2003-04-15 H.J. Lu <hjl@gnu.org>
[deliverable/binutils-gdb.git] / gdb / thread.c
1 /* Multi-process/thread control for GDB, the GNU debugger.
2
3 Copyright 1986, 1987, 1988, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
5
6 Contributed by Lynx Real-Time Systems, Inc. Los Gatos, CA.
7
8 This file is part of GDB.
9
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
14
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
19
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
24
25 #include "defs.h"
26 #include "symtab.h"
27 #include "frame.h"
28 #include "inferior.h"
29 #include "environ.h"
30 #include "value.h"
31 #include "target.h"
32 #include "gdbthread.h"
33 #include "command.h"
34 #include "gdbcmd.h"
35 #include "regcache.h"
36 #include "gdb.h"
37 #include "gdb_string.h"
38
39 #include <ctype.h>
40 #include <sys/types.h>
41 #include <signal.h>
42 #include "ui-out.h"
43
44 /*#include "lynxos-core.h" */
45
46 /* Definition of struct thread_info exported to gdbthread.h */
47
48 /* Prototypes for exported functions. */
49
50 void _initialize_thread (void);
51
52 /* Prototypes for local functions. */
53
54 static struct thread_info *thread_list = NULL;
55 static int highest_thread_num;
56
57 static struct thread_info *find_thread_id (int num);
58
59 static void thread_command (char *tidstr, int from_tty);
60 static void thread_apply_all_command (char *, int);
61 static int thread_alive (struct thread_info *);
62 static void info_threads_command (char *, int);
63 static void thread_apply_command (char *, int);
64 static void restore_current_thread (ptid_t);
65 static void switch_to_thread (ptid_t ptid);
66 static void prune_threads (void);
67
68 void
69 delete_step_resume_breakpoint (void *arg)
70 {
71 struct breakpoint **breakpointp = (struct breakpoint **) arg;
72 struct thread_info *tp;
73
74 if (*breakpointp != NULL)
75 {
76 delete_breakpoint (*breakpointp);
77 for (tp = thread_list; tp; tp = tp->next)
78 if (tp->step_resume_breakpoint == *breakpointp)
79 tp->step_resume_breakpoint = NULL;
80
81 *breakpointp = NULL;
82 }
83 }
84
85 static void
86 free_thread (struct thread_info *tp)
87 {
88 /* NOTE: this will take care of any left-over step_resume breakpoints,
89 but not any user-specified thread-specific breakpoints. */
90 if (tp->step_resume_breakpoint)
91 delete_breakpoint (tp->step_resume_breakpoint);
92
93 /* FIXME: do I ever need to call the back-end to give it a
94 chance at this private data before deleting the thread? */
95 if (tp->private)
96 xfree (tp->private);
97
98 xfree (tp);
99 }
100
101 void
102 init_thread_list (void)
103 {
104 struct thread_info *tp, *tpnext;
105
106 highest_thread_num = 0;
107 if (!thread_list)
108 return;
109
110 for (tp = thread_list; tp; tp = tpnext)
111 {
112 tpnext = tp->next;
113 free_thread (tp);
114 }
115
116 thread_list = NULL;
117 }
118
119 /* add_thread now returns a pointer to the new thread_info,
120 so that back_ends can initialize their private data. */
121
122 struct thread_info *
123 add_thread (ptid_t ptid)
124 {
125 struct thread_info *tp;
126
127 tp = (struct thread_info *) xmalloc (sizeof (*tp));
128 memset (tp, 0, sizeof (*tp));
129 tp->ptid = ptid;
130 tp->num = ++highest_thread_num;
131 tp->next = thread_list;
132 thread_list = tp;
133 return tp;
134 }
135
136 void
137 delete_thread (ptid_t ptid)
138 {
139 struct thread_info *tp, *tpprev;
140
141 tpprev = NULL;
142
143 for (tp = thread_list; tp; tpprev = tp, tp = tp->next)
144 if (ptid_equal (tp->ptid, ptid))
145 break;
146
147 if (!tp)
148 return;
149
150 if (tpprev)
151 tpprev->next = tp->next;
152 else
153 thread_list = tp->next;
154
155 free_thread (tp);
156 }
157
158 static struct thread_info *
159 find_thread_id (int num)
160 {
161 struct thread_info *tp;
162
163 for (tp = thread_list; tp; tp = tp->next)
164 if (tp->num == num)
165 return tp;
166
167 return NULL;
168 }
169
170 /* Find a thread_info by matching PTID. */
171 struct thread_info *
172 find_thread_pid (ptid_t ptid)
173 {
174 struct thread_info *tp;
175
176 for (tp = thread_list; tp; tp = tp->next)
177 if (ptid_equal (tp->ptid, ptid))
178 return tp;
179
180 return NULL;
181 }
182
183 /*
184 * Thread iterator function.
185 *
186 * Calls a callback function once for each thread, so long as
187 * the callback function returns false. If the callback function
188 * returns true, the iteration will end and the current thread
189 * will be returned. This can be useful for implementing a
190 * search for a thread with arbitrary attributes, or for applying
191 * some operation to every thread.
192 *
193 * FIXME: some of the existing functionality, such as
194 * "Thread apply all", might be rewritten using this functionality.
195 */
196
197 struct thread_info *
198 iterate_over_threads (int (*callback) (struct thread_info *, void *),
199 void *data)
200 {
201 struct thread_info *tp;
202
203 for (tp = thread_list; tp; tp = tp->next)
204 if ((*callback) (tp, data))
205 return tp;
206
207 return NULL;
208 }
209
210 int
211 valid_thread_id (int num)
212 {
213 struct thread_info *tp;
214
215 for (tp = thread_list; tp; tp = tp->next)
216 if (tp->num == num)
217 return 1;
218
219 return 0;
220 }
221
222 int
223 pid_to_thread_id (ptid_t ptid)
224 {
225 struct thread_info *tp;
226
227 for (tp = thread_list; tp; tp = tp->next)
228 if (ptid_equal (tp->ptid, ptid))
229 return tp->num;
230
231 return 0;
232 }
233
234 ptid_t
235 thread_id_to_pid (int num)
236 {
237 struct thread_info *thread = find_thread_id (num);
238 if (thread)
239 return thread->ptid;
240 else
241 return pid_to_ptid (-1);
242 }
243
244 int
245 in_thread_list (ptid_t ptid)
246 {
247 struct thread_info *tp;
248
249 for (tp = thread_list; tp; tp = tp->next)
250 if (ptid_equal (tp->ptid, ptid))
251 return 1;
252
253 return 0; /* Never heard of 'im */
254 }
255
256 /* Print a list of thread ids currently known, and the total number of
257 threads. To be used from within catch_errors. */
258 static int
259 do_captured_list_thread_ids (struct ui_out *uiout, void *arg)
260 {
261 struct thread_info *tp;
262 int num = 0;
263 struct cleanup *cleanup_chain;
264
265 prune_threads ();
266 target_find_new_threads ();
267
268 cleanup_chain = make_cleanup_ui_out_tuple_begin_end (uiout, "thread-ids");
269
270 for (tp = thread_list; tp; tp = tp->next)
271 {
272 num++;
273 ui_out_field_int (uiout, "thread-id", tp->num);
274 }
275
276 do_cleanups (cleanup_chain);
277 ui_out_field_int (uiout, "number-of-threads", num);
278 return GDB_RC_OK;
279 }
280
281 /* Official gdblib interface function to get a list of thread ids and
282 the total number. */
283 enum gdb_rc
284 gdb_list_thread_ids (struct ui_out *uiout)
285 {
286 return catch_exceptions (uiout, do_captured_list_thread_ids, NULL,
287 NULL, RETURN_MASK_ALL);
288 }
289
290 /* Load infrun state for the thread PID. */
291
292 void
293 load_infrun_state (ptid_t ptid,
294 CORE_ADDR *prev_pc,
295 char **prev_func_name,
296 int *trap_expected,
297 struct breakpoint **step_resume_breakpoint,
298 struct breakpoint **through_sigtramp_breakpoint,
299 CORE_ADDR *step_range_start,
300 CORE_ADDR *step_range_end,
301 struct frame_id *step_frame_id,
302 int *handling_longjmp,
303 int *another_trap,
304 int *stepping_through_solib_after_catch,
305 bpstat *stepping_through_solib_catchpoints,
306 int *stepping_through_sigtramp,
307 int *current_line,
308 struct symtab **current_symtab, CORE_ADDR *step_sp)
309 {
310 struct thread_info *tp;
311
312 /* If we can't find the thread, then we're debugging a single threaded
313 process. No need to do anything in that case. */
314 tp = find_thread_id (pid_to_thread_id (ptid));
315 if (tp == NULL)
316 return;
317
318 *prev_pc = tp->prev_pc;
319 *prev_func_name = tp->prev_func_name;
320 *trap_expected = tp->trap_expected;
321 *step_resume_breakpoint = tp->step_resume_breakpoint;
322 *through_sigtramp_breakpoint = tp->through_sigtramp_breakpoint;
323 *step_range_start = tp->step_range_start;
324 *step_range_end = tp->step_range_end;
325 *step_frame_id = tp->step_frame_id;
326 *handling_longjmp = tp->handling_longjmp;
327 *another_trap = tp->another_trap;
328 *stepping_through_solib_after_catch =
329 tp->stepping_through_solib_after_catch;
330 *stepping_through_solib_catchpoints =
331 tp->stepping_through_solib_catchpoints;
332 *stepping_through_sigtramp = tp->stepping_through_sigtramp;
333 *current_line = tp->current_line;
334 *current_symtab = tp->current_symtab;
335 *step_sp = tp->step_sp;
336 }
337
338 /* Save infrun state for the thread PID. */
339
340 void
341 save_infrun_state (ptid_t ptid,
342 CORE_ADDR prev_pc,
343 char *prev_func_name,
344 int trap_expected,
345 struct breakpoint *step_resume_breakpoint,
346 struct breakpoint *through_sigtramp_breakpoint,
347 CORE_ADDR step_range_start,
348 CORE_ADDR step_range_end,
349 const struct frame_id *step_frame_id,
350 int handling_longjmp,
351 int another_trap,
352 int stepping_through_solib_after_catch,
353 bpstat stepping_through_solib_catchpoints,
354 int stepping_through_sigtramp,
355 int current_line,
356 struct symtab *current_symtab, CORE_ADDR step_sp)
357 {
358 struct thread_info *tp;
359
360 /* If we can't find the thread, then we're debugging a single-threaded
361 process. Nothing to do in that case. */
362 tp = find_thread_id (pid_to_thread_id (ptid));
363 if (tp == NULL)
364 return;
365
366 tp->prev_pc = prev_pc;
367 tp->prev_func_name = prev_func_name;
368 tp->trap_expected = trap_expected;
369 tp->step_resume_breakpoint = step_resume_breakpoint;
370 tp->through_sigtramp_breakpoint = through_sigtramp_breakpoint;
371 tp->step_range_start = step_range_start;
372 tp->step_range_end = step_range_end;
373 tp->step_frame_id = (*step_frame_id);
374 tp->handling_longjmp = handling_longjmp;
375 tp->another_trap = another_trap;
376 tp->stepping_through_solib_after_catch = stepping_through_solib_after_catch;
377 tp->stepping_through_solib_catchpoints = stepping_through_solib_catchpoints;
378 tp->stepping_through_sigtramp = stepping_through_sigtramp;
379 tp->current_line = current_line;
380 tp->current_symtab = current_symtab;
381 tp->step_sp = step_sp;
382 }
383
384 /* Return true if TP is an active thread. */
385 static int
386 thread_alive (struct thread_info *tp)
387 {
388 if (PIDGET (tp->ptid) == -1)
389 return 0;
390 if (!target_thread_alive (tp->ptid))
391 {
392 tp->ptid = pid_to_ptid (-1); /* Mark it as dead */
393 return 0;
394 }
395 return 1;
396 }
397
398 static void
399 prune_threads (void)
400 {
401 struct thread_info *tp, *next;
402
403 for (tp = thread_list; tp; tp = next)
404 {
405 next = tp->next;
406 if (!thread_alive (tp))
407 delete_thread (tp->ptid);
408 }
409 }
410
411 /* Print information about currently known threads
412
413 * Note: this has the drawback that it _really_ switches
414 * threads, which frees the frame cache. A no-side
415 * effects info-threads command would be nicer.
416 */
417
418 static void
419 info_threads_command (char *arg, int from_tty)
420 {
421 struct thread_info *tp;
422 ptid_t current_ptid;
423 struct frame_info *cur_frame;
424 int saved_frame_level = frame_relative_level (deprecated_selected_frame);
425 int counter;
426 char *extra_info;
427
428 /* Avoid coredumps which would happen if we tried to access a NULL
429 deprecated_selected_frame. */
430 if (!target_has_stack)
431 error ("No stack.");
432
433 prune_threads ();
434 target_find_new_threads ();
435 current_ptid = inferior_ptid;
436 for (tp = thread_list; tp; tp = tp->next)
437 {
438 if (ptid_equal (tp->ptid, current_ptid))
439 printf_filtered ("* ");
440 else
441 printf_filtered (" ");
442
443 #ifdef HPUXHPPA
444 printf_filtered ("%d %s", tp->num, target_tid_to_str (tp->ptid));
445 #else
446 printf_filtered ("%d %s", tp->num, target_pid_to_str (tp->ptid));
447 #endif
448
449 extra_info = target_extra_thread_info (tp);
450 if (extra_info)
451 printf_filtered (" (%s)", extra_info);
452 puts_filtered (" ");
453
454 switch_to_thread (tp->ptid);
455 if (deprecated_selected_frame)
456 print_stack_frame (deprecated_selected_frame, -1, 0);
457 else
458 printf_filtered ("[No stack.]\n");
459 }
460
461 switch_to_thread (current_ptid);
462
463 /* Code below copied from "up_silently_base" in "stack.c".
464 * It restores the frame set by the user before the "info threads"
465 * command. We have finished the info-threads display by switching
466 * back to the current thread. That switch has put us at the top
467 * of the stack (leaf frame).
468 */
469 counter = saved_frame_level;
470 cur_frame = find_relative_frame (deprecated_selected_frame, &counter);
471 if (counter != 0)
472 {
473 /* Ooops, can't restore, tell user where we are. */
474 warning ("Couldn't restore frame in current thread, at frame 0");
475 print_stack_frame (deprecated_selected_frame, -1, 0);
476 }
477 else
478 {
479 select_frame (cur_frame);
480 }
481
482 /* re-show current frame. */
483 show_stack_frame (cur_frame);
484 }
485
486 /* Switch from one thread to another. */
487
488 static void
489 switch_to_thread (ptid_t ptid)
490 {
491 if (ptid_equal (ptid, inferior_ptid))
492 return;
493
494 inferior_ptid = ptid;
495 flush_cached_frames ();
496 registers_changed ();
497 stop_pc = read_pc ();
498 select_frame (get_current_frame ());
499 }
500
501 static void
502 restore_current_thread (ptid_t ptid)
503 {
504 if (!ptid_equal (ptid, inferior_ptid))
505 {
506 switch_to_thread (ptid);
507 print_stack_frame (get_current_frame (), 0, -1);
508 }
509 }
510
511 struct current_thread_cleanup
512 {
513 ptid_t inferior_ptid;
514 };
515
516 static void
517 do_restore_current_thread_cleanup (void *arg)
518 {
519 struct current_thread_cleanup *old = arg;
520 restore_current_thread (old->inferior_ptid);
521 xfree (old);
522 }
523
524 static struct cleanup *
525 make_cleanup_restore_current_thread (ptid_t inferior_ptid)
526 {
527 struct current_thread_cleanup *old
528 = xmalloc (sizeof (struct current_thread_cleanup));
529 old->inferior_ptid = inferior_ptid;
530 return make_cleanup (do_restore_current_thread_cleanup, old);
531 }
532
533 /* Apply a GDB command to a list of threads. List syntax is a whitespace
534 seperated list of numbers, or ranges, or the keyword `all'. Ranges consist
535 of two numbers seperated by a hyphen. Examples:
536
537 thread apply 1 2 7 4 backtrace Apply backtrace cmd to threads 1,2,7,4
538 thread apply 2-7 9 p foo(1) Apply p foo(1) cmd to threads 2->7 & 9
539 thread apply all p x/i $pc Apply x/i $pc cmd to all threads
540 */
541
542 static void
543 thread_apply_all_command (char *cmd, int from_tty)
544 {
545 struct thread_info *tp;
546 struct cleanup *old_chain;
547 struct cleanup *saved_cmd_cleanup_chain;
548 char *saved_cmd;
549
550 if (cmd == NULL || *cmd == '\000')
551 error ("Please specify a command following the thread ID list");
552
553 old_chain = make_cleanup_restore_current_thread (inferior_ptid);
554
555 /* It is safe to update the thread list now, before
556 traversing it for "thread apply all". MVS */
557 target_find_new_threads ();
558
559 /* Save a copy of the command in case it is clobbered by
560 execute_command */
561 saved_cmd = xstrdup (cmd);
562 saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
563 for (tp = thread_list; tp; tp = tp->next)
564 if (thread_alive (tp))
565 {
566 switch_to_thread (tp->ptid);
567 #ifdef HPUXHPPA
568 printf_filtered ("\nThread %d (%s):\n",
569 tp->num, target_tid_to_str (inferior_ptid));
570 #else
571 printf_filtered ("\nThread %d (%s):\n", tp->num,
572 target_pid_to_str (inferior_ptid));
573 #endif
574 execute_command (cmd, from_tty);
575 strcpy (cmd, saved_cmd); /* Restore exact command used previously */
576 }
577
578 do_cleanups (saved_cmd_cleanup_chain);
579 do_cleanups (old_chain);
580 }
581
582 static void
583 thread_apply_command (char *tidlist, int from_tty)
584 {
585 char *cmd;
586 char *p;
587 struct cleanup *old_chain;
588 struct cleanup *saved_cmd_cleanup_chain;
589 char *saved_cmd;
590
591 if (tidlist == NULL || *tidlist == '\000')
592 error ("Please specify a thread ID list");
593
594 for (cmd = tidlist; *cmd != '\000' && !isalpha (*cmd); cmd++);
595
596 if (*cmd == '\000')
597 error ("Please specify a command following the thread ID list");
598
599 old_chain = make_cleanup_restore_current_thread (inferior_ptid);
600
601 /* Save a copy of the command in case it is clobbered by
602 execute_command */
603 saved_cmd = xstrdup (cmd);
604 saved_cmd_cleanup_chain = make_cleanup (xfree, (void *) saved_cmd);
605 while (tidlist < cmd)
606 {
607 struct thread_info *tp;
608 int start, end;
609
610 start = strtol (tidlist, &p, 10);
611 if (p == tidlist)
612 error ("Error parsing %s", tidlist);
613 tidlist = p;
614
615 while (*tidlist == ' ' || *tidlist == '\t')
616 tidlist++;
617
618 if (*tidlist == '-') /* Got a range of IDs? */
619 {
620 tidlist++; /* Skip the - */
621 end = strtol (tidlist, &p, 10);
622 if (p == tidlist)
623 error ("Error parsing %s", tidlist);
624 tidlist = p;
625
626 while (*tidlist == ' ' || *tidlist == '\t')
627 tidlist++;
628 }
629 else
630 end = start;
631
632 for (; start <= end; start++)
633 {
634 tp = find_thread_id (start);
635
636 if (!tp)
637 warning ("Unknown thread %d.", start);
638 else if (!thread_alive (tp))
639 warning ("Thread %d has terminated.", start);
640 else
641 {
642 switch_to_thread (tp->ptid);
643 #ifdef HPUXHPPA
644 printf_filtered ("\nThread %d (%s):\n", tp->num,
645 target_tid_to_str (inferior_ptid));
646 #else
647 printf_filtered ("\nThread %d (%s):\n", tp->num,
648 target_pid_to_str (inferior_ptid));
649 #endif
650 execute_command (cmd, from_tty);
651 strcpy (cmd, saved_cmd); /* Restore exact command used previously */
652 }
653 }
654 }
655
656 do_cleanups (saved_cmd_cleanup_chain);
657 do_cleanups (old_chain);
658 }
659
660 /* Switch to the specified thread. Will dispatch off to thread_apply_command
661 if prefix of arg is `apply'. */
662
663 static void
664 thread_command (char *tidstr, int from_tty)
665 {
666 if (!tidstr)
667 {
668 /* Don't generate an error, just say which thread is current. */
669 if (target_has_stack)
670 printf_filtered ("[Current thread is %d (%s)]\n",
671 pid_to_thread_id (inferior_ptid),
672 #if defined(HPUXHPPA)
673 target_tid_to_str (inferior_ptid)
674 #else
675 target_pid_to_str (inferior_ptid)
676 #endif
677 );
678 else
679 error ("No stack.");
680 return;
681 }
682
683 gdb_thread_select (uiout, tidstr);
684 }
685
686 static int
687 do_captured_thread_select (struct ui_out *uiout, void *tidstr)
688 {
689 int num;
690 struct thread_info *tp;
691
692 num = value_as_long (parse_and_eval (tidstr));
693
694 tp = find_thread_id (num);
695
696 if (!tp)
697 error ("Thread ID %d not known.", num);
698
699 if (!thread_alive (tp))
700 error ("Thread ID %d has terminated.\n", num);
701
702 switch_to_thread (tp->ptid);
703
704 ui_out_text (uiout, "[Switching to thread ");
705 ui_out_field_int (uiout, "new-thread-id", pid_to_thread_id (inferior_ptid));
706 ui_out_text (uiout, " (");
707 #if defined(HPUXHPPA)
708 ui_out_text (uiout, target_tid_to_str (inferior_ptid));
709 #else
710 ui_out_text (uiout, target_pid_to_str (inferior_ptid));
711 #endif
712 ui_out_text (uiout, ")]");
713
714 print_stack_frame (deprecated_selected_frame,
715 frame_relative_level (deprecated_selected_frame), 1);
716 return GDB_RC_OK;
717 }
718
719 enum gdb_rc
720 gdb_thread_select (struct ui_out *uiout, char *tidstr)
721 {
722 return catch_exceptions (uiout, do_captured_thread_select, tidstr,
723 NULL, RETURN_MASK_ALL);
724 }
725
726 /* Commands with a prefix of `thread'. */
727 struct cmd_list_element *thread_cmd_list = NULL;
728
729 void
730 _initialize_thread (void)
731 {
732 static struct cmd_list_element *thread_apply_list = NULL;
733
734 add_info ("threads", info_threads_command,
735 "IDs of currently known threads.");
736
737 add_prefix_cmd ("thread", class_run, thread_command,
738 "Use this command to switch between threads.\n\
739 The new thread ID must be currently known.", &thread_cmd_list, "thread ", 1, &cmdlist);
740
741 add_prefix_cmd ("apply", class_run, thread_apply_command,
742 "Apply a command to a list of threads.",
743 &thread_apply_list, "apply ", 1, &thread_cmd_list);
744
745 add_cmd ("all", class_run, thread_apply_all_command,
746 "Apply a command to all threads.", &thread_apply_list);
747
748 if (!xdb_commands)
749 add_com_alias ("t", "thread", class_run, 1);
750 }
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