is being created. | |
1070 | In this case we should ignore that SIGSTOP and resume the | |
1071 | process. This is handled below by setting stop_expected = 1, | |
1072 | and the fact that add_thread sets last_resume_kind == | |
1073 | resume_continue. | |
1074 | ||
1075 | 2) This is the first thread (the process thread), and we're attaching | |
1076 | to it via attach_inferior. | |
1077 | In this case we want the process thread to stop. | |
1078 | This is handled by having linux_attach set last_resume_kind == | |
1079 | resume_stop after we return. | |
1080 | ||
1081 | If the pid we are attaching to is also the tgid, we attach to and | |
1082 | stop all the existing threads. Otherwise, we attach to pid and | |
1083 | ignore any other threads in the same group as this pid. | |
1084 | ||
1085 | 3) GDB is connecting to gdbserver and is requesting an enumeration of all | |
1086 | existing threads. | |
1087 | In this case we want the thread to stop. | |
1088 | FIXME: This case is currently not properly handled. | |
1089 | We should wait for the SIGSTOP but don't. Things work apparently | |
1090 | because enough time passes between when we ptrace (ATTACH) and when | |
1091 | gdb makes the next ptrace call on the thread. | |
1092 | ||
1093 | On the other hand, if we are currently trying to stop all threads, we | |
1094 | should treat the new thread as if we had sent it a SIGSTOP. This works | |
1095 | because we are guaranteed that the add_lwp call above added us to the | |
1096 | end of the list, and so the new thread has not yet reached | |
1097 | wait_for_sigstop (but will). */ | |
1098 | new_lwp->stop_expected = 1; | |
1099 | ||
1100 | return 0; | |
1101 | } | |
1102 | ||
1103 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not | |
1104 | already attached. Returns true if a new LWP is found, false | |
1105 | otherwise. */ | |
1106 | ||
1107 | static int | |
1108 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1109 | { | |
1110 | /* Is this a new thread? */ | |
1111 | if (find_thread_ptid (ptid) == NULL) | |
1112 | { | |
1113 | int lwpid = ptid_get_lwp (ptid); | |
1114 | int err; | |
1115 | ||
1116 | if (debug_threads) | |
1117 | debug_printf ("Found new lwp %d\n", lwpid); | |
1118 | ||
1119 | err = linux_attach_lwp (ptid); | |
1120 | ||
1121 | /* Be quiet if we simply raced with the thread exiting. EPERM | |
1122 | is returned if the thread's task still exists, and is marked | |
1123 | as exited or zombie, as well as other conditions, so in that | |
1124 | case, confirm the status in /proc/PID/status. */ | |
1125 | if (err == ESRCH | |
1126 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1127 | { | |
1128 | if (debug_threads) | |
1129 | { | |
1130 | debug_printf ("Cannot attach to lwp %d: " | |
1131 | "thread is gone (%d: %s)\n", | |
1132 | lwpid, err, strerror (err)); | |
1133 | } | |
1134 | } | |
1135 | else if (err != 0) | |
1136 | { | |
1137 | warning (_("Cannot attach to lwp %d: %s"), | |
1138 | lwpid, | |
1139 | linux_ptrace_attach_fail_reason_string (ptid, err)); | |
1140 | } | |
1141 | ||
1142 | return 1; | |
1143 | } | |
1144 | return 0; | |
1145 | } | |
1146 | ||
1147 | static void async_file_mark (void); | |
1148 | ||
1149 | /* Attach to PID. If PID is the tgid, attach to it and all | |
1150 | of its threads. */ | |
1151 | ||
1152 | static int | |
1153 | linux_attach (unsigned long pid) | |
1154 | { | |
1155 | struct process_info *proc; | |
1156 | struct thread_info *initial_thread; | |
1157 | ptid_t ptid = ptid_build (pid, pid, 0); | |
1158 | int err; | |
1159 | ||
1160 | /* Attach to PID. We will check for other threads | |
1161 | soon. */ | |
1162 | err = linux_attach_lwp (ptid); | |
1163 | if (err != 0) | |
1164 | error ("Cannot attach to process %ld: %s", | |
1165 | pid, linux_ptrace_attach_fail_reason_string (ptid, err)); | |
1166 | ||
1167 | proc = linux_add_process (pid, 1); | |
1168 | ||
1169 | /* Don't ignore the initial SIGSTOP if we just attached to this | |
1170 | process. It will be collected by wait shortly. */ | |
1171 | initial_thread = find_thread_ptid (ptid_build (pid, pid, 0)); | |
1172 | initial_thread->last_resume_kind = resume_stop; | |
1173 | ||
1174 | /* We must attach to every LWP. If /proc is mounted, use that to | |
1175 | find them now. On the one hand, the inferior may be using raw | |
1176 | clone instead of using pthreads. On the other hand, even if it | |
1177 | is using pthreads, GDB may not be connected yet (thread_db needs | |
1178 | to do symbol lookups, through qSymbol). Also, thread_db walks | |
1179 | structures in the inferior's address space to find the list of | |
1180 | threads/LWPs, and those structures may well be corrupted. Note | |
1181 | that once thread_db is loaded, we'll still use it to list threads | |
1182 | and associate pthread info with each LWP. */ | |
1183 | linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback); | |
1184 | ||
1185 | /* GDB will shortly read the xml target description for this | |
1186 | process, to figure out the process' architecture. But the target | |
1187 | description is only filled in when the first process/thread in | |
1188 | the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do | |
1189 | that now, otherwise, if GDB is fast enough, it could read the | |
1190 | target description _before_ that initial stop. */ | |
1191 | if (non_stop) | |
1192 | { | |
1193 | struct lwp_info *lwp; | |
1194 | int wstat, lwpid; | |
1195 | ptid_t pid_ptid = pid_to_ptid (pid); | |
1196 | ||
1197 | lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid, | |
1198 | &wstat, __WALL); | |
1199 | gdb_assert (lwpid > 0); | |
1200 | ||
1201 | lwp = find_lwp_pid (pid_to_ptid (lwpid)); | |
1202 | ||
1203 | if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP) | |
1204 | { | |
1205 | lwp->status_pending_p = 1; | |
1206 | lwp->status_pending = wstat; | |
1207 | } | |
1208 | ||
1209 | initial_thread->last_resume_kind = resume_continue; | |
1210 | ||
1211 | async_file_mark (); | |
1212 | ||
1213 | gdb_assert (proc->tdesc != NULL); | |
1214 | } | |
1215 | ||
1216 | return 0; | |
1217 | } | |
1218 | ||
1219 | struct counter | |
1220 | { | |
1221 | int pid; | |
1222 | int count; | |
1223 | }; | |
1224 | ||
1225 | static int | |
1226 | second_thread_of_pid_p (struct inferior_list_entry *entry, void *args) | |
1227 | { | |
1228 | struct counter *counter = (struct counter *) args; | |
1229 | ||
1230 | if (ptid_get_pid (entry->id) == counter->pid) | |
1231 | { | |
1232 | if (++counter->count > 1) | |
1233 | return 1; | |
1234 | } | |
1235 | ||
1236 | return 0; | |
1237 | } | |
1238 | ||
1239 | static int | |
1240 | last_thread_of_process_p (int pid) | |
1241 | { | |
1242 | struct counter counter = { pid , 0 }; | |
1243 | ||
1244 | return (find_inferior (&all_threads, | |
1245 | second_thread_of_pid_p, &counter) == NULL); | |
1246 | } | |
1247 | ||
1248 | /* Kill LWP. */ | |
1249 | ||
1250 | static void | |
1251 | linux_kill_one_lwp (struct lwp_info *lwp) | |
1252 | { | |
1253 | struct thread_info *thr = get_lwp_thread (lwp); | |
1254 | int pid = lwpid_of (thr); | |
1255 | ||
1256 | /* PTRACE_KILL is unreliable. After stepping into a signal handler, | |
1257 | there is no signal context, and ptrace(PTRACE_KILL) (or | |
1258 | ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like | |
1259 | ptrace(CONT, pid, 0,0) and just resumes the tracee. A better | |
1260 | alternative is to kill with SIGKILL. We only need one SIGKILL | |
1261 | per process, not one for each thread. But since we still support | |
1262 | support debugging programs using raw clone without CLONE_THREAD, | |
1263 | we send one for each thread. For years, we used PTRACE_KILL | |
1264 | only, so we're being a bit paranoid about some old kernels where | |
1265 | PTRACE_KILL might work better (dubious if there are any such, but | |
1266 | that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL | |
1267 | second, and so we're fine everywhere. */ | |
1268 | ||
1269 | errno = 0; | |
1270 | kill_lwp (pid, SIGKILL); | |
1271 | if (debug_threads) | |
1272 | { | |
1273 | int save_errno = errno; | |
1274 | ||
1275 | debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n", | |
1276 | target_pid_to_str (ptid_of (thr)), | |
1277 | save_errno ? strerror (save_errno) : "OK"); | |
1278 | } | |
1279 | ||
1280 | errno = 0; | |
1281 | ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0); | |
1282 | if (debug_threads) | |
1283 | { | |
1284 | int save_errno = errno; | |
1285 | ||
1286 | debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n", | |
1287 | target_pid_to_str (ptid_of (thr)), | |
1288 | save_errno ? strerror (save_errno) : "OK"); | |
1289 | } | |
1290 | } | |
1291 | ||
1292 | /* Kill LWP and wait for it to die. */ | |
1293 | ||
1294 | static void | |
1295 | kill_wait_lwp (struct lwp_info *lwp) | |
1296 | { | |
1297 | struct thread_info *thr = get_lwp_thread (lwp); | |
1298 | int pid = ptid_get_pid (ptid_of (thr)); | |
1299 | int lwpid = ptid_get_lwp (ptid_of (thr)); | |
1300 | int wstat; | |
1301 | int res; | |
1302 | ||
1303 | if (debug_threads) | |
1304 | debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid); | |
1305 | ||
1306 | do | |
1307 | { | |
1308 | linux_kill_one_lwp (lwp); | |
1309 | ||
1310 | /* Make sure it died. Notes: | |
1311 | ||
1312 | - The loop is most likely unnecessary. | |
1313 | ||
1314 | - We don't use linux_wait_for_event as that could delete lwps | |
1315 | while we're iterating over them. We're not interested in | |
1316 | any pending status at this point, only in making sure all | |
1317 | wait status on the kernel side are collected until the | |
1318 | process is reaped. | |
1319 | ||
1320 | - We don't use __WALL here as the __WALL emulation relies on | |
1321 | SIGCHLD, and killing a stopped process doesn't generate | |
1322 | one, nor an exit status. | |
1323 | */ | |
1324 | res = my_waitpid (lwpid, &wstat, 0); | |
1325 | if (res == -1 && errno == ECHILD) | |
1326 | res = my_waitpid (lwpid, &wstat, __WCLONE); | |
1327 | } while (res > 0 && WIFSTOPPED (wstat)); | |
1328 | ||
1329 | /* Even if it was stopped, the child may have already disappeared. | |
1330 | E.g., if it was killed by SIGKILL. */ | |
1331 | if (res < 0 && errno != ECHILD) | |
1332 | perror_with_name ("kill_wait_lwp"); | |
1333 | } | |
1334 | ||
1335 | /* Callback for `find_inferior'. Kills an lwp of a given process, | |
1336 | except the leader. */ | |
1337 | ||
1338 | static int | |
1339 | kill_one_lwp_callback (struct inferior_list_entry *entry, void *args) | |
1340 | { | |
1341 | struct thread_info *thread = (struct thread_info *) entry; | |
1342 | struct lwp_info *lwp = get_thread_lwp (thread); | |
1343 | int pid = * (int *) args; | |
1344 | ||
1345 | if (ptid_get_pid (entry->id) != pid) | |
1346 | return 0; | |
1347 | ||
1348 | /* We avoid killing the first thread here, because of a Linux kernel (at | |
1349 | least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before | |
1350 | the children get a chance to be reaped, it will remain a zombie | |
1351 | forever. */ | |
1352 | ||
1353 | if (lwpid_of (thread) == pid) | |
1354 | { | |
1355 | if (debug_threads) | |
1356 | debug_printf ("lkop: is last of process %s\n", | |
1357 | target_pid_to_str (entry->id)); | |
1358 | return 0; | |
1359 | } | |
1360 | ||
1361 | kill_wait_lwp (lwp); | |
1362 | return 0; | |
1363 | } | |
1364 | ||
1365 | static int | |
1366 | linux_kill (int pid) | |
1367 | { | |
1368 | struct process_info *process; | |
1369 | struct lwp_info *lwp; | |
1370 | ||
1371 | process = find_process_pid (pid); | |
1372 | if (process == NULL) | |
1373 | return -1; | |
1374 | ||
1375 | /* If we're killing a running inferior, make sure it is stopped | |
1376 | first, as PTRACE_KILL will not work otherwise. */ | |
1377 | stop_all_lwps (0, NULL); | |
1378 | ||
1379 | find_inferior (&all_threads, kill_one_lwp_callback , &pid); | |
1380 | ||
1381 | /* See the comment in linux_kill_one_lwp. We did not kill the first | |
1382 | thread in the list, so do so now. */ | |
1383 | lwp = find_lwp_pid (pid_to_ptid (pid)); | |
1384 | ||
1385 | if (lwp == NULL) | |
1386 | { | |
1387 | if (debug_threads) | |
1388 | debug_printf ("lk_1: cannot find lwp for pid: %d\n", | |
1389 | pid); | |
1390 | } | |
1391 | else | |
1392 | kill_wait_lwp (lwp); | |
1393 | ||
1394 | the_target->mourn (process); | |
1395 | ||
1396 | /* Since we presently can only stop all lwps of all processes, we | |
1397 | need to unstop lwps of other processes. */ | |
1398 | unstop_all_lwps (0, NULL); | |
1399 | return 0; | |
1400 | } | |
1401 | ||
1402 | /* Get pending signal of THREAD, for detaching purposes. This is the | |
1403 | signal the thread last stopped for, which we need to deliver to the | |
1404 | thread when detaching, otherwise, it'd be suppressed/lost. */ | |
1405 | ||
1406 | static int | |
1407 | get_detach_signal (struct thread_info *thread) | |
1408 | { | |
1409 | enum gdb_signal signo = GDB_SIGNAL_0; | |
1410 | int status; | |
1411 | struct lwp_info *lp = get_thread_lwp (thread); | |
1412 | ||
1413 | if (lp->status_pending_p) | |
1414 | status = lp->status_pending; | |
1415 | else | |
1416 | { | |
1417 | /* If the thread had been suspended by gdbserver, and it stopped | |
1418 | cleanly, then it'll have stopped with SIGSTOP. But we don't | |
1419 | want to deliver that SIGSTOP. */ | |
1420 | if (thread->last_status.kind != TARGET_WAITKIND_STOPPED | |
1421 | || thread->last_status.value.sig == GDB_SIGNAL_0) | |
1422 | return 0; | |
1423 | ||
1424 | /* Otherwise, we may need to deliver the signal we | |
1425 | intercepted. */ | |
1426 | status = lp->last_status; | |
1427 | } | |
1428 | ||
1429 | if (!WIFSTOPPED (status)) | |
1430 | { | |
1431 | if (debug_threads) | |
1432 | debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n", | |
1433 | target_pid_to_str (ptid_of (thread))); | |
1434 | return 0; | |
1435 | } | |
1436 | ||
1437 | /* Extended wait statuses aren't real SIGTRAPs. */ | |
1438 | if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status)) | |
1439 | { | |
1440 | if (debug_threads) | |
1441 | debug_printf ("GPS: lwp %s had stopped with extended " | |
1442 | "status: no pending signal\n", | |
1443 | target_pid_to_str (ptid_of (thread))); | |
1444 | return 0; | |
1445 | } | |
1446 | ||
1447 | signo = gdb_signal_from_host (WSTOPSIG (status)); | |
1448 | ||
1449 | if (program_signals_p && !program_signals[signo]) | |
1450 | { | |
1451 | if (debug_threads) | |
1452 | debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n", | |
1453 | target_pid_to_str (ptid_of (thread)), | |
1454 | gdb_signal_to_string (signo)); | |
1455 | return 0; | |
1456 | } | |
1457 | else if (!program_signals_p | |
1458 | /* If we have no way to know which signals GDB does not | |
1459 | want to have passed to the program, assume | |
1460 | SIGTRAP/SIGINT, which is GDB's default. */ | |
1461 | && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT)) | |
1462 | { | |
1463 | if (debug_threads) | |
1464 | debug_printf ("GPS: lwp %s had signal %s, " | |
1465 | "but we don't know if we should pass it. " | |
1466 | "Default to not.\n", | |
1467 | target_pid_to_str (ptid_of (thread)), | |
1468 | gdb_signal_to_string (signo)); | |
1469 | return 0; | |
1470 | } | |
1471 | else | |
1472 | { | |
1473 | if (debug_threads) | |
1474 | debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n", | |
1475 | target_pid_to_str (ptid_of (thread)), | |
1476 | gdb_signal_to_string (signo)); | |
1477 | ||
1478 | return WSTOPSIG (status); | |
1479 | } | |
1480 | } | |
1481 | ||
1482 | /* Detach from LWP. */ | |
1483 | ||
1484 | static void | |
1485 | linux_detach_one_lwp (struct lwp_info *lwp) | |
1486 | { | |
1487 | struct thread_info *thread = get_lwp_thread (lwp); | |
1488 | int sig; | |
1489 | int lwpid; | |
1490 | ||
1491 | /* If there is a pending SIGSTOP, get rid of it. */ | |
1492 | if (lwp->stop_expected) | |
1493 | { | |
1494 | if (debug_threads) | |
1495 | debug_printf ("Sending SIGCONT to %s\n", | |
1496 | target_pid_to_str (ptid_of (thread))); | |
1497 | ||
1498 | kill_lwp (lwpid_of (thread), SIGCONT); | |
1499 | lwp->stop_expected = 0; | |
1500 | } | |
1501 | ||
1502 | /* Pass on any pending signal for this thread. */ | |
1503 | sig = get_detach_signal (thread); | |
1504 | ||
1505 | /* Preparing to resume may try to write registers, and fail if the | |
1506 | lwp is zombie. If that happens, ignore the error. We'll handle | |
1507 | it below, when detach fails with ESRCH. */ | |
1508 | TRY | |
1509 | { | |
1510 | /* Flush any pending changes to the process's registers. */ | |
1511 | regcache_invalidate_thread (thread); | |
1512 | ||
1513 | /* Finally, let it resume. */ | |
1514 | if (the_low_target.prepare_to_resume != NULL) | |
1515 | the_low_target.prepare_to_resume (lwp); | |
1516 | } | |
1517 | CATCH (ex, RETURN_MASK_ERROR) | |
1518 | { | |
1519 | if (!check_ptrace_stopped_lwp_gone (lwp)) | |
1520 | throw_exception (ex); | |
1521 | } | |
1522 | END_CATCH | |
1523 | ||
1524 | lwpid = lwpid_of (thread); | |
1525 | if (ptrace (PTRACE_DETACH, lwpid, (PTRACE_TYPE_ARG3) 0, | |
1526 | (PTRACE_TYPE_ARG4) (long) sig) < 0) | |
1527 | { | |
1528 | int save_errno = errno; | |
1529 | ||
1530 | /* We know the thread exists, so ESRCH must mean the lwp is | |
1531 | zombie. This can happen if one of the already-detached | |
1532 | threads exits the whole thread group. In that case we're | |
1533 | still attached, and must reap the lwp. */ | |
1534 | if (save_errno == ESRCH) | |
1535 | { | |
1536 | int ret, status; | |
1537 | ||
1538 | ret = my_waitpid (lwpid, &status, __WALL); | |
1539 | if (ret == -1) | |
1540 | { | |
1541 | warning (_("Couldn't reap LWP %d while detaching: %s"), | |
1542 | lwpid, strerror (errno)); | |
1543 | } | |
1544 | else if (!WIFEXITED (status) && !WIFSIGNALED (status)) | |
1545 | { | |
1546 | warning (_("Reaping LWP %d while detaching " | |
1547 | "returned unexpected status 0x%x"), | |
1548 | lwpid, status); | |
1549 | } | |
1550 | } | |
1551 | else | |
1552 | { | |
1553 | error (_("Can't detach %s: %s"), | |
1554 | target_pid_to_str (ptid_of (thread)), | |
1555 | strerror (save_errno)); | |
1556 | } | |
1557 | } | |
1558 | else if (debug_threads) | |
1559 | { | |
1560 | debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
1561 | target_pid_to_str (ptid_of (thread)), | |
1562 | strsignal (sig)); | |
1563 | } | |
1564 | ||
1565 | delete_lwp (lwp); | |
1566 | } | |
1567 | ||
1568 | /* Callback for find_inferior. Detaches from non-leader threads of a | |
1569 | given process. */ | |
1570 | ||
1571 | static int | |
1572 | linux_detach_lwp_callback (struct inferior_list_entry *entry, void *args) | |
1573 | { | |
1574 | struct thread_info *thread = (struct thread_info *) entry; | |
1575 | struct lwp_info *lwp = get_thread_lwp (thread); | |
1576 | int pid = *(int *) args; | |
1577 | int lwpid = lwpid_of (thread); | |
1578 | ||
1579 | /* Skip other processes. */ | |
1580 | if (ptid_get_pid (entry->id) != pid) | |
1581 | return 0; | |
1582 | ||
1583 | /* We don't actually detach from the thread group leader just yet. | |
1584 | If the thread group exits, we must reap the zombie clone lwps | |
1585 | before we're able to reap the leader. */ | |
1586 | if (ptid_get_pid (entry->id) == lwpid) | |
1587 | return 0; | |
1588 | ||
1589 | linux_detach_one_lwp (lwp); | |
1590 | return 0; | |
1591 | } | |
1592 | ||
1593 | static int | |
1594 | linux_detach (int pid) | |
1595 | { | |
1596 | struct process_info *process; | |
1597 | struct lwp_info *main_lwp; | |
1598 | ||
1599 | process = find_process_pid (pid); | |
1600 | if (process == NULL) | |
1601 | return -1; | |
1602 | ||
1603 | /* As there's a step over already in progress, let it finish first, | |
1604 | otherwise nesting a stabilize_threads operation on top gets real | |
1605 | messy. */ | |
1606 | complete_ongoing_step_over (); | |
1607 | ||
1608 | /* Stop all threads before detaching. First, ptrace requires that | |
1609 | the thread is stopped to sucessfully detach. Second, thread_db | |
1610 | may need to uninstall thread event breakpoints from memory, which | |
1611 | only works with a stopped process anyway. */ | |
1612 | stop_all_lwps (0, NULL); | |
1613 | ||
1614 | #ifdef USE_THREAD_DB | |
1615 | thread_db_detach (process); | |
1616 | #endif | |
1617 | ||
1618 | /* Stabilize threads (move out of jump pads). */ | |
1619 | stabilize_threads (); | |
1620 | ||
1621 | /* Detach from the clone lwps first. If the thread group exits just | |
1622 | while we're detaching, we must reap the clone lwps before we're | |
1623 | able to reap the leader. */ | |
1624 | find_inferior (&all_threads, linux_detach_lwp_callback, &pid); | |
1625 | ||
1626 | main_lwp = find_lwp_pid (pid_to_ptid (pid)); | |
1627 | linux_detach_one_lwp (main_lwp); | |
1628 | ||
1629 | the_target->mourn (process); | |
1630 | ||
1631 | /* Since we presently can only stop all lwps of all processes, we | |
1632 | need to unstop lwps of other processes. */ | |
1633 | unstop_all_lwps (0, NULL); | |
1634 | return 0; | |
1635 | } | |
1636 | ||
1637 | /* Remove all LWPs that belong to process PROC from the lwp list. */ | |
1638 | ||
1639 | static int | |
1640 | delete_lwp_callback (struct inferior_list_entry *entry, void *proc) | |
1641 | { | |
1642 | struct thread_info *thread = (struct thread_info *) entry; | |
1643 | struct lwp_info *lwp = get_thread_lwp (thread); | |
1644 | struct process_info *process = (struct process_info *) proc; | |
1645 | ||
1646 | if (pid_of (thread) == pid_of (process)) | |
1647 | delete_lwp (lwp); | |
1648 | ||
1649 | return 0; | |
1650 | } | |
1651 | ||
1652 | static void | |
1653 | linux_mourn (struct process_info *process) | |
1654 | { | |
1655 | struct process_info_private *priv; | |
1656 | ||
1657 | #ifdef USE_THREAD_DB | |
1658 | thread_db_mourn (process); | |
1659 | #endif | |
1660 | ||
1661 | find_inferior (&all_threads, delete_lwp_callback, process); | |
1662 | ||
1663 | /* Freeing all private data. */ | |
1664 | priv = process->priv; | |
1665 | free (priv->arch_private); | |
1666 | free (priv); | |
1667 | process->priv = NULL; | |
1668 | ||
1669 | remove_process (process); | |
1670 | } | |
1671 | ||
1672 | static void | |
1673 | linux_join (int pid) | |
1674 | { | |
1675 | int status, ret; | |
1676 | ||
1677 | do { | |
1678 | ret = my_waitpid (pid, &status, 0); | |
1679 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
1680 | break; | |
1681 | } while (ret != -1 || errno != ECHILD); | |
1682 | } | |
1683 | ||
1684 | /* Return nonzero if the given thread is still alive. */ | |
1685 | static int | |
1686 | linux_thread_alive (ptid_t ptid) | |
1687 | { | |
1688 | struct lwp_info *lwp = find_lwp_pid (ptid); | |
1689 | ||
1690 | /* We assume we always know if a thread exits. If a whole process | |
1691 | exited but we still haven't been able to report it to GDB, we'll | |
1692 | hold on to the last lwp of the dead process. */ | |
1693 | if (lwp != NULL) | |
1694 | return !lwp_is_marked_dead (lwp); | |
1695 | else | |
1696 | return 0; | |
1697 | } | |
1698 | ||
1699 | /* Return 1 if this lwp still has an interesting status pending. If | |
1700 | not (e.g., it had stopped for a breakpoint that is gone), return | |
1701 | false. */ | |
1702 | ||
1703 | static int | |
1704 | thread_still_has_status_pending_p (struct thread_info *thread) | |
1705 | { | |
1706 | struct lwp_info *lp = get_thread_lwp (thread); | |
1707 | ||
1708 | if (!lp->status_pending_p) | |
1709 | return 0; | |
1710 | ||
1711 | if (thread->last_resume_kind != resume_stop | |
1712 | && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
1713 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)) | |
1714 | { | |
1715 | struct thread_info *saved_thread; | |
1716 | CORE_ADDR pc; | |
1717 | int discard = 0; | |
1718 | ||
1719 | gdb_assert (lp->last_status != 0); | |
1720 | ||
1721 | pc = get_pc (lp); | |
1722 | ||
1723 | saved_thread = current_thread; | |
1724 | current_thread = thread; | |
1725 | ||
1726 | if (pc != lp->stop_pc) | |
1727 | { | |
1728 | if (debug_threads) | |
1729 | debug_printf ("PC of %ld changed\n", | |
1730 | lwpid_of (thread)); | |
1731 | discard = 1; | |
1732 | } | |
1733 | ||
1734 | #if !USE_SIGTRAP_SIGINFO | |
1735 | else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
1736 | && !(*the_low_target.breakpoint_at) (pc)) | |
1737 | { | |
1738 | if (debug_threads) | |
1739 | debug_printf ("previous SW breakpoint of %ld gone\n", | |
1740 | lwpid_of (thread)); | |
1741 | discard = 1; | |
1742 | } | |
1743 | else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT | |
1744 | && !hardware_breakpoint_inserted_here (pc)) | |
1745 | { | |
1746 | if (debug_threads) | |
1747 | debug_printf ("previous HW breakpoint of %ld gone\n", | |
1748 | lwpid_of (thread)); | |
1749 | discard = 1; | |
1750 | } | |
1751 | #endif | |
1752 | ||
1753 | current_thread = saved_thread; | |
1754 | ||
1755 | if (discard) | |
1756 | { | |
1757 | if (debug_threads) | |
1758 | debug_printf ("discarding pending breakpoint status\n"); | |
1759 | lp->status_pending_p = 0; | |
1760 | return 0; | |
1761 | } | |
1762 | } | |
1763 | ||
1764 | return 1; | |
1765 | } | |
1766 | ||
1767 | /* Returns true if LWP is resumed from the client's perspective. */ | |
1768 | ||
1769 | static int | |
1770 | lwp_resumed (struct lwp_info *lwp) | |
1771 | { | |
1772 | struct thread_info *thread = get_lwp_thread (lwp); | |
1773 | ||
1774 | if (thread->last_resume_kind != resume_stop) | |
1775 | return 1; | |
1776 | ||
1777 | /* Did gdb send us a `vCont;t', but we haven't reported the | |
1778 | corresponding stop to gdb yet? If so, the thread is still | |
1779 | resumed/running from gdb's perspective. */ | |
1780 | if (thread->last_resume_kind == resume_stop | |
1781 | && thread->last_status.kind == TARGET_WAITKIND_IGNORE) | |
1782 | return 1; | |
1783 | ||
1784 | return 0; | |
1785 | } | |
1786 | ||
1787 | /* Return 1 if this lwp has an interesting status pending. */ | |
1788 | static int | |
1789 | status_pending_p_callback (struct inferior_list_entry *entry, void *arg) | |
1790 | { | |
1791 | struct thread_info *thread = (struct thread_info *) entry; | |
1792 | struct lwp_info *lp = get_thread_lwp (thread); | |
1793 | ptid_t ptid = * (ptid_t *) arg; | |
1794 | ||
1795 | /* Check if we're only interested in events from a specific process | |
1796 | or a specific LWP. */ | |
1797 | if (!ptid_match (ptid_of (thread), ptid)) | |
1798 | return 0; | |
1799 | ||
1800 | if (!lwp_resumed (lp)) | |
1801 | return 0; | |
1802 | ||
1803 | if (lp->status_pending_p | |
1804 | && !thread_still_has_status_pending_p (thread)) | |
1805 | { | |
1806 | linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL); | |
1807 | return 0; | |
1808 | } | |
1809 | ||
1810 | return lp->status_pending_p; | |
1811 | } | |
1812 | ||
1813 | static int | |
1814 | same_lwp (struct inferior_list_entry *entry, void *data) | |
1815 | { | |
1816 | ptid_t ptid = *(ptid_t *) data; | |
1817 | int lwp; | |
1818 | ||
1819 | if (ptid_get_lwp (ptid) != 0) | |
1820 | lwp = ptid_get_lwp (ptid); | |
1821 | else | |
1822 | lwp = ptid_get_pid (ptid); | |
1823 | ||
1824 | if (ptid_get_lwp (entry->id) == lwp) | |
1825 | return 1; | |
1826 | ||
1827 | return 0; | |
1828 | } | |
1829 | ||
1830 | struct lwp_info * | |
1831 | find_lwp_pid (ptid_t ptid) | |
1832 | { | |
1833 | struct inferior_list_entry *thread | |
1834 | = find_inferior (&all_threads, same_lwp, &ptid); | |
1835 | ||
1836 | if (thread == NULL) | |
1837 | return NULL; | |
1838 | ||
1839 | return get_thread_lwp ((struct thread_info *) thread); | |
1840 | } | |
1841 | ||
1842 | /* Return the number of known LWPs in the tgid given by PID. */ | |
1843 | ||
1844 | static int | |
1845 | num_lwps (int pid) | |
1846 | { | |
1847 | struct inferior_list_entry *inf, *tmp; | |
1848 | int count = 0; | |
1849 | ||
1850 | ALL_INFERIORS (&all_threads, inf, tmp) | |
1851 | { | |
1852 | if (ptid_get_pid (inf->id) == pid) | |
1853 | count++; | |
1854 | } | |
1855 | ||
1856 | return count; | |
1857 | } | |
1858 | ||
1859 | /* The arguments passed to iterate_over_lwps. */ | |
1860 | ||
1861 | struct iterate_over_lwps_args | |
1862 | { | |
1863 | /* The FILTER argument passed to iterate_over_lwps. */ | |
1864 | ptid_t filter; | |
1865 | ||
1866 | /* The CALLBACK argument passed to iterate_over_lwps. */ | |
1867 | iterate_over_lwps_ftype *callback; | |
1868 | ||
1869 | /* The DATA argument passed to iterate_over_lwps. */ | |
1870 | void *data; | |
1871 | }; | |
1872 | ||
1873 | /* Callback for find_inferior used by iterate_over_lwps to filter | |
1874 | calls to the callback supplied to that function. Returning a | |
1875 | nonzero value causes find_inferiors to stop iterating and return | |
1876 | the current inferior_list_entry. Returning zero indicates that | |
1877 | find_inferiors should continue iterating. */ | |
1878 | ||
1879 | static int | |
1880 | iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p) | |
1881 | { | |
1882 | struct iterate_over_lwps_args *args | |
1883 | = (struct iterate_over_lwps_args *) args_p; | |
1884 | ||
1885 | if (ptid_match (entry->id, args->filter)) | |
1886 | { | |
1887 | struct thread_info *thr = (struct thread_info *) entry; | |
1888 | struct lwp_info *lwp = get_thread_lwp (thr); | |
1889 | ||
1890 | return (*args->callback) (lwp, args->data); | |
1891 | } | |
1892 | ||
1893 | return 0; | |
1894 | } | |
1895 | ||
1896 | /* See nat/linux-nat.h. */ | |
1897 | ||
1898 | struct lwp_info * | |
1899 | iterate_over_lwps (ptid_t filter, | |
1900 | iterate_over_lwps_ftype callback, | |
1901 | void *data) | |
1902 | { | |
1903 | struct iterate_over_lwps_args args = {filter, callback, data}; | |
1904 | struct inferior_list_entry *entry; | |
1905 | ||
1906 | entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args); | |
1907 | if (entry == NULL) | |
1908 | return NULL; | |
1909 | ||
1910 | return get_thread_lwp ((struct thread_info *) entry); | |
1911 | } | |
1912 | ||
1913 | /* Detect zombie thread group leaders, and "exit" them. We can't reap | |
1914 | their exits until all other threads in the group have exited. */ | |
1915 | ||
1916 | static void | |
1917 | check_zombie_leaders (void) | |
1918 | { | |
1919 | struct process_info *proc, *tmp; | |
1920 | ||
1921 | ALL_PROCESSES (proc, tmp) | |
1922 | { | |
1923 | pid_t leader_pid = pid_of (proc); | |
1924 | struct lwp_info *leader_lp; | |
1925 | ||
1926 | leader_lp = find_lwp_pid (pid_to_ptid (leader_pid)); | |
1927 | ||
1928 | if (debug_threads) | |
1929 | debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, " | |
1930 | "num_lwps=%d, zombie=%d\n", | |
1931 | leader_pid, leader_lp!= NULL, num_lwps (leader_pid), | |
1932 | linux_proc_pid_is_zombie (leader_pid)); | |
1933 | ||
1934 | if (leader_lp != NULL && !leader_lp->stopped | |
1935 | /* Check if there are other threads in the group, as we may | |
1936 | have raced with the inferior simply exiting. */ | |
1937 | && !last_thread_of_process_p (leader_pid) | |
1938 | && linux_proc_pid_is_zombie (leader_pid)) | |
1939 | { | |
1940 | /* A leader zombie can mean one of two things: | |
1941 | ||
1942 | - It exited, and there's an exit status pending | |
1943 | available, or only the leader exited (not the whole | |
1944 | program). In the latter case, we can't waitpid the | |
1945 | leader's exit status until all other threads are gone. | |
1946 | ||
1947 | - There are 3 or more threads in the group, and a thread | |
1948 | other than the leader exec'd. On an exec, the Linux | |
1949 | kernel destroys all other threads (except the execing | |
1950 | one) in the thread group, and resets the execing thread's | |
1951 | tid to the tgid. No exit notification is sent for the | |
1952 | execing thread -- from the ptracer's perspective, it | |
1953 | appears as though the execing thread just vanishes. | |
1954 | Until we reap all other threads except the leader and the | |
1955 | execing thread, the leader will be zombie, and the | |
1956 | execing thread will be in `D (disc sleep)'. As soon as | |
1957 | all other threads are reaped, the execing thread changes | |
1958 | it's tid to the tgid, and the previous (zombie) leader | |
1959 | vanishes, giving place to the "new" leader. We could try | |
1960 | distinguishing the exit and exec cases, by waiting once | |
1961 | more, and seeing if something comes out, but it doesn't | |
1962 | sound useful. The previous leader _does_ go away, and | |
1963 | we'll re-add the new one once we see the exec event | |
1964 | (which is just the same as what would happen if the | |
1965 | previous leader did exit voluntarily before some other | |
1966 | thread execs). */ | |
1967 | ||
1968 | if (debug_threads) | |
1969 | fprintf (stderr, | |
1970 | "CZL: Thread group leader %d zombie " | |
1971 | "(it exited, or another thread execd).\n", | |
1972 | leader_pid); | |
1973 | ||
1974 | delete_lwp (leader_lp); | |
1975 | } | |
1976 | } | |
1977 | } | |
1978 | ||
1979 | /* Callback for `find_inferior'. Returns the first LWP that is not | |
1980 | stopped. ARG is a PTID filter. */ | |
1981 | ||
1982 | static int | |
1983 | not_stopped_callback (struct inferior_list_entry *entry, void *arg) | |
1984 | { | |
1985 | struct thread_info *thr = (struct thread_info *) entry; | |
1986 | struct lwp_info *lwp; | |
1987 | ptid_t filter = *(ptid_t *) arg; | |
1988 | ||
1989 | if (!ptid_match (ptid_of (thr), filter)) | |
1990 | return 0; | |
1991 | ||
1992 | lwp = get_thread_lwp (thr); | |
1993 | if (!lwp->stopped) | |
1994 | return 1; | |
1995 | ||
1996 | return 0; | |
1997 | } | |
1998 | ||
1999 | /* Increment LWP's suspend count. */ | |
2000 | ||
2001 | static void | |
2002 | lwp_suspended_inc (struct lwp_info *lwp) | |
2003 | { | |
2004 | lwp->suspended++; | |
2005 | ||
2006 | if (debug_threads && lwp->suspended > 4) | |
2007 | { | |
2008 | struct thread_info *thread = get_lwp_thread (lwp); | |
2009 | ||
2010 | debug_printf ("LWP %ld has a suspiciously high suspend count," | |
2011 | " suspended=%d\n", lwpid_of (thread), lwp->suspended); | |
2012 | } | |
2013 | } | |
2014 | ||
2015 | /* Decrement LWP's suspend count. */ | |
2016 | ||
2017 | static void | |
2018 | lwp_suspended_decr (struct lwp_info *lwp) | |
2019 | { | |
2020 | lwp->suspended--; | |
2021 | ||
2022 | if (lwp->suspended < 0) | |
2023 | { | |
2024 | struct thread_info *thread = get_lwp_thread (lwp); | |
2025 | ||
2026 | internal_error (__FILE__, __LINE__, | |
2027 | "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread), | |
2028 | lwp->suspended); | |
2029 | } | |
2030 | } | |
2031 | ||
2032 | /* This function should only be called if the LWP got a SIGTRAP. | |
2033 | ||
2034 | Handle any tracepoint steps or hits. Return true if a tracepoint | |
2035 | event was handled, 0 otherwise. */ | |
2036 | ||
2037 | static int | |
2038 | handle_tracepoints (struct lwp_info *lwp) | |
2039 | { | |
2040 | struct thread_info *tinfo = get_lwp_thread (lwp); | |
2041 | int tpoint_related_event = 0; | |
2042 | ||
2043 | gdb_assert (lwp->suspended == 0); | |
2044 | ||
2045 | /* If this tracepoint hit causes a tracing stop, we'll immediately | |
2046 | uninsert tracepoints. To do this, we temporarily pause all | |
2047 | threads, unpatch away, and then unpause threads. We need to make | |
2048 | sure the unpausing doesn't resume LWP too. */ | |
2049 | lwp_suspended_inc (lwp); | |
2050 | ||
2051 | /* And we need to be sure that any all-threads-stopping doesn't try | |
2052 | to move threads out of the jump pads, as it could deadlock the | |
2053 | inferior (LWP could be in the jump pad, maybe even holding the | |
2054 | lock.) */ | |
2055 | ||
2056 | /* Do any necessary step collect actions. */ | |
2057 | tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc); | |
2058 | ||
2059 | tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc); | |
2060 | ||
2061 | /* See if we just hit a tracepoint and do its main collect | |
2062 | actions. */ | |
2063 | tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc); | |
2064 | ||
2065 | lwp_suspended_decr (lwp); | |
2066 | ||
2067 | gdb_assert (lwp->suspended == 0); | |
2068 | gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint); | |
2069 | ||
2070 | if (tpoint_related_event) | |
2071 | { | |
2072 | if (debug_threads) | |
2073 | debug_printf ("got a tracepoint event\n"); | |
2074 | return 1; | |
2075 | } | |
2076 | ||
2077 | return 0; | |
2078 | } | |
2079 | ||
2080 | /* Convenience wrapper. Returns true if LWP is presently collecting a | |
2081 | fast tracepoint. */ | |
2082 | ||
2083 | static int | |
2084 | linux_fast_tracepoint_collecting (struct lwp_info *lwp, | |
2085 | struct fast_tpoint_collect_status *status) | |
2086 | { | |
2087 | CORE_ADDR thread_area; | |
2088 | struct thread_info *thread = get_lwp_thread (lwp); | |
2089 | ||
2090 | if (the_low_target.get_thread_area == NULL) | |
2091 | return 0; | |
2092 | ||
2093 | /* Get the thread area address. This is used to recognize which | |
2094 | thread is which when tracing with the in-process agent library. | |
2095 | We don't read anything from the address, and treat it as opaque; | |
2096 | it's the address itself that we assume is unique per-thread. */ | |
2097 | if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1) | |
2098 | return 0; | |
2099 | ||
2100 | return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status); | |
2101 | } | |
2102 | ||
2103 | /* The reason we resume in the caller, is because we want to be able | |
2104 | to pass lwp->status_pending as WSTAT, and we need to clear | |
2105 | status_pending_p before resuming, otherwise, linux_resume_one_lwp | |
2106 | refuses to resume. */ | |
2107 | ||
2108 | static int | |
2109 | maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat) | |
2110 | { | |
2111 | struct thread_info *saved_thread; | |
2112 | ||
2113 | saved_thread = current_thread; | |
2114 | current_thread = get_lwp_thread (lwp); | |
2115 | ||
2116 | if ((wstat == NULL | |
2117 | || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP)) | |
2118 | && supports_fast_tracepoints () | |
2119 | && agent_loaded_p ()) | |
2120 | { | |
2121 | struct fast_tpoint_collect_status status; | |
2122 | int r; | |
2123 | ||
2124 | if (debug_threads) | |
2125 | debug_printf ("Checking whether LWP %ld needs to move out of the " | |
2126 | "jump pad.\n", | |
2127 | lwpid_of (current_thread)); | |
2128 | ||
2129 | r = linux_fast_tracepoint_collecting (lwp, &status); | |
2130 | ||
2131 | if (wstat == NULL | |
2132 | || (WSTOPSIG (*wstat) != SIGILL | |
2133 | && WSTOPSIG (*wstat) != SIGFPE | |
2134 | && WSTOPSIG (*wstat) != SIGSEGV | |
2135 | && WSTOPSIG (*wstat) != SIGBUS)) | |
2136 | { | |
2137 | lwp->collecting_fast_tracepoint = r; | |
2138 | ||
2139 | if (r != 0) | |
2140 | { | |
2141 | if (r == 1 && lwp->exit_jump_pad_bkpt == NULL) | |
2142 | { | |
2143 | /* Haven't executed the original instruction yet. | |
2144 | Set breakpoint there, and wait till it's hit, | |
2145 | then single-step until exiting the jump pad. */ | |
2146 | lwp->exit_jump_pad_bkpt | |
2147 | = set_breakpoint_at (status.adjusted_insn_addr, NULL); | |
2148 | } | |
2149 | ||
2150 | if (debug_threads) | |
2151 | debug_printf ("Checking whether LWP %ld needs to move out of " | |
2152 | "the jump pad...it does\n", | |
2153 | lwpid_of (current_thread)); | |
2154 | current_thread = saved_thread; | |
2155 | ||
2156 | return 1; | |
2157 | } | |
2158 | } | |
2159 | else | |
2160 | { | |
2161 | /* If we get a synchronous signal while collecting, *and* | |
2162 | while executing the (relocated) original instruction, | |
2163 | reset the PC to point at the tpoint address, before | |
2164 | reporting to GDB. Otherwise, it's an IPA lib bug: just | |
2165 | report the signal to GDB, and pray for the best. */ | |
2166 | ||
2167 | lwp->collecting_fast_tracepoint = 0; | |
2168 | ||
2169 | if (r != 0 | |
2170 | && (status.adjusted_insn_addr <= lwp->stop_pc | |
2171 | && lwp->stop_pc < status.adjusted_insn_addr_end)) | |
2172 | { | |
2173 | siginfo_t info; | |
2174 | struct regcache *regcache; | |
2175 | ||
2176 | /* The si_addr on a few signals references the address | |
2177 | of the faulting instruction. Adjust that as | |
2178 | well. */ | |
2179 | if ((WSTOPSIG (*wstat) == SIGILL | |
2180 | || WSTOPSIG (*wstat) == SIGFPE | |
2181 | || WSTOPSIG (*wstat) == SIGBUS | |
2182 | || WSTOPSIG (*wstat) == SIGSEGV) | |
2183 | && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread), | |
2184 | (PTRACE_TYPE_ARG3) 0, &info) == 0 | |
2185 | /* Final check just to make sure we don't clobber | |
2186 | the siginfo of non-kernel-sent signals. */ | |
2187 | && (uintptr_t) info.si_addr == lwp->stop_pc) | |
2188 | { | |
2189 | info.si_addr = (void *) (uintptr_t) status.tpoint_addr; | |
2190 | ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread), | |
2191 | (PTRACE_TYPE_ARG3) 0, &info); | |
2192 | } | |
2193 | ||
2194 | regcache = get_thread_regcache (current_thread, 1); | |
2195 | (*the_low_target.set_pc) (regcache, status.tpoint_addr); | |
2196 | lwp->stop_pc = status.tpoint_addr; | |
2197 | ||
2198 | /* Cancel any fast tracepoint lock this thread was | |
2199 | holding. */ | |
2200 | force_unlock_trace_buffer (); | |
2201 | } | |
2202 | ||
2203 | if (lwp->exit_jump_pad_bkpt != NULL) | |
2204 | { | |
2205 | if (debug_threads) | |
2206 | debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. " | |
2207 | "stopping all threads momentarily.\n"); | |
2208 | ||
2209 | stop_all_lwps (1, lwp); | |
2210 | ||
2211 | delete_breakpoint (lwp->exit_jump_pad_bkpt); | |
2212 | lwp->exit_jump_pad_bkpt = NULL; | |
2213 | ||
2214 | unstop_all_lwps (1, lwp); | |
2215 | ||
2216 | gdb_assert (lwp->suspended >= 0); | |
2217 | } | |
2218 | } | |
2219 | } | |
2220 | ||
2221 | if (debug_threads) | |
2222 | debug_printf ("Checking whether LWP %ld needs to move out of the " | |
2223 | "jump pad...no\n", | |
2224 | lwpid_of (current_thread)); | |
2225 | ||
2226 | current_thread = saved_thread; | |
2227 | return 0; | |
2228 | } | |
2229 | ||
2230 | /* Enqueue one signal in the "signals to report later when out of the | |
2231 | jump pad" list. */ | |
2232 | ||
2233 | static void | |
2234 | enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat) | |
2235 | { | |
2236 | struct pending_signals *p_sig; | |
2237 | struct thread_info *thread = get_lwp_thread (lwp); | |
2238 | ||
2239 | if (debug_threads) | |
2240 | debug_printf ("Deferring signal %d for LWP %ld.\n", | |
2241 | WSTOPSIG (*wstat), lwpid_of (thread)); | |
2242 | ||
2243 | if (debug_threads) | |
2244 | { | |
2245 | struct pending_signals *sig; | |
2246 | ||
2247 | for (sig = lwp->pending_signals_to_report; | |
2248 | sig != NULL; | |
2249 | sig = sig->prev) | |
2250 | debug_printf (" Already queued %d\n", | |
2251 | sig->signal); | |
2252 | ||
2253 | debug_printf (" (no more currently queued signals)\n"); | |
2254 | } | |
2255 | ||
2256 | /* Don't enqueue non-RT signals if they are already in the deferred | |
2257 | queue. (SIGSTOP being the easiest signal to see ending up here | |
2258 | twice) */ | |
2259 | if (WSTOPSIG (*wstat) < __SIGRTMIN) | |
2260 | { | |
2261 | struct pending_signals *sig; | |
2262 | ||
2263 | for (sig = lwp->pending_signals_to_report; | |
2264 | sig != NULL; | |
2265 | sig = sig->prev) | |
2266 | { | |
2267 | if (sig->signal == WSTOPSIG (*wstat)) | |
2268 | { | |
2269 | if (debug_threads) | |
2270 | debug_printf ("Not requeuing already queued non-RT signal %d" | |
2271 | " for LWP %ld\n", | |
2272 | sig->signal, | |
2273 | lwpid_of (thread)); | |
2274 | return; | |
2275 | } | |
2276 | } | |
2277 | } | |
2278 | ||
2279 | p_sig = XCNEW (struct pending_signals); | |
2280 | p_sig->prev = lwp->pending_signals_to_report; | |
2281 | p_sig->signal = WSTOPSIG (*wstat); | |
2282 | ||
2283 | ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0, | |
2284 | &p_sig->info); | |
2285 | ||
2286 | lwp->pending_signals_to_report = p_sig; | |
2287 | } | |
2288 | ||
2289 | /* Dequeue one signal from the "signals to report later when out of | |
2290 | the jump pad" list. */ | |
2291 | ||
2292 | static int | |
2293 | dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat) | |
2294 | { | |
2295 | struct thread_info *thread = get_lwp_thread (lwp); | |
2296 | ||
2297 | if (lwp->pending_signals_to_report != NULL) | |
2298 | { | |
2299 | struct pending_signals **p_sig; | |
2300 | ||
2301 | p_sig = &lwp->pending_signals_to_report; | |
2302 | while ((*p_sig)->prev != NULL) | |
2303 | p_sig = &(*p_sig)->prev; | |
2304 | ||
2305 | *wstat = W_STOPCODE ((*p_sig)->signal); | |
2306 | if ((*p_sig)->info.si_signo != 0) | |
2307 | ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0, | |
2308 | &(*p_sig)->info); | |
2309 | free (*p_sig); | |
2310 | *p_sig = NULL; | |
2311 | ||
2312 | if (debug_threads) | |
2313 | debug_printf ("Reporting deferred signal %d for LWP %ld.\n", | |
2314 | WSTOPSIG (*wstat), lwpid_of (thread)); | |
2315 | ||
2316 | if (debug_threads) | |
2317 | { | |
2318 | struct pending_signals *sig; | |
2319 | ||
2320 | for (sig = lwp->pending_signals_to_report; | |
2321 | sig != NULL; | |
2322 | sig = sig->prev) | |
2323 | debug_printf (" Still queued %d\n", | |
2324 | sig->signal); | |
2325 | ||
2326 | debug_printf (" (no more queued signals)\n"); | |
2327 | } | |
2328 | ||
2329 | return 1; | |
2330 | } | |
2331 | ||
2332 | return 0; | |
2333 | } | |
2334 | ||
2335 | /* Fetch the possibly triggered data watchpoint info and store it in | |
2336 | CHILD. | |
2337 | ||
2338 | On some archs, like x86, that use debug registers to set | |
2339 | watchpoints, it's possible that the way to know which watched | |
2340 | address trapped, is to check the register that is used to select | |
2341 | which address to watch. Problem is, between setting the watchpoint | |
2342 | and reading back which data address trapped, the user may change | |
2343 | the set of watchpoints, and, as a consequence, GDB changes the | |
2344 | debug registers in the inferior. To avoid reading back a stale | |
2345 | stopped-data-address when that happens, we cache in LP the fact | |
2346 | that a watchpoint trapped, and the corresponding data address, as | |
2347 | soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug | |
2348 | registers meanwhile, we have the cached data we can rely on. */ | |
2349 | ||
2350 | static int | |
2351 | check_stopped_by_watchpoint (struct lwp_info *child) | |
2352 | { | |
2353 | if (the_low_target.stopped_by_watchpoint != NULL) | |
2354 | { | |
2355 | struct thread_info *saved_thread; | |
2356 | ||
2357 | saved_thread = current_thread; | |
2358 | current_thread = get_lwp_thread (child); | |
2359 | ||
2360 | if (the_low_target.stopped_by_watchpoint ()) | |
2361 | { | |
2362 | child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; | |
2363 | ||
2364 | if (the_low_target.stopped_data_address != NULL) | |
2365 | child->stopped_data_address | |
2366 | = the_low_target.stopped_data_address (); | |
2367 | else | |
2368 | child->stopped_data_address = 0; | |
2369 | } | |
2370 | ||
2371 | current_thread = saved_thread; | |
2372 | } | |
2373 | ||
2374 | return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; | |
2375 | } | |
2376 | ||
2377 | /* Return the ptrace options that we want to try to enable. */ | |
2378 | ||
2379 | static int | |
2380 | linux_low_ptrace_options (int attached) | |
2381 | { | |
2382 | int options = 0; | |
2383 | ||
2384 | if (!attached) | |
2385 | options |= PTRACE_O_EXITKILL; | |
2386 | ||
2387 | if (report_fork_events) | |
2388 | options |= PTRACE_O_TRACEFORK; | |
2389 | ||
2390 | if (report_vfork_events) | |
2391 | options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE); | |
2392 | ||
2393 | if (report_exec_events) | |
2394 | options |= PTRACE_O_TRACEEXEC; | |
2395 | ||
2396 | options |= PTRACE_O_TRACESYSGOOD; | |
2397 | ||
2398 | return options; | |
2399 | } | |
2400 | ||
2401 | /* Do low-level handling of the event, and check if we should go on | |
2402 | and pass it to caller code. Return the affected lwp if we are, or | |
2403 | NULL otherwise. */ | |
2404 | ||
2405 | static struct lwp_info * | |
2406 | linux_low_filter_event (int lwpid, int wstat) | |
2407 | { | |
2408 | struct lwp_info *child; | |
2409 | struct thread_info *thread; | |
2410 | int have_stop_pc = 0; | |
2411 | ||
2412 | child = find_lwp_pid (pid_to_ptid (lwpid)); | |
2413 | ||
2414 | /* Check for stop events reported by a process we didn't already | |
2415 | know about - anything not already in our LWP list. | |
2416 | ||
2417 | If we're expecting to receive stopped processes after | |
2418 | fork, vfork, and clone events, then we'll just add the | |
2419 | new one to our list and go back to waiting for the event | |
2420 | to be reported - the stopped process might be returned | |
2421 | from waitpid before or after the event is. | |
2422 | ||
2423 | But note the case of a non-leader thread exec'ing after the | |
2424 | leader having exited, and gone from our lists (because | |
2425 | check_zombie_leaders deleted it). The non-leader thread | |
2426 | changes its tid to the tgid. */ | |
2427 | ||
2428 | if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP | |
2429 | && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC) | |
2430 | { | |
2431 | ptid_t child_ptid; | |
2432 | ||
2433 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2434 | if (debug_threads) | |
2435 | { | |
2436 | debug_printf ("LLW: Re-adding thread group leader LWP %d" | |
2437 | "after exec.\n", lwpid); | |
2438 | } | |
2439 | ||
2440 | child_ptid = ptid_build (lwpid, lwpid, 0); | |
2441 | child = add_lwp (child_ptid); | |
2442 | child->stopped = 1; | |
2443 | current_thread = child->thread; | |
2444 | } | |
2445 | ||
2446 | /* If we didn't find a process, one of two things presumably happened: | |
2447 | - A process we started and then detached from has exited. Ignore it. | |
2448 | - A process we are controlling has forked and the new child's stop | |
2449 | was reported to us by the kernel. Save its PID. */ | |
2450 | if (child == NULL && WIFSTOPPED (wstat)) | |
2451 | { | |
2452 | add_to_pid_list (&stopped_pids, lwpid, wstat); | |
2453 | return NULL; | |
2454 | } | |
2455 | else if (child == NULL) | |
2456 | return NULL; | |
2457 | ||
2458 | thread = get_lwp_thread (child); | |
2459 | ||
2460 | child->stopped = 1; | |
2461 | ||
2462 | child->last_status = wstat; | |
2463 | ||
2464 | /* Check if the thread has exited. */ | |
2465 | if ((WIFEXITED (wstat) || WIFSIGNALED (wstat))) | |
2466 | { | |
2467 | if (debug_threads) | |
2468 | debug_printf ("LLFE: %d exited.\n", lwpid); | |
2469 | ||
2470 | if (finish_step_over (child)) | |
2471 | { | |
2472 | /* Unsuspend all other LWPs, and set them back running again. */ | |
2473 | unsuspend_all_lwps (child); | |
2474 | } | |
2475 | ||
2476 | /* If there is at least one more LWP, then the exit signal was | |
2477 | not the end of the debugged application and should be | |
2478 | ignored, unless GDB wants to hear about thread exits. */ | |
2479 | if (report_thread_events | |
2480 | || last_thread_of_process_p (pid_of (thread))) | |
2481 | { | |
2482 | /* Since events are serialized to GDB core, and we can't | |
2483 | report this one right now. Leave the status pending for | |
2484 | the next time we're able to report it. */ | |
2485 | mark_lwp_dead (child, wstat); | |
2486 | return child; | |
2487 | } | |
2488 | else | |
2489 | { | |
2490 | delete_lwp (child); | |
2491 | return NULL; | |
2492 | } | |
2493 | } | |
2494 | ||
2495 | gdb_assert (WIFSTOPPED (wstat)); | |
2496 | ||
2497 | if (WIFSTOPPED (wstat)) | |
2498 | { | |
2499 | struct process_info *proc; | |
2500 | ||
2501 | /* Architecture-specific setup after inferior is running. */ | |
2502 | proc = find_process_pid (pid_of (thread)); | |
2503 | if (proc->tdesc == NULL) | |
2504 | { | |
2505 | if (proc->attached) | |
2506 | { | |
2507 | /* This needs to happen after we have attached to the | |
2508 | inferior and it is stopped for the first time, but | |
2509 | before we access any inferior registers. */ | |
2510 | linux_arch_setup_thread (thread); | |
2511 | } | |
2512 | else | |
2513 | { | |
2514 | /* The process is started, but GDBserver will do | |
2515 | architecture-specific setup after the program stops at | |
2516 | the first instruction. */ | |
2517 | child->status_pending_p = 1; | |
2518 | child->status_pending = wstat; | |
2519 | return child; | |
2520 | } | |
2521 | } | |
2522 | } | |
2523 | ||
2524 | if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags) | |
2525 | { | |
2526 | struct process_info *proc = find_process_pid (pid_of (thread)); | |
2527 | int options = linux_low_ptrace_options (proc->attached); | |
2528 | ||
2529 | linux_enable_event_reporting (lwpid, options); | |
2530 | child->must_set_ptrace_flags = 0; | |
2531 | } | |
2532 | ||
2533 | /* Always update syscall_state, even if it will be filtered later. */ | |
2534 | if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP) | |
2535 | { | |
2536 | child->syscall_state | |
2537 | = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
2538 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
2539 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
2540 | } | |
2541 | else | |
2542 | { | |
2543 | /* Almost all other ptrace-stops are known to be outside of system | |
2544 | calls, with further exceptions in handle_extended_wait. */ | |
2545 | child->syscall_state = TARGET_WAITKIND_IGNORE; | |
2546 | } | |
2547 | ||
2548 | /* Be careful to not overwrite stop_pc until save_stop_reason is | |
2549 | called. */ | |
2550 | if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP | |
2551 | && linux_is_extended_waitstatus (wstat)) | |
2552 | { | |
2553 | child->stop_pc = get_pc (child); | |
2554 | if (handle_extended_wait (&child, wstat)) | |
2555 | { | |
2556 | /* The event has been handled, so just return without | |
2557 | reporting it. */ | |
2558 | return NULL; | |
2559 | } | |
2560 | } | |
2561 | ||
2562 | if (linux_wstatus_maybe_breakpoint (wstat)) | |
2563 | { | |
2564 | if (save_stop_reason (child)) | |
2565 | have_stop_pc = 1; | |
2566 | } | |
2567 | ||
2568 | if (!have_stop_pc) | |
2569 | child->stop_pc = get_pc (child); | |
2570 | ||
2571 | if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP | |
2572 | && child->stop_expected) | |
2573 | { | |
2574 | if (debug_threads) | |
2575 | debug_printf ("Expected stop.\n"); | |
2576 | child->stop_expected = 0; | |
2577 | ||
2578 | if (thread->last_resume_kind == resume_stop) | |
2579 | { | |
2580 | /* We want to report the stop to the core. Treat the | |
2581 | SIGSTOP as a normal event. */ | |
2582 | if (debug_threads) | |
2583 | debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n", | |
2584 | target_pid_to_str (ptid_of (thread))); | |
2585 | } | |
2586 | else if (stopping_threads != NOT_STOPPING_THREADS) | |
2587 | { | |
2588 | /* Stopping threads. We don't want this SIGSTOP to end up | |
2589 | pending. */ | |
2590 | if (debug_threads) | |
2591 | debug_printf ("LLW: SIGSTOP caught for %s " | |
2592 | "while stopping threads.\n", | |
2593 | target_pid_to_str (ptid_of (thread))); | |
2594 | return NULL; | |
2595 | } | |
2596 | else | |
2597 | { | |
2598 | /* This is a delayed SIGSTOP. Filter out the event. */ | |
2599 | if (debug_threads) | |
2600 | debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n", | |
2601 | child->stepping ? "step" : "continue", | |
2602 | target_pid_to_str (ptid_of (thread))); | |
2603 | ||
2604 | linux_resume_one_lwp (child, child->stepping, 0, NULL); | |
2605 | return NULL; | |
2606 | } | |
2607 | } | |
2608 | ||
2609 | child->status_pending_p = 1; | |
2610 | child->status_pending = wstat; | |
2611 | return child; | |
2612 | } | |
2613 | ||
2614 | /* Return true if THREAD is doing hardware single step. */ | |
2615 | ||
2616 | static int | |
2617 | maybe_hw_step (struct thread_info *thread) | |
2618 | { | |
2619 | if (can_hardware_single_step ()) | |
2620 | return 1; | |
2621 | else | |
2622 | { | |
2623 | /* GDBserver must insert reinsert breakpoint for software | |
2624 | single step. */ | |
2625 | gdb_assert (has_reinsert_breakpoints (thread)); | |
2626 | return 0; | |
2627 | } | |
2628 | } | |
2629 | ||
2630 | /* Resume LWPs that are currently stopped without any pending status | |
2631 | to report, but are resumed from the core's perspective. */ | |
2632 | ||
2633 | static void | |
2634 | resume_stopped_resumed_lwps (struct inferior_list_entry *entry) | |
2635 | { | |
2636 | struct thread_info *thread = (struct thread_info *) entry; | |
2637 | struct lwp_info *lp = get_thread_lwp (thread); | |
2638 | ||
2639 | if (lp->stopped | |
2640 | && !lp->suspended | |
2641 | && !lp->status_pending_p | |
2642 | && thread->last_status.kind == TARGET_WAITKIND_IGNORE) | |
2643 | { | |
2644 | int step = thread->last_resume_kind == resume_step; | |
2645 | ||
2646 | if (debug_threads) | |
2647 | debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n", | |
2648 | target_pid_to_str (ptid_of (thread)), | |
2649 | paddress (lp->stop_pc), | |
2650 | step); | |
2651 | ||
2652 | linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL); | |
2653 | } | |
2654 | } | |
2655 | ||
2656 | /* Wait for an event from child(ren) WAIT_PTID, and return any that | |
2657 | match FILTER_PTID (leaving others pending). The PTIDs can be: | |
2658 | minus_one_ptid, to specify any child; a pid PTID, specifying all | |
2659 | lwps of a thread group; or a PTID representing a single lwp. Store | |
2660 | the stop status through the status pointer WSTAT. OPTIONS is | |
2661 | passed to the waitpid call. Return 0 if no event was found and | |
2662 | OPTIONS contains WNOHANG. Return -1 if no unwaited-for children | |
2663 | was found. Return the PID of the stopped child otherwise. */ | |
2664 | ||
2665 | static int | |
2666 | linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid, | |
2667 | int *wstatp, int options) | |
2668 | { | |
2669 | struct thread_info *event_thread; | |
2670 | struct lwp_info *event_child, *requested_child; | |
2671 | sigset_t block_mask, prev_mask; | |
2672 | ||
2673 | retry: | |
2674 | /* N.B. event_thread points to the thread_info struct that contains | |
2675 | event_child. Keep them in sync. */ | |
2676 | event_thread = NULL; | |
2677 | event_child = NULL; | |
2678 | requested_child = NULL; | |
2679 | ||
2680 | /* Check for a lwp with a pending status. */ | |
2681 | ||
2682 | if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid)) | |
2683 | { | |
2684 | event_thread = (struct thread_info *) | |
2685 | find_inferior (&all_threads, status_pending_p_callback, &filter_ptid); | |
2686 | if (event_thread != NULL) | |
2687 | event_child = get_thread_lwp (event_thread); | |
2688 | if (debug_threads && event_thread) | |
2689 | debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread)); | |
2690 | } | |
2691 | else if (!ptid_equal (filter_ptid, null_ptid)) | |
2692 | { | |
2693 | requested_child = find_lwp_pid (filter_ptid); | |
2694 | ||
2695 | if (stopping_threads == NOT_STOPPING_THREADS | |
2696 | && requested_child->status_pending_p | |
2697 | && requested_child->collecting_fast_tracepoint) | |
2698 | { | |
2699 | enqueue_one_deferred_signal (requested_child, | |
2700 | &requested_child->status_pending); | |
2701 | requested_child->status_pending_p = 0; | |
2702 | requested_child->status_pending = 0; | |
2703 | linux_resume_one_lwp (requested_child, 0, 0, NULL); | |
2704 | } | |
2705 | ||
2706 | if (requested_child->suspended | |
2707 | && requested_child->status_pending_p) | |
2708 | { | |
2709 | internal_error (__FILE__, __LINE__, | |
2710 | "requesting an event out of a" | |
2711 | " suspended child?"); | |
2712 | } | |
2713 | ||
2714 | if (requested_child->status_pending_p) | |
2715 | { | |
2716 | event_child = requested_child; | |
2717 | event_thread = get_lwp_thread (event_child); | |
2718 | } | |
2719 | } | |
2720 | ||
2721 | if (event_child != NULL) | |
2722 | { | |
2723 | if (debug_threads) | |
2724 | debug_printf ("Got an event from pending child %ld (%04x)\n", | |
2725 | lwpid_of (event_thread), event_child->status_pending); | |
2726 | *wstatp = event_child->status_pending; | |
2727 | event_child->status_pending_p = 0; | |
2728 | event_child->status_pending = 0; | |
2729 | current_thread = event_thread; | |
2730 | return lwpid_of (event_thread); | |
2731 | } | |
2732 | ||
2733 | /* But if we don't find a pending event, we'll have to wait. | |
2734 | ||
2735 | We only enter this loop if no process has a pending wait status. | |
2736 | Thus any action taken in response to a wait status inside this | |
2737 | loop is responding as soon as we detect the status, not after any | |
2738 | pending events. */ | |
2739 | ||
2740 | /* Make sure SIGCHLD is blocked until the sigsuspend below. Block | |
2741 | all signals while here. */ | |
2742 | sigfillset (&block_mask); | |
2743 | sigprocmask (SIG_BLOCK, &block_mask, &prev_mask); | |
2744 | ||
2745 | /* Always pull all events out of the kernel. We'll randomly select | |
2746 | an event LWP out of all that have events, to prevent | |
2747 | starvation. */ | |
2748 | while (event_child == NULL) | |
2749 | { | |
2750 | pid_t ret = 0; | |
2751 | ||
2752 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace | |
2753 | quirks: | |
2754 | ||
2755 | - If the thread group leader exits while other threads in the | |
2756 | thread group still exist, waitpid(TGID, ...) hangs. That | |
2757 | waitpid won't return an exit status until the other threads | |
2758 | in the group are reaped. | |
2759 | ||
2760 | - When a non-leader thread execs, that thread just vanishes | |
2761 | without reporting an exit (so we'd hang if we waited for it | |
2762 | explicitly in that case). The exec event is reported to | |
2763 | the TGID pid. */ | |
2764 | errno = 0; | |
2765 | ret = my_waitpid (-1, wstatp, options | WNOHANG); | |
2766 | ||
2767 | if (debug_threads) | |
2768 | debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n", | |
2769 | ret, errno ? strerror (errno) : "ERRNO-OK"); | |
2770 | ||
2771 | if (ret > 0) | |
2772 | { | |
2773 | if (debug_threads) | |
2774 | { | |
2775 | debug_printf ("LLW: waitpid %ld received %s\n", | |
2776 | (long) ret, status_to_str (*wstatp)); | |
2777 | } | |
2778 | ||
2779 | /* Filter all events. IOW, leave all events pending. We'll | |
2780 | randomly select an event LWP out of all that have events | |
2781 | below. */ | |
2782 | linux_low_filter_event (ret, *wstatp); | |
2783 | /* Retry until nothing comes out of waitpid. A single | |
2784 | SIGCHLD can indicate more than one child stopped. */ | |
2785 | continue; | |
2786 | } | |
2787 | ||
2788 | /* Now that we've pulled all events out of the kernel, resume | |
2789 | LWPs that don't have an interesting event to report. */ | |
2790 | if (stopping_threads == NOT_STOPPING_THREADS) | |
2791 | for_each_inferior (&all_threads, resume_stopped_resumed_lwps); | |
2792 | ||
2793 | /* ... and find an LWP with a status to report to the core, if | |
2794 | any. */ | |
2795 | event_thread = (struct thread_info *) | |
2796 | find_inferior (&all_threads, status_pending_p_callback, &filter_ptid); | |
2797 | if (event_thread != NULL) | |
2798 | { | |
2799 | event_child = get_thread_lwp (event_thread); | |
2800 | *wstatp = event_child->status_pending; | |
2801 | event_child->status_pending_p = 0; | |
2802 | event_child->status_pending = 0; | |
2803 | break; | |
2804 | } | |
2805 | ||
2806 | /* Check for zombie thread group leaders. Those can't be reaped | |
2807 | until all other threads in the thread group are. */ | |
2808 | check_zombie_leaders (); | |
2809 | ||
2810 | /* If there are no resumed children left in the set of LWPs we | |
2811 | want to wait for, bail. We can't just block in | |
2812 | waitpid/sigsuspend, because lwps might have been left stopped | |
2813 | in trace-stop state, and we'd be stuck forever waiting for | |
2814 | their status to change (which would only happen if we resumed | |
2815 | them). Even if WNOHANG is set, this return code is preferred | |
2816 | over 0 (below), as it is more detailed. */ | |
2817 | if ((find_inferior (&all_threads, | |
2818 | not_stopped_callback, | |
2819 | &wait_ptid) == NULL)) | |
2820 | { | |
2821 | if (debug_threads) | |
2822 | debug_printf ("LLW: exit (no unwaited-for LWP)\n"); | |
2823 | sigprocmask (SIG_SETMASK, &prev_mask, NULL); | |
2824 | return -1; | |
2825 | } | |
2826 | ||
2827 | /* No interesting event to report to the caller. */ | |
2828 | if ((options & WNOHANG)) | |
2829 | { | |
2830 | if (debug_threads) | |
2831 | debug_printf ("WNOHANG set, no event found\n"); | |
2832 | ||
2833 | sigprocmask (SIG_SETMASK, &prev_mask, NULL); | |
2834 | return 0; | |
2835 | } | |
2836 | ||
2837 | /* Block until we get an event reported with SIGCHLD. */ | |
2838 | if (debug_threads) | |
2839 | debug_printf ("sigsuspend'ing\n"); | |
2840 | ||
2841 | sigsuspend (&prev_mask); | |
2842 | sigprocmask (SIG_SETMASK, &prev_mask, NULL); | |
2843 | goto retry; | |
2844 | } | |
2845 | ||
2846 | sigprocmask (SIG_SETMASK, &prev_mask, NULL); | |
2847 | ||
2848 | current_thread = event_thread; | |
2849 | ||
2850 | return lwpid_of (event_thread); | |
2851 | } | |
2852 | ||
2853 | /* Wait for an event from child(ren) PTID. PTIDs can be: | |
2854 | minus_one_ptid, to specify any child; a pid PTID, specifying all | |
2855 | lwps of a thread group; or a PTID representing a single lwp. Store | |
2856 | the stop status through the status pointer WSTAT. OPTIONS is | |
2857 | passed to the waitpid call. Return 0 if no event was found and | |
2858 | OPTIONS contains WNOHANG. Return -1 if no unwaited-for children | |
2859 | was found. Return the PID of the stopped child otherwise. */ | |
2860 | ||
2861 | static int | |
2862 | linux_wait_for_event (ptid_t ptid, int *wstatp, int options) | |
2863 | { | |
2864 | return linux_wait_for_event_filtered (ptid, ptid, wstatp, options); | |
2865 | } | |
2866 | ||
2867 | /* Count the LWP's that have had events. */ | |
2868 | ||
2869 | static int | |
2870 | count_events_callback (struct inferior_list_entry *entry, void *data) | |
2871 | { | |
2872 | struct thread_info *thread = (struct thread_info *) entry; | |
2873 | struct lwp_info *lp = get_thread_lwp (thread); | |
2874 | int *count = (int *) data; | |
2875 | ||
2876 | gdb_assert (count != NULL); | |
2877 | ||
2878 | /* Count only resumed LWPs that have an event pending. */ | |
2879 | if (thread->last_status.kind == TARGET_WAITKIND_IGNORE | |
2880 | && lp->status_pending_p) | |
2881 | (*count)++; | |
2882 | ||
2883 | return 0; | |
2884 | } | |
2885 | ||
2886 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2887 | ||
2888 | static int | |
2889 | select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data) | |
2890 | { | |
2891 | struct thread_info *thread = (struct thread_info *) entry; | |
2892 | struct lwp_info *lp = get_thread_lwp (thread); | |
2893 | ||
2894 | if (thread->last_status.kind == TARGET_WAITKIND_IGNORE | |
2895 | && thread->last_resume_kind == resume_step | |
2896 | && lp->status_pending_p) | |
2897 | return 1; | |
2898 | else | |
2899 | return 0; | |
2900 | } | |
2901 | ||
2902 | /* Select the Nth LWP that has had an event. */ | |
2903 | ||
2904 | static int | |
2905 | select_event_lwp_callback (struct inferior_list_entry *entry, void *data) | |
2906 | { | |
2907 | struct thread_info *thread = (struct thread_info *) entry; | |
2908 | struct lwp_info *lp = get_thread_lwp (thread); | |
2909 | int *selector = (int *) data; | |
2910 | ||
2911 | gdb_assert (selector != NULL); | |
2912 | ||
2913 | /* Select only resumed LWPs that have an event pending. */ | |
2914 | if (thread->last_status.kind == TARGET_WAITKIND_IGNORE | |
2915 | && lp->status_pending_p) | |
2916 | if ((*selector)-- == 0) | |
2917 | return 1; | |
2918 | ||
2919 | return 0; | |
2920 | } | |
2921 | ||
2922 | /* Select one LWP out of those that have events pending. */ | |
2923 | ||
2924 | static void | |
2925 | select_event_lwp (struct lwp_info **orig_lp) | |
2926 | { | |
2927 | int num_events = 0; | |
2928 | int random_selector; | |
2929 | struct thread_info *event_thread = NULL; | |
2930 | ||
2931 | /* In all-stop, give preference to the LWP that is being | |
2932 | single-stepped. There will be at most one, and it's the LWP that | |
2933 | the core is most interested in. If we didn't do this, then we'd | |
2934 | have to handle pending step SIGTRAPs somehow in case the core | |
2935 | later continues the previously-stepped thread, otherwise we'd | |
2936 | report the pending SIGTRAP, and the core, not having stepped the | |
2937 | thread, wouldn't understand what the trap was for, and therefore | |
2938 | would report it to the user as a random signal. */ | |
2939 | if (!non_stop) | |
2940 | { | |
2941 | event_thread | |
2942 | = (struct thread_info *) find_inferior (&all_threads, | |
2943 | select_singlestep_lwp_callback, | |
2944 | NULL); | |
2945 | if (event_thread != NULL) | |
2946 | { | |
2947 | if (debug_threads) | |
2948 | debug_printf ("SEL: Select single-step %s\n", | |
2949 | target_pid_to_str (ptid_of (event_thread))); | |
2950 | } | |
2951 | } | |
2952 | if (event_thread == NULL) | |
2953 | { | |
2954 | /* No single-stepping LWP. Select one at random, out of those | |
2955 | which have had events. */ | |
2956 | ||
2957 | /* First see how many events we have. */ | |
2958 | find_inferior (&all_threads, count_events_callback, &num_events); | |
2959 | gdb_assert (num_events > 0); | |
2960 | ||
2961 | /* Now randomly pick a LWP out of those that have had | |
2962 | events. */ | |
2963 | random_selector = (int) | |
2964 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2965 | ||
2966 | if (debug_threads && num_events > 1) | |
2967 | debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n", | |
2968 | num_events, random_selector); | |
2969 | ||
2970 | event_thread | |
2971 | = (struct thread_info *) find_inferior (&all_threads, | |
2972 | select_event_lwp_callback, | |
2973 | &random_selector); | |
2974 | } | |
2975 | ||
2976 | if (event_thread != NULL) | |
2977 | { | |
2978 | struct lwp_info *event_lp = get_thread_lwp (event_thread); | |
2979 | ||
2980 | /* Switch the event LWP. */ | |
2981 | *orig_lp = event_lp; | |
2982 | } | |
2983 | } | |
2984 | ||
2985 | /* Decrement the suspend count of an LWP. */ | |
2986 | ||
2987 | static int | |
2988 | unsuspend_one_lwp (struct inferior_list_entry *entry, void *except) | |
2989 | { | |
2990 | struct thread_info *thread = (struct thread_info *) entry; | |
2991 | struct lwp_info *lwp = get_thread_lwp (thread); | |
2992 | ||
2993 | /* Ignore EXCEPT. */ | |
2994 | if (lwp == except) | |
2995 | return 0; | |
2996 | ||
2997 | lwp_suspended_decr (lwp); | |
2998 | return 0; | |
2999 | } | |
3000 | ||
3001 | /* Decrement the suspend count of all LWPs, except EXCEPT, if non | |
3002 | NULL. */ | |
3003 | ||
3004 | static void | |
3005 | unsuspend_all_lwps (struct lwp_info *except) | |
3006 | { | |
3007 | find_inferior (&all_threads, unsuspend_one_lwp, except); | |
3008 | } | |
3009 | ||
3010 | static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry); | |
3011 | static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry, | |
3012 | void *data); | |
3013 | static int lwp_running (struct inferior_list_entry *entry, void *data); | |
3014 | static ptid_t linux_wait_1 (ptid_t ptid, | |
3015 | struct target_waitstatus *ourstatus, | |
3016 | int target_options); | |
3017 | ||
3018 | /* Stabilize threads (move out of jump pads). | |
3019 | ||
3020 | If a thread is midway collecting a fast tracepoint, we need to | |
3021 | finish the collection and move it out of the jump pad before | |
3022 | reporting the signal. | |
3023 | ||
3024 | This avoids recursion while collecting (when a signal arrives | |
3025 | midway, and the signal handler itself collects), which would trash | |
3026 | the trace buffer. In case the user set a breakpoint in a signal | |
3027 | handler, this avoids the backtrace showing the jump pad, etc.. | |
3028 | Most importantly, there are certain things we can't do safely if | |
3029 | threads are stopped in a jump pad (or in its callee's). For | |
3030 | example: | |
3031 | ||
3032 | - starting a new trace run. A thread still collecting the | |
3033 | previous run, could trash the trace buffer when resumed. The trace | |
3034 | buffer control structures would have been reset but the thread had | |
3035 | no way to tell. The thread could even midway memcpy'ing to the | |
3036 | buffer, which would mean that when resumed, it would clobber the | |
3037 | trace buffer that had been set for a new run. | |
3038 | ||
3039 | - we can't rewrite/reuse the jump pads for new tracepoints | |
3040 | safely. Say you do tstart while a thread is stopped midway while | |
3041 | collecting. When the thread is later resumed, it finishes the | |
3042 | collection, and returns to the jump pad, to execute the original | |
3043 | instruction that was under the tracepoint jump at the time the | |
3044 | older run had been started. If the jump pad had been rewritten | |
3045 | since for something else in the new run, the thread would now | |
3046 | execute the wrong / random instructions. */ | |
3047 | ||
3048 | static void | |
3049 | linux_stabilize_threads (void) | |
3050 | { | |
3051 | struct thread_info *saved_thread; | |
3052 | struct thread_info *thread_stuck; | |
3053 | ||
3054 | thread_stuck | |
3055 | = (struct thread_info *) find_inferior (&all_threads, | |
3056 | stuck_in_jump_pad_callback, | |
3057 | NULL); | |
3058 | if (thread_stuck != NULL) | |
3059 | { | |
3060 | if (debug_threads) | |
3061 | debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n", | |
3062 | lwpid_of (thread_stuck)); | |
3063 | return; | |
3064 | } | |
3065 | ||
3066 | saved_thread = current_thread; | |
3067 | ||
3068 | stabilizing_threads = 1; | |
3069 | ||
3070 | /* Kick 'em all. */ | |
3071 | for_each_inferior (&all_threads, move_out_of_jump_pad_callback); | |
3072 | ||
3073 | /* Loop until all are stopped out of the jump pads. */ | |
3074 | while (find_inferior (&all_threads, lwp_running, NULL) != NULL) | |
3075 | { | |
3076 | struct target_waitstatus ourstatus; | |
3077 | struct lwp_info *lwp; | |
3078 | int wstat; | |
3079 | ||
3080 | /* Note that we go through the full wait even loop. While | |
3081 | moving threads out of jump pad, we need to be able to step | |
3082 | over internal breakpoints and such. */ | |
3083 | linux_wait_1 (minus_one_ptid, &ourstatus, 0); | |
3084 | ||
3085 | if (ourstatus.kind == TARGET_WAITKIND_STOPPED) | |
3086 | { | |
3087 | lwp = get_thread_lwp (current_thread); | |
3088 | ||
3089 | /* Lock it. */ | |
3090 | lwp_suspended_inc (lwp); | |
3091 | ||
3092 | if (ourstatus.value.sig != GDB_SIGNAL_0 | |
3093 | || current_thread->last_resume_kind == resume_stop) | |
3094 | { | |
3095 | wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig)); | |
3096 | enqueue_one_deferred_signal (lwp, &wstat); | |
3097 | } | |
3098 | } | |
3099 | } | |
3100 | ||
3101 | unsuspend_all_lwps (NULL); | |
3102 | ||
3103 | stabilizing_threads = 0; | |
3104 | ||
3105 | current_thread = saved_thread; | |
3106 | ||
3107 | if (debug_threads) | |
3108 | { | |
3109 | thread_stuck | |
3110 | = (struct thread_info *) find_inferior (&all_threads, | |
3111 | stuck_in_jump_pad_callback, | |
3112 | NULL); | |
3113 | if (thread_stuck != NULL) | |
3114 | debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n", | |
3115 | lwpid_of (thread_stuck)); | |
3116 | } | |
3117 | } | |
3118 | ||
3119 | /* Convenience function that is called when the kernel reports an | |
3120 | event that is not passed out to GDB. */ | |
3121 | ||
3122 | static ptid_t | |
3123 | ignore_event (struct target_waitstatus *ourstatus) | |
3124 | { | |
3125 | /* If we got an event, there may still be others, as a single | |
3126 | SIGCHLD can indicate more than one child stopped. This forces | |
3127 | another target_wait call. */ | |
3128 | async_file_mark (); | |
3129 | ||
3130 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3131 | return null_ptid; | |
3132 | } | |
3133 | ||
3134 | /* Convenience function that is called when the kernel reports an exit | |
3135 | event. This decides whether to report the event to GDB as a | |
3136 | process exit event, a thread exit event, or to suppress the | |
3137 | event. */ | |
3138 | ||
3139 | static ptid_t | |
3140 | filter_exit_event (struct lwp_info *event_child, | |
3141 | struct target_waitstatus *ourstatus) | |
3142 | { | |
3143 | struct thread_info *thread = get_lwp_thread (event_child); | |
3144 | ptid_t ptid = ptid_of (thread); | |
3145 | ||
3146 | if (!last_thread_of_process_p (pid_of (thread))) | |
3147 | { | |
3148 | if (report_thread_events) | |
3149 | ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED; | |
3150 | else | |
3151 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3152 | ||
3153 | delete_lwp (event_child); | |
3154 | } | |
3155 | return ptid; | |
3156 | } | |
3157 | ||
3158 | /* Returns 1 if GDB is interested in any event_child syscalls. */ | |
3159 | ||
3160 | static int | |
3161 | gdb_catching_syscalls_p (struct lwp_info *event_child) | |
3162 | { | |
3163 | struct thread_info *thread = get_lwp_thread (event_child); | |
3164 | struct process_info *proc = get_thread_process (thread); | |
3165 | ||
3166 | return !VEC_empty (int, proc->syscalls_to_catch); | |
3167 | } | |
3168 | ||
3169 | /* Returns 1 if GDB is interested in the event_child syscall. | |
3170 | Only to be called when stopped reason is SYSCALL_SIGTRAP. */ | |
3171 | ||
3172 | static int | |
3173 | gdb_catch_this_syscall_p (struct lwp_info *event_child) | |
3174 | { | |
3175 | int i, iter; | |
3176 | int sysno; | |
3177 | struct thread_info *thread = get_lwp_thread (event_child); | |
3178 | struct process_info *proc = get_thread_process (thread); | |
3179 | ||
3180 | if (VEC_empty (int, proc->syscalls_to_catch)) | |
3181 | return 0; | |
3182 | ||
3183 | if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL) | |
3184 | return 1; | |
3185 | ||
3186 | get_syscall_trapinfo (event_child, &sysno); | |
3187 | for (i = 0; | |
3188 | VEC_iterate (int, proc->syscalls_to_catch, i, iter); | |
3189 | i++) | |
3190 | if (iter == sysno) | |
3191 | return 1; | |
3192 | ||
3193 | return 0; | |
3194 | } | |
3195 | ||
3196 | /* Wait for process, returns status. */ | |
3197 | ||
3198 | static ptid_t | |
3199 | linux_wait_1 (ptid_t ptid, | |
3200 | struct target_waitstatus *ourstatus, int target_options) | |
3201 | { | |
3202 | int w; | |
3203 | struct lwp_info *event_child; | |
3204 | int options; | |
3205 | int pid; | |
3206 | int step_over_finished; | |
3207 | int bp_explains_trap; | |
3208 | int maybe_internal_trap; | |
3209 | int report_to_gdb; | |
3210 | int trace_event; | |
3211 | int in_step_range; | |
3212 | int any_resumed; | |
3213 | ||
3214 | if (debug_threads) | |
3215 | { | |
3216 | debug_enter (); | |
3217 | debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid)); | |
3218 | } | |
3219 | ||
3220 | /* Translate generic target options into linux options. */ | |
3221 | options = __WALL; | |
3222 | if (target_options & TARGET_WNOHANG) | |
3223 | options |= WNOHANG; | |
3224 | ||
3225 | bp_explains_trap = 0; | |
3226 | trace_event = 0; | |
3227 | in_step_range = 0; | |
3228 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3229 | ||
3230 | /* Find a resumed LWP, if any. */ | |
3231 | if (find_inferior (&all_threads, | |
3232 | status_pending_p_callback, | |
3233 | &minus_one_ptid) != NULL) | |
3234 | any_resumed = 1; | |
3235 | else if ((find_inferior (&all_threads, | |
3236 | not_stopped_callback, | |
3237 | &minus_one_ptid) != NULL)) | |
3238 | any_resumed = 1; | |
3239 | else | |
3240 | any_resumed = 0; | |
3241 | ||
3242 | if (ptid_equal (step_over_bkpt, null_ptid)) | |
3243 | pid = linux_wait_for_event (ptid, &w, options); | |
3244 | else | |
3245 | { | |
3246 | if (debug_threads) | |
3247 | debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n", | |
3248 | target_pid_to_str (step_over_bkpt)); | |
3249 | pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG); | |
3250 | } | |
3251 | ||
3252 | if (pid == 0 || (pid == -1 && !any_resumed)) | |
3253 | { | |
3254 | gdb_assert (target_options & TARGET_WNOHANG); | |
3255 | ||
3256 | if (debug_threads) | |
3257 | { | |
3258 | debug_printf ("linux_wait_1 ret = null_ptid, " | |
3259 | "TARGET_WAITKIND_IGNORE\n"); | |
3260 | debug_exit (); | |
3261 | } | |
3262 | ||
3263 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3264 | return null_ptid; | |
3265 | } | |
3266 | else if (pid == -1) | |
3267 | { | |
3268 | if (debug_threads) | |
3269 | { | |
3270 | debug_printf ("linux_wait_1 ret = null_ptid, " | |
3271 | "TARGET_WAITKIND_NO_RESUMED\n"); | |
3272 | debug_exit (); | |
3273 | } | |
3274 | ||
3275 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; | |
3276 | return null_ptid; | |
3277 | } | |
3278 | ||
3279 | event_child = get_thread_lwp (current_thread); | |
3280 | ||
3281 | /* linux_wait_for_event only returns an exit status for the last | |
3282 | child of a process. Report it. */ | |
3283 | if (WIFEXITED (w) || WIFSIGNALED (w)) | |
3284 | { | |
3285 | if (WIFEXITED (w)) | |
3286 | { | |
3287 | ourstatus->kind = TARGET_WAITKIND_EXITED; | |
3288 | ourstatus->value.integer = WEXITSTATUS (w); | |
3289 | ||
3290 | if (debug_threads) | |
3291 | { | |
3292 | debug_printf ("linux_wait_1 ret = %s, exited with " | |
3293 | "retcode %d\n", | |
3294 | target_pid_to_str (ptid_of (current_thread)), | |
3295 | WEXITSTATUS (w)); | |
3296 | debug_exit (); | |
3297 | } | |
3298 | } | |
3299 | else | |
3300 | { | |
3301 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
3302 | ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w)); | |
3303 | ||
3304 | if (debug_threads) | |
3305 | { | |
3306 | debug_printf ("linux_wait_1 ret = %s, terminated with " | |
3307 | "signal %d\n", | |
3308 | target_pid_to_str (ptid_of (current_thread)), | |
3309 | WTERMSIG (w)); | |
3310 | debug_exit (); | |
3311 | } | |
3312 | } | |
3313 | ||
3314 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) | |
3315 | return filter_exit_event (event_child, ourstatus); | |
3316 | ||
3317 | return ptid_of (current_thread); | |
3318 | } | |
3319 | ||
3320 | /* If step-over executes a breakpoint instruction, in the case of a | |
3321 | hardware single step it means a gdb/gdbserver breakpoint had been | |
3322 | planted on top of a permanent breakpoint, in the case of a software | |
3323 | single step it may just mean that gdbserver hit the reinsert breakpoint. | |
3324 | The PC has been adjusted by save_stop_reason to point at | |
3325 | the breakpoint address. | |
3326 | So in the case of the hardware single step advance the PC manually | |
3327 | past the breakpoint and in the case of software single step advance only | |
3328 | if it's not the reinsert_breakpoint we are hitting. | |
3329 | This avoids that a program would keep trapping a permanent breakpoint | |
3330 | forever. */ | |
3331 | if (!ptid_equal (step_over_bkpt, null_ptid) | |
3332 | && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3333 | && (event_child->stepping | |
3334 | || !reinsert_breakpoint_inserted_here (event_child->stop_pc))) | |
3335 | { | |
3336 | int increment_pc = 0; | |
3337 | int breakpoint_kind = 0; | |
3338 | CORE_ADDR stop_pc = event_child->stop_pc; | |
3339 | ||
3340 | breakpoint_kind = | |
3341 | the_target->breakpoint_kind_from_current_state (&stop_pc); | |
3342 | the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc); | |
3343 | ||
3344 | if (debug_threads) | |
3345 | { | |
3346 | debug_printf ("step-over for %s executed software breakpoint\n", | |
3347 | target_pid_to_str (ptid_of (current_thread))); | |
3348 | } | |
3349 | ||
3350 | if (increment_pc != 0) | |
3351 | { | |
3352 | struct regcache *regcache | |
3353 | = get_thread_regcache (current_thread, 1); | |
3354 | ||
3355 | event_child->stop_pc += increment_pc; | |
3356 | (*the_low_target.set_pc) (regcache, event_child->stop_pc); | |
3357 | ||
3358 | if (!(*the_low_target.breakpoint_at) (event_child->stop_pc)) | |
3359 | event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
3360 | } | |
3361 | } | |
3362 | ||
3363 | /* If this event was not handled before, and is not a SIGTRAP, we | |
3364 | report it. SIGILL and SIGSEGV are also treated as traps in case | |
3365 | a breakpoint is inserted at the current PC. If this target does | |
3366 | not support internal breakpoints at all, we also report the | |
3367 | SIGTRAP without further processing; it's of no concern to us. */ | |
3368 | maybe_internal_trap | |
3369 | = (supports_breakpoints () | |
3370 | && (WSTOPSIG (w) == SIGTRAP | |
3371 | || ((WSTOPSIG (w) == SIGILL | |
3372 | || WSTOPSIG (w) == SIGSEGV) | |
3373 | && (*the_low_target.breakpoint_at) (event_child->stop_pc)))); | |
3374 | ||
3375 | if (maybe_internal_trap) | |
3376 | { | |
3377 | /* Handle anything that requires bookkeeping before deciding to | |
3378 | report the event or continue waiting. */ | |
3379 | ||
3380 | /* First check if we can explain the SIGTRAP with an internal | |
3381 | breakpoint, or if we should possibly report the event to GDB. | |
3382 | Do this before anything that may remove or insert a | |
3383 | breakpoint. */ | |
3384 | bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc); | |
3385 | ||
3386 | /* We have a SIGTRAP, possibly a step-over dance has just | |
3387 | finished. If so, tweak the state machine accordingly, | |
3388 | reinsert breakpoints and delete any reinsert (software | |
3389 | single-step) breakpoints. */ | |
3390 | step_over_finished = finish_step_over (event_child); | |
3391 | ||
3392 | /* Now invoke the callbacks of any internal breakpoints there. */ | |
3393 | check_breakpoints (event_child->stop_pc); | |
3394 | ||
3395 | /* Handle tracepoint data collecting. This may overflow the | |
3396 | trace buffer, and cause a tracing stop, removing | |
3397 | breakpoints. */ | |
3398 | trace_event = handle_tracepoints (event_child); | |
3399 | ||
3400 | if (bp_explains_trap) | |
3401 | { | |
3402 | if (debug_threads) | |
3403 | debug_printf ("Hit a gdbserver breakpoint.\n"); | |
3404 | } | |
3405 | } | |
3406 | else | |
3407 | { | |
3408 | /* We have some other signal, possibly a step-over dance was in | |
3409 | progress, and it should be cancelled too. */ | |
3410 | step_over_finished = finish_step_over (event_child); | |
3411 | } | |
3412 | ||
3413 | /* We have all the data we need. Either report the event to GDB, or | |
3414 | resume threads and keep waiting for more. */ | |
3415 | ||
3416 | /* If we're collecting a fast tracepoint, finish the collection and | |
3417 | move out of the jump pad before delivering a signal. See | |
3418 | linux_stabilize_threads. */ | |
3419 | ||
3420 | if (WIFSTOPPED (w) | |
3421 | && WSTOPSIG (w) != SIGTRAP | |
3422 | && supports_fast_tracepoints () | |
3423 | && agent_loaded_p ()) | |
3424 | { | |
3425 | if (debug_threads) | |
3426 | debug_printf ("Got signal %d for LWP %ld. Check if we need " | |
3427 | "to defer or adjust it.\n", | |
3428 | WSTOPSIG (w), lwpid_of (current_thread)); | |
3429 | ||
3430 | /* Allow debugging the jump pad itself. */ | |
3431 | if (current_thread->last_resume_kind != resume_step | |
3432 | && maybe_move_out_of_jump_pad (event_child, &w)) | |
3433 | { | |
3434 | enqueue_one_deferred_signal (event_child, &w); | |
3435 | ||
3436 | if (debug_threads) | |
3437 | debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n", | |
3438 | WSTOPSIG (w), lwpid_of (current_thread)); | |
3439 | ||
3440 | linux_resume_one_lwp (event_child, 0, 0, NULL); | |
3441 | ||
3442 | return ignore_event (ourstatus); | |
3443 | } | |
3444 | } | |
3445 | ||
3446 | if (event_child->collecting_fast_tracepoint) | |
3447 | { | |
3448 | if (debug_threads) | |
3449 | debug_printf ("LWP %ld was trying to move out of the jump pad (%d). " | |
3450 | "Check if we're already there.\n", | |
3451 | lwpid_of (current_thread), | |
3452 | event_child->collecting_fast_tracepoint); | |
3453 | ||
3454 | trace_event = 1; | |
3455 | ||
3456 | event_child->collecting_fast_tracepoint | |
3457 | = linux_fast_tracepoint_collecting (event_child, NULL); | |
3458 | ||
3459 | if (event_child->collecting_fast_tracepoint != 1) | |
3460 | { | |
3461 | /* No longer need this breakpoint. */ | |
3462 | if (event_child->exit_jump_pad_bkpt != NULL) | |
3463 | { | |
3464 | if (debug_threads) | |
3465 | debug_printf ("No longer need exit-jump-pad bkpt; removing it." | |
3466 | "stopping all threads momentarily.\n"); | |
3467 | ||
3468 | /* Other running threads could hit this breakpoint. | |
3469 | We don't handle moribund locations like GDB does, | |
3470 | instead we always pause all threads when removing | |
3471 | breakpoints, so that any step-over or | |
3472 | decr_pc_after_break adjustment is always taken | |
3473 | care of while the breakpoint is still | |
3474 | inserted. */ | |
3475 | stop_all_lwps (1, event_child); | |
3476 | ||
3477 | delete_breakpoint (event_child->exit_jump_pad_bkpt); | |
3478 | event_child->exit_jump_pad_bkpt = NULL; | |
3479 | ||
3480 | unstop_all_lwps (1, event_child); | |
3481 | ||
3482 | gdb_assert (event_child->suspended >= 0); | |
3483 | } | |
3484 | } | |
3485 | ||
3486 | if (event_child->collecting_fast_tracepoint == 0) | |
3487 | { | |
3488 | if (debug_threads) | |
3489 | debug_printf ("fast tracepoint finished " | |
3490 | "collecting successfully.\n"); | |
3491 | ||
3492 | /* We may have a deferred signal to report. */ | |
3493 | if (dequeue_one_deferred_signal (event_child, &w)) | |
3494 | { | |
3495 | if (debug_threads) | |
3496 | debug_printf ("dequeued one signal.\n"); | |
3497 | } | |
3498 | else | |
3499 | { | |
3500 | if (debug_threads) | |
3501 | debug_printf ("no deferred signals.\n"); | |
3502 | ||
3503 | if (stabilizing_threads) | |
3504 | { | |
3505 | ourstatus->kind = TARGET_WAITKIND_STOPPED; | |
3506 | ourstatus->value.sig = GDB_SIGNAL_0; | |
3507 | ||
3508 | if (debug_threads) | |
3509 | { | |
3510 | debug_printf ("linux_wait_1 ret = %s, stopped " | |
3511 | "while stabilizing threads\n", | |
3512 | target_pid_to_str (ptid_of (current_thread))); | |
3513 | debug_exit (); | |
3514 | } | |
3515 | ||
3516 | return ptid_of (current_thread); | |
3517 | } | |
3518 | } | |
3519 | } | |
3520 | } | |
3521 | ||
3522 | /* Check whether GDB would be interested in this event. */ | |
3523 | ||
3524 | /* Check if GDB is interested in this syscall. */ | |
3525 | if (WIFSTOPPED (w) | |
3526 | && WSTOPSIG (w) == SYSCALL_SIGTRAP | |
3527 | && !gdb_catch_this_syscall_p (event_child)) | |
3528 | { | |
3529 | if (debug_threads) | |
3530 | { | |
3531 | debug_printf ("Ignored syscall for LWP %ld.\n", | |
3532 | lwpid_of (current_thread)); | |
3533 | } | |
3534 | ||
3535 | linux_resume_one_lwp (event_child, event_child->stepping, | |
3536 | 0, NULL); | |
3537 | return ignore_event (ourstatus); | |
3538 | } | |
3539 | ||
3540 | /* If GDB is not interested in this signal, don't stop other | |
3541 | threads, and don't report it to GDB. Just resume the inferior | |
3542 | right away. We do this for threading-related signals as well as | |
3543 | any that GDB specifically requested we ignore. But never ignore | |
3544 | SIGSTOP if we sent it ourselves, and do not ignore signals when | |
3545 | stepping - they may require special handling to skip the signal | |
3546 | handler. Also never ignore signals that could be caused by a | |
3547 | breakpoint. */ | |
3548 | if (WIFSTOPPED (w) | |
3549 | && current_thread->last_resume_kind != resume_step | |
3550 | && ( | |
3551 | #if defined (USE_THREAD_DB) && !defined (__ANDROID__) | |
3552 | (current_process ()->priv->thread_db != NULL | |
3553 | && (WSTOPSIG (w) == __SIGRTMIN | |
3554 | || WSTOPSIG (w) == __SIGRTMIN + 1)) | |
3555 | || | |
3556 | #endif | |
3557 | (pass_signals[gdb_signal_from_host (WSTOPSIG (w))] | |
3558 | && !(WSTOPSIG (w) == SIGSTOP | |
3559 | && current_thread->last_resume_kind == resume_stop) | |
3560 | && !linux_wstatus_maybe_breakpoint (w)))) | |
3561 | { | |
3562 | siginfo_t info, *info_p; | |
3563 | ||
3564 | if (debug_threads) | |
3565 | debug_printf ("Ignored signal %d for LWP %ld.\n", | |
3566 | WSTOPSIG (w), lwpid_of (current_thread)); | |
3567 | ||
3568 | if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread), | |
3569 | (PTRACE_TYPE_ARG3) 0, &info) == 0) | |
3570 | info_p = &info; | |
3571 | else | |
3572 | info_p = NULL; | |
3573 | ||
3574 | if (step_over_finished) | |
3575 | { | |
3576 | /* We cancelled this thread's step-over above. We still | |
3577 | need to unsuspend all other LWPs, and set them back | |
3578 | running again while the signal handler runs. */ | |
3579 | unsuspend_all_lwps (event_child); | |
3580 | ||
3581 | /* Enqueue the pending signal info so that proceed_all_lwps | |
3582 | doesn't lose it. */ | |
3583 | enqueue_pending_signal (event_child, WSTOPSIG (w), info_p); | |
3584 | ||
3585 | proceed_all_lwps (); | |
3586 | } | |
3587 | else | |
3588 | { | |
3589 | linux_resume_one_lwp (event_child, event_child->stepping, | |
3590 | WSTOPSIG (w), info_p); | |
3591 | } | |
3592 | return ignore_event (ourstatus); | |
3593 | } | |
3594 | ||
3595 | /* Note that all addresses are always "out of the step range" when | |
3596 | there's no range to begin with. */ | |
3597 | in_step_range = lwp_in_step_range (event_child); | |
3598 | ||
3599 | /* If GDB wanted this thread to single step, and the thread is out | |
3600 | of the step range, we always want to report the SIGTRAP, and let | |
3601 | GDB handle it. Watchpoints should always be reported. So should | |
3602 | signals we can't explain. A SIGTRAP we can't explain could be a | |
3603 | GDB breakpoint --- we may or not support Z0 breakpoints. If we | |
3604 | do, we're be able to handle GDB breakpoints on top of internal | |
3605 | breakpoints, by handling the internal breakpoint and still | |
3606 | reporting the event to GDB. If we don't, we're out of luck, GDB | |
3607 | won't see the breakpoint hit. If we see a single-step event but | |
3608 | the thread should be continuing, don't pass the trap to gdb. | |
3609 | That indicates that we had previously finished a single-step but | |
3610 | left the single-step pending -- see | |
3611 | complete_ongoing_step_over. */ | |
3612 | report_to_gdb = (!maybe_internal_trap | |
3613 | || (current_thread->last_resume_kind == resume_step | |
3614 | && !in_step_range) | |
3615 | || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT | |
3616 | || (!in_step_range | |
3617 | && !bp_explains_trap | |
3618 | && !trace_event | |
3619 | && !step_over_finished | |
3620 | && !(current_thread->last_resume_kind == resume_continue | |
3621 | && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)) | |
3622 | || (gdb_breakpoint_here (event_child->stop_pc) | |
3623 | && gdb_condition_true_at_breakpoint (event_child->stop_pc) | |
3624 | && gdb_no_commands_at_breakpoint (event_child->stop_pc)) | |
3625 | || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE); | |
3626 | ||
3627 | run_breakpoint_commands (event_child->stop_pc); | |
3628 | ||
3629 | /* We found no reason GDB would want us to stop. We either hit one | |
3630 | of our own breakpoints, or finished an internal step GDB | |
3631 | shouldn't know about. */ | |
3632 | if (!report_to_gdb) | |
3633 | { | |
3634 | if (debug_threads) | |
3635 | { | |
3636 | if (bp_explains_trap) | |
3637 | debug_printf ("Hit a gdbserver breakpoint.\n"); | |
3638 | if (step_over_finished) | |
3639 | debug_printf ("Step-over finished.\n"); | |
3640 | if (trace_event) | |
3641 | debug_printf ("Tracepoint event.\n"); | |
3642 | if (lwp_in_step_range (event_child)) | |
3643 | debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n", | |
3644 | paddress (event_child->stop_pc), | |
3645 | paddress (event_child->step_range_start), | |
3646 | paddress (event_child->step_range_end)); | |
3647 | } | |
3648 | ||
3649 | /* We're not reporting this breakpoint to GDB, so apply the | |
3650 | decr_pc_after_break adjustment to the inferior's regcache | |
3651 | ourselves. */ | |
3652 | ||
3653 | if (the_low_target.set_pc != NULL) | |
3654 | { | |
3655 | struct regcache *regcache | |
3656 | = get_thread_regcache (current_thread, 1); | |
3657 | (*the_low_target.set_pc) (regcache, event_child->stop_pc); | |
3658 | } | |
3659 | ||
3660 | /* We may have finished stepping over a breakpoint. If so, | |
3661 | we've stopped and suspended all LWPs momentarily except the | |
3662 | stepping one. This is where we resume them all again. We're | |
3663 | going to keep waiting, so use proceed, which handles stepping | |
3664 | over the next breakpoint. */ | |
3665 | if (debug_threads) | |
3666 | debug_printf ("proceeding all threads.\n"); | |
3667 | ||
3668 | if (step_over_finished) | |
3669 | unsuspend_all_lwps (event_child); | |
3670 | ||
3671 | proceed_all_lwps (); | |
3672 | return ignore_event (ourstatus); | |
3673 | } | |
3674 | ||
3675 | if (debug_threads) | |
3676 | { | |
3677 | if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3678 | { | |
3679 | char *str; | |
3680 | ||
3681 | str = target_waitstatus_to_string (&event_child->waitstatus); | |
3682 | debug_printf ("LWP %ld: extended event with waitstatus %s\n", | |
3683 | lwpid_of (get_lwp_thread (event_child)), str); | |
3684 | xfree (str); | |
3685 | } | |
3686 | if (current_thread->last_resume_kind == resume_step) | |
3687 | { | |
3688 | if (event_child->step_range_start == event_child->step_range_end) | |
3689 | debug_printf ("GDB wanted to single-step, reporting event.\n"); | |
3690 | else if (!lwp_in_step_range (event_child)) | |
3691 | debug_printf ("Out of step range, reporting event.\n"); | |
3692 | } | |
3693 | if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT) | |
3694 | debug_printf ("Stopped by watchpoint.\n"); | |
3695 | else if (gdb_breakpoint_here (event_child->stop_pc)) | |
3696 | debug_printf ("Stopped by GDB breakpoint.\n"); | |
3697 | if (debug_threads) | |
3698 | debug_printf ("Hit a non-gdbserver trap event.\n"); | |
3699 | } | |
3700 | ||
3701 | /* Alright, we're going to report a stop. */ | |
3702 | ||
3703 | if (!stabilizing_threads) | |
3704 | { | |
3705 | /* In all-stop, stop all threads. */ | |
3706 | if (!non_stop) | |
3707 | stop_all_lwps (0, NULL); | |
3708 | ||
3709 | /* If we're not waiting for a specific LWP, choose an event LWP | |
3710 | from among those that have had events. Giving equal priority | |
3711 | to all LWPs that have had events helps prevent | |
3712 | starvation. */ | |
3713 | if (ptid_equal (ptid, minus_one_ptid)) | |
3714 | { | |
3715 | event_child->status_pending_p = 1; | |
3716 | event_child->status_pending = w; | |
3717 | ||
3718 | select_event_lwp (&event_child); | |
3719 | ||
3720 | /* current_thread and event_child must stay in sync. */ | |
3721 | current_thread = get_lwp_thread (event_child); | |
3722 | ||
3723 | event_child->status_pending_p = 0; | |
3724 | w = event_child->status_pending; | |
3725 | } | |
3726 | ||
3727 | if (step_over_finished) | |
3728 | { | |
3729 | if (!non_stop) | |
3730 | { | |
3731 | /* If we were doing a step-over, all other threads but | |
3732 | the stepping one had been paused in start_step_over, | |
3733 | with their suspend counts incremented. We don't want | |
3734 | to do a full unstop/unpause, because we're in | |
3735 | all-stop mode (so we want threads stopped), but we | |
3736 | still need to unsuspend the other threads, to | |
3737 | decrement their `suspended' count back. */ | |
3738 | unsuspend_all_lwps (event_child); | |
3739 | } | |
3740 | else | |
3741 | { | |
3742 | /* If we just finished a step-over, then all threads had | |
3743 | been momentarily paused. In all-stop, that's fine, | |
3744 | we want threads stopped by now anyway. In non-stop, | |
3745 | we need to re-resume threads that GDB wanted to be | |
3746 | running. */ | |
3747 | unstop_all_lwps (1, event_child); | |
3748 | } | |
3749 | } | |
3750 | ||
3751 | /* Stabilize threads (move out of jump pads). */ | |
3752 | if (!non_stop) | |
3753 | stabilize_threads (); | |
3754 | } | |
3755 | else | |
3756 | { | |
3757 | /* If we just finished a step-over, then all threads had been | |
3758 | momentarily paused. In all-stop, that's fine, we want | |
3759 | threads stopped by now anyway. In non-stop, we need to | |
3760 | re-resume threads that GDB wanted to be running. */ | |
3761 | if (step_over_finished) | |
3762 | unstop_all_lwps (1, event_child); | |
3763 | } | |
3764 | ||
3765 | if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3766 | { | |
3767 | /* If the reported event is an exit, fork, vfork or exec, let | |
3768 | GDB know. */ | |
3769 | *ourstatus = event_child->waitstatus; | |
3770 | /* Clear the event lwp's waitstatus since we handled it already. */ | |
3771 | event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3772 | } | |
3773 | else | |
3774 | ourstatus->kind = TARGET_WAITKIND_STOPPED; | |
3775 | ||
3776 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
3777 | it was a software breakpoint, and the client doesn't know we can | |
3778 | adjust the breakpoint ourselves. */ | |
3779 | if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3780 | && !swbreak_feature) | |
3781 | { | |
3782 | int decr_pc = the_low_target.decr_pc_after_break; | |
3783 | ||
3784 | if (decr_pc != 0) | |
3785 | { | |
3786 | struct regcache *regcache | |
3787 | = get_thread_regcache (current_thread, 1); | |
3788 | (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc); | |
3789 | } | |
3790 | } | |
3791 | ||
3792 | if (WSTOPSIG (w) == SYSCALL_SIGTRAP) | |
3793 | { | |
3794 | get_syscall_trapinfo (event_child, | |
3795 | &ourstatus->value.syscall_number); | |
3796 | ourstatus->kind = event_child->syscall_state; | |
3797 | } | |
3798 | else if (current_thread->last_resume_kind == resume_stop | |
3799 | && WSTOPSIG (w) == SIGSTOP) | |
3800 | { | |
3801 | /* A thread that has been requested to stop by GDB with vCont;t, | |
3802 | and it stopped cleanly, so report as SIG0. The use of | |
3803 | SIGSTOP is an implementation detail. */ | |
3804 | ourstatus->value.sig = GDB_SIGNAL_0; | |
3805 | } | |
3806 | else if (current_thread->last_resume_kind == resume_stop | |
3807 | && WSTOPSIG (w) != SIGSTOP) | |
3808 | { | |
3809 | /* A thread that has been requested to stop by GDB with vCont;t, | |
3810 | but, it stopped for other reasons. */ | |
3811 | ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w)); | |
3812 | } | |
3813 | else if (ourstatus->kind == TARGET_WAITKIND_STOPPED) | |
3814 | { | |
3815 | ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w)); | |
3816 | } | |
3817 | ||
3818 | gdb_assert (ptid_equal (step_over_bkpt, null_ptid)); | |
3819 | ||
3820 | if (debug_threads) | |
3821 | { | |
3822 | debug_printf ("linux_wait_1 ret = %s, %d, %d\n", | |
3823 | target_pid_to_str (ptid_of (current_thread)), | |
3824 | ourstatus->kind, ourstatus->value.sig); | |
3825 | debug_exit (); | |
3826 | } | |
3827 | ||
3828 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) | |
3829 | return filter_exit_event (event_child, ourstatus); | |
3830 | ||
3831 | return ptid_of (current_thread); | |
3832 | } | |
3833 | ||
3834 | /* Get rid of any pending event in the pipe. */ | |
3835 | static void | |
3836 | async_file_flush (void) | |
3837 | { | |
3838 | int ret; | |
3839 | char buf; | |
3840 | ||
3841 | do | |
3842 | ret = read (linux_event_pipe[0], &buf, 1); | |
3843 | while (ret >= 0 || (ret == -1 && errno == EINTR)); | |
3844 | } | |
3845 | ||
3846 | /* Put something in the pipe, so the event loop wakes up. */ | |
3847 | static void | |
3848 | async_file_mark (void) | |
3849 | { | |
3850 | int ret; | |
3851 | ||
3852 | async_file_flush (); | |
3853 | ||
3854 | do | |
3855 | ret = write (linux_event_pipe[1], "+", 1); | |
3856 | while (ret == 0 || (ret == -1 && errno == EINTR)); | |
3857 | ||
3858 | /* Ignore EAGAIN. If the pipe is full, the event loop will already | |
3859 | be awakened anyway. */ | |
3860 | } | |
3861 | ||
3862 | static ptid_t | |
3863 | linux_wait (ptid_t ptid, | |
3864 | struct target_waitstatus *ourstatus, int target_options) | |
3865 | { | |
3866 | ptid_t event_ptid; | |
3867 | ||
3868 | /* Flush the async file first. */ | |
3869 | if (target_is_async_p ()) | |
3870 | async_file_flush (); | |
3871 | ||
3872 | do | |
3873 | { | |
3874 | event_ptid = linux_wait_1 (ptid, ourstatus, target_options); | |
3875 | } | |
3876 | while ((target_options & TARGET_WNOHANG) == 0 | |
3877 | && ptid_equal (event_ptid, null_ptid) | |
3878 | && ourstatus->kind == TARGET_WAITKIND_IGNORE); | |
3879 | ||
3880 | /* If at least one stop was reported, there may be more. A single | |
3881 | SIGCHLD can signal more than one child stop. */ | |
3882 | if (target_is_async_p () | |
3883 | && (target_options & TARGET_WNOHANG) != 0 | |
3884 | && !ptid_equal (event_ptid, null_ptid)) | |
3885 | async_file_mark (); | |
3886 | ||
3887 | return event_ptid; | |
3888 | } | |
3889 | ||
3890 | /* Send a signal to an LWP. */ | |
3891 | ||
3892 | static int | |
3893 | kill_lwp (unsigned long lwpid, int signo) | |
3894 | { | |
3895 | int ret; | |
3896 | ||
3897 | errno = 0; | |
3898 | ret = syscall (__NR_tkill, lwpid, signo); | |
3899 | if (errno == ENOSYS) | |
3900 | { | |
3901 | /* If tkill fails, then we are not using nptl threads, a | |
3902 | configuration we no longer support. */ | |
3903 | perror_with_name (("tkill")); | |
3904 | } | |
3905 | return ret; | |
3906 | } | |
3907 | ||
3908 | void | |
3909 | linux_stop_lwp (struct lwp_info *lwp) | |
3910 | { | |
3911 | send_sigstop (lwp); | |
3912 | } | |
3913 | ||
3914 | static void | |
3915 | send_sigstop (struct lwp_info *lwp) | |
3916 | { | |
3917 | int pid; | |
3918 | ||
3919 | pid = lwpid_of (get_lwp_thread (lwp)); | |
3920 | ||
3921 | /* If we already have a pending stop signal for this process, don't | |
3922 | send another. */ | |
3923 | if (lwp->stop_expected) | |
3924 | { | |
3925 | if (debug_threads) | |
3926 | debug_printf ("Have pending sigstop for lwp %d\n", pid); | |
3927 | ||
3928 | return; | |
3929 | } | |
3930 | ||
3931 | if (debug_threads) | |
3932 | debug_printf ("Sending sigstop to lwp %d\n", pid); | |
3933 | ||
3934 | lwp->stop_expected = 1; | |
3935 | kill_lwp (pid, SIGSTOP); | |
3936 | } | |
3937 | ||
3938 | static int | |
3939 | send_sigstop_callback (struct inferior_list_entry *entry, void *except) | |
3940 | { | |
3941 | struct thread_info *thread = (struct thread_info *) entry; | |
3942 | struct lwp_info *lwp = get_thread_lwp (thread); | |
3943 | ||
3944 | /* Ignore EXCEPT. */ | |
3945 | if (lwp == except) | |
3946 | return 0; | |
3947 | ||
3948 | if (lwp->stopped) | |
3949 | return 0; | |
3950 | ||
3951 | send_sigstop (lwp); | |
3952 | return 0; | |
3953 | } | |
3954 | ||
3955 | /* Increment the suspend count of an LWP, and stop it, if not stopped | |
3956 | yet. */ | |
3957 | static int | |
3958 | suspend_and_send_sigstop_callback (struct inferior_list_entry *entry, | |
3959 | void *except) | |
3960 | { | |
3961 | struct thread_info *thread = (struct thread_info *) entry; | |
3962 | struct lwp_info *lwp = get_thread_lwp (thread); | |
3963 | ||
3964 | /* Ignore EXCEPT. */ | |
3965 | if (lwp == except) | |
3966 | return 0; | |
3967 | ||
3968 | lwp_suspended_inc (lwp); | |
3969 | ||
3970 | return send_sigstop_callback (entry, except); | |
3971 | } | |
3972 | ||
3973 | static void | |
3974 | mark_lwp_dead (struct lwp_info *lwp, int wstat) | |
3975 | { | |
3976 | /* Store the exit status for later. */ | |
3977 | lwp->status_pending_p = 1; | |
3978 | lwp->status_pending = wstat; | |
3979 | ||
3980 | /* Store in waitstatus as well, as there's nothing else to process | |
3981 | for this event. */ | |
3982 | if (WIFEXITED (wstat)) | |
3983 | { | |
3984 | lwp->waitstatus.kind = TARGET_WAITKIND_EXITED; | |
3985 | lwp->waitstatus.value.integer = WEXITSTATUS (wstat); | |
3986 | } | |
3987 | else if (WIFSIGNALED (wstat)) | |
3988 | { | |
3989 | lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED; | |
3990 | lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat)); | |
3991 | } | |
3992 | ||
3993 | /* Prevent trying to stop it. */ | |
3994 | lwp->stopped = 1; | |
3995 | ||
3996 | /* No further stops are expected from a dead lwp. */ | |
3997 | lwp->stop_expected = 0; | |
3998 | } | |
3999 | ||
4000 | /* Return true if LWP has exited already, and has a pending exit event | |
4001 | to report to GDB. */ | |
4002 | ||
4003 | static int | |
4004 | lwp_is_marked_dead (struct lwp_info *lwp) | |
4005 | { | |
4006 | return (lwp->status_pending_p | |
4007 | && (WIFEXITED (lwp->status_pending) | |
4008 | || WIFSIGNALED (lwp->status_pending))); | |
4009 | } | |
4010 | ||
4011 | /* Wait for all children to stop for the SIGSTOPs we just queued. */ | |
4012 | ||
4013 | static void | |
4014 | wait_for_sigstop (void) | |
4015 | { | |
4016 | struct thread_info *saved_thread; | |
4017 | ptid_t saved_tid; | |
4018 | int wstat; | |
4019 | int ret; | |
4020 | ||
4021 | saved_thread = current_thread; | |
4022 | if (saved_thread != NULL) | |
4023 | saved_tid = saved_thread->entry.id; | |
4024 | else | |
4025 | saved_tid = null_ptid; /* avoid bogus unused warning */ | |
4026 | ||
4027 | if (debug_threads) | |
4028 | debug_printf ("wait_for_sigstop: pulling events\n"); | |
4029 | ||
4030 | /* Passing NULL_PTID as filter indicates we want all events to be | |
4031 | left pending. Eventually this returns when there are no | |
4032 | unwaited-for children left. */ | |
4033 | ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid, | |
4034 | &wstat, __WALL); | |
4035 | gdb_assert (ret == -1); | |
4036 | ||
4037 | if (saved_thread == NULL || linux_thread_alive (saved_tid)) | |
4038 | current_thread = saved_thread; | |
4039 | else | |
4040 | { | |
4041 | if (debug_threads) | |
4042 | debug_printf ("Previously current thread died.\n"); | |
4043 | ||
4044 | /* We can't change the current inferior behind GDB's back, | |
4045 | otherwise, a subsequent command may apply to the wrong | |
4046 | process. */ | |
4047 | current_thread = NULL; | |
4048 | } | |
4049 | } | |
4050 | ||
4051 | /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't | |
4052 | move it out, because we need to report the stop event to GDB. For | |
4053 | example, if the user puts a breakpoint in the jump pad, it's | |
4054 | because she wants to debug it. */ | |
4055 | ||
4056 | static int | |
4057 | stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data) | |
4058 | { | |
4059 | struct thread_info *thread = (struct thread_info *) entry; | |
4060 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4061 | ||
4062 | if (lwp->suspended != 0) | |
4063 | { | |
4064 | internal_error (__FILE__, __LINE__, | |
4065 | "LWP %ld is suspended, suspended=%d\n", | |
4066 | lwpid_of (thread), lwp->suspended); | |
4067 | } | |
4068 | gdb_assert (lwp->stopped); | |
4069 | ||
4070 | /* Allow debugging the jump pad, gdb_collect, etc.. */ | |
4071 | return (supports_fast_tracepoints () | |
4072 | && agent_loaded_p () | |
4073 | && (gdb_breakpoint_here (lwp->stop_pc) | |
4074 | || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT | |
4075 | || thread->last_resume_kind == resume_step) | |
4076 | && linux_fast_tracepoint_collecting (lwp, NULL)); | |
4077 | } | |
4078 | ||
4079 | static void | |
4080 | move_out_of_jump_pad_callback (struct inferior_list_entry *entry) | |
4081 | { | |
4082 | struct thread_info *thread = (struct thread_info *) entry; | |
4083 | struct thread_info *saved_thread; | |
4084 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4085 | int *wstat; | |
4086 | ||
4087 | if (lwp->suspended != 0) | |
4088 | { | |
4089 | internal_error (__FILE__, __LINE__, | |
4090 | "LWP %ld is suspended, suspended=%d\n", | |
4091 | lwpid_of (thread), lwp->suspended); | |
4092 | } | |
4093 | gdb_assert (lwp->stopped); | |
4094 | ||
4095 | /* For gdb_breakpoint_here. */ | |
4096 | saved_thread = current_thread; | |
4097 | current_thread = thread; | |
4098 | ||
4099 | wstat = lwp->status_pending_p ? &lwp->status_pending : NULL; | |
4100 | ||
4101 | /* Allow debugging the jump pad, gdb_collect, etc. */ | |
4102 | if (!gdb_breakpoint_here (lwp->stop_pc) | |
4103 | && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT | |
4104 | && thread->last_resume_kind != resume_step | |
4105 | && maybe_move_out_of_jump_pad (lwp, wstat)) | |
4106 | { | |
4107 | if (debug_threads) | |
4108 | debug_printf ("LWP %ld needs stabilizing (in jump pad)\n", | |
4109 | lwpid_of (thread)); | |
4110 | ||
4111 | if (wstat) | |
4112 | { | |
4113 | lwp->status_pending_p = 0; | |
4114 | enqueue_one_deferred_signal (lwp, wstat); | |
4115 | ||
4116 | if (debug_threads) | |
4117 | debug_printf ("Signal %d for LWP %ld deferred " | |
4118 | "(in jump pad)\n", | |
4119 | WSTOPSIG (*wstat), lwpid_of (thread)); | |
4120 | } | |
4121 | ||
4122 | linux_resume_one_lwp (lwp, 0, 0, NULL); | |
4123 | } | |
4124 | else | |
4125 | lwp_suspended_inc (lwp); | |
4126 | ||
4127 | current_thread = saved_thread; | |
4128 | } | |
4129 | ||
4130 | static int | |
4131 | lwp_running (struct inferior_list_entry *entry, void *data) | |
4132 | { | |
4133 | struct thread_info *thread = (struct thread_info *) entry; | |
4134 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4135 | ||
4136 | if (lwp_is_marked_dead (lwp)) | |
4137 | return 0; | |
4138 | if (lwp->stopped) | |
4139 | return 0; | |
4140 | return 1; | |
4141 | } | |
4142 | ||
4143 | /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL. | |
4144 | If SUSPEND, then also increase the suspend count of every LWP, | |
4145 | except EXCEPT. */ | |
4146 | ||
4147 | static void | |
4148 | stop_all_lwps (int suspend, struct lwp_info *except) | |
4149 | { | |
4150 | /* Should not be called recursively. */ | |
4151 | gdb_assert (stopping_threads == NOT_STOPPING_THREADS); | |
4152 | ||
4153 | if (debug_threads) | |
4154 | { | |
4155 | debug_enter (); | |
4156 | debug_printf ("stop_all_lwps (%s, except=%s)\n", | |
4157 | suspend ? "stop-and-suspend" : "stop", | |
4158 | except != NULL | |
4159 | ? target_pid_to_str (ptid_of (get_lwp_thread (except))) | |
4160 | : "none"); | |
4161 | } | |
4162 | ||
4163 | stopping_threads = (suspend | |
4164 | ? STOPPING_AND_SUSPENDING_THREADS | |
4165 | : STOPPING_THREADS); | |
4166 | ||
4167 | if (suspend) | |
4168 | find_inferior (&all_threads, suspend_and_send_sigstop_callback, except); | |
4169 | else | |
4170 | find_inferior (&all_threads, send_sigstop_callback, except); | |
4171 | wait_for_sigstop (); | |
4172 | stopping_threads = NOT_STOPPING_THREADS; | |
4173 | ||
4174 | if (debug_threads) | |
4175 | { | |
4176 | debug_printf ("stop_all_lwps done, setting stopping_threads " | |
4177 | "back to !stopping\n"); | |
4178 | debug_exit (); | |
4179 | } | |
4180 | } | |
4181 | ||
4182 | /* Enqueue one signal in the chain of signals which need to be | |
4183 | delivered to this process on next resume. */ | |
4184 | ||
4185 | static void | |
4186 | enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info) | |
4187 | { | |
4188 | struct pending_signals *p_sig = XNEW (struct pending_signals); | |
4189 | ||
4190 | p_sig->prev = lwp->pending_signals; | |
4191 | p_sig->signal = signal; | |
4192 | if (info == NULL) | |
4193 | memset (&p_sig->info, 0, sizeof (siginfo_t)); | |
4194 | else | |
4195 | memcpy (&p_sig->info, info, sizeof (siginfo_t)); | |
4196 | lwp->pending_signals = p_sig; | |
4197 | } | |
4198 | ||
4199 | /* Install breakpoints for software single stepping. */ | |
4200 | ||
4201 | static void | |
4202 | install_software_single_step_breakpoints (struct lwp_info *lwp) | |
4203 | { | |
4204 | int i; | |
4205 | CORE_ADDR pc; | |
4206 | struct thread_info *thread = get_lwp_thread (lwp); | |
4207 | struct regcache *regcache = get_thread_regcache (thread, 1); | |
4208 | VEC (CORE_ADDR) *next_pcs = NULL; | |
4209 | struct cleanup *old_chain = make_cleanup_restore_current_thread (); | |
4210 | ||
4211 | make_cleanup (VEC_cleanup (CORE_ADDR), &next_pcs); | |
4212 | ||
4213 | current_thread = thread; | |
4214 | next_pcs = (*the_low_target.get_next_pcs) (regcache); | |
4215 | ||
4216 | for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i) | |
4217 | set_reinsert_breakpoint (pc, current_ptid); | |
4218 | ||
4219 | do_cleanups (old_chain); | |
4220 | } | |
4221 | ||
4222 | /* Single step via hardware or software single step. | |
4223 | Return 1 if hardware single stepping, 0 if software single stepping | |
4224 | or can't single step. */ | |
4225 | ||
4226 | static int | |
4227 | single_step (struct lwp_info* lwp) | |
4228 | { | |
4229 | int step = 0; | |
4230 | ||
4231 | if (can_hardware_single_step ()) | |
4232 | { | |
4233 | step = 1; | |
4234 | } | |
4235 | else if (can_software_single_step ()) | |
4236 | { | |
4237 | install_software_single_step_breakpoints (lwp); | |
4238 | step = 0; | |
4239 | } | |
4240 | else | |
4241 | { | |
4242 | if (debug_threads) | |
4243 | debug_printf ("stepping is not implemented on this target"); | |
4244 | } | |
4245 | ||
4246 | return step; | |
4247 | } | |
4248 | ||
4249 | /* The signal can be delivered to the inferior if we are not trying to | |
4250 | finish a fast tracepoint collect. Since signal can be delivered in | |
4251 | the step-over, the program may go to signal handler and trap again | |
4252 | after return from the signal handler. We can live with the spurious | |
4253 | double traps. */ | |
4254 | ||
4255 | static int | |
4256 | lwp_signal_can_be_delivered (struct lwp_info *lwp) | |
4257 | { | |
4258 | return !lwp->collecting_fast_tracepoint; | |
4259 | } | |
4260 | ||
4261 | /* Resume execution of LWP. If STEP is nonzero, single-step it. If | |
4262 | SIGNAL is nonzero, give it that signal. */ | |
4263 | ||
4264 | static void | |
4265 | linux_resume_one_lwp_throw (struct lwp_info *lwp, | |
4266 | int step, int signal, siginfo_t *info) | |
4267 | { | |
4268 | struct thread_info *thread = get_lwp_thread (lwp); | |
4269 | struct thread_info *saved_thread; | |
4270 | int fast_tp_collecting; | |
4271 | int ptrace_request; | |
4272 | struct process_info *proc = get_thread_process (thread); | |
4273 | ||
4274 | /* Note that target description may not be initialised | |
4275 | (proc->tdesc == NULL) at this point because the program hasn't | |
4276 | stopped at the first instruction yet. It means GDBserver skips | |
4277 | the extra traps from the wrapper program (see option --wrapper). | |
4278 | Code in this function that requires register access should be | |
4279 | guarded by proc->tdesc == NULL or something else. */ | |
4280 | ||
4281 | if (lwp->stopped == 0) | |
4282 | return; | |
4283 | ||
4284 | gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE); | |
4285 | ||
4286 | fast_tp_collecting = lwp->collecting_fast_tracepoint; | |
4287 | ||
4288 | gdb_assert (!stabilizing_threads || fast_tp_collecting); | |
4289 | ||
4290 | /* Cancel actions that rely on GDB not changing the PC (e.g., the | |
4291 | user used the "jump" command, or "set $pc = foo"). */ | |
4292 | if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp)) | |
4293 | { | |
4294 | /* Collecting 'while-stepping' actions doesn't make sense | |
4295 | anymore. */ | |
4296 | release_while_stepping_state_list (thread); | |
4297 | } | |
4298 | ||
4299 | /* If we have pending signals or status, and a new signal, enqueue the | |
4300 | signal. Also enqueue the signal if it can't be delivered to the | |
4301 | inferior right now. */ | |
4302 | if (signal != 0 | |
4303 | && (lwp->status_pending_p | |
4304 | || lwp->pending_signals != NULL | |
4305 | || !lwp_signal_can_be_delivered (lwp))) | |
4306 | { | |
4307 | enqueue_pending_signal (lwp, signal, info); | |
4308 | ||
4309 | /* Postpone any pending signal. It was enqueued above. */ | |
4310 | signal = 0; | |
4311 | } | |
4312 | ||
4313 | if (lwp->status_pending_p) | |
4314 | { | |
4315 | if (debug_threads) | |
4316 | debug_printf ("Not resuming lwp %ld (%s, stop %s);" | |
4317 | " has pending status\n", | |
4318 | lwpid_of (thread), step ? "step" : "continue", | |
4319 | lwp->stop_expected ? "expected" : "not expected"); | |
4320 | return; | |
4321 | } | |
4322 | ||
4323 | saved_thread = current_thread; | |
4324 | current_thread = thread; | |
4325 | ||
4326 | /* This bit needs some thinking about. If we get a signal that | |
4327 | we must report while a single-step reinsert is still pending, | |
4328 | we often end up resuming the thread. It might be better to | |
4329 | (ew) allow a stack of pending events; then we could be sure that | |
4330 | the reinsert happened right away and not lose any signals. | |
4331 | ||
4332 | Making this stack would also shrink the window in which breakpoints are | |
4333 | uninserted (see comment in linux_wait_for_lwp) but not enough for | |
4334 | complete correctness, so it won't solve that problem. It may be | |
4335 | worthwhile just to solve this one, however. */ | |
4336 | if (lwp->bp_reinsert != 0) | |
4337 | { | |
4338 | if (debug_threads) | |
4339 | debug_printf (" pending reinsert at 0x%s\n", | |
4340 | paddress (lwp->bp_reinsert)); | |
4341 | ||
4342 | if (can_hardware_single_step ()) | |
4343 | { | |
4344 | if (fast_tp_collecting == 0) | |
4345 | { | |
4346 | if (step == 0) | |
4347 | fprintf (stderr, "BAD - reinserting but not stepping.\n"); | |
4348 | if (lwp->suspended) | |
4349 | fprintf (stderr, "BAD - reinserting and suspended(%d).\n", | |
4350 | lwp->suspended); | |
4351 | } | |
4352 | } | |
4353 | ||
4354 | step = maybe_hw_step (thread); | |
4355 | } | |
4356 | else | |
4357 | { | |
4358 | /* If the thread isn't doing step-over, there shouldn't be any | |
4359 | reinsert breakpoints. */ | |
4360 | gdb_assert (!has_reinsert_breakpoints (thread)); | |
4361 | } | |
4362 | ||
4363 | if (fast_tp_collecting == 1) | |
4364 | { | |
4365 | if (debug_threads) | |
4366 | debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad" | |
4367 | " (exit-jump-pad-bkpt)\n", | |
4368 | lwpid_of (thread)); | |
4369 | } | |
4370 | else if (fast_tp_collecting == 2) | |
4371 | { | |
4372 | if (debug_threads) | |
4373 | debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad" | |
4374 | " single-stepping\n", | |
4375 | lwpid_of (thread)); | |
4376 | ||
4377 | if (can_hardware_single_step ()) | |
4378 | step = 1; | |
4379 | else | |
4380 | { | |
4381 | internal_error (__FILE__, __LINE__, | |
4382 | "moving out of jump pad single-stepping" | |
4383 | " not implemented on this target"); | |
4384 | } | |
4385 | } | |
4386 | ||
4387 | /* If we have while-stepping actions in this thread set it stepping. | |
4388 | If we have a signal to deliver, it may or may not be set to | |
4389 | SIG_IGN, we don't know. Assume so, and allow collecting | |
4390 | while-stepping into a signal handler. A possible smart thing to | |
4391 | do would be to set an internal breakpoint at the signal return | |
4392 | address, continue, and carry on catching this while-stepping | |
4393 | action only when that breakpoint is hit. A future | |
4394 | enhancement. */ | |
4395 | if (thread->while_stepping != NULL) | |
4396 | { | |
4397 | if (debug_threads) | |
4398 | debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n", | |
4399 | lwpid_of (thread)); | |
4400 | ||
4401 | step = single_step (lwp); | |
4402 | } | |
4403 | ||
4404 | if (proc->tdesc != NULL && the_low_target.get_pc != NULL) | |
4405 | { | |
4406 | struct regcache *regcache = get_thread_regcache (current_thread, 1); | |
4407 | ||
4408 | lwp->stop_pc = (*the_low_target.get_pc) (regcache); | |
4409 | ||
4410 | if (debug_threads) | |
4411 | { | |
4412 | debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue", | |
4413 | (long) lwp->stop_pc); | |
4414 | } | |
4415 | } | |
4416 | ||
4417 | /* If we have pending signals, consume one if it can be delivered to | |
4418 | the inferior. */ | |
4419 | if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp)) | |
4420 | { | |
4421 | struct pending_signals **p_sig; | |
4422 | ||
4423 | p_sig = &lwp->pending_signals; | |
4424 | while ((*p_sig)->prev != NULL) | |
4425 | p_sig = &(*p_sig)->prev; | |
4426 | ||
4427 | signal = (*p_sig)->signal; | |
4428 | if ((*p_sig)->info.si_signo != 0) | |
4429 | ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0, | |
4430 | &(*p_sig)->info); | |
4431 | ||
4432 | free (*p_sig); | |
4433 | *p_sig = NULL; | |
4434 | } | |
4435 | ||
4436 | if (debug_threads) | |
4437 | debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n", | |
4438 | lwpid_of (thread), step ? "step" : "continue", signal, | |
4439 | lwp->stop_expected ? "expected" : "not expected"); | |
4440 | ||
4441 | if (the_low_target.prepare_to_resume != NULL) | |
4442 | the_low_target.prepare_to_resume (lwp); | |
4443 | ||
4444 | regcache_invalidate_thread (thread); | |
4445 | errno = 0; | |
4446 | lwp->stepping = step; | |
4447 | if (step) | |
4448 | ptrace_request = PTRACE_SINGLESTEP; | |
4449 | else if (gdb_catching_syscalls_p (lwp)) | |
4450 | ptrace_request = PTRACE_SYSCALL; | |
4451 | else | |
4452 | ptrace_request = PTRACE_CONT; | |
4453 | ptrace (ptrace_request, | |
4454 | lwpid_of (thread), | |
4455 | (PTRACE_TYPE_ARG3) 0, | |
4456 | /* Coerce to a uintptr_t first to avoid potential gcc warning | |
4457 | of coercing an 8 byte integer to a 4 byte pointer. */ | |
4458 | (PTRACE_TYPE_ARG4) (uintptr_t) signal); | |
4459 | ||
4460 | current_thread = saved_thread; | |
4461 | if (errno) | |
4462 | perror_with_name ("resuming thread"); | |
4463 | ||
4464 | /* Successfully resumed. Clear state that no longer makes sense, | |
4465 | and mark the LWP as running. Must not do this before resuming | |
4466 | otherwise if that fails other code will be confused. E.g., we'd | |
4467 | later try to stop the LWP and hang forever waiting for a stop | |
4468 | status. Note that we must not throw after this is cleared, | |
4469 | otherwise handle_zombie_lwp_error would get confused. */ | |
4470 | lwp->stopped = 0; | |
4471 | lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
4472 | } | |
4473 | ||
4474 | /* Called when we try to resume a stopped LWP and that errors out. If | |
4475 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
4476 | or about to become), discard the error, clear any pending status | |
4477 | the LWP may have, and return true (we'll collect the exit status | |
4478 | soon enough). Otherwise, return false. */ | |
4479 | ||
4480 | static int | |
4481 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
4482 | { | |
4483 | struct thread_info *thread = get_lwp_thread (lp); | |
4484 | ||
4485 | /* If we get an error after resuming the LWP successfully, we'd | |
4486 | confuse !T state for the LWP being gone. */ | |
4487 | gdb_assert (lp->stopped); | |
4488 | ||
4489 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
4490 | because even if ptrace failed with ESRCH, the tracee may be "not | |
4491 | yet fully dead", but already refusing ptrace requests. In that | |
4492 | case the tracee has 'R (Running)' state for a little bit | |
4493 | (observed in Linux 3.18). See also the note on ESRCH in the | |
4494 | ptrace(2) man page. Instead, check whether the LWP has any state | |
4495 | other than ptrace-stopped. */ | |
4496 | ||
4497 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
4498 | if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0) | |
4499 | { | |
4500 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
4501 | lp->status_pending_p = 0; | |
4502 | return 1; | |
4503 | } | |
4504 | return 0; | |
4505 | } | |
4506 | ||
4507 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
4508 | disappears while we try to resume it. */ | |
4509 | ||
4510 | static void | |
4511 | linux_resume_one_lwp (struct lwp_info *lwp, | |
4512 | int step, int signal, siginfo_t *info) | |
4513 | { | |
4514 | TRY | |
4515 | { | |
4516 | linux_resume_one_lwp_throw (lwp, step, signal, info); | |
4517 | } | |
4518 | CATCH (ex, RETURN_MASK_ERROR) | |
4519 | { | |
4520 | if (!check_ptrace_stopped_lwp_gone (lwp)) | |
4521 | throw_exception (ex); | |
4522 | } | |
4523 | END_CATCH | |
4524 | } | |
4525 | ||
4526 | struct thread_resume_array | |
4527 | { | |
4528 | struct thread_resume *resume; | |
4529 | size_t n; | |
4530 | }; | |
4531 | ||
4532 | /* This function is called once per thread via find_inferior. | |
4533 | ARG is a pointer to a thread_resume_array struct. | |
4534 | We look up the thread specified by ENTRY in ARG, and mark the thread | |
4535 | with a pointer to the appropriate resume request. | |
4536 | ||
4537 | This algorithm is O(threads * resume elements), but resume elements | |
4538 | is small (and will remain small at least until GDB supports thread | |
4539 | suspension). */ | |
4540 | ||
4541 | static int | |
4542 | linux_set_resume_request (struct inferior_list_entry *entry, void *arg) | |
4543 | { | |
4544 | struct thread_info *thread = (struct thread_info *) entry; | |
4545 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4546 | int ndx; | |
4547 | struct thread_resume_array *r; | |
4548 | ||
4549 | r = (struct thread_resume_array *) arg; | |
4550 | ||
4551 | for (ndx = 0; ndx < r->n; ndx++) | |
4552 | { | |
4553 | ptid_t ptid = r->resume[ndx].thread; | |
4554 | if (ptid_equal (ptid, minus_one_ptid) | |
4555 | || ptid_equal (ptid, entry->id) | |
4556 | /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads | |
4557 | of PID'. */ | |
4558 | || (ptid_get_pid (ptid) == pid_of (thread) | |
4559 | && (ptid_is_pid (ptid) | |
4560 | || ptid_get_lwp (ptid) == -1))) | |
4561 | { | |
4562 | if (r->resume[ndx].kind == resume_stop | |
4563 | && thread->last_resume_kind == resume_stop) | |
4564 | { | |
4565 | if (debug_threads) | |
4566 | debug_printf ("already %s LWP %ld at GDB's request\n", | |
4567 | (thread->last_status.kind | |
4568 | == TARGET_WAITKIND_STOPPED) | |
4569 | ? "stopped" | |
4570 | : "stopping", | |
4571 | lwpid_of (thread)); | |
4572 | ||
4573 | continue; | |
4574 | } | |
4575 | ||
4576 | lwp->resume = &r->resume[ndx]; | |
4577 | thread->last_resume_kind = lwp->resume->kind; | |
4578 | ||
4579 | lwp->step_range_start = lwp->resume->step_range_start; | |
4580 | lwp->step_range_end = lwp->resume->step_range_end; | |
4581 | ||
4582 | /* If we had a deferred signal to report, dequeue one now. | |
4583 | This can happen if LWP gets more than one signal while | |
4584 | trying to get out of a jump pad. */ | |
4585 | if (lwp->stopped | |
4586 | && !lwp->status_pending_p | |
4587 | && dequeue_one_deferred_signal (lwp, &lwp->status_pending)) | |
4588 | { | |
4589 | lwp->status_pending_p = 1; | |
4590 | ||
4591 | if (debug_threads) | |
4592 | debug_printf ("Dequeueing deferred signal %d for LWP %ld, " | |
4593 | "leaving status pending.\n", | |
4594 | WSTOPSIG (lwp->status_pending), | |
4595 | lwpid_of (thread)); | |
4596 | } | |
4597 | ||
4598 | return 0; | |
4599 | } | |
4600 | } | |
4601 | ||
4602 | /* No resume action for this thread. */ | |
4603 | lwp->resume = NULL; | |
4604 | ||
4605 | return 0; | |
4606 | } | |
4607 | ||
4608 | /* find_inferior callback for linux_resume. | |
4609 | Set *FLAG_P if this lwp has an interesting status pending. */ | |
4610 | ||
4611 | static int | |
4612 | resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p) | |
4613 | { | |
4614 | struct thread_info *thread = (struct thread_info *) entry; | |
4615 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4616 | ||
4617 | /* LWPs which will not be resumed are not interesting, because | |
4618 | we might not wait for them next time through linux_wait. */ | |
4619 | if (lwp->resume == NULL) | |
4620 | return 0; | |
4621 | ||
4622 | if (thread_still_has_status_pending_p (thread)) | |
4623 | * (int *) flag_p = 1; | |
4624 | ||
4625 | return 0; | |
4626 | } | |
4627 | ||
4628 | /* Return 1 if this lwp that GDB wants running is stopped at an | |
4629 | internal breakpoint that we need to step over. It assumes that any | |
4630 | required STOP_PC adjustment has already been propagated to the | |
4631 | inferior's regcache. */ | |
4632 | ||
4633 | static int | |
4634 | need_step_over_p (struct inferior_list_entry *entry, void *dummy) | |
4635 | { | |
4636 | struct thread_info *thread = (struct thread_info *) entry; | |
4637 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4638 | struct thread_info *saved_thread; | |
4639 | CORE_ADDR pc; | |
4640 | struct process_info *proc = get_thread_process (thread); | |
4641 | ||
4642 | /* GDBserver is skipping the extra traps from the wrapper program, | |
4643 | don't have to do step over. */ | |
4644 | if (proc->tdesc == NULL) | |
4645 | return 0; | |
4646 | ||
4647 | /* LWPs which will not be resumed are not interesting, because we | |
4648 | might not wait for them next time through linux_wait. */ | |
4649 | ||
4650 | if (!lwp->stopped) | |
4651 | { | |
4652 | if (debug_threads) | |
4653 | debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n", | |
4654 | lwpid_of (thread)); | |
4655 | return 0; | |
4656 | } | |
4657 | ||
4658 | if (thread->last_resume_kind == resume_stop) | |
4659 | { | |
4660 | if (debug_threads) | |
4661 | debug_printf ("Need step over [LWP %ld]? Ignoring, should remain" | |
4662 | " stopped\n", | |
4663 | lwpid_of (thread)); | |
4664 | return 0; | |
4665 | } | |
4666 | ||
4667 | gdb_assert (lwp->suspended >= 0); | |
4668 | ||
4669 | if (lwp->suspended) | |
4670 | { | |
4671 | if (debug_threads) | |
4672 | debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n", | |
4673 | lwpid_of (thread)); | |
4674 | return 0; | |
4675 | } | |
4676 | ||
4677 | if (lwp->status_pending_p) | |
4678 | { | |
4679 | if (debug_threads) | |
4680 | debug_printf ("Need step over [LWP %ld]? Ignoring, has pending" | |
4681 | " status.\n", | |
4682 | lwpid_of (thread)); | |
4683 | return 0; | |
4684 | } | |
4685 | ||
4686 | /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already, | |
4687 | or we have. */ | |
4688 | pc = get_pc (lwp); | |
4689 | ||
4690 | /* If the PC has changed since we stopped, then don't do anything, | |
4691 | and let the breakpoint/tracepoint be hit. This happens if, for | |
4692 | instance, GDB handled the decr_pc_after_break subtraction itself, | |
4693 | GDB is OOL stepping this thread, or the user has issued a "jump" | |
4694 | command, or poked thread's registers herself. */ | |
4695 | if (pc != lwp->stop_pc) | |
4696 | { | |
4697 | if (debug_threads) | |
4698 | debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. " | |
4699 | "Old stop_pc was 0x%s, PC is now 0x%s\n", | |
4700 | lwpid_of (thread), | |
4701 | paddress (lwp->stop_pc), paddress (pc)); | |
4702 | return 0; | |
4703 | } | |
4704 | ||
4705 | /* On software single step target, resume the inferior with signal | |
4706 | rather than stepping over. */ | |
4707 | if (can_software_single_step () | |
4708 | && lwp->pending_signals != NULL | |
4709 | && lwp_signal_can_be_delivered (lwp)) | |
4710 | { | |
4711 | if (debug_threads) | |
4712 | debug_printf ("Need step over [LWP %ld]? Ignoring, has pending" | |
4713 | " signals.\n", | |
4714 | lwpid_of (thread)); | |
4715 | ||
4716 | return 0; | |
4717 | } | |
4718 | ||
4719 | saved_thread = current_thread; | |
4720 | current_thread = thread; | |
4721 | ||
4722 | /* We can only step over breakpoints we know about. */ | |
4723 | if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc)) | |
4724 | { | |
4725 | /* Don't step over a breakpoint that GDB expects to hit | |
4726 | though. If the condition is being evaluated on the target's side | |
4727 | and it evaluate to false, step over this breakpoint as well. */ | |
4728 | if (gdb_breakpoint_here (pc) | |
4729 | && gdb_condition_true_at_breakpoint (pc) | |
4730 | && gdb_no_commands_at_breakpoint (pc)) | |
4731 | { | |
4732 | if (debug_threads) | |
4733 | debug_printf ("Need step over [LWP %ld]? yes, but found" | |
4734 | " GDB breakpoint at 0x%s; skipping step over\n", | |
4735 | lwpid_of (thread), paddress (pc)); | |
4736 | ||
4737 | current_thread = saved_thread; | |
4738 | return 0; | |
4739 | } | |
4740 | else | |
4741 | { | |
4742 | if (debug_threads) | |
4743 | debug_printf ("Need step over [LWP %ld]? yes, " | |
4744 | "found breakpoint at 0x%s\n", | |
4745 | lwpid_of (thread), paddress (pc)); | |
4746 | ||
4747 | /* We've found an lwp that needs stepping over --- return 1 so | |
4748 | that find_inferior stops looking. */ | |
4749 | current_thread = saved_thread; | |
4750 | ||
4751 | return 1; | |
4752 | } | |
4753 | } | |
4754 | ||
4755 | current_thread = saved_thread; | |
4756 | ||
4757 | if (debug_threads) | |
4758 | debug_printf ("Need step over [LWP %ld]? No, no breakpoint found" | |
4759 | " at 0x%s\n", | |
4760 | lwpid_of (thread), paddress (pc)); | |
4761 | ||
4762 | return 0; | |
4763 | } | |
4764 | ||
4765 | /* Start a step-over operation on LWP. When LWP stopped at a | |
4766 | breakpoint, to make progress, we need to remove the breakpoint out | |
4767 | of the way. If we let other threads run while we do that, they may | |
4768 | pass by the breakpoint location and miss hitting it. To avoid | |
4769 | that, a step-over momentarily stops all threads while LWP is | |
4770 | single-stepped by either hardware or software while the breakpoint | |
4771 | is temporarily uninserted from the inferior. When the single-step | |
4772 | finishes, we reinsert the breakpoint, and let all threads that are | |
4773 | supposed to be running, run again. */ | |
4774 | ||
4775 | static int | |
4776 | start_step_over (struct lwp_info *lwp) | |
4777 | { | |
4778 | struct thread_info *thread = get_lwp_thread (lwp); | |
4779 | struct thread_info *saved_thread; | |
4780 | CORE_ADDR pc; | |
4781 | int step; | |
4782 | ||
4783 | if (debug_threads) | |
4784 | debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n", | |
4785 | lwpid_of (thread)); | |
4786 | ||
4787 | stop_all_lwps (1, lwp); | |
4788 | ||
4789 | if (lwp->suspended != 0) | |
4790 | { | |
4791 | internal_error (__FILE__, __LINE__, | |
4792 | "LWP %ld suspended=%d\n", lwpid_of (thread), | |
4793 | lwp->suspended); | |
4794 | } | |
4795 | ||
4796 | if (debug_threads) | |
4797 | debug_printf ("Done stopping all threads for step-over.\n"); | |
4798 | ||
4799 | /* Note, we should always reach here with an already adjusted PC, | |
4800 | either by GDB (if we're resuming due to GDB's request), or by our | |
4801 | caller, if we just finished handling an internal breakpoint GDB | |
4802 | shouldn't care about. */ | |
4803 | pc = get_pc (lwp); | |
4804 | ||
4805 | saved_thread = current_thread; | |
4806 | current_thread = thread; | |
4807 | ||
4808 | lwp->bp_reinsert = pc; | |
4809 | uninsert_breakpoints_at (pc); | |
4810 | uninsert_fast_tracepoint_jumps_at (pc); | |
4811 | ||
4812 | step = single_step (lwp); | |
4813 | ||
4814 | current_thread = saved_thread; | |
4815 | ||
4816 | linux_resume_one_lwp (lwp, step, 0, NULL); | |
4817 | ||
4818 | /* Require next event from this LWP. */ | |
4819 | step_over_bkpt = thread->entry.id; | |
4820 | return 1; | |
4821 | } | |
4822 | ||
4823 | /* Finish a step-over. Reinsert the breakpoint we had uninserted in | |
4824 | start_step_over, if still there, and delete any reinsert | |
4825 | breakpoints we've set, on non hardware single-step targets. */ | |
4826 | ||
4827 | static int | |
4828 | finish_step_over (struct lwp_info *lwp) | |
4829 | { | |
4830 | if (lwp->bp_reinsert != 0) | |
4831 | { | |
4832 | struct thread_info *saved_thread = current_thread; | |
4833 | ||
4834 | if (debug_threads) | |
4835 | debug_printf ("Finished step over.\n"); | |
4836 | ||
4837 | current_thread = get_lwp_thread (lwp); | |
4838 | ||
4839 | /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there | |
4840 | may be no breakpoint to reinsert there by now. */ | |
4841 | reinsert_breakpoints_at (lwp->bp_reinsert); | |
4842 | reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert); | |
4843 | ||
4844 | lwp->bp_reinsert = 0; | |
4845 | ||
4846 | /* Delete any software-single-step reinsert breakpoints. No | |
4847 | longer needed. We don't have to worry about other threads | |
4848 | hitting this trap, and later not being able to explain it, | |
4849 | because we were stepping over a breakpoint, and we hold all | |
4850 | threads but LWP stopped while doing that. */ | |
4851 | if (!can_hardware_single_step ()) | |
4852 | { | |
4853 | gdb_assert (has_reinsert_breakpoints (current_thread)); | |
4854 | delete_reinsert_breakpoints (current_thread); | |
4855 | } | |
4856 | ||
4857 | step_over_bkpt = null_ptid; | |
4858 | current_thread = saved_thread; | |
4859 | return 1; | |
4860 | } | |
4861 | else | |
4862 | return 0; | |
4863 | } | |
4864 | ||
4865 | /* If there's a step over in progress, wait until all threads stop | |
4866 | (that is, until the stepping thread finishes its step), and | |
4867 | unsuspend all lwps. The stepping thread ends with its status | |
4868 | pending, which is processed later when we get back to processing | |
4869 | events. */ | |
4870 | ||
4871 | static void | |
4872 | complete_ongoing_step_over (void) | |
4873 | { | |
4874 | if (!ptid_equal (step_over_bkpt, null_ptid)) | |
4875 | { | |
4876 | struct lwp_info *lwp; | |
4877 | int wstat; | |
4878 | int ret; | |
4879 | ||
4880 | if (debug_threads) | |
4881 | debug_printf ("detach: step over in progress, finish it first\n"); | |
4882 | ||
4883 | /* Passing NULL_PTID as filter indicates we want all events to | |
4884 | be left pending. Eventually this returns when there are no | |
4885 | unwaited-for children left. */ | |
4886 | ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid, | |
4887 | &wstat, __WALL); | |
4888 | gdb_assert (ret == -1); | |
4889 | ||
4890 | lwp = find_lwp_pid (step_over_bkpt); | |
4891 | if (lwp != NULL) | |
4892 | finish_step_over (lwp); | |
4893 | step_over_bkpt = null_ptid; | |
4894 | unsuspend_all_lwps (lwp); | |
4895 | } | |
4896 | } | |
4897 | ||
4898 | /* This function is called once per thread. We check the thread's resume | |
4899 | request, which will tell us whether to resume, step, or leave the thread | |
4900 | stopped; and what signal, if any, it should be sent. | |
4901 | ||
4902 | For threads which we aren't explicitly told otherwise, we preserve | |
4903 | the stepping flag; this is used for stepping over gdbserver-placed | |
4904 | breakpoints. | |
4905 | ||
4906 | If pending_flags was set in any thread, we queue any needed | |
4907 | signals, since we won't actually resume. We already have a pending | |
4908 | event to report, so we don't need to preserve any step requests; | |
4909 | they should be re-issued if necessary. */ | |
4910 | ||
4911 | static int | |
4912 | linux_resume_one_thread (struct inferior_list_entry *entry, void *arg) | |
4913 | { | |
4914 | struct thread_info *thread = (struct thread_info *) entry; | |
4915 | struct lwp_info *lwp = get_thread_lwp (thread); | |
4916 | int leave_all_stopped = * (int *) arg; | |
4917 | int leave_pending; | |
4918 | ||
4919 | if (lwp->resume == NULL) | |
4920 | return 0; | |
4921 | ||
4922 | if (lwp->resume->kind == resume_stop) | |
4923 | { | |
4924 | if (debug_threads) | |
4925 | debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread)); | |
4926 | ||
4927 | if (!lwp->stopped) | |
4928 | { | |
4929 | if (debug_threads) | |
4930 | debug_printf ("stopping LWP %ld\n", lwpid_of (thread)); | |
4931 | ||
4932 | /* Stop the thread, and wait for the event asynchronously, | |
4933 | through the event loop. */ | |
4934 | send_sigstop (lwp); | |
4935 | } | |
4936 | else | |
4937 | { | |
4938 | if (debug_threads) | |
4939 | debug_printf ("already stopped LWP %ld\n", | |
4940 | lwpid_of (thread)); | |
4941 | ||
4942 | /* The LWP may have been stopped in an internal event that | |
4943 | was not meant to be notified back to GDB (e.g., gdbserver | |
4944 | breakpoint), so we should be reporting a stop event in | |
4945 | this case too. */ | |
4946 | ||
4947 | /* If the thread already has a pending SIGSTOP, this is a | |
4948 | no-op. Otherwise, something later will presumably resume | |
4949 | the thread and this will cause it to cancel any pending | |
4950 | operation, due to last_resume_kind == resume_stop. If | |
4951 | the thread already has a pending status to report, we | |
4952 | will still report it the next time we wait - see | |
4953 | status_pending_p_callback. */ | |
4954 | ||
4955 | /* If we already have a pending signal to report, then | |
4956 | there's no need to queue a SIGSTOP, as this means we're | |
4957 | midway through moving the LWP out of the jumppad, and we | |
4958 | will report the pending signal as soon as that is | |
4959 | finished. */ | |
4960 | if (lwp->pending_signals_to_report == NULL) | |
4961 | send_sigstop (lwp); | |
4962 | } | |
4963 | ||
4964 | /* For stop requests, we're done. */ | |
4965 | lwp->resume = NULL; | |
4966 | thread->last_status.kind = TARGET_WAITKIND_IGNORE; | |
4967 | return 0; | |
4968 | } | |
4969 | ||
4970 | /* If this thread which is about to be resumed has a pending status, | |
4971 | then don't resume it - we can just report the pending status. | |
4972 | Likewise if it is suspended, because e.g., another thread is | |
4973 | stepping past a breakpoint. Make sure to queue any signals that | |
4974 | would otherwise be sent. In all-stop mode, we do this decision | |
4975 | based on if *any* thread has a pending status. If there's a | |
4976 | thread that needs the step-over-breakpoint dance, then don't | |
4977 | resume any other thread but that particular one. */ | |
4978 | leave_pending = (lwp->suspended | |
4979 | || lwp->status_pending_p | |
4980 | || leave_all_stopped); | |
4981 | ||
4982 | /* If we have a new signal, enqueue the signal. */ | |
4983 | if (lwp->resume->sig != 0) | |
4984 | { | |
4985 | siginfo_t info, *info_p; | |
4986 | ||
4987 | /* If this is the same signal we were previously stopped by, | |
4988 | make sure to queue its siginfo. */ | |
4989 | if (WIFSTOPPED (lwp->last_status) | |
4990 | && WSTOPSIG (lwp->last_status) == lwp->resume->sig | |
4991 | && ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), | |
4992 | (PTRACE_TYPE_ARG3) 0, &info) == 0) | |
4993 | info_p = &info; | |
4994 | else | |
4995 | info_p = NULL; | |
4996 | ||
4997 | enqueue_pending_signal (lwp, lwp->resume->sig, info_p); | |
4998 | } | |
4999 | ||
5000 | if (!leave_pending) | |
5001 | { | |
5002 | if (debug_threads) | |
5003 | debug_printf ("resuming LWP %ld\n", lwpid_of (thread)); | |
5004 | ||
5005 | proceed_one_lwp (entry, NULL); | |
5006 | } | |
5007 | else | |
5008 | { | |
5009 | if (debug_threads) | |
5010 | debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread)); | |
5011 | } | |
5012 | ||
5013 | thread->last_status.kind = TARGET_WAITKIND_IGNORE; | |
5014 | lwp->resume = NULL; | |
5015 | return 0; | |
5016 | } | |
5017 | ||
5018 | static void | |
5019 | linux_resume (struct thread_resume *resume_info, size_t n) | |
5020 | { | |
5021 | struct thread_resume_array array = { resume_info, n }; | |
5022 | struct thread_info *need_step_over = NULL; | |
5023 | int any_pending; | |
5024 | int leave_all_stopped; | |
5025 | ||
5026 | if (debug_threads) | |
5027 | { | |
5028 | debug_enter (); | |
5029 | debug_printf ("linux_resume:\n"); | |
5030 | } | |
5031 | ||
5032 | find_inferior (&all_threads, linux_set_resume_request, &array); | |
5033 | ||
5034 | /* If there is a thread which would otherwise be resumed, which has | |
5035 | a pending status, then don't resume any threads - we can just | |
5036 | report the pending status. Make sure to queue any signals that | |
5037 | would otherwise be sent. In non-stop mode, we'll apply this | |
5038 | logic to each thread individually. We consume all pending events | |
5039 | before considering to start a step-over (in all-stop). */ | |
5040 | any_pending = 0; | |
5041 | if (!non_stop) | |
5042 | find_inferior (&all_threads, resume_status_pending_p, &any_pending); | |
5043 | ||
5044 | /* If there is a thread which would otherwise be resumed, which is | |
5045 | stopped at a breakpoint that needs stepping over, then don't | |
5046 | resume any threads - have it step over the breakpoint with all | |
5047 | other threads stopped, then resume all threads again. Make sure | |
5048 | to queue any signals that would otherwise be delivered or | |
5049 | queued. */ | |
5050 | if (!any_pending && supports_breakpoints ()) | |
5051 | need_step_over | |
5052 | = (struct thread_info *) find_inferior (&all_threads, | |
5053 | need_step_over_p, NULL); | |
5054 | ||
5055 | leave_all_stopped = (need_step_over != NULL || any_pending); | |
5056 | ||
5057 | if (debug_threads) | |
5058 | { | |
5059 | if (need_step_over != NULL) | |
5060 | debug_printf ("Not resuming all, need step over\n"); | |
5061 | else if (any_pending) | |
5062 | debug_printf ("Not resuming, all-stop and found " | |
5063 | "an LWP with pending status\n"); | |
5064 | else | |
5065 | debug_printf ("Resuming, no pending status or step over needed\n"); | |
5066 | } | |
5067 | ||
5068 | /* Even if we're leaving threads stopped, queue all signals we'd | |
5069 | otherwise deliver. */ | |
5070 | find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped); | |
5071 | ||
5072 | if (need_step_over) | |
5073 | start_step_over (get_thread_lwp (need_step_over)); | |
5074 | ||
5075 | if (debug_threads) | |
5076 | { | |
5077 | debug_printf ("linux_resume done\n"); | |
5078 | debug_exit (); | |
5079 | } | |
5080 | ||
5081 | /* We may have events that were pending that can/should be sent to | |
5082 | the client now. Trigger a linux_wait call. */ | |
5083 | if (target_is_async_p ()) | |
5084 | async_file_mark (); | |
5085 | } | |
5086 | ||
5087 | /* This function is called once per thread. We check the thread's | |
5088 | last resume request, which will tell us whether to resume, step, or | |
5089 | leave the thread stopped. Any signal the client requested to be | |
5090 | delivered has already been enqueued at this point. | |
5091 | ||
5092 | If any thread that GDB wants running is stopped at an internal | |
5093 | breakpoint that needs stepping over, we start a step-over operation | |
5094 | on that particular thread, and leave all others stopped. */ | |
5095 | ||
5096 | static int | |
5097 | proceed_one_lwp (struct inferior_list_entry *entry, void *except) | |
5098 | { | |
5099 | struct thread_info *thread = (struct thread_info *) entry; | |
5100 | struct lwp_info *lwp = get_thread_lwp (thread); | |
5101 | int step; | |
5102 | ||
5103 | if (lwp == except) | |
5104 | return 0; | |
5105 | ||
5106 | if (debug_threads) | |
5107 | debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread)); | |
5108 | ||
5109 | if (!lwp->stopped) | |
5110 | { | |
5111 | if (debug_threads) | |
5112 | debug_printf (" LWP %ld already running\n", lwpid_of (thread)); | |
5113 | return 0; | |
5114 | } | |
5115 | ||
5116 | if (thread->last_resume_kind == resume_stop | |
5117 | && thread->last_status.kind != TARGET_WAITKIND_IGNORE) | |
5118 | { | |
5119 | if (debug_threads) | |
5120 | debug_printf (" client wants LWP to remain %ld stopped\n", | |
5121 | lwpid_of (thread)); | |
5122 | return 0; | |
5123 | } | |
5124 | ||
5125 | if (lwp->status_pending_p) | |
5126 | { | |
5127 | if (debug_threads) | |
5128 | debug_printf (" LWP %ld has pending status, leaving stopped\n", | |
5129 | lwpid_of (thread)); | |
5130 | return 0; | |
5131 | } | |
5132 | ||
5133 | gdb_assert (lwp->suspended >= 0); | |
5134 | ||
5135 | if (lwp->suspended) | |
5136 | { | |
5137 | if (debug_threads) | |
5138 | debug_printf (" LWP %ld is suspended\n", lwpid_of (thread)); | |
5139 | return 0; | |
5140 | } | |
5141 | ||
5142 | if (thread->last_resume_kind == resume_stop | |
5143 | && lwp->pending_signals_to_report == NULL | |
5144 | && lwp->collecting_fast_tracepoint == 0) | |
5145 | { | |
5146 | /* We haven't reported this LWP as stopped yet (otherwise, the | |
5147 | last_status.kind check above would catch it, and we wouldn't | |
5148 | reach here. This LWP may have been momentarily paused by a | |
5149 | stop_all_lwps call while handling for example, another LWP's | |
5150 | step-over. In that case, the pending expected SIGSTOP signal | |
5151 | that was queued at vCont;t handling time will have already | |
5152 | been consumed by wait_for_sigstop, and so we need to requeue | |
5153 | another one here. Note that if the LWP already has a SIGSTOP | |
5154 | pending, this is a no-op. */ | |
5155 | ||
5156 | if (debug_threads) | |
5157 | debug_printf ("Client wants LWP %ld to stop. " | |
5158 | "Making sure it has a SIGSTOP pending\n", | |
5159 | lwpid_of (thread)); | |
5160 | ||
5161 | send_sigstop (lwp); | |
5162 | } | |
5163 | ||
5164 | if (thread->last_resume_kind == resume_step) | |
5165 | { | |
5166 | if (debug_threads) | |
5167 | debug_printf (" stepping LWP %ld, client wants it stepping\n", | |
5168 | lwpid_of (thread)); | |
5169 | step = 1; | |
5170 | } | |
5171 | else if (lwp->bp_reinsert != 0) | |
5172 | { | |
5173 | if (debug_threads) | |
5174 | debug_printf (" stepping LWP %ld, reinsert set\n", | |
5175 | lwpid_of (thread)); | |
5176 | ||
5177 | step = maybe_hw_step (thread); | |
5178 | } | |
5179 | else | |
5180 | step = 0; | |
5181 | ||
5182 | linux_resume_one_lwp (lwp, step, 0, NULL); | |
5183 | return 0; | |
5184 | } | |
5185 | ||
5186 | static int | |
5187 | unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except) | |
5188 | { | |
5189 | struct thread_info *thread = (struct thread_info *) entry; | |
5190 | struct lwp_info *lwp = get_thread_lwp (thread); | |
5191 | ||
5192 | if (lwp == except) | |
5193 | return 0; | |
5194 | ||
5195 | lwp_suspended_decr (lwp); | |
5196 | ||
5197 | return proceed_one_lwp (entry, except); | |
5198 | } | |
5199 | ||
5200 | /* When we finish a step-over, set threads running again. If there's | |
5201 | another thread that may need a step-over, now's the time to start | |
5202 | it. Eventually, we'll move all threads past their breakpoints. */ | |
5203 | ||
5204 | static void | |
5205 | proceed_all_lwps (void) | |
5206 | { | |
5207 | struct thread_info *need_step_over; | |
5208 | ||
5209 | /* If there is a thread which would otherwise be resumed, which is | |
5210 | stopped at a breakpoint that needs stepping over, then don't | |
5211 | resume any threads - have it step over the breakpoint with all | |
5212 | other threads stopped, then resume all threads again. */ | |
5213 | ||
5214 | if (supports_breakpoints ()) | |
5215 | { | |
5216 | need_step_over | |
5217 | = (struct thread_info *) find_inferior (&all_threads, | |
5218 | need_step_over_p, NULL); | |
5219 | ||
5220 | if (need_step_over != NULL) | |
5221 | { | |
5222 | if (debug_threads) | |
5223 | debug_printf ("proceed_all_lwps: found " | |
5224 | "thread %ld needing a step-over\n", | |
5225 | lwpid_of (need_step_over)); | |
5226 | ||
5227 | start_step_over (get_thread_lwp (need_step_over)); | |
5228 | return; | |
5229 | } | |
5230 | } | |
5231 | ||
5232 | if (debug_threads) | |
5233 | debug_printf ("Proceeding, no step-over needed\n"); | |
5234 | ||
5235 | find_inferior (&all_threads, proceed_one_lwp, NULL); | |
5236 | } | |
5237 | ||
5238 | /* Stopped LWPs that the client wanted to be running, that don't have | |
5239 | pending statuses, are set to run again, except for EXCEPT, if not | |
5240 | NULL. This undoes a stop_all_lwps call. */ | |
5241 | ||
5242 | static void | |
5243 | unstop_all_lwps (int unsuspend, struct lwp_info *except) | |
5244 | { | |
5245 | if (debug_threads) | |
5246 | { | |
5247 | debug_enter (); | |
5248 | if (except) | |
5249 | debug_printf ("unstopping all lwps, except=(LWP %ld)\n", | |
5250 | lwpid_of (get_lwp_thread (except))); | |
5251 | else | |
5252 | debug_printf ("unstopping all lwps\n"); | |
5253 | } | |
5254 | ||
5255 | if (unsuspend) | |
5256 | find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except); | |
5257 | else | |
5258 | find_inferior (&all_threads, proceed_one_lwp, except); | |
5259 | ||
5260 | if (debug_threads) | |
5261 | { | |
5262 | debug_printf ("unstop_all_lwps done\n"); | |
5263 | debug_exit (); | |
5264 | } | |
5265 | } | |
5266 | ||
5267 | ||
5268 | #ifdef HAVE_LINUX_REGSETS | |
5269 | ||
5270 | #define use_linux_regsets 1 | |
5271 | ||
5272 | /* Returns true if REGSET has been disabled. */ | |
5273 | ||
5274 | static int | |
5275 | regset_disabled (struct regsets_info *info, struct regset_info *regset) | |
5276 | { | |
5277 | return (info->disabled_regsets != NULL | |
5278 | && info->disabled_regsets[regset - info->regsets]); | |
5279 | } | |
5280 | ||
5281 | /* Disable REGSET. */ | |
5282 | ||
5283 | static void | |
5284 | disable_regset (struct regsets_info *info, struct regset_info *regset) | |
5285 | { | |
5286 | int dr_offset; | |
5287 | ||
5288 | dr_offset = regset - info->regsets; | |
5289 | if (info->disabled_regsets == NULL) | |
5290 | info->disabled_regsets = (char *) xcalloc (1, info->num_regsets); | |
5291 | info->disabled_regsets[dr_offset] = 1; | |
5292 | } | |
5293 | ||
5294 | static int | |
5295 | regsets_fetch_inferior_registers (struct regsets_info *regsets_info, | |
5296 | struct regcache *regcache) | |
5297 | { | |
5298 | struct regset_info *regset; | |
5299 | int saw_general_regs = 0; | |
5300 | int pid; | |
5301 | struct iovec iov; | |
5302 | ||
5303 | pid = lwpid_of (current_thread); | |
5304 | for (regset = regsets_info->regsets; regset->size >= 0; regset++) | |
5305 | { | |
5306 | void *buf, *data; | |
5307 | int nt_type, res; | |
5308 | ||
5309 | if (regset->size == 0 || regset_disabled (regsets_info, regset)) | |
5310 | continue; | |
5311 | ||
5312 | buf = xmalloc (regset->size); | |
5313 | ||
5314 | nt_type = regset->nt_type; | |
5315 | if (nt_type) | |
5316 | { | |
5317 | iov.iov_base = buf; | |
5318 | iov.iov_len = regset->size; | |
5319 | data = (void *) &iov; | |
5320 | } | |
5321 | else | |
5322 | data = buf; | |
5323 | ||
5324 | #ifndef __sparc__ | |
5325 | res = ptrace (regset->get_request, pid, | |
5326 | (PTRACE_TYPE_ARG3) (long) nt_type, data); | |
5327 | #else | |
5328 | res = ptrace (regset->get_request, pid, data, nt_type); | |
5329 | #endif | |
5330 | if (res < 0) | |
5331 | { | |
5332 | if (errno == EIO) | |
5333 | { | |
5334 | /* If we get EIO on a regset, do not try it again for | |
5335 | this process mode. */ | |
5336 | disable_regset (regsets_info, regset); | |
5337 | } | |
5338 | else if (errno == ENODATA) | |
5339 | { | |
5340 | /* ENODATA may be returned if the regset is currently | |
5341 | not "active". This can happen in normal operation, | |
5342 | so suppress the warning in this case. */ | |
5343 | } | |
5344 | else | |
5345 | { | |
5346 | char s[256]; | |
5347 | sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d", | |
5348 | pid); | |
5349 | perror (s); | |
5350 | } | |
5351 | } | |
5352 | else | |
5353 | { | |
5354 | if (regset->type == GENERAL_REGS) | |
5355 | saw_general_regs = 1; | |
5356 | regset->store_function (regcache, buf); | |
5357 | } | |
5358 | free (buf); | |
5359 | } | |
5360 | if (saw_general_regs) | |
5361 | return 0; | |
5362 | else | |
5363 | return 1; | |
5364 | } | |
5365 | ||
5366 | static int | |
5367 | regsets_store_inferior_registers (struct regsets_info *regsets_info, | |
5368 | struct regcache *regcache) | |
5369 | { | |
5370 | struct regset_info *regset; | |
5371 | int saw_general_regs = 0; | |
5372 | int pid; | |
5373 | struct iovec iov; | |
5374 | ||
5375 | pid = lwpid_of (current_thread); | |
5376 | for (regset = regsets_info->regsets; regset->size >= 0; regset++) | |
5377 | { | |
5378 | void *buf, *data; | |
5379 | int nt_type, res; | |
5380 | ||
5381 | if (regset->size == 0 || regset_disabled (regsets_info, regset) | |
5382 | || regset->fill_function == NULL) | |
5383 | continue; | |
5384 | ||
5385 | buf = xmalloc (regset->size); | |
5386 | ||
5387 | /* First fill the buffer with the current register set contents, | |
5388 | in case there are any items in the kernel's regset that are | |
5389 | not in gdbserver's regcache. */ | |
5390 | ||
5391 | nt_type = regset->nt_type; | |
5392 | if (nt_type) | |
5393 | { | |
5394 | iov.iov_base = buf; | |
5395 | iov.iov_len = regset->size; | |
5396 | data = (void *) &iov; | |
5397 | } | |
5398 | else | |
5399 | data = buf; | |
5400 | ||
5401 | #ifndef __sparc__ | |
5402 | res = ptrace (regset->get_request, pid, | |
5403 | (PTRACE_TYPE_ARG3) (long) nt_type, data); | |
5404 | #else | |
5405 | res = ptrace (regset->get_request, pid, data, nt_type); | |
5406 | #endif | |
5407 | ||
5408 | if (res == 0) | |
5409 | { | |
5410 | /* Then overlay our cached registers on that. */ | |
5411 | regset->fill_function (regcache, buf); | |
5412 | ||
5413 | /* Only now do we write the register set. */ | |
5414 | #ifndef __sparc__ | |
5415 | res = ptrace (regset->set_request, pid, | |
5416 | (PTRACE_TYPE_ARG3) (long) nt_type, data); | |
5417 | #else | |
5418 | res = ptrace (regset->set_request, pid, data, nt_type); | |
5419 | #endif | |
5420 | } | |
5421 | ||
5422 | if (res < 0) | |
5423 | { | |
5424 | if (errno == EIO) | |
5425 | { | |
5426 | /* If we get EIO on a regset, do not try it again for | |
5427 | this process mode. */ | |
5428 | disable_regset (regsets_info, regset); | |
5429 | } | |
5430 | else if (errno == ESRCH) | |
5431 | { | |
5432 | /* At this point, ESRCH should mean the process is | |
5433 | already gone, in which case we simply ignore attempts | |
5434 | to change its registers. See also the related | |
5435 | comment in linux_resume_one_lwp. */ | |
5436 | free (buf); | |
5437 | return 0; | |
5438 | } | |
5439 | else | |
5440 | { | |
5441 | perror ("Warning: ptrace(regsets_store_inferior_registers)"); | |
5442 | } | |
5443 | } | |
5444 | else if (regset->type == GENERAL_REGS) | |
5445 | saw_general_regs = 1; | |
5446 | free (buf); | |
5447 | } | |
5448 | if (saw_general_regs) | |
5449 | return 0; | |
5450 | else | |
5451 | return 1; | |
5452 | } | |
5453 | ||
5454 | #else /* !HAVE_LINUX_REGSETS */ | |
5455 | ||
5456 | #define use_linux_regsets 0 | |
5457 | #define regsets_fetch_inferior_registers(regsets_info, regcache) 1 | |
5458 | #define regsets_store_inferior_registers(regsets_info, regcache) 1 | |
5459 | ||
5460 | #endif | |
5461 | ||
5462 | /* Return 1 if register REGNO is supported by one of the regset ptrace | |
5463 | calls or 0 if it has to be transferred individually. */ | |
5464 | ||
5465 | static int | |
5466 | linux_register_in_regsets (const struct regs_info *regs_info, int regno) | |
5467 | { | |
5468 | unsigned char mask = 1 << (regno % 8); | |
5469 | size_t index = regno / 8; | |
5470 | ||
5471 | return (use_linux_regsets | |
5472 | && (regs_info->regset_bitmap == NULL | |
5473 | || (regs_info->regset_bitmap[index] & mask) != 0)); | |
5474 | } | |
5475 | ||
5476 | #ifdef HAVE_LINUX_USRREGS | |
5477 | ||
5478 | static int | |
5479 | register_addr (const struct usrregs_info *usrregs, int regnum) | |
5480 | { | |
5481 | int addr; | |
5482 | ||
5483 | if (regnum < 0 || regnum >= usrregs->num_regs) | |
5484 | error ("Invalid register number %d.", regnum); | |
5485 | ||
5486 | addr = usrregs->regmap[regnum]; | |
5487 | ||
5488 | return addr; | |
5489 | } | |
5490 | ||
5491 | /* Fetch one register. */ | |
5492 | static void | |
5493 | fetch_register (const struct usrregs_info *usrregs, | |
5494 | struct regcache *regcache, int regno) | |
5495 | { | |
5496 | CORE_ADDR regaddr; | |
5497 | int i, size; | |
5498 | char *buf; | |
5499 | int pid; | |
5500 | ||
5501 | if (regno >= usrregs->num_regs) | |
5502 | return; | |
5503 | if ((*the_low_target.cannot_fetch_register) (regno)) | |
5504 | return; | |
5505 | ||
5506 | regaddr = register_addr (usrregs, regno); | |
5507 | if (regaddr == -1) | |
5508 | return; | |
5509 | ||
5510 | size = ((register_size (regcache->tdesc, regno) | |
5511 | + sizeof (PTRACE_XFER_TYPE) - 1) | |
5512 | & -sizeof (PTRACE_XFER_TYPE)); | |
5513 | buf = (char *) alloca (size); | |
5514 | ||
5515 | pid = lwpid_of (current_thread); | |
5516 | for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE)) | |
5517 | { | |
5518 | errno = 0; | |
5519 | *(PTRACE_XFER_TYPE *) (buf + i) = | |
5520 | ptrace (PTRACE_PEEKUSER, pid, | |
5521 | /* Coerce to a uintptr_t first to avoid potential gcc warning | |
5522 | of coercing an 8 byte integer to a 4 byte pointer. */ | |
5523 | (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0); | |
5524 | regaddr += sizeof (PTRACE_XFER_TYPE); | |
5525 | if (errno != 0) | |
5526 | error ("reading register %d: %s", regno, strerror (errno)); | |
5527 | } | |
5528 | ||
5529 | if (the_low_target.supply_ptrace_register) | |
5530 | the_low_target.supply_ptrace_register (regcache, regno, buf); | |
5531 | else | |
5532 | supply_register (regcache, regno, buf); | |
5533 | } | |
5534 | ||
5535 | /* Store one register. */ | |
5536 | static void | |
5537 | store_register (const struct usrregs_info *usrregs, | |
5538 | struct regcache *regcache, int regno) | |
5539 | { | |
5540 | CORE_ADDR regaddr; | |
5541 | int i, size; | |
5542 | char *buf; | |
5543 | int pid; | |
5544 | ||
5545 | if (regno >= usrregs->num_regs) | |
5546 | return; | |
5547 | if ((*the_low_target.cannot_store_register) (regno)) | |
5548 | return; | |
5549 | ||
5550 | regaddr = register_addr (usrregs, regno); | |
5551 | if (regaddr == -1) | |
5552 | return; | |
5553 | ||
5554 | size = ((register_size (regcache->tdesc, regno) | |
5555 | + sizeof (PTRACE_XFER_TYPE) - 1) | |
5556 | & -sizeof (PTRACE_XFER_TYPE)); | |
5557 | buf = (char *) alloca (size); | |
5558 | memset (buf, 0, size); | |
5559 | ||
5560 | if (the_low_target.collect_ptrace_register) | |
5561 | the_low_target.collect_ptrace_register (regcache, regno, buf); | |
5562 | else | |
5563 | collect_register (regcache, regno, buf); | |
5564 | ||
5565 | pid = lwpid_of (current_thread); | |
5566 | for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE)) | |
5567 | { | |
5568 | errno = 0; | |
5569 | ptrace (PTRACE_POKEUSER, pid, | |
5570 | /* Coerce to a uintptr_t first to avoid potential gcc warning | |
5571 | about coercing an 8 byte integer to a 4 byte pointer. */ | |
5572 | (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, | |
5573 | (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i)); | |
5574 | if (errno != 0) | |
5575 | { | |
5576 | /* At this point, ESRCH should mean the process is | |
5577 | already gone, in which case we simply ignore attempts | |
5578 | to change its registers. See also the related | |
5579 | comment in linux_resume_one_lwp. */ | |
5580 | if (errno == ESRCH) | |
5581 | return; | |
5582 | ||
5583 | if ((*the_low_target.cannot_store_register) (regno) == 0) | |
5584 | error ("writing register %d: %s", regno, strerror (errno)); | |
5585 | } | |
5586 | regaddr += sizeof (PTRACE_XFER_TYPE); | |
5587 | } | |
5588 | } | |
5589 | ||
5590 | /* Fetch all registers, or just one, from the child process. | |
5591 | If REGNO is -1, do this for all registers, skipping any that are | |
5592 | assumed to have been retrieved by regsets_fetch_inferior_registers, | |
5593 | unless ALL is non-zero. | |
5594 | Otherwise, REGNO specifies which register (so we can save time). */ | |
5595 | static void | |
5596 | usr_fetch_inferior_registers (const struct regs_info *regs_info, | |
5597 | struct regcache *regcache, int regno, int all) | |
5598 | { | |
5599 | struct usrregs_info *usr = regs_info->usrregs; | |
5600 | ||
5601 | if (regno == -1) | |
5602 | { | |
5603 | for (regno = 0; regno < usr->num_regs; regno++) | |
5604 | if (all || !linux_register_in_regsets (regs_info, regno)) | |
5605 | fetch_register (usr, regcache, regno); | |
5606 | } | |
5607 | else | |
5608 | fetch_register (usr, regcache, regno); | |
5609 | } | |
5610 | ||
5611 | /* Store our register values back into the inferior. | |
5612 | If REGNO is -1, do this for all registers, skipping any that are | |
5613 | assumed to have been saved by regsets_store_inferior_registers, | |
5614 | unless ALL is non-zero. | |
5615 | Otherwise, REGNO specifies which register (so we can save time). */ | |
5616 | static void | |
5617 | usr_store_inferior_registers (const struct regs_info *regs_info, | |
5618 | struct regcache *regcache, int regno, int all) | |
5619 | { | |
5620 | struct usrregs_info *usr = regs_info->usrregs; | |
5621 | ||
5622 | if (regno == -1) | |
5623 | { | |
5624 | for (regno = 0; regno < usr->num_regs; regno++) | |
5625 | if (all || !linux_register_in_regsets (regs_info, regno)) | |
5626 | store_register (usr, regcache, regno); | |
5627 | } | |
5628 | else | |
5629 | store_register (usr, regcache, regno); | |
5630 | } | |
5631 | ||
5632 | #else /* !HAVE_LINUX_USRREGS */ | |
5633 | ||
5634 | #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0) | |
5635 | #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0) | |
5636 | ||
5637 | #endif | |
5638 | ||
5639 | ||
5640 | static void | |
5641 | linux_fetch_registers (struct regcache *regcache, int regno) | |
5642 | { | |
5643 | int use_regsets; | |
5644 | int all = 0; | |
5645 | const struct regs_info *regs_info = (*the_low_target.regs_info) (); | |
5646 | ||
5647 | if (regno == -1) | |
5648 | { | |
5649 | if (the_low_target.fetch_register != NULL | |
5650 | && regs_info->usrregs != NULL) | |
5651 | for (regno = 0; regno < regs_info->usrregs->num_regs; regno++) | |
5652 | (*the_low_target.fetch_register) (regcache, regno); | |
5653 | ||
5654 | all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache); | |
5655 | if (regs_info->usrregs != NULL) | |
5656 | usr_fetch_inferior_registers (regs_info, regcache, -1, all); | |
5657 | } | |
5658 | else | |
5659 | { | |
5660 | if (the_low_target.fetch_register != NULL | |
5661 | && (*the_low_target.fetch_register) (regcache, regno)) | |
5662 | return; | |
5663 | ||
5664 | use_regsets = linux_register_in_regsets (regs_info, regno); | |
5665 | if (use_regsets) | |
5666 | all = regsets_fetch_inferior_registers (regs_info->regsets_info, | |
5667 | regcache); | |
5668 | if ((!use_regsets || all) && regs_info->usrregs != NULL) | |
5669 | usr_fetch_inferior_registers (regs_info, regcache, regno, 1); | |
5670 | } | |
5671 | } | |
5672 | ||
5673 | static void | |
5674 | linux_store_registers (struct regcache *regcache, int regno) | |
5675 | { | |
5676 | int use_regsets; | |
5677 | int all = 0; | |
5678 | const struct regs_info *regs_info = (*the_low_target.regs_info) (); | |
5679 | ||
5680 | if (regno == -1) | |
5681 | { | |
5682 | all = regsets_store_inferior_registers (regs_info->regsets_info, | |
5683 | regcache); | |
5684 | if (regs_info->usrregs != NULL) | |
5685 | usr_store_inferior_registers (regs_info, regcache, regno, all); | |
5686 | } | |
5687 | else | |
5688 | { | |
5689 | use_regsets = linux_register_in_regsets (regs_info, regno); | |
5690 | if (use_regsets) | |
5691 | all = regsets_store_inferior_registers (regs_info->regsets_info, | |
5692 | regcache); | |
5693 | if ((!use_regsets || all) && regs_info->usrregs != NULL) | |
5694 | usr_store_inferior_registers (regs_info, regcache, regno, 1); | |
5695 | } | |
5696 | } | |
5697 | ||
5698 | ||
5699 | /* Copy LEN bytes from inferior's memory starting at MEMADDR | |
5700 | to debugger memory starting at MYADDR. */ | |
5701 | ||
5702 | static int | |
5703 | linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len) | |
5704 | { | |
5705 | int pid = lwpid_of (current_thread); | |
5706 | register PTRACE_XFER_TYPE *buffer; | |
5707 | register CORE_ADDR addr; | |
5708 | register int count; | |
5709 | char filename[64]; | |
5710 | register int i; | |
5711 | int ret; | |
5712 | int fd; | |
5713 | ||
5714 | /* Try using /proc. Don't bother for one word. */ | |
5715 | if (len >= 3 * sizeof (long)) | |
5716 | { | |
5717 | int bytes; | |
5718 | ||
5719 | /* We could keep this file open and cache it - possibly one per | |
5720 | thread. That requires some juggling, but is even faster. */ | |
5721 | sprintf (filename, "/proc/%d/mem", pid); | |
5722 | fd = open (filename, O_RDONLY | O_LARGEFILE); | |
5723 | if (fd == -1) | |
5724 | goto no_proc; | |
5725 | ||
5726 | /* If pread64 is available, use it. It's faster if the kernel | |
5727 | supports it (only one syscall), and it's 64-bit safe even on | |
5728 | 32-bit platforms (for instance, SPARC debugging a SPARC64 | |
5729 | application). */ | |
5730 | #ifdef HAVE_PREAD64 | |
5731 | bytes = pread64 (fd, myaddr, len, memaddr); | |
5732 | #else | |
5733 | bytes = -1; | |
5734 | if (lseek (fd, memaddr, SEEK_SET) != -1) | |
5735 | bytes = read (fd, myaddr, len); | |
5736 | #endif | |
5737 | ||
5738 | close (fd); | |
5739 | if (bytes == len) | |
5740 | return 0; | |
5741 | ||
5742 | /* Some data was read, we'll try to get the rest with ptrace. */ | |
5743 | if (bytes > 0) | |
5744 | { | |
5745 | memaddr += bytes; | |
5746 | myaddr += bytes; | |
5747 | len -= bytes; | |
5748 | } | |
5749 | } | |
5750 | ||
5751 | no_proc: | |
5752 | /* Round starting address down to longword boundary. */ | |
5753 | addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
5754 | /* Round ending address up; get number of longwords that makes. */ | |
5755 | count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) | |
5756 | / sizeof (PTRACE_XFER_TYPE)); | |
5757 | /* Allocate buffer of that many longwords. */ | |
5758 | buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count); | |
5759 | ||
5760 | /* Read all the longwords */ | |
5761 | errno = 0; | |
5762 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
5763 | { | |
5764 | /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning | |
5765 | about coercing an 8 byte integer to a 4 byte pointer. */ | |
5766 | buffer[i] = ptrace (PTRACE_PEEKTEXT, pid, | |
5767 | (PTRACE_TYPE_ARG3) (uintptr_t) addr, | |
5768 | (PTRACE_TYPE_ARG4) 0); | |
5769 | if (errno) | |
5770 | break; | |
5771 | } | |
5772 | ret = errno; | |
5773 | ||
5774 | /* Copy appropriate bytes out of the buffer. */ | |
5775 | if (i > 0) | |
5776 | { | |
5777 | i *= sizeof (PTRACE_XFER_TYPE); | |
5778 | i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1); | |
5779 | memcpy (myaddr, | |
5780 | (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), | |
5781 | i < len ? i : len); | |
5782 | } | |
5783 | ||
5784 | return ret; | |
5785 | } | |
5786 | ||
5787 | /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's | |
5788 | memory at MEMADDR. On failure (cannot write to the inferior) | |
5789 | returns the value of errno. Always succeeds if LEN is zero. */ | |
5790 | ||
5791 | static int | |
5792 | linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len) | |
5793 | { | |
5794 | register int i; | |
5795 | /* Round starting address down to longword boundary. */ | |
5796 | register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE); | |
5797 | /* Round ending address up; get number of longwords that makes. */ | |
5798 | register int count | |
5799 | = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) | |
5800 | / sizeof (PTRACE_XFER_TYPE); | |
5801 | ||
5802 | /* Allocate buffer of that many longwords. */ | |
5803 | register PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count); | |
5804 | ||
5805 | int pid = lwpid_of (current_thread); | |
5806 | ||
5807 | if (len == 0) | |
5808 | { | |
5809 | /* Zero length write always succeeds. */ | |
5810 | return 0; | |
5811 | } | |
5812 | ||
5813 | if (debug_threads) | |
5814 | { | |
5815 | /* Dump up to four bytes. */ | |
5816 | char str[4 * 2 + 1]; | |
5817 | char *p = str; | |
5818 | int dump = len < 4 ? len : 4; | |
5819 | ||
5820 | for (i = 0; i < dump; i++) | |
5821 | { | |
5822 | sprintf (p, "%02x", myaddr[i]); | |
5823 | p += 2; | |
5824 | } | |
5825 | *p = '\0'; | |
5826 | ||
5827 | debug_printf ("Writing %s to 0x%08lx in process %d\n", | |
5828 | str, (long) memaddr, pid); | |
5829 | } | |
5830 | ||
5831 | /* Fill start and end extra bytes of buffer with existing memory data. */ | |
5832 | ||
5833 | errno = 0; | |
5834 | /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning | |
5835 | about coercing an 8 byte integer to a 4 byte pointer. */ | |
5836 | buffer[0] = ptrace (PTRACE_PEEKTEXT, pid, | |
5837 | (PTRACE_TYPE_ARG3) (uintptr_t) addr, | |
5838 | (PTRACE_TYPE_ARG4) 0); | |
5839 | if (errno) | |
5840 | return errno; | |
5841 | ||
5842 | if (count > 1) | |
5843 | { | |
5844 | errno = 0; | |
5845 | buffer[count - 1] | |
5846 | = ptrace (PTRACE_PEEKTEXT, pid, | |
5847 | /* Coerce to a uintptr_t first to avoid potential gcc warning | |
5848 | about coercing an 8 byte integer to a 4 byte pointer. */ | |
5849 | (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1) | |
5850 | * sizeof (PTRACE_XFER_TYPE)), | |
5851 | (PTRACE_TYPE_ARG4) 0); | |
5852 | if (errno) | |
5853 | return errno; | |
5854 | } | |
5855 | ||
5856 | /* Copy data to be written over corresponding part of buffer. */ | |
5857 | ||
5858 | memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), | |
5859 | myaddr, len); | |
5860 | ||
5861 | /* Write the entire buffer. */ | |
5862 | ||
5863 | for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE)) | |
5864 | { | |
5865 | errno = 0; | |
5866 | ptrace (PTRACE_POKETEXT, pid, | |
5867 | /* Coerce to a uintptr_t first to avoid potential gcc warning | |
5868 | about coercing an 8 byte integer to a 4 byte pointer. */ | |
5869 | (PTRACE_TYPE_ARG3) (uintptr_t) addr, | |
5870 | (PTRACE_TYPE_ARG4) buffer[i]); | |
5871 | if (errno) | |
5872 | return errno; | |
5873 | } | |
5874 | ||
5875 | return 0; | |
5876 | } | |
5877 | ||
5878 | static void | |
5879 | linux_look_up_symbols (void) | |
5880 | { | |
5881 | #ifdef USE_THREAD_DB | |
5882 | struct process_info *proc = current_process (); | |
5883 | ||
5884 | if (proc->priv->thread_db != NULL) | |
5885 | return; | |
5886 | ||
5887 | thread_db_init (); | |
5888 | #endif | |
5889 | } | |
5890 | ||
5891 | static void | |
5892 | linux_request_interrupt (void) | |
5893 | { | |
5894 | extern unsigned long signal_pid; | |
5895 | ||
5896 | /* Send a SIGINT to the process group. This acts just like the user | |
5897 | typed a ^C on the controlling terminal. */ | |
5898 | kill (-signal_pid, SIGINT); | |
5899 | } | |
5900 | ||
5901 | /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET | |
5902 | to debugger memory starting at MYADDR. */ | |
5903 | ||
5904 | static int | |
5905 | linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len) | |
5906 | { | |
5907 | char filename[PATH_MAX]; | |
5908 | int fd, n; | |
5909 | int pid = lwpid_of (current_thread); | |
5910 | ||
5911 | xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid); | |
5912 | ||
5913 | fd = open (filename, O_RDONLY); | |
5914 | if (fd < 0) | |
5915 | return -1; | |
5916 | ||
5917 | if (offset != (CORE_ADDR) 0 | |
5918 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
5919 | n = -1; | |
5920 | else | |
5921 | n = read (fd, myaddr, len); | |
5922 | ||
5923 | close (fd); | |
5924 | ||
5925 | return n; | |
5926 | } | |
5927 | ||
5928 | /* These breakpoint and watchpoint related wrapper functions simply | |
5929 | pass on the function call if the target has registered a | |
5930 | corresponding function. */ | |
5931 | ||
5932 | static int | |
5933 | linux_supports_z_point_type (char z_type) | |
5934 | { | |
5935 | return (the_low_target.supports_z_point_type != NULL | |
5936 | && the_low_target.supports_z_point_type (z_type)); | |
5937 | } | |
5938 | ||
5939 | static int | |
5940 | linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr, | |
5941 | int size, struct raw_breakpoint *bp) | |
5942 | { | |
5943 | if (type == raw_bkpt_type_sw) | |
5944 | return insert_memory_breakpoint (bp); | |
5945 | else if (the_low_target.insert_point != NULL) | |
5946 | return the_low_target.insert_point (type, addr, size, bp); | |
5947 | else | |
5948 | /* Unsupported (see target.h). */ | |
5949 | return 1; | |
5950 | } | |
5951 | ||
5952 | static int | |
5953 | linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr, | |
5954 | int size, struct raw_breakpoint *bp) | |
5955 | { | |
5956 | if (type == raw_bkpt_type_sw) | |
5957 | return remove_memory_breakpoint (bp); | |
5958 | else if (the_low_target.remove_point != NULL) | |
5959 | return the_low_target.remove_point (type, addr, size, bp); | |
5960 | else | |
5961 | /* Unsupported (see target.h). */ | |
5962 | return 1; | |
5963 | } | |
5964 | ||
5965 | /* Implement the to_stopped_by_sw_breakpoint target_ops | |
5966 | method. */ | |
5967 | ||
5968 | static int | |
5969 | linux_stopped_by_sw_breakpoint (void) | |
5970 | { | |
5971 | struct lwp_info *lwp = get_thread_lwp (current_thread); | |
5972 | ||
5973 | return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT); | |
5974 | } | |
5975 | ||
5976 | /* Implement the to_supports_stopped_by_sw_breakpoint target_ops | |
5977 | method. */ | |
5978 | ||
5979 | static int | |
5980 | linux_supports_stopped_by_sw_breakpoint (void) | |
5981 | { | |
5982 | return USE_SIGTRAP_SIGINFO; | |
5983 | } | |
5984 | ||
5985 | /* Implement the to_stopped_by_hw_breakpoint target_ops | |
5986 | method. */ | |
5987 | ||
5988 | static int | |
5989 | linux_stopped_by_hw_breakpoint (void) | |
5990 | { | |
5991 | struct lwp_info *lwp = get_thread_lwp (current_thread); | |
5992 | ||
5993 | return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT); | |
5994 | } | |
5995 | ||
5996 | /* Implement the to_supports_stopped_by_hw_breakpoint target_ops | |
5997 | method. */ | |
5998 | ||
5999 | static int | |
6000 | linux_supports_stopped_by_hw_breakpoint (void) | |
6001 | { | |
6002 | return USE_SIGTRAP_SIGINFO; | |
6003 | } | |
6004 | ||
6005 | /* Implement the supports_hardware_single_step target_ops method. */ | |
6006 | ||
6007 | static int | |
6008 | linux_supports_hardware_single_step (void) | |
6009 | { | |
6010 | return can_hardware_single_step (); | |
6011 | } | |
6012 | ||
6013 | static int | |
6014 | linux_supports_software_single_step (void) | |
6015 | { | |
6016 | return can_software_single_step (); | |
6017 | } | |
6018 | ||
6019 | static int | |
6020 | linux_stopped_by_watchpoint (void) | |
6021 | { | |
6022 | struct lwp_info *lwp = get_thread_lwp (current_thread); | |
6023 | ||
6024 | return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; | |
6025 | } | |
6026 | ||
6027 | static CORE_ADDR | |
6028 | linux_stopped_data_address (void) | |
6029 | { | |
6030 | struct lwp_info *lwp = get_thread_lwp (current_thread); | |
6031 | ||
6032 | return lwp->stopped_data_address; | |
6033 | } | |
6034 | ||
6035 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) \ | |
6036 | && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \ | |
6037 | && defined(PT_TEXT_END_ADDR) | |
6038 | ||
6039 | /* This is only used for targets that define PT_TEXT_ADDR, | |
6040 | PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly | |
6041 | the target has different ways of acquiring this information, like | |
6042 | loadmaps. */ | |
6043 | ||
6044 | /* Under uClinux, programs are loaded at non-zero offsets, which we need | |
6045 | to tell gdb about. */ | |
6046 | ||
6047 | static int | |
6048 | linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p) | |
6049 | { | |
6050 | unsigned long text, text_end, data; | |
6051 | int pid = lwpid_of (current_thread); | |
6052 | ||
6053 | errno = 0; | |
6054 | ||
6055 | text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR, | |
6056 | (PTRACE_TYPE_ARG4) 0); | |
6057 | text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR, | |
6058 | (PTRACE_TYPE_ARG4) 0); | |
6059 | data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR, | |
6060 | (PTRACE_TYPE_ARG4) 0); | |
6061 | ||
6062 | if (errno == 0) | |
6063 | { | |
6064 | /* Both text and data offsets produced at compile-time (and so | |
6065 | used by gdb) are relative to the beginning of the program, | |
6066 | with the data segment immediately following the text segment. | |
6067 | However, the actual runtime layout in memory may put the data | |
6068 | somewhere else, so when we send gdb a data base-address, we | |
6069 | use the real data base address and subtract the compile-time | |
6070 | data base-address from it (which is just the length of the | |
6071 | text segment). BSS immediately follows data in both | |
6072 | cases. */ | |
6073 | *text_p = text; | |
6074 | *data_p = data - (text_end - text); | |
6075 | ||
6076 | return 1; | |
6077 | } | |
6078 | return 0; | |
6079 | } | |
6080 | #endif | |
6081 | ||
6082 | static int | |
6083 | linux_qxfer_osdata (const char *annex, | |
6084 | unsigned char *readbuf, unsigned const char *writebuf, | |
6085 | CORE_ADDR offset, int len) | |
6086 | { | |
6087 | return linux_common_xfer_osdata (annex, readbuf, offset, len); | |
6088 | } | |
6089 | ||
6090 | /* Convert a native/host siginfo object, into/from the siginfo in the | |
6091 | layout of the inferiors' architecture. */ | |
6092 | ||
6093 | static void | |
6094 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) | |
6095 | { | |
6096 | int done = 0; | |
6097 | ||
6098 | if (the_low_target.siginfo_fixup != NULL) | |
6099 | done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction); | |
6100 | ||
6101 | /* If there was no callback, or the callback didn't do anything, | |
6102 | then just do a straight memcpy. */ | |
6103 | if (!done) | |
6104 | { | |
6105 | if (direction == 1) | |
6106 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); | |
6107 | else | |
6108 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); | |
6109 | } | |
6110 | } | |
6111 | ||
6112 | static int | |
6113 | linux_xfer_siginfo (const char *annex, unsigned char *readbuf, | |
6114 | unsigned const char *writebuf, CORE_ADDR offset, int len) | |
6115 | { | |
6116 | int pid; | |
6117 | siginfo_t siginfo; | |
6118 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
6119 | ||
6120 | if (current_thread == NULL) | |
6121 | return -1; | |
6122 | ||
6123 | pid = lwpid_of (current_thread); | |
6124 | ||
6125 | if (debug_threads) | |
6126 | debug_printf ("%s siginfo for lwp %d.\n", | |
6127 | readbuf != NULL ? "Reading" : "Writing", | |
6128 | pid); | |
6129 | ||
6130 | if (offset >= sizeof (siginfo)) | |
6131 | return -1; | |
6132 | ||
6133 | if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0) | |
6134 | return -1; | |
6135 | ||
6136 | /* When GDBSERVER is built as a 64-bit application, ptrace writes into | |
6137 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
6138 | inferior with a 64-bit GDBSERVER should look the same as debugging it | |
6139 | with a 32-bit GDBSERVER, we need to convert it. */ | |
6140 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
6141 | ||
6142 | if (offset + len > sizeof (siginfo)) | |
6143 | len = sizeof (siginfo) - offset; | |
6144 | ||
6145 | if (readbuf != NULL) | |
6146 | memcpy (readbuf, inf_siginfo + offset, len); | |
6147 | else | |
6148 | { | |
6149 | memcpy (inf_siginfo + offset, writebuf, len); | |
6150 | ||
6151 | /* Convert back to ptrace layout before flushing it out. */ | |
6152 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
6153 | ||
6154 | if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0) | |
6155 | return -1; | |
6156 | } | |
6157 | ||
6158 | return len; | |
6159 | } | |
6160 | ||
6161 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, | |
6162 | so we notice when children change state; as the handler for the | |
6163 | sigsuspend in my_waitpid. */ | |
6164 | ||
6165 | static void | |
6166 | sigchld_handler (int signo) | |
6167 | { | |
6168 | int old_errno = errno; | |
6169 | ||
6170 | if (debug_threads) | |
6171 | { | |
6172 | do | |
6173 | { | |
6174 | /* fprintf is not async-signal-safe, so call write | |
6175 | directly. */ | |
6176 | if (write (2, "sigchld_handler\n", | |
6177 | sizeof ("sigchld_handler\n") - 1) < 0) | |
6178 | break; /* just ignore */ | |
6179 | } while (0); | |
6180 | } | |
6181 | ||
6182 | if (target_is_async_p ()) | |
6183 | async_file_mark (); /* trigger a linux_wait */ | |
6184 | ||
6185 | errno = old_errno; | |
6186 | } | |
6187 | ||
6188 | static int | |
6189 | linux_supports_non_stop (void) | |
6190 | { | |
6191 | return 1; | |
6192 | } | |
6193 | ||
6194 | static int | |
6195 | linux_async (int enable) | |
6196 | { | |
6197 | int previous = target_is_async_p (); | |
6198 | ||
6199 | if (debug_threads) | |
6200 | debug_printf ("linux_async (%d), previous=%d\n", | |
6201 | enable, previous); | |
6202 | ||
6203 | if (previous != enable) | |
6204 | { | |
6205 | sigset_t mask; | |
6206 | sigemptyset (&mask); | |
6207 | sigaddset (&mask, SIGCHLD); | |
6208 | ||
6209 | sigprocmask (SIG_BLOCK, &mask, NULL); | |
6210 | ||
6211 | if (enable) | |
6212 | { | |
6213 | if (pipe (linux_event_pipe) == -1) | |
6214 | { | |
6215 | linux_event_pipe[0] = -1; | |
6216 | linux_event_pipe[1] = -1; | |
6217 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
6218 | ||
6219 | warning ("creating event pipe failed."); | |
6220 | return previous; | |
6221 | } | |
6222 | ||
6223 | fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK); | |
6224 | fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK); | |
6225 | ||
6226 | /* Register the event loop handler. */ | |
6227 | add_file_handler (linux_event_pipe[0], | |
6228 | handle_target_event, NULL); | |
6229 | ||
6230 | /* Always trigger a linux_wait. */ | |
6231 | async_file_mark (); | |
6232 | } | |
6233 | else | |
6234 | { | |
6235 | delete_file_handler (linux_event_pipe[0]); | |
6236 | ||
6237 | close (linux_event_pipe[0]); | |
6238 | close (linux_event_pipe[1]); | |
6239 | linux_event_pipe[0] = -1; | |
6240 | linux_event_pipe[1] = -1; | |
6241 | } | |
6242 | ||
6243 | sigprocmask (SIG_UNBLOCK, &mask, NULL); | |
6244 | } | |
6245 | ||
6246 | return previous; | |
6247 | } | |
6248 | ||
6249 | static int | |
6250 | linux_start_non_stop (int nonstop) | |
6251 | { | |
6252 | /* Register or unregister from event-loop accordingly. */ | |
6253 | linux_async (nonstop); | |
6254 | ||
6255 | if (target_is_async_p () != (nonstop != 0)) | |
6256 | return -1; | |
6257 | ||
6258 | return 0; | |
6259 | } | |
6260 | ||
6261 | static int | |
6262 | linux_supports_multi_process (void) | |
6263 | { | |
6264 | return 1; | |
6265 | } | |
6266 | ||
6267 | /* Check if fork events are supported. */ | |
6268 | ||
6269 | static int | |
6270 | linux_supports_fork_events (void) | |
6271 | { | |
6272 | return linux_supports_tracefork (); | |
6273 | } | |
6274 | ||
6275 | /* Check if vfork events are supported. */ | |
6276 | ||
6277 | static int | |
6278 | linux_supports_vfork_events (void) | |
6279 | { | |
6280 | return linux_supports_tracefork (); | |
6281 | } | |
6282 | ||
6283 | /* Check if exec events are supported. */ | |
6284 | ||
6285 | static int | |
6286 | linux_supports_exec_events (void) | |
6287 | { | |
6288 | return linux_supports_traceexec (); | |
6289 | } | |
6290 | ||
6291 | /* Callback for 'find_inferior'. Set the (possibly changed) ptrace | |
6292 | options for the specified lwp. */ | |
6293 | ||
6294 | static int | |
6295 | reset_lwp_ptrace_options_callback (struct inferior_list_entry *entry, | |
6296 | void *args) | |
6297 | { | |
6298 | struct thread_info *thread = (struct thread_info *) entry; | |
6299 | struct lwp_info *lwp = get_thread_lwp (thread); | |
6300 | ||
6301 | if (!lwp->stopped) | |
6302 | { | |
6303 | /* Stop the lwp so we can modify its ptrace options. */ | |
6304 | lwp->must_set_ptrace_flags = 1; | |
6305 | linux_stop_lwp (lwp); | |
6306 | } | |
6307 | else | |
6308 | { | |
6309 | /* Already stopped; go ahead and set the ptrace options. */ | |
6310 | struct process_info *proc = find_process_pid (pid_of (thread)); | |
6311 | int options = linux_low_ptrace_options (proc->attached); | |
6312 | ||
6313 | linux_enable_event_reporting (lwpid_of (thread), options); | |
6314 | lwp->must_set_ptrace_flags = 0; | |
6315 | } | |
6316 | ||
6317 | return 0; | |
6318 | } | |
6319 | ||
6320 | /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the | |
6321 | ptrace flags for all inferiors. This is in case the new GDB connection | |
6322 | doesn't support the same set of events that the previous one did. */ | |
6323 | ||
6324 | static void | |
6325 | linux_handle_new_gdb_connection (void) | |
6326 | { | |
6327 | pid_t pid; | |
6328 | ||
6329 | /* Request that all the lwps reset their ptrace options. */ | |
6330 | find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid); | |
6331 | } | |
6332 | ||
6333 | static int | |
6334 | linux_supports_disable_randomization (void) | |
6335 | { | |
6336 | #ifdef HAVE_PERSONALITY | |
6337 | return 1; | |
6338 | #else | |
6339 | return 0; | |
6340 | #endif | |
6341 | } | |
6342 | ||
6343 | static int | |
6344 | linux_supports_agent (void) | |
6345 | { | |
6346 | return 1; | |
6347 | } | |
6348 | ||
6349 | static int | |
6350 | linux_supports_range_stepping (void) | |
6351 | { | |
6352 | if (*the_low_target.supports_range_stepping == NULL) | |
6353 | return 0; | |
6354 | ||
6355 | return (*the_low_target.supports_range_stepping) (); | |
6356 | } | |
6357 | ||
6358 | /* Enumerate spufs IDs for process PID. */ | |
6359 | static int | |
6360 | spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len) | |
6361 | { | |
6362 | int pos = 0; | |
6363 | int written = 0; | |
6364 | char path[128]; | |
6365 | DIR *dir; | |
6366 | struct dirent *entry; | |
6367 | ||
6368 | sprintf (path, "/proc/%ld/fd", pid); | |
6369 | dir = opendir (path); | |
6370 | if (!dir) | |
6371 | return -1; | |
6372 | ||
6373 | rewinddir (dir); | |
6374 | while ((entry = readdir (dir)) != NULL) | |
6375 | { | |
6376 | struct stat st; | |
6377 | struct statfs stfs; | |
6378 | int fd; | |
6379 | ||
6380 | fd = atoi (entry->d_name); | |
6381 | if (!fd) | |
6382 | continue; | |
6383 | ||
6384 | sprintf (path, "/proc/%ld/fd/%d", pid, fd); | |
6385 | if (stat (path, &st) != 0) | |
6386 | continue; | |
6387 | if (!S_ISDIR (st.st_mode)) | |
6388 | continue; | |
6389 | ||
6390 | if (statfs (path, &stfs) != 0) | |
6391 | continue; | |
6392 | if (stfs.f_type != SPUFS_MAGIC) | |
6393 | continue; | |
6394 | ||
6395 | if (pos >= offset && pos + 4 <= offset + len) | |
6396 | { | |
6397 | *(unsigned int *)(buf + pos - offset) = fd; | |
6398 | written += 4; | |
6399 | } | |
6400 | pos += 4; | |
6401 | } | |
6402 | ||
6403 | closedir (dir); | |
6404 | return written; | |
6405 | } | |
6406 | ||
6407 | /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU | |
6408 | object type, using the /proc file system. */ | |
6409 | static int | |
6410 | linux_qxfer_spu (const char *annex, unsigned char *readbuf, | |
6411 | unsigned const char *writebuf, | |
6412 | CORE_ADDR offset, int len) | |
6413 | { | |
6414 | long pid = lwpid_of (current_thread); | |
6415 | char buf[128]; | |
6416 | int fd = 0; | |
6417 | int ret = 0; | |
6418 | ||
6419 | if (!writebuf && !readbuf) | |
6420 | return -1; | |
6421 | ||
6422 | if (!*annex) | |
6423 | { | |
6424 | if (!readbuf) | |
6425 | return -1; | |
6426 | else | |
6427 | return spu_enumerate_spu_ids (pid, readbuf, offset, len); | |
6428 | } | |
6429 | ||
6430 | sprintf (buf, "/proc/%ld/fd/%s", pid, annex); | |
6431 | fd = open (buf, writebuf? O_WRONLY : O_RDONLY); | |
6432 | if (fd <= 0) | |
6433 | return -1; | |
6434 | ||
6435 | if (offset != 0 | |
6436 | && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset) | |
6437 | { | |
6438 | close (fd); | |
6439 | return 0; | |
6440 | } | |
6441 | ||
6442 | if (writebuf) | |
6443 | ret = write (fd, writebuf, (size_t) len); | |
6444 | else | |
6445 | ret = read (fd, readbuf, (size_t) len); | |
6446 | ||
6447 | close (fd); | |
6448 | return ret; | |
6449 | } | |
6450 | ||
6451 | #if defined PT_GETDSBT || defined PTRACE_GETFDPIC | |
6452 | struct target_loadseg | |
6453 | { | |
6454 | /* Core address to which the segment is mapped. */ | |
6455 | Elf32_Addr addr; | |
6456 | /* VMA recorded in the program header. */ | |
6457 | Elf32_Addr p_vaddr; | |
6458 | /* Size of this segment in memory. */ | |
6459 | Elf32_Word p_memsz; | |
6460 | }; | |
6461 | ||
6462 | # if defined PT_GETDSBT | |
6463 | struct target_loadmap | |
6464 | { | |
6465 | /* Protocol version number, must be zero. */ | |
6466 | Elf32_Word version; | |
6467 | /* Pointer to the DSBT table, its size, and the DSBT index. */ | |
6468 | unsigned *dsbt_table; | |
6469 | unsigned dsbt_size, dsbt_index; | |
6470 | /* Number of segments in this map. */ | |
6471 | Elf32_Word nsegs; | |
6472 | /* The actual memory map. */ | |
6473 | struct target_loadseg segs[/*nsegs*/]; | |
6474 | }; | |
6475 | # define LINUX_LOADMAP PT_GETDSBT | |
6476 | # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC | |
6477 | # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP | |
6478 | # else | |
6479 | struct target_loadmap | |
6480 | { | |
6481 | /* Protocol version number, must be zero. */ | |
6482 | Elf32_Half version; | |
6483 | /* Number of segments in this map. */ | |
6484 | Elf32_Half nsegs; | |
6485 | /* The actual memory map. */ | |
6486 | struct target_loadseg segs[/*nsegs*/]; | |
6487 | }; | |
6488 | # define LINUX_LOADMAP PTRACE_GETFDPIC | |
6489 | # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC | |
6490 | # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP | |
6491 | # endif | |
6492 | ||
6493 | static int | |
6494 | linux_read_loadmap (const char *annex, CORE_ADDR offset, | |
6495 | unsigned char *myaddr, unsigned int len) | |
6496 | { | |
6497 | int pid = lwpid_of (current_thread); | |
6498 | int addr = -1; | |
6499 | struct target_loadmap *data = NULL; | |
6500 | unsigned int actual_length, copy_length; | |
6501 | ||
6502 | if (strcmp (annex, "exec") == 0) | |
6503 | addr = (int) LINUX_LOADMAP_EXEC; | |
6504 | else if (strcmp (annex, "interp") == 0) | |
6505 | addr = (int) LINUX_LOADMAP_INTERP; | |
6506 | else | |
6507 | return -1; | |
6508 | ||
6509 | if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0) | |
6510 | return -1; | |
6511 | ||
6512 | if (data == NULL) | |
6513 | return -1; | |
6514 | ||
6515 | actual_length = sizeof (struct target_loadmap) | |
6516 | + sizeof (struct target_loadseg) * data->nsegs; | |
6517 | ||
6518 | if (offset < 0 || offset > actual_length) | |
6519 | return -1; | |
6520 | ||
6521 | copy_length = actual_length - offset < len ? actual_length - offset : len; | |
6522 | memcpy (myaddr, (char *) data + offset, copy_length); | |
6523 | return copy_length; | |
6524 | } | |
6525 | #else | |
6526 | # define linux_read_loadmap NULL | |
6527 | #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */ | |
6528 | ||
6529 | static void | |
6530 | linux_process_qsupported (char **features, int count) | |
6531 | { | |
6532 | if (the_low_target.process_qsupported != NULL) | |
6533 | the_low_target.process_qsupported (features, count); | |
6534 | } | |
6535 | ||
6536 | static int | |
6537 | linux_supports_catch_syscall (void) | |
6538 | { | |
6539 | return (the_low_target.get_syscall_trapinfo != NULL | |
6540 | && linux_supports_tracesysgood ()); | |
6541 | } | |
6542 | ||
6543 | static int | |
6544 | linux_get_ipa_tdesc_idx (void) | |
6545 | { | |
6546 | if (the_low_target.get_ipa_tdesc_idx == NULL) | |
6547 | return 0; | |
6548 | ||
6549 | return (*the_low_target.get_ipa_tdesc_idx) (); | |
6550 | } | |
6551 | ||
6552 | static int | |
6553 | linux_supports_tracepoints (void) | |
6554 | { | |
6555 | if (*the_low_target.supports_tracepoints == NULL) | |
6556 | return 0; | |
6557 | ||
6558 | return (*the_low_target.supports_tracepoints) (); | |
6559 | } | |
6560 | ||
6561 | static CORE_ADDR | |
6562 | linux_read_pc (struct regcache *regcache) | |
6563 | { | |
6564 | if (the_low_target.get_pc == NULL) | |
6565 | return 0; | |
6566 | ||
6567 | return (*the_low_target.get_pc) (regcache); | |
6568 | } | |
6569 | ||
6570 | static void | |
6571 | linux_write_pc (struct regcache *regcache, CORE_ADDR pc) | |
6572 | { | |
6573 | gdb_assert (the_low_target.set_pc != NULL); | |
6574 | ||
6575 | (*the_low_target.set_pc) (regcache, pc); | |
6576 | } | |
6577 | ||
6578 | static int | |
6579 | linux_thread_stopped (struct thread_info *thread) | |
6580 | { | |
6581 | return get_thread_lwp (thread)->stopped; | |
6582 | } | |
6583 | ||
6584 | /* This exposes stop-all-threads functionality to other modules. */ | |
6585 | ||
6586 | static void | |
6587 | linux_pause_all (int freeze) | |
6588 | { | |
6589 | stop_all_lwps (freeze, NULL); | |
6590 | } | |
6591 | ||
6592 | /* This exposes unstop-all-threads functionality to other gdbserver | |
6593 | modules. */ | |
6594 | ||
6595 | static void | |
6596 | linux_unpause_all (int unfreeze) | |
6597 | { | |
6598 | unstop_all_lwps (unfreeze, NULL); | |
6599 | } | |
6600 | ||
6601 | static int | |
6602 | linux_prepare_to_access_memory (void) | |
6603 | { | |
6604 | /* Neither ptrace nor /proc/PID/mem allow accessing memory through a | |
6605 | running LWP. */ | |
6606 | if (non_stop) | |
6607 | linux_pause_all (1); | |
6608 | return 0; | |
6609 | } | |
6610 | ||
6611 | static void | |
6612 | linux_done_accessing_memory (void) | |
6613 | { | |
6614 | /* Neither ptrace nor /proc/PID/mem allow accessing memory through a | |
6615 | running LWP. */ | |
6616 | if (non_stop) | |
6617 | linux_unpause_all (1); | |
6618 | } | |
6619 | ||
6620 | static int | |
6621 | linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr, | |
6622 | CORE_ADDR collector, | |
6623 | CORE_ADDR lockaddr, | |
6624 | ULONGEST orig_size, | |
6625 | CORE_ADDR *jump_entry, | |
6626 | CORE_ADDR *trampoline, | |
6627 | ULONGEST *trampoline_size, | |
6628 | unsigned char *jjump_pad_insn, | |
6629 | ULONGEST *jjump_pad_insn_size, | |
6630 | CORE_ADDR *adjusted_insn_addr, | |
6631 | CORE_ADDR *adjusted_insn_addr_end, | |
6632 | char *err) | |
6633 | { | |
6634 | return (*the_low_target.install_fast_tracepoint_jump_pad) | |
6635 | (tpoint, tpaddr, collector, lockaddr, orig_size, | |
6636 | jump_entry, trampoline, trampoline_size, | |
6637 | jjump_pad_insn, jjump_pad_insn_size, | |
6638 | adjusted_insn_addr, adjusted_insn_addr_end, | |
6639 | err); | |
6640 | } | |
6641 | ||
6642 | static struct emit_ops * | |
6643 | linux_emit_ops (void) | |
6644 | { | |
6645 | if (the_low_target.emit_ops != NULL) | |
6646 | return (*the_low_target.emit_ops) (); | |
6647 | else | |
6648 | return NULL; | |
6649 | } | |
6650 | ||
6651 | static int | |
6652 | linux_get_min_fast_tracepoint_insn_len (void) | |
6653 | { | |
6654 | return (*the_low_target.get_min_fast_tracepoint_insn_len) (); | |
6655 | } | |
6656 | ||
6657 | /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */ | |
6658 | ||
6659 | static int | |
6660 | get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64, | |
6661 | CORE_ADDR *phdr_memaddr, int *num_phdr) | |
6662 | { | |
6663 | char filename[PATH_MAX]; | |
6664 | int fd; | |
6665 | const int auxv_size = is_elf64 | |
6666 | ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t); | |
6667 | char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */ | |
6668 | ||
6669 | xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid); | |
6670 | ||
6671 | fd = open (filename, O_RDONLY); | |
6672 | if (fd < 0) | |
6673 | return 1; | |
6674 | ||
6675 | *phdr_memaddr = 0; | |
6676 | *num_phdr = 0; | |
6677 | while (read (fd, buf, auxv_size) == auxv_size | |
6678 | && (*phdr_memaddr == 0 || *num_phdr == 0)) | |
6679 | { | |
6680 | if (is_elf64) | |
6681 | { | |
6682 | Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf; | |
6683 | ||
6684 | switch (aux->a_type) | |
6685 | { | |
6686 | case AT_PHDR: | |
6687 | *phdr_memaddr = aux->a_un.a_val; | |
6688 | break; | |
6689 | case AT_PHNUM: | |
6690 | *num_phdr = aux->a_un.a_val; | |
6691 | break; | |
6692 | } | |
6693 | } | |
6694 | else | |
6695 | { | |
6696 | Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf; | |
6697 | ||
6698 | switch (aux->a_type) | |
6699 | { | |
6700 | case AT_PHDR: | |
6701 | *phdr_memaddr = aux->a_un.a_val; | |
6702 | break; | |
6703 | case AT_PHNUM: | |
6704 | *num_phdr = aux->a_un.a_val; | |
6705 | break; | |
6706 | } | |
6707 | } | |
6708 | } | |
6709 | ||
6710 | close (fd); | |
6711 | ||
6712 | if (*phdr_memaddr == 0 || *num_phdr == 0) | |
6713 | { | |
6714 | warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: " | |
6715 | "phdr_memaddr = %ld, phdr_num = %d", | |
6716 | (long) *phdr_memaddr, *num_phdr); | |
6717 | return 2; | |
6718 | } | |
6719 | ||
6720 | return 0; | |
6721 | } | |
6722 | ||
6723 | /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */ | |
6724 | ||
6725 | static CORE_ADDR | |
6726 | get_dynamic (const int pid, const int is_elf64) | |
6727 | { | |
6728 | CORE_ADDR phdr_memaddr, relocation; | |
6729 | int num_phdr, i; | |
6730 | unsigned char *phdr_buf; | |
6731 | const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr); | |
6732 | ||
6733 | if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr)) | |
6734 | return 0; | |
6735 | ||
6736 | gdb_assert (num_phdr < 100); /* Basic sanity check. */ | |
6737 | phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size); | |
6738 | ||
6739 | if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size)) | |
6740 | return 0; | |
6741 | ||
6742 | /* Compute relocation: it is expected to be 0 for "regular" executables, | |
6743 | non-zero for PIE ones. */ | |
6744 | relocation = -1; | |
6745 | for (i = 0; relocation == -1 && i < num_phdr; i++) | |
6746 | if (is_elf64) | |
6747 | { | |
6748 | Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size); | |
6749 | ||
6750 | if (p->p_type == PT_PHDR) | |
6751 | relocation = phdr_memaddr - p->p_vaddr; | |
6752 | } | |
6753 | else | |
6754 | { | |
6755 | Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size); | |
6756 | ||
6757 | if (p->p_type == PT_PHDR) | |
6758 | relocation = phdr_memaddr - p->p_vaddr; | |
6759 | } | |
6760 | ||
6761 | if (relocation == -1) | |
6762 | { | |
6763 | /* PT_PHDR is optional, but necessary for PIE in general. Fortunately | |
6764 | any real world executables, including PIE executables, have always | |
6765 | PT_PHDR present. PT_PHDR is not present in some shared libraries or | |
6766 | in fpc (Free Pascal 2.4) binaries but neither of those have a need for | |
6767 | or present DT_DEBUG anyway (fpc binaries are statically linked). | |
6768 | ||
6769 | Therefore if there exists DT_DEBUG there is always also PT_PHDR. | |
6770 | ||
6771 | GDB could find RELOCATION also from AT_ENTRY - e_entry. */ | |
6772 | ||
6773 | return 0; | |
6774 | } | |
6775 | ||
6776 | for (i = 0; i < num_phdr; i++) | |
6777 | { | |
6778 | if (is_elf64) | |
6779 | { | |
6780 | Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size); | |
6781 | ||
6782 | if (p->p_type == PT_DYNAMIC) | |
6783 | return p->p_vaddr + relocation; | |
6784 | } | |
6785 | else | |
6786 | { | |
6787 | Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size); | |
6788 | ||
6789 | if (p->p_type == PT_DYNAMIC) | |
6790 | return p->p_vaddr + relocation; | |
6791 | } | |
6792 | } | |
6793 | ||
6794 | return 0; | |
6795 | } | |
6796 | ||
6797 | /* Return &_r_debug in the inferior, or -1 if not present. Return value | |
6798 | can be 0 if the inferior does not yet have the library list initialized. | |
6799 | We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of | |
6800 | DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */ | |
6801 | ||
6802 | static CORE_ADDR | |
6803 | get_r_debug (const int pid, const int is_elf64) | |
6804 | { | |
6805 | CORE_ADDR dynamic_memaddr; | |
6806 | const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn); | |
6807 | unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */ | |
6808 | CORE_ADDR map = -1; | |
6809 | ||
6810 | dynamic_memaddr = get_dynamic (pid, is_elf64); | |
6811 | if (dynamic_memaddr == 0) | |
6812 | return map; | |
6813 | ||
6814 | while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0) | |
6815 | { | |
6816 | if (is_elf64) | |
6817 | { | |
6818 | Elf64_Dyn *const dyn = (Elf64_Dyn *) buf; | |
6819 | #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL | |
6820 | union | |
6821 | { | |
6822 | Elf64_Xword map; | |
6823 | unsigned char buf[sizeof (Elf64_Xword)]; | |
6824 | } | |
6825 | rld_map; | |
6826 | #endif | |
6827 | #ifdef DT_MIPS_RLD_MAP | |
6828 | if (dyn->d_tag == DT_MIPS_RLD_MAP) | |
6829 | { | |
6830 | if (linux_read_memory (dyn->d_un.d_val, | |
6831 | rld_map.buf, sizeof (rld_map.buf)) == 0) | |
6832 | return rld_map.map; | |
6833 | else | |
6834 | break; | |
6835 | } | |
6836 | #endif /* DT_MIPS_RLD_MAP */ | |
6837 | #ifdef DT_MIPS_RLD_MAP_REL | |
6838 | if (dyn->d_tag == DT_MIPS_RLD_MAP_REL) | |
6839 | { | |
6840 | if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr, | |
6841 | rld_map.buf, sizeof (rld_map.buf)) == 0) | |
6842 | return rld_map.map; | |
6843 | else | |
6844 | break; | |
6845 | } | |
6846 | #endif /* DT_MIPS_RLD_MAP_REL */ | |
6847 | ||
6848 | if (dyn->d_tag == DT_DEBUG && map == -1) | |
6849 | map = dyn->d_un.d_val; | |
6850 | ||
6851 | if (dyn->d_tag == DT_NULL) | |
6852 | break; | |
6853 | } | |
6854 | else | |
6855 | { | |
6856 | Elf32_Dyn *const dyn = (Elf32_Dyn *) buf; | |
6857 | #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL | |
6858 | union | |
6859 | { | |
6860 | Elf32_Word map; | |
6861 | unsigned char buf[sizeof (Elf32_Word)]; | |
6862 | } | |
6863 | rld_map; | |
6864 | #endif | |
6865 | #ifdef DT_MIPS_RLD_MAP | |
6866 | if (dyn->d_tag == DT_MIPS_RLD_MAP) | |
6867 | { | |
6868 | if (linux_read_memory (dyn->d_un.d_val, | |
6869 | rld_map.buf, sizeof (rld_map.buf)) == 0) | |
6870 | return rld_map.map; | |
6871 | else | |
6872 | break; | |
6873 | } | |
6874 | #endif /* DT_MIPS_RLD_MAP */ | |
6875 | #ifdef DT_MIPS_RLD_MAP_REL | |
6876 | if (dyn->d_tag == DT_MIPS_RLD_MAP_REL) | |
6877 | { | |
6878 | if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr, | |
6879 | rld_map.buf, sizeof (rld_map.buf)) == 0) | |
6880 | return rld_map.map; | |
6881 | else | |
6882 | break; | |
6883 | } | |
6884 | #endif /* DT_MIPS_RLD_MAP_REL */ | |
6885 | ||
6886 | if (dyn->d_tag == DT_DEBUG && map == -1) | |
6887 | map = dyn->d_un.d_val; | |
6888 | ||
6889 | if (dyn->d_tag == DT_NULL) | |
6890 | break; | |
6891 | } | |
6892 | ||
6893 | dynamic_memaddr += dyn_size; | |
6894 | } | |
6895 | ||
6896 | return map; | |
6897 | } | |
6898 | ||
6899 | /* Read one pointer from MEMADDR in the inferior. */ | |
6900 | ||
6901 | static int | |
6902 | read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size) | |
6903 | { | |
6904 | int ret; | |
6905 | ||
6906 | /* Go through a union so this works on either big or little endian | |
6907 | hosts, when the inferior's pointer size is smaller than the size | |
6908 | of CORE_ADDR. It is assumed the inferior's endianness is the | |
6909 | same of the superior's. */ | |
6910 | union | |
6911 | { | |
6912 | CORE_ADDR core_addr; | |
6913 | unsigned int ui; | |
6914 | unsigned char uc; | |
6915 | } addr; | |
6916 | ||
6917 | ret = linux_read_memory (memaddr, &addr.uc, ptr_size); | |
6918 | if (ret == 0) | |
6919 | { | |
6920 | if (ptr_size == sizeof (CORE_ADDR)) | |
6921 | *ptr = addr.core_addr; | |
6922 | else if (ptr_size == sizeof (unsigned int)) | |
6923 | *ptr = addr.ui; | |
6924 | else | |
6925 | gdb_assert_not_reached ("unhandled pointer size"); | |
6926 | } | |
6927 | return ret; | |
6928 | } | |
6929 | ||
6930 | struct link_map_offsets | |
6931 | { | |
6932 | /* Offset and size of r_debug.r_version. */ | |
6933 | int r_version_offset; | |
6934 | ||
6935 | /* Offset and size of r_debug.r_map. */ | |
6936 | int r_map_offset; | |
6937 | ||
6938 | /* Offset to l_addr field in struct link_map. */ | |
6939 | int l_addr_offset; | |
6940 | ||
6941 | /* Offset to l_name field in struct link_map. */ | |
6942 | int l_name_offset; | |
6943 | ||
6944 | /* Offset to l_ld field in struct link_map. */ | |
6945 | int l_ld_offset; | |
6946 | ||
6947 | /* Offset to l_next field in struct link_map. */ | |
6948 | int l_next_offset; | |
6949 | ||
6950 | /* Offset to l_prev field in struct link_map. */ | |
6951 | int l_prev_offset; | |
6952 | }; | |
6953 | ||
6954 | /* Construct qXfer:libraries-svr4:read reply. */ | |
6955 | ||
6956 | static int | |
6957 | linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf, | |
6958 | unsigned const char *writebuf, | |
6959 | CORE_ADDR offset, int len) | |
6960 | { | |
6961 | char *document; | |
6962 | unsigned document_len; | |
6963 | struct process_info_private *const priv = current_process ()->priv; | |
6964 | char filename[PATH_MAX]; | |
6965 | int pid, is_elf64; | |
6966 | ||
6967 | static const struct link_map_offsets lmo_32bit_offsets = | |
6968 | { | |
6969 | 0, /* r_version offset. */ | |
6970 | 4, /* r_debug.r_map offset. */ | |
6971 | 0, /* l_addr offset in link_map. */ | |
6972 | 4, /* l_name offset in link_map. */ | |
6973 | 8, /* l_ld offset in link_map. */ | |
6974 | 12, /* l_next offset in link_map. */ | |
6975 | 16 /* l_prev offset in link_map. */ | |
6976 | }; | |
6977 | ||
6978 | static const struct link_map_offsets lmo_64bit_offsets = | |
6979 | { | |
6980 | 0, /* r_version offset. */ | |
6981 | 8, /* r_debug.r_map offset. */ | |
6982 | 0, /* l_addr offset in link_map. */ | |
6983 | 8, /* l_name offset in link_map. */ | |
6984 | 16, /* l_ld offset in link_map. */ | |
6985 | 24, /* l_next offset in link_map. */ | |
6986 | 32 /* l_prev offset in link_map. */ | |
6987 | }; | |
6988 | const struct link_map_offsets *lmo; | |
6989 | unsigned int machine; | |
6990 | int ptr_size; | |
6991 | CORE_ADDR lm_addr = 0, lm_prev = 0; | |
6992 | int allocated = 1024; | |
6993 | char *p; | |
6994 | CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev; | |
6995 | int header_done = 0; | |
6996 | ||
6997 | if (writebuf != NULL) | |
6998 | return -2; | |
6999 | if (readbuf == NULL) | |
7000 | return -1; | |
7001 | ||
7002 | pid = lwpid_of (current_thread); | |
7003 | xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid); | |
7004 | is_elf64 = elf_64_file_p (filename, &machine); | |
7005 | lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets; | |
7006 | ptr_size = is_elf64 ? 8 : 4; | |
7007 | ||
7008 | while (annex[0] != '\0') | |
7009 | { | |
7010 | const char *sep; | |
7011 | CORE_ADDR *addrp; | |
7012 | int len; | |
7013 | ||
7014 | sep = strchr (annex, '='); | |
7015 | if (sep == NULL) | |
7016 | break; | |
7017 | ||
7018 | len = sep - annex; | |
7019 | if (len == 5 && startswith (annex, "start")) | |
7020 | addrp = &lm_addr; | |
7021 | else if (len == 4 && startswith (annex, "prev")) | |
7022 | addrp = &lm_prev; | |
7023 | else | |
7024 | { | |
7025 | annex = strchr (sep, ';'); | |
7026 | if (annex == NULL) | |
7027 | break; | |
7028 | annex++; | |
7029 | continue; | |
7030 | } | |
7031 | ||
7032 | annex = decode_address_to_semicolon (addrp, sep + 1); | |
7033 | } | |
7034 | ||
7035 | if (lm_addr == 0) | |
7036 | { | |
7037 | int r_version = 0; | |
7038 | ||
7039 | if (priv->r_debug == 0) | |
7040 | priv->r_debug = get_r_debug (pid, is_elf64); | |
7041 | ||
7042 | /* We failed to find DT_DEBUG. Such situation will not change | |
7043 | for this inferior - do not retry it. Report it to GDB as | |
7044 | E01, see for the reasons at the GDB solib-svr4.c side. */ | |
7045 | if (priv->r_debug == (CORE_ADDR) -1) | |
7046 | return -1; | |
7047 | ||
7048 | if (priv->r_debug != 0) | |
7049 | { | |
7050 | if (linux_read_memory (priv->r_debug + lmo->r_version_offset, | |
7051 | (unsigned char *) &r_version, | |
7052 | sizeof (r_version)) != 0 | |
7053 | || r_version != 1) | |
7054 | { | |
7055 | warning ("unexpected r_debug version %d", r_version); | |
7056 | } | |
7057 | else if (read_one_ptr (priv->r_debug + lmo->r_map_offset, | |
7058 | &lm_addr, ptr_size) != 0) | |
7059 | { | |
7060 | warning ("unable to read r_map from 0x%lx", | |
7061 | (long) priv->r_debug + lmo->r_map_offset); | |
7062 | } | |
7063 | } | |
7064 | } | |
7065 | ||
7066 | document = (char *) xmalloc (allocated); | |
7067 | strcpy (document, "<library-list-svr4 version=\"1.0\""); | |
7068 | p = document + strlen (document); | |
7069 | ||
7070 | while (lm_addr | |
7071 | && read_one_ptr (lm_addr + lmo->l_name_offset, | |
7072 | &l_name, ptr_size) == 0 | |
7073 | && read_one_ptr (lm_addr + lmo->l_addr_offset, | |
7074 | &l_addr, ptr_size) == 0 | |
7075 | && read_one_ptr (lm_addr + lmo->l_ld_offset, | |
7076 | &l_ld, ptr_size) == 0 | |
7077 | && read_one_ptr (lm_addr + lmo->l_prev_offset, | |
7078 | &l_prev, ptr_size) == 0 | |
7079 | && read_one_ptr (lm_addr + lmo->l_next_offset, | |
7080 | &l_next, ptr_size) == 0) | |
7081 | { | |
7082 | unsigned char libname[PATH_MAX]; | |
7083 | ||
7084 | if (lm_prev != l_prev) | |
7085 | { | |
7086 | warning ("Corrupted shared library list: 0x%lx != 0x%lx", | |
7087 | (long) lm_prev, (long) l_prev); | |
7088 | break; | |
7089 | } | |
7090 | ||
7091 | /* Ignore the first entry even if it has valid name as the first entry | |
7092 | corresponds to the main executable. The first entry should not be | |
7093 | skipped if the dynamic loader was loaded late by a static executable | |
7094 | (see solib-svr4.c parameter ignore_first). But in such case the main | |
7095 | executable does not have PT_DYNAMIC present and this function already | |
7096 | exited above due to failed get_r_debug. */ | |
7097 | if (lm_prev == 0) | |
7098 | { | |
7099 | sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr); | |
7100 | p = p + strlen (p); | |
7101 | } | |
7102 | else | |
7103 | { | |
7104 | /* Not checking for error because reading may stop before | |
7105 | we've got PATH_MAX worth of characters. */ | |
7106 | libname[0] = '\0'; | |
7107 | linux_read_memory (l_name, libname, sizeof (libname) - 1); | |
7108 | libname[sizeof (libname) - 1] = '\0'; | |
7109 | if (libname[0] != '\0') | |
7110 | { | |
7111 | /* 6x the size for xml_escape_text below. */ | |
7112 | size_t len = 6 * strlen ((char *) libname); | |
7113 | char *name; | |
7114 | ||
7115 | if (!header_done) | |
7116 | { | |
7117 | /* Terminate `<library-list-svr4'. */ | |
7118 | *p++ = '>'; | |
7119 | header_done = 1; | |
7120 | } | |
7121 | ||
7122 | while (allocated < p - document + len + 200) | |
7123 | { | |
7124 | /* Expand to guarantee sufficient storage. */ | |
7125 | uintptr_t document_len = p - document; | |
7126 | ||
7127 | document = (char *) xrealloc (document, 2 * allocated); | |
7128 | allocated *= 2; | |
7129 | p = document + document_len; | |
7130 | } | |
7131 | ||
7132 | name = xml_escape_text ((char *) libname); | |
7133 | p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" " | |
7134 | "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>", | |
7135 | name, (unsigned long) lm_addr, | |
7136 | (unsigned long) l_addr, (unsigned long) l_ld); | |
7137 | free (name); | |
7138 | } | |
7139 | } | |
7140 | ||
7141 | lm_prev = lm_addr; | |
7142 | lm_addr = l_next; | |
7143 | } | |
7144 | ||
7145 | if (!header_done) | |
7146 | { | |
7147 | /* Empty list; terminate `<library-list-svr4'. */ | |
7148 | strcpy (p, "/>"); | |
7149 | } | |
7150 | else | |
7151 | strcpy (p, "</library-list-svr4>"); | |
7152 | ||
7153 | document_len = strlen (document); | |
7154 | if (offset < document_len) | |
7155 | document_len -= offset; | |
7156 | else | |
7157 | document_len = 0; | |
7158 | if (len > document_len) | |
7159 | len = document_len; | |
7160 | ||
7161 | memcpy (readbuf, document + offset, len); | |
7162 | xfree (document); | |
7163 | ||
7164 | return len; | |
7165 | } | |
7166 | ||
7167 | #ifdef HAVE_LINUX_BTRACE | |
7168 | ||
7169 | /* See to_disable_btrace target method. */ | |
7170 | ||
7171 | static int | |
7172 | linux_low_disable_btrace (struct btrace_target_info *tinfo) | |
7173 | { | |
7174 | enum btrace_error err; | |
7175 | ||
7176 | err = linux_disable_btrace (tinfo); | |
7177 | return (err == BTRACE_ERR_NONE ? 0 : -1); | |
7178 | } | |
7179 | ||
7180 | /* Encode an Intel Processor Trace configuration. */ | |
7181 | ||
7182 | static void | |
7183 | linux_low_encode_pt_config (struct buffer *buffer, | |
7184 | const struct btrace_data_pt_config *config) | |
7185 | { | |
7186 | buffer_grow_str (buffer, "<pt-config>\n"); | |
7187 | ||
7188 | switch (config->cpu.vendor) | |
7189 | { | |
7190 | case CV_INTEL: | |
7191 | buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" " | |
7192 | "model=\"%u\" stepping=\"%u\"/>\n", | |
7193 | config->cpu.family, config->cpu.model, | |
7194 | config->cpu.stepping); | |
7195 | break; | |
7196 | ||
7197 | default: | |
7198 | break; | |
7199 | } | |
7200 | ||
7201 | buffer_grow_str (buffer, "</pt-config>\n"); | |
7202 | } | |
7203 | ||
7204 | /* Encode a raw buffer. */ | |
7205 | ||
7206 | static void | |
7207 | linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data, | |
7208 | unsigned int size) | |
7209 | { | |
7210 | if (size == 0) | |
7211 | return; | |
7212 | ||
7213 | /* We use hex encoding - see common/rsp-low.h. */ | |
7214 | buffer_grow_str (buffer, "<raw>\n"); | |
7215 | ||
7216 | while (size-- > 0) | |
7217 | { | |
7218 | char elem[2]; | |
7219 | ||
7220 | elem[0] = tohex ((*data >> 4) & 0xf); | |
7221 | elem[1] = tohex (*data++ & 0xf); | |
7222 | ||
7223 | buffer_grow (buffer, elem, 2); | |
7224 | } | |
7225 | ||
7226 | buffer_grow_str (buffer, "</raw>\n"); | |
7227 | } | |
7228 | ||
7229 | /* See to_read_btrace target method. */ | |
7230 | ||
7231 | static int | |
7232 | linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer, | |
7233 | enum btrace_read_type type) | |
7234 | { | |
7235 | struct btrace_data btrace; | |
7236 | struct btrace_block *block; | |
7237 | enum btrace_error err; | |
7238 | int i; | |
7239 | ||
7240 | btrace_data_init (&btrace); | |
7241 | ||
7242 | err = linux_read_btrace (&btrace, tinfo, type); | |
7243 | if (err != BTRACE_ERR_NONE) | |
7244 | { | |
7245 | if (err == BTRACE_ERR_OVERFLOW) | |
7246 | buffer_grow_str0 (buffer, "E.Overflow."); | |
7247 | else | |
7248 | buffer_grow_str0 (buffer, "E.Generic Error."); | |
7249 | ||
7250 | goto err; | |
7251 | } | |
7252 | ||
7253 | switch (btrace.format) | |
7254 | { | |
7255 | case BTRACE_FORMAT_NONE: | |
7256 | buffer_grow_str0 (buffer, "E.No Trace."); | |
7257 | goto err; | |
7258 | ||
7259 | case BTRACE_FORMAT_BTS: | |
7260 | buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n"); | |
7261 | buffer_grow_str (buffer, "<btrace version=\"1.0\">\n"); | |
7262 | ||
7263 | for (i = 0; | |
7264 | VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block); | |
7265 | i++) | |
7266 | buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n", | |
7267 | paddress (block->begin), paddress (block->end)); | |
7268 | ||
7269 | buffer_grow_str0 (buffer, "</btrace>\n"); | |
7270 | break; | |
7271 | ||
7272 | case BTRACE_FORMAT_PT: | |
7273 | buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n"); | |
7274 | buffer_grow_str (buffer, "<btrace version=\"1.0\">\n"); | |
7275 | buffer_grow_str (buffer, "<pt>\n"); | |
7276 | ||
7277 | linux_low_encode_pt_config (buffer, &btrace.variant.pt.config); | |
7278 | ||
7279 | linux_low_encode_raw (buffer, btrace.variant.pt.data, | |
7280 | btrace.variant.pt.size); | |
7281 | ||
7282 | buffer_grow_str (buffer, "</pt>\n"); | |
7283 | buffer_grow_str0 (buffer, "</btrace>\n"); | |
7284 | break; | |
7285 | ||
7286 | default: | |
7287 | buffer_grow_str0 (buffer, "E.Unsupported Trace Format."); | |
7288 | goto err; | |
7289 | } | |
7290 | ||
7291 | btrace_data_fini (&btrace); | |
7292 | return 0; | |
7293 | ||
7294 | err: | |
7295 | btrace_data_fini (&btrace); | |
7296 | return -1; | |
7297 | } | |
7298 | ||
7299 | /* See to_btrace_conf target method. */ | |
7300 | ||
7301 | static int | |
7302 | linux_low_btrace_conf (const struct btrace_target_info *tinfo, | |
7303 | struct buffer *buffer) | |
7304 | { | |
7305 | const struct btrace_config *conf; | |
7306 | ||
7307 | buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n"); | |
7308 | buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n"); | |
7309 | ||
7310 | conf = linux_btrace_conf (tinfo); | |
7311 | if (conf != NULL) | |
7312 | { | |
7313 | switch (conf->format) | |
7314 | { | |
7315 | case BTRACE_FORMAT_NONE: | |
7316 | break; | |
7317 | ||
7318 | case BTRACE_FORMAT_BTS: | |
7319 | buffer_xml_printf (buffer, "<bts"); | |
7320 | buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size); | |
7321 | buffer_xml_printf (buffer, " />\n"); | |
7322 | break; | |
7323 | ||
7324 | case BTRACE_FORMAT_PT: | |
7325 | buffer_xml_printf (buffer, "<pt"); | |
7326 | buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size); | |
7327 | buffer_xml_printf (buffer, "/>\n"); | |
7328 | break; | |
7329 | } | |
7330 | } | |
7331 | ||
7332 | buffer_grow_str0 (buffer, "</btrace-conf>\n"); | |
7333 | return 0; | |
7334 | } | |
7335 | #endif /* HAVE_LINUX_BTRACE */ | |
7336 | ||
7337 | /* See nat/linux-nat.h. */ | |
7338 | ||
7339 | ptid_t | |
7340 | current_lwp_ptid (void) | |
7341 | { | |
7342 | return ptid_of (current_thread); | |
7343 | } | |
7344 | ||
7345 | /* Implementation of the target_ops method "breakpoint_kind_from_pc". */ | |
7346 | ||
7347 | static int | |
7348 | linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr) | |
7349 | { | |
7350 | if (the_low_target.breakpoint_kind_from_pc != NULL) | |
7351 | return (*the_low_target.breakpoint_kind_from_pc) (pcptr); | |
7352 | else | |
7353 | return default_breakpoint_kind_from_pc (pcptr); | |
7354 | } | |
7355 | ||
7356 | /* Implementation of the target_ops method "sw_breakpoint_from_kind". */ | |
7357 | ||
7358 | static const gdb_byte * | |
7359 | linux_sw_breakpoint_from_kind (int kind, int *size) | |
7360 | { | |
7361 | gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL); | |
7362 | ||
7363 | return (*the_low_target.sw_breakpoint_from_kind) (kind, size); | |
7364 | } | |
7365 | ||
7366 | /* Implementation of the target_ops method | |
7367 | "breakpoint_kind_from_current_state". */ | |
7368 | ||
7369 | static int | |
7370 | linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr) | |
7371 | { | |
7372 | if (the_low_target.breakpoint_kind_from_current_state != NULL) | |
7373 | return (*the_low_target.breakpoint_kind_from_current_state) (pcptr); | |
7374 | else | |
7375 | return linux_breakpoint_kind_from_pc (pcptr); | |
7376 | } | |
7377 | ||
7378 | /* Default implementation of linux_target_ops method "set_pc" for | |
7379 | 32-bit pc register which is literally named "pc". */ | |
7380 | ||
7381 | void | |
7382 | linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc) | |
7383 | { | |
7384 | uint32_t newpc = pc; | |
7385 | ||
7386 | supply_register_by_name (regcache, "pc", &newpc); | |
7387 | } | |
7388 | ||
7389 | /* Default implementation of linux_target_ops method "get_pc" for | |
7390 | 32-bit pc register which is literally named "pc". */ | |
7391 | ||
7392 | CORE_ADDR | |
7393 | linux_get_pc_32bit (struct regcache *regcache) | |
7394 | { | |
7395 | uint32_t pc; | |
7396 | ||
7397 | collect_register_by_name (regcache, "pc", &pc); | |
7398 | if (debug_threads) | |
7399 | debug_printf ("stop pc is 0x%" PRIx32 "\n", pc); | |
7400 | return pc; | |
7401 | } | |
7402 | ||
7403 | /* Default implementation of linux_target_ops method "set_pc" for | |
7404 | 64-bit pc register which is literally named "pc". */ | |
7405 | ||
7406 | void | |
7407 | linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc) | |
7408 | { | |
7409 | uint64_t newpc = pc; | |
7410 | ||
7411 | supply_register_by_name (regcache, "pc", &newpc); | |
7412 | } | |
7413 | ||
7414 | /* Default implementation of linux_target_ops method "get_pc" for | |
7415 | 64-bit pc register which is literally named "pc". */ | |
7416 | ||
7417 | CORE_ADDR | |
7418 | linux_get_pc_64bit (struct regcache *regcache) | |
7419 | { | |
7420 | uint64_t pc; | |
7421 | ||
7422 | collect_register_by_name (regcache, "pc", &pc); | |
7423 | if (debug_threads) | |
7424 | debug_printf ("stop pc is 0x%" PRIx64 "\n", pc); | |
7425 | return pc; | |
7426 | } | |
7427 | ||
7428 | ||
7429 | static struct target_ops linux_target_ops = { | |
7430 | linux_create_inferior, | |
7431 | linux_post_create_inferior, | |
7432 | linux_attach, | |
7433 | linux_kill, | |
7434 | linux_detach, | |
7435 | linux_mourn, | |
7436 | linux_join, | |
7437 | linux_thread_alive, | |
7438 | linux_resume, | |
7439 | linux_wait, | |
7440 | linux_fetch_registers, | |
7441 | linux_store_registers, | |
7442 | linux_prepare_to_access_memory, | |
7443 | linux_done_accessing_memory, | |
7444 | linux_read_memory, | |
7445 | linux_write_memory, | |
7446 | linux_look_up_symbols, | |
7447 | linux_request_interrupt, | |
7448 | linux_read_auxv, | |
7449 | linux_supports_z_point_type, | |
7450 | linux_insert_point, | |
7451 | linux_remove_point, | |
7452 | linux_stopped_by_sw_breakpoint, | |
7453 | linux_supports_stopped_by_sw_breakpoint, | |
7454 | linux_stopped_by_hw_breakpoint, | |
7455 | linux_supports_stopped_by_hw_breakpoint, | |
7456 | linux_supports_hardware_single_step, | |
7457 | linux_stopped_by_watchpoint, | |
7458 | linux_stopped_data_address, | |
7459 | #if defined(__UCLIBC__) && defined(HAS_NOMMU) \ | |
7460 | && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \ | |
7461 | && defined(PT_TEXT_END_ADDR) | |
7462 | linux_read_offsets, | |
7463 | #else | |
7464 | NULL, | |
7465 | #endif | |
7466 | #ifdef USE_THREAD_DB | |
7467 | thread_db_get_tls_address, | |
7468 | #else | |
7469 | NULL, | |
7470 | #endif | |
7471 | linux_qxfer_spu, | |
7472 | hostio_last_error_from_errno, | |
7473 | linux_qxfer_osdata, | |
7474 | linux_xfer_siginfo, | |
7475 | linux_supports_non_stop, | |
7476 | linux_async, | |
7477 | linux_start_non_stop, | |
7478 | linux_supports_multi_process, | |
7479 | linux_supports_fork_events, | |
7480 | linux_supports_vfork_events, | |
7481 | linux_supports_exec_events, | |
7482 | linux_handle_new_gdb_connection, | |
7483 | #ifdef USE_THREAD_DB | |
7484 | thread_db_handle_monitor_command, | |
7485 | #else | |
7486 | NULL, | |
7487 | #endif | |
7488 | linux_common_core_of_thread, | |
7489 | linux_read_loadmap, | |
7490 | linux_process_qsupported, | |
7491 | linux_supports_tracepoints, | |
7492 | linux_read_pc, | |
7493 | linux_write_pc, | |
7494 | linux_thread_stopped, | |
7495 | NULL, | |
7496 | linux_pause_all, | |
7497 | linux_unpause_all, | |
7498 | linux_stabilize_threads, | |
7499 | linux_install_fast_tracepoint_jump_pad, | |
7500 | linux_emit_ops, | |
7501 | linux_supports_disable_randomization, | |
7502 | linux_get_min_fast_tracepoint_insn_len, | |
7503 | linux_qxfer_libraries_svr4, | |
7504 | linux_supports_agent, | |
7505 | #ifdef HAVE_LINUX_BTRACE | |
7506 | linux_supports_btrace, | |
7507 | linux_enable_btrace, | |
7508 | linux_low_disable_btrace, | |
7509 | linux_low_read_btrace, | |
7510 | linux_low_btrace_conf, | |
7511 | #else | |
7512 | NULL, | |
7513 | NULL, | |
7514 | NULL, | |
7515 | NULL, | |
7516 | NULL, | |
7517 | #endif | |
7518 | linux_supports_range_stepping, | |
7519 | linux_proc_pid_to_exec_file, | |
7520 | linux_mntns_open_cloexec, | |
7521 | linux_mntns_unlink, | |
7522 | linux_mntns_readlink, | |
7523 | linux_breakpoint_kind_from_pc, | |
7524 | linux_sw_breakpoint_from_kind, | |
7525 | linux_proc_tid_get_name, | |
7526 | linux_breakpoint_kind_from_current_state, | |
7527 | linux_supports_software_single_step, | |
7528 | linux_supports_catch_syscall, | |
7529 | linux_get_ipa_tdesc_idx, | |
7530 | }; | |
7531 | ||
7532 | #ifdef HAVE_LINUX_REGSETS | |
7533 | void | |
7534 | initialize_regsets_info (struct regsets_info *info) | |
7535 | { | |
7536 | for (info->num_regsets = 0; | |
7537 | info->regsets[info->num_regsets].size >= 0; | |
7538 | info->num_regsets++) | |
7539 | ; | |
7540 | } | |
7541 | #endif | |
7542 | ||
7543 | void | |
7544 | initialize_low (void) | |
7545 | { | |
7546 | struct sigaction sigchld_action; | |
7547 | ||
7548 | memset (&sigchld_action, 0, sizeof (sigchld_action)); | |
7549 | set_target_ops (&linux_target_ops); | |
7550 | ||
7551 | linux_ptrace_init_warnings (); | |
7552 | ||
7553 | sigchld_action.sa_handler = sigchld_handler; | |
7554 | sigemptyset (&sigchld_action.sa_mask); | |
7555 | sigchld_action.sa_flags = SA_RESTART; | |
7556 | sigaction (SIGCHLD, &sigchld_action, NULL); | |
7557 | ||
7558 | initialize_low_arch (); | |
7559 | ||
7560 | linux_check_ptrace_features (); | |
7561 | } |