1 /* libthread_db assisted debugging support, generic parts.
3 Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
25 #include "gdb_assert.h"
27 #include "gdb_proc_service.h"
28 #include "gdb_thread_db.h"
31 #include "exceptions.h"
32 #include "gdbthread.h"
38 #include "solib-svr4.h"
40 #include "linux-nat.h"
44 #ifdef HAVE_GNU_LIBC_VERSION_H
45 #include <gnu/libc-version.h>
48 #ifndef LIBTHREAD_DB_SO
49 #define LIBTHREAD_DB_SO "libthread_db.so.1"
52 /* If we're running on GNU/Linux, we must explicitly attach to any new
55 /* FIXME: There is certainly some room for improvements:
57 - Bypass libthread_db when fetching or storing registers for
58 threads bound to a LWP. */
60 /* This module's target vector. */
61 static struct target_ops thread_db_ops
;
63 /* The target vector that we call for things this module can't handle. */
64 static struct target_ops
*target_beneath
;
66 /* Pointer to the next function on the objfile event chain. */
67 static void (*target_new_objfile_chain
) (struct objfile
* objfile
);
69 /* Non-zero if we're using this module's target vector. */
70 static int using_thread_db
;
72 /* Non-zero if we have determined the signals used by the threads
74 static int thread_signals
;
75 static sigset_t thread_stop_set
;
76 static sigset_t thread_print_set
;
78 /* Structure that identifies the child process for the
79 <proc_service.h> interface. */
80 static struct ps_prochandle proc_handle
;
82 /* Connection to the libthread_db library. */
83 static td_thragent_t
*thread_agent
;
85 /* Pointers to the libthread_db functions. */
87 static td_err_e (*td_init_p
) (void);
89 static td_err_e (*td_ta_new_p
) (struct ps_prochandle
* ps
,
91 static td_err_e (*td_ta_map_id2thr_p
) (const td_thragent_t
*ta
, thread_t pt
,
92 td_thrhandle_t
*__th
);
93 static td_err_e (*td_ta_map_lwp2thr_p
) (const td_thragent_t
*ta
,
94 lwpid_t lwpid
, td_thrhandle_t
*th
);
95 static td_err_e (*td_ta_thr_iter_p
) (const td_thragent_t
*ta
,
96 td_thr_iter_f
*callback
, void *cbdata_p
,
97 td_thr_state_e state
, int ti_pri
,
98 sigset_t
*ti_sigmask_p
,
99 unsigned int ti_user_flags
);
100 static td_err_e (*td_ta_event_addr_p
) (const td_thragent_t
*ta
,
101 td_event_e event
, td_notify_t
*ptr
);
102 static td_err_e (*td_ta_set_event_p
) (const td_thragent_t
*ta
,
103 td_thr_events_t
*event
);
104 static td_err_e (*td_ta_event_getmsg_p
) (const td_thragent_t
*ta
,
105 td_event_msg_t
*msg
);
107 static td_err_e (*td_thr_validate_p
) (const td_thrhandle_t
*th
);
108 static td_err_e (*td_thr_get_info_p
) (const td_thrhandle_t
*th
,
109 td_thrinfo_t
*infop
);
110 static td_err_e (*td_thr_event_enable_p
) (const td_thrhandle_t
*th
,
113 static td_err_e (*td_thr_tls_get_addr_p
) (const td_thrhandle_t
*th
,
115 size_t offset
, void **address
);
117 /* Location of the thread creation event breakpoint. The code at this
118 location in the child process will be called by the pthread library
119 whenever a new thread is created. By setting a special breakpoint
120 at this location, GDB can detect when a new thread is created. We
121 obtain this location via the td_ta_event_addr call. */
122 static CORE_ADDR td_create_bp_addr
;
124 /* Location of the thread death event breakpoint. */
125 static CORE_ADDR td_death_bp_addr
;
127 /* Prototypes for local functions. */
128 static void thread_db_find_new_threads (void);
129 static void attach_thread (ptid_t ptid
, const td_thrhandle_t
*th_p
,
130 const td_thrinfo_t
*ti_p
, int verbose
);
131 static void detach_thread (ptid_t ptid
, int verbose
);
134 /* Building process ids. */
136 #define GET_PID(ptid) ptid_get_pid (ptid)
137 #define GET_LWP(ptid) ptid_get_lwp (ptid)
138 #define GET_THREAD(ptid) ptid_get_tid (ptid)
140 #define is_lwp(ptid) (GET_LWP (ptid) != 0)
141 #define is_thread(ptid) (GET_THREAD (ptid) != 0)
143 #define BUILD_LWP(lwp, pid) ptid_build (pid, lwp, 0)
146 /* Use "struct private_thread_info" to cache thread state. This is
147 a substantial optimization. */
149 struct private_thread_info
151 /* Flag set when we see a TD_DEATH event for this thread. */
152 unsigned int dying
:1;
154 /* Cached thread state. */
155 unsigned int th_valid
:1;
156 unsigned int ti_valid
:1;
164 thread_db_err_str (td_err_e err
)
171 return "generic 'call succeeded'";
173 return "generic error";
175 return "no thread to satisfy query";
177 return "no sync handle to satisfy query";
179 return "no LWP to satisfy query";
181 return "invalid process handle";
183 return "invalid thread handle";
185 return "invalid synchronization handle";
187 return "invalid thread agent";
189 return "invalid key";
191 return "no event message for getmsg";
193 return "FPU register set not available";
195 return "application not linked with libthread";
197 return "requested event is not supported";
199 return "capability not available";
201 return "debugger service failed";
203 return "operation not applicable to";
205 return "no thread-specific data for this thread";
207 return "malloc failed";
209 return "only part of register set was written/read";
211 return "X register set not available for this thread";
212 #ifdef THREAD_DB_HAS_TD_NOTALLOC
214 return "thread has not yet allocated TLS for given module";
216 #ifdef THREAD_DB_HAS_TD_VERSION
218 return "versions of libpthread and libthread_db do not match";
220 #ifdef THREAD_DB_HAS_TD_NOTLS
222 return "there is no TLS segment in the given module";
225 snprintf (buf
, sizeof (buf
), "unknown thread_db error '%d'", err
);
230 /* A callback function for td_ta_thr_iter, which we use to map all
233 THP is a handle to the current thread; if INFOP is not NULL, the
234 struct thread_info associated with this thread is returned in
237 If the thread is a zombie, TD_THR_ZOMBIE is returned. Otherwise,
238 zero is returned to indicate success. */
241 thread_get_info_callback (const td_thrhandle_t
*thp
, void *infop
)
245 struct thread_info
*thread_info
;
248 err
= td_thr_get_info_p (thp
, &ti
);
250 error (_("thread_get_info_callback: cannot get thread info: %s"),
251 thread_db_err_str (err
));
253 /* Fill the cache. */
254 thread_ptid
= ptid_build (GET_PID (inferior_ptid
), ti
.ti_lid
, ti
.ti_tid
);
255 thread_info
= find_thread_pid (thread_ptid
);
257 /* In the case of a zombie thread, don't continue. We don't want to
258 attach to it thinking it is a new thread. */
259 if (ti
.ti_state
== TD_THR_UNKNOWN
|| ti
.ti_state
== TD_THR_ZOMBIE
)
262 *(struct thread_info
**) infop
= thread_info
;
263 if (thread_info
!= NULL
)
265 memcpy (&thread_info
->private->th
, thp
, sizeof (*thp
));
266 thread_info
->private->th_valid
= 1;
267 memcpy (&thread_info
->private->ti
, &ti
, sizeof (ti
));
268 thread_info
->private->ti_valid
= 1;
270 return TD_THR_ZOMBIE
;
273 if (thread_info
== NULL
)
275 /* New thread. Attach to it now (why wait?). */
276 attach_thread (thread_ptid
, thp
, &ti
, 1);
277 thread_info
= find_thread_pid (thread_ptid
);
278 gdb_assert (thread_info
!= NULL
);
281 memcpy (&thread_info
->private->th
, thp
, sizeof (*thp
));
282 thread_info
->private->th_valid
= 1;
283 memcpy (&thread_info
->private->ti
, &ti
, sizeof (ti
));
284 thread_info
->private->ti_valid
= 1;
287 *(struct thread_info
**) infop
= thread_info
;
292 /* Accessor functions for the thread_db information, with caching. */
295 thread_db_map_id2thr (struct thread_info
*thread_info
, int fatal
)
299 if (thread_info
->private->th_valid
)
302 err
= td_ta_map_id2thr_p (thread_agent
, GET_THREAD (thread_info
->ptid
),
303 &thread_info
->private->th
);
307 error (_("Cannot find thread %ld: %s"),
308 (long) GET_THREAD (thread_info
->ptid
),
309 thread_db_err_str (err
));
312 thread_info
->private->th_valid
= 1;
315 /* Convert between user-level thread ids and LWP ids. */
318 thread_from_lwp (ptid_t ptid
)
322 struct thread_info
*thread_info
;
325 if (GET_LWP (ptid
) == 0)
326 ptid
= BUILD_LWP (GET_PID (ptid
), GET_PID (ptid
));
328 gdb_assert (is_lwp (ptid
));
330 err
= td_ta_map_lwp2thr_p (thread_agent
, GET_LWP (ptid
), &th
);
332 error (_("Cannot find user-level thread for LWP %ld: %s"),
333 GET_LWP (ptid
), thread_db_err_str (err
));
337 /* Fetch the thread info. If we get back TD_THR_ZOMBIE, then the
338 event thread has already died. If another gdb interface has called
339 thread_alive() previously, the thread won't be found on the thread list
340 anymore. In that case, we don't want to process this ptid anymore
341 to avoid the possibility of later treating it as a newly
342 discovered thread id that we should add to the list. Thus,
343 we return a -1 ptid which is also how the thread list marks a
345 if (thread_get_info_callback (&th
, &thread_info
) == TD_THR_ZOMBIE
346 && thread_info
== NULL
)
347 return pid_to_ptid (-1);
349 gdb_assert (thread_info
&& thread_info
->private->ti_valid
);
351 return ptid_build (GET_PID (ptid
), GET_LWP (ptid
),
352 thread_info
->private->ti
.ti_tid
);
356 lwp_from_thread (ptid_t ptid
)
358 return BUILD_LWP (GET_LWP (ptid
), GET_PID (ptid
));
363 thread_db_init (struct target_ops
*target
)
365 target_beneath
= target
;
369 verbose_dlsym (void *handle
, const char *name
)
371 void *sym
= dlsym (handle
, name
);
373 warning (_("Symbol \"%s\" not found in libthread_db: %s"), name
, dlerror ());
378 thread_db_load (void)
383 handle
= dlopen (LIBTHREAD_DB_SO
, RTLD_NOW
);
386 fprintf_filtered (gdb_stderr
, "\n\ndlopen failed on '%s' - %s\n",
387 LIBTHREAD_DB_SO
, dlerror ());
388 fprintf_filtered (gdb_stderr
,
389 "GDB will not be able to debug pthreads.\n\n");
393 /* Initialize pointers to the dynamic library functions we will use.
394 Essential functions first. */
396 td_init_p
= verbose_dlsym (handle
, "td_init");
397 if (td_init_p
== NULL
)
400 td_ta_new_p
= verbose_dlsym (handle
, "td_ta_new");
401 if (td_ta_new_p
== NULL
)
404 td_ta_map_id2thr_p
= verbose_dlsym (handle
, "td_ta_map_id2thr");
405 if (td_ta_map_id2thr_p
== NULL
)
408 td_ta_map_lwp2thr_p
= verbose_dlsym (handle
, "td_ta_map_lwp2thr");
409 if (td_ta_map_lwp2thr_p
== NULL
)
412 td_ta_thr_iter_p
= verbose_dlsym (handle
, "td_ta_thr_iter");
413 if (td_ta_thr_iter_p
== NULL
)
416 td_thr_validate_p
= verbose_dlsym (handle
, "td_thr_validate");
417 if (td_thr_validate_p
== NULL
)
420 td_thr_get_info_p
= verbose_dlsym (handle
, "td_thr_get_info");
421 if (td_thr_get_info_p
== NULL
)
424 /* Initialize the library. */
428 warning (_("Cannot initialize libthread_db: %s"), thread_db_err_str (err
));
432 /* These are not essential. */
433 td_ta_event_addr_p
= dlsym (handle
, "td_ta_event_addr");
434 td_ta_set_event_p
= dlsym (handle
, "td_ta_set_event");
435 td_ta_event_getmsg_p
= dlsym (handle
, "td_ta_event_getmsg");
436 td_thr_event_enable_p
= dlsym (handle
, "td_thr_event_enable");
437 td_thr_tls_get_addr_p
= dlsym (handle
, "td_thr_tls_get_addr");
443 enable_thread_event (td_thragent_t
*thread_agent
, int event
, CORE_ADDR
*bp
)
448 /* Get the breakpoint address for thread EVENT. */
449 err
= td_ta_event_addr_p (thread_agent
, event
, ¬ify
);
453 /* Set up the breakpoint. */
454 gdb_assert (exec_bfd
);
455 (*bp
) = (gdbarch_convert_from_func_ptr_addr
457 /* Do proper sign extension for the target. */
458 (bfd_get_sign_extend_vma (exec_bfd
) > 0
459 ? (CORE_ADDR
) (intptr_t) notify
.u
.bptaddr
460 : (CORE_ADDR
) (uintptr_t) notify
.u
.bptaddr
),
462 create_thread_event_breakpoint ((*bp
));
468 enable_thread_event_reporting (void)
470 td_thr_events_t events
;
473 #ifdef HAVE_GNU_LIBC_VERSION_H
474 const char *libc_version
;
475 int libc_major
, libc_minor
;
478 /* We cannot use the thread event reporting facility if these
479 functions aren't available. */
480 if (td_ta_event_addr_p
== NULL
|| td_ta_set_event_p
== NULL
481 || td_ta_event_getmsg_p
== NULL
|| td_thr_event_enable_p
== NULL
)
484 /* Set the process wide mask saying which events we're interested in. */
485 td_event_emptyset (&events
);
486 td_event_addset (&events
, TD_CREATE
);
488 #ifdef HAVE_GNU_LIBC_VERSION_H
489 /* FIXME: kettenis/2000-04-23: The event reporting facility is
490 broken for TD_DEATH events in glibc 2.1.3, so don't enable it for
492 libc_version
= gnu_get_libc_version ();
493 if (sscanf (libc_version
, "%d.%d", &libc_major
, &libc_minor
) == 2
494 && (libc_major
> 2 || (libc_major
== 2 && libc_minor
> 1)))
496 td_event_addset (&events
, TD_DEATH
);
498 err
= td_ta_set_event_p (thread_agent
, &events
);
501 warning (_("Unable to set global thread event mask: %s"),
502 thread_db_err_str (err
));
506 /* Delete previous thread event breakpoints, if any. */
507 remove_thread_event_breakpoints ();
508 td_create_bp_addr
= 0;
509 td_death_bp_addr
= 0;
511 /* Set up the thread creation event. */
512 err
= enable_thread_event (thread_agent
, TD_CREATE
, &td_create_bp_addr
);
515 warning (_("Unable to get location for thread creation breakpoint: %s"),
516 thread_db_err_str (err
));
520 /* Set up the thread death event. */
521 err
= enable_thread_event (thread_agent
, TD_DEATH
, &td_death_bp_addr
);
524 warning (_("Unable to get location for thread death breakpoint: %s"),
525 thread_db_err_str (err
));
531 disable_thread_event_reporting (void)
533 td_thr_events_t events
;
535 /* Set the process wide mask saying we aren't interested in any
537 td_event_emptyset (&events
);
538 td_ta_set_event_p (thread_agent
, &events
);
540 /* Delete thread event breakpoints, if any. */
541 remove_thread_event_breakpoints ();
542 td_create_bp_addr
= 0;
543 td_death_bp_addr
= 0;
547 check_thread_signals (void)
549 #ifdef GET_THREAD_SIGNALS
555 GET_THREAD_SIGNALS (&mask
);
556 sigemptyset (&thread_stop_set
);
557 sigemptyset (&thread_print_set
);
559 for (i
= 1; i
< NSIG
; i
++)
561 if (sigismember (&mask
, i
))
563 if (signal_stop_update (target_signal_from_host (i
), 0))
564 sigaddset (&thread_stop_set
, i
);
565 if (signal_print_update (target_signal_from_host (i
), 0))
566 sigaddset (&thread_print_set
, i
);
574 /* Check whether thread_db is usable. This function is called when
575 an inferior is created (or otherwise acquired, e.g. attached to)
576 and when new shared libraries are loaded into a running process. */
579 check_for_thread_db (void)
582 static int already_loaded
;
584 /* First time through, report that libthread_db was successfuly
585 loaded. Can't print this in in thread_db_load as, at that stage,
586 the interpreter and it's console haven't started. */
591 const char *library
= NULL
;
592 if (dladdr ((*td_ta_new_p
), &info
) != 0)
593 library
= info
.dli_fname
;
598 /* Paranoid - don't let a NULL path slip through. */
599 library
= LIBTHREAD_DB_SO
;
601 printf_unfiltered (_("Using host libthread_db library \"%s\".\n"),
607 /* Nothing to do. The thread library was already detected and the
608 target vector was already activated. */
611 /* Don't attempt to use thread_db on targets which can not run
612 (executables not running yet, core files) for now. */
613 if (!target_has_execution
)
616 /* Don't attempt to use thread_db for remote targets. */
617 if (!target_can_run (¤t_target
))
620 /* Initialize the structure that identifies the child process. */
621 proc_handle
.pid
= GET_PID (inferior_ptid
);
623 /* Now attempt to open a connection to the thread library. */
624 err
= td_ta_new_p (&proc_handle
, &thread_agent
);
628 /* No thread library was detected. */
632 printf_unfiltered (_("[Thread debugging using libthread_db enabled]\n"));
634 /* The thread library was detected. Activate the thread_db target. */
635 push_target (&thread_db_ops
);
638 enable_thread_event_reporting ();
639 thread_db_find_new_threads ();
643 warning (_("Cannot initialize thread debugging library: %s"),
644 thread_db_err_str (err
));
650 thread_db_new_objfile (struct objfile
*objfile
)
653 check_for_thread_db ();
655 if (target_new_objfile_chain
)
656 target_new_objfile_chain (objfile
);
659 /* Attach to a new thread. This function is called when we receive a
660 TD_CREATE event or when we iterate over all threads and find one
661 that wasn't already in our list. */
664 attach_thread (ptid_t ptid
, const td_thrhandle_t
*th_p
,
665 const td_thrinfo_t
*ti_p
, int verbose
)
667 struct thread_info
*tp
;
670 /* If we're being called after a TD_CREATE event, we may already
671 know about this thread. There are two ways this can happen. We
672 may have iterated over all threads between the thread creation
673 and the TD_CREATE event, for instance when the user has issued
674 the `info threads' command before the SIGTRAP for hitting the
675 thread creation breakpoint was reported. Alternatively, the
676 thread may have exited and a new one been created with the same
677 thread ID. In the first case we don't need to do anything; in
678 the second case we should discard information about the dead
679 thread and attach to the new one. */
680 if (in_thread_list (ptid
))
682 tp
= find_thread_pid (ptid
);
683 gdb_assert (tp
!= NULL
);
685 if (!tp
->private->dying
)
688 delete_thread (ptid
);
691 check_thread_signals ();
693 if (ti_p
->ti_state
== TD_THR_UNKNOWN
|| ti_p
->ti_state
== TD_THR_ZOMBIE
)
694 return; /* A zombie thread -- do not attach. */
696 /* Under GNU/Linux, we have to attach to each and every thread. */
697 if (lin_lwp_attach_lwp (BUILD_LWP (ti_p
->ti_lid
, GET_PID (ptid
)), 0) < 0)
700 /* Add the thread to GDB's thread list. */
701 tp
= add_thread (ptid
);
702 tp
->private = xmalloc (sizeof (struct private_thread_info
));
703 memset (tp
->private, 0, sizeof (struct private_thread_info
));
706 printf_unfiltered (_("[New %s]\n"), target_pid_to_str (ptid
));
708 /* Enable thread event reporting for this thread. */
709 err
= td_thr_event_enable_p (th_p
, 1);
711 error (_("Cannot enable thread event reporting for %s: %s"),
712 target_pid_to_str (ptid
), thread_db_err_str (err
));
716 thread_db_attach (char *args
, int from_tty
)
718 target_beneath
->to_attach (args
, from_tty
);
720 /* Destroy thread info; it's no longer valid. */
723 /* The child process is now the actual multi-threaded
724 program. Snatch its process ID... */
725 proc_handle
.pid
= GET_PID (inferior_ptid
);
727 /* ...and perform the remaining initialization steps. */
728 enable_thread_event_reporting ();
729 thread_db_find_new_threads ();
733 detach_thread (ptid_t ptid
, int verbose
)
735 struct thread_info
*thread_info
;
738 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (ptid
));
740 /* Don't delete the thread now, because it still reports as active
741 until it has executed a few instructions after the event
742 breakpoint - if we deleted it now, "info threads" would cause us
743 to re-attach to it. Just mark it as having had a TD_DEATH
744 event. This means that we won't delete it from our thread list
745 until we notice that it's dead (via prune_threads), or until
746 something re-uses its thread ID. */
747 thread_info
= find_thread_pid (ptid
);
748 gdb_assert (thread_info
!= NULL
);
749 thread_info
->private->dying
= 1;
753 thread_db_detach (char *args
, int from_tty
)
755 disable_thread_event_reporting ();
757 /* There's no need to save & restore inferior_ptid here, since the
758 inferior is supposed to be survive this function call. */
759 inferior_ptid
= lwp_from_thread (inferior_ptid
);
761 /* Forget about the child's process ID. We shouldn't need it
765 target_beneath
->to_detach (args
, from_tty
);
769 clear_lwpid_callback (struct thread_info
*thread
, void *dummy
)
771 /* If we know that our thread implementation is 1-to-1, we could save
772 a certain amount of information; it's not clear how much, so we
773 are always conservative. */
775 thread
->private->th_valid
= 0;
776 thread
->private->ti_valid
= 0;
782 thread_db_resume (ptid_t ptid
, int step
, enum target_signal signo
)
784 struct cleanup
*old_chain
= save_inferior_ptid ();
786 if (GET_PID (ptid
) == -1)
787 inferior_ptid
= lwp_from_thread (inferior_ptid
);
788 else if (is_thread (ptid
))
789 ptid
= lwp_from_thread (ptid
);
791 /* Clear cached data which may not be valid after the resume. */
792 iterate_over_threads (clear_lwpid_callback
, NULL
);
794 target_beneath
->to_resume (ptid
, step
, signo
);
796 do_cleanups (old_chain
);
799 /* Check if PID is currently stopped at the location of a thread event
800 breakpoint location. If it is, read the event message and act upon
804 check_event (ptid_t ptid
)
812 /* Bail out early if we're not at a thread event breakpoint. */
813 stop_pc
= read_pc_pid (ptid
) - DECR_PC_AFTER_BREAK
;
814 if (stop_pc
!= td_create_bp_addr
&& stop_pc
!= td_death_bp_addr
)
817 /* If we are at a create breakpoint, we do not know what new lwp
818 was created and cannot specifically locate the event message for it.
819 We have to call td_ta_event_getmsg() to get
820 the latest message. Since we have no way of correlating whether
821 the event message we get back corresponds to our breakpoint, we must
822 loop and read all event messages, processing them appropriately.
823 This guarantees we will process the correct message before continuing
826 Currently, death events are not enabled. If they are enabled,
827 the death event can use the td_thr_event_getmsg() interface to
828 get the message specifically for that lwp and avoid looping
835 err
= td_ta_event_getmsg_p (thread_agent
, &msg
);
841 error (_("Cannot get thread event message: %s"),
842 thread_db_err_str (err
));
845 err
= td_thr_get_info_p (msg
.th_p
, &ti
);
847 error (_("Cannot get thread info: %s"), thread_db_err_str (err
));
849 ptid
= ptid_build (GET_PID (ptid
), ti
.ti_lid
, ti
.ti_tid
);
854 /* Call attach_thread whether or not we already know about a
855 thread with this thread ID. */
856 attach_thread (ptid
, msg
.th_p
, &ti
, 1);
862 if (!in_thread_list (ptid
))
863 error (_("Spurious thread death event."));
865 detach_thread (ptid
, 1);
870 error (_("Spurious thread event."));
877 thread_db_wait (ptid_t ptid
, struct target_waitstatus
*ourstatus
)
879 extern ptid_t trap_ptid
;
881 if (GET_PID (ptid
) != -1 && is_thread (ptid
))
882 ptid
= lwp_from_thread (ptid
);
884 ptid
= target_beneath
->to_wait (ptid
, ourstatus
);
886 if (proc_handle
.pid
== 0)
887 /* The current child process isn't the actual multi-threaded
888 program yet, so don't try to do any special thread-specific
889 post-processing and bail out early. */
892 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
893 || ourstatus
->kind
== TARGET_WAITKIND_SIGNALLED
)
894 return pid_to_ptid (-1);
896 if (ourstatus
->kind
== TARGET_WAITKIND_EXECD
)
898 remove_thread_event_breakpoints ();
899 unpush_target (&thread_db_ops
);
902 return pid_to_ptid (GET_PID (ptid
));
905 if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
906 && ourstatus
->value
.sig
== TARGET_SIGNAL_TRAP
)
907 /* Check for a thread event. */
910 if (!ptid_equal (trap_ptid
, null_ptid
))
911 trap_ptid
= thread_from_lwp (trap_ptid
);
913 /* Change the ptid back into the higher level PID + TID format.
914 If the thread is dead and no longer on the thread list, we will
915 get back a dead ptid. This can occur if the thread death event
916 gets postponed by other simultaneous events. In such a case,
917 we want to just ignore the event and continue on. */
918 ptid
= thread_from_lwp (ptid
);
919 if (GET_PID (ptid
) == -1)
920 ourstatus
->kind
= TARGET_WAITKIND_SPURIOUS
;
926 thread_db_xfer_partial (struct target_ops
*ops
, enum target_object object
,
927 const char *annex
, gdb_byte
*readbuf
,
928 const gdb_byte
*writebuf
, ULONGEST offset
, LONGEST len
)
930 struct cleanup
*old_chain
= save_inferior_ptid ();
933 if (is_thread (inferior_ptid
))
935 /* FIXME: This seems to be necessary to make sure breakpoints
937 if (!target_thread_alive (inferior_ptid
))
938 inferior_ptid
= pid_to_ptid (GET_PID (inferior_ptid
));
940 inferior_ptid
= lwp_from_thread (inferior_ptid
);
943 xfer
= target_beneath
->to_xfer_partial (ops
, object
, annex
,
944 readbuf
, writebuf
, offset
, len
);
946 do_cleanups (old_chain
);
951 thread_db_kill (void)
953 /* There's no need to save & restore inferior_ptid here, since the
954 inferior isn't supposed to survive this function call. */
955 inferior_ptid
= lwp_from_thread (inferior_ptid
);
956 target_beneath
->to_kill ();
960 thread_db_create_inferior (char *exec_file
, char *allargs
, char **env
,
963 unpush_target (&thread_db_ops
);
965 target_beneath
->to_create_inferior (exec_file
, allargs
, env
, from_tty
);
969 thread_db_post_startup_inferior (ptid_t ptid
)
971 if (proc_handle
.pid
== 0)
973 /* The child process is now the actual multi-threaded
974 program. Snatch its process ID... */
975 proc_handle
.pid
= GET_PID (ptid
);
977 /* ...and perform the remaining initialization steps. */
978 enable_thread_event_reporting ();
979 thread_db_find_new_threads ();
984 thread_db_mourn_inferior (void)
986 /* Forget about the child's process ID. We shouldn't need it
990 target_beneath
->to_mourn_inferior ();
992 /* Delete the old thread event breakpoints. Do this after mourning
993 the inferior, so that we don't try to uninsert them. */
994 remove_thread_event_breakpoints ();
996 /* Detach thread_db target ops. */
997 unpush_target (&thread_db_ops
);
1002 find_new_threads_callback (const td_thrhandle_t
*th_p
, void *data
)
1008 err
= td_thr_get_info_p (th_p
, &ti
);
1010 error (_("find_new_threads_callback: cannot get thread info: %s"),
1011 thread_db_err_str (err
));
1013 if (ti
.ti_state
== TD_THR_UNKNOWN
|| ti
.ti_state
== TD_THR_ZOMBIE
)
1014 return 0; /* A zombie -- ignore. */
1016 ptid
= ptid_build (GET_PID (inferior_ptid
), ti
.ti_lid
, ti
.ti_tid
);
1018 if (!in_thread_list (ptid
))
1019 attach_thread (ptid
, th_p
, &ti
, 1);
1025 thread_db_find_new_threads (void)
1029 /* Iterate over all user-space threads to discover new threads. */
1030 err
= td_ta_thr_iter_p (thread_agent
, find_new_threads_callback
, NULL
,
1031 TD_THR_ANY_STATE
, TD_THR_LOWEST_PRIORITY
,
1032 TD_SIGNO_MASK
, TD_THR_ANY_USER_FLAGS
);
1034 error (_("Cannot find new threads: %s"), thread_db_err_str (err
));
1038 thread_db_pid_to_str (ptid_t ptid
)
1040 if (is_thread (ptid
))
1042 static char buf
[64];
1043 struct thread_info
*thread_info
;
1045 thread_info
= find_thread_pid (ptid
);
1046 if (thread_info
== NULL
)
1047 snprintf (buf
, sizeof (buf
), "Thread %ld (LWP %ld) (Missing)",
1048 GET_THREAD (ptid
), GET_LWP (ptid
));
1050 snprintf (buf
, sizeof (buf
), "Thread %ld (LWP %ld)",
1051 GET_THREAD (ptid
), GET_LWP (ptid
));
1056 if (target_beneath
->to_pid_to_str (ptid
))
1057 return target_beneath
->to_pid_to_str (ptid
);
1059 return normal_pid_to_str (ptid
);
1062 /* Return a string describing the state of the thread specified by
1066 thread_db_extra_thread_info (struct thread_info
*info
)
1068 if (info
->private->dying
)
1074 /* Get the address of the thread local variable in load module LM which
1075 is stored at OFFSET within the thread local storage for thread PTID. */
1078 thread_db_get_thread_local_address (ptid_t ptid
,
1082 if (is_thread (ptid
))
1086 struct thread_info
*thread_info
;
1088 /* glibc doesn't provide the needed interface. */
1089 if (!td_thr_tls_get_addr_p
)
1090 throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR
,
1091 _("No TLS library support"));
1093 /* Caller should have verified that lm != 0. */
1094 gdb_assert (lm
!= 0);
1096 /* Get info about the thread. */
1097 thread_info
= find_thread_pid (ptid
);
1098 thread_db_map_id2thr (thread_info
, 1);
1100 /* Finally, get the address of the variable. */
1101 err
= td_thr_tls_get_addr_p (&thread_info
->private->th
,
1102 (void *)(size_t) lm
,
1105 #ifdef THREAD_DB_HAS_TD_NOTALLOC
1106 /* The memory hasn't been allocated, yet. */
1107 if (err
== TD_NOTALLOC
)
1108 /* Now, if libthread_db provided the initialization image's
1109 address, we *could* try to build a non-lvalue value from
1110 the initialization image. */
1111 throw_error (TLS_NOT_ALLOCATED_YET_ERROR
,
1112 _("TLS not allocated yet"));
1115 /* Something else went wrong. */
1117 throw_error (TLS_GENERIC_ERROR
,
1118 (("%s")), thread_db_err_str (err
));
1120 /* Cast assuming host == target. Joy. */
1121 /* Do proper sign extension for the target. */
1122 gdb_assert (exec_bfd
);
1123 return (bfd_get_sign_extend_vma (exec_bfd
) > 0
1124 ? (CORE_ADDR
) (intptr_t) address
1125 : (CORE_ADDR
) (uintptr_t) address
);
1128 if (target_beneath
->to_get_thread_local_address
)
1129 return target_beneath
->to_get_thread_local_address (ptid
, lm
, offset
);
1131 throw_error (TLS_GENERIC_ERROR
,
1132 _("TLS not supported on this target"));
1136 init_thread_db_ops (void)
1138 thread_db_ops
.to_shortname
= "multi-thread";
1139 thread_db_ops
.to_longname
= "multi-threaded child process.";
1140 thread_db_ops
.to_doc
= "Threads and pthreads support.";
1141 thread_db_ops
.to_attach
= thread_db_attach
;
1142 thread_db_ops
.to_detach
= thread_db_detach
;
1143 thread_db_ops
.to_resume
= thread_db_resume
;
1144 thread_db_ops
.to_wait
= thread_db_wait
;
1145 thread_db_ops
.to_xfer_partial
= thread_db_xfer_partial
;
1146 thread_db_ops
.to_kill
= thread_db_kill
;
1147 thread_db_ops
.to_create_inferior
= thread_db_create_inferior
;
1148 thread_db_ops
.to_post_startup_inferior
= thread_db_post_startup_inferior
;
1149 thread_db_ops
.to_mourn_inferior
= thread_db_mourn_inferior
;
1150 thread_db_ops
.to_find_new_threads
= thread_db_find_new_threads
;
1151 thread_db_ops
.to_pid_to_str
= thread_db_pid_to_str
;
1152 thread_db_ops
.to_stratum
= thread_stratum
;
1153 thread_db_ops
.to_has_thread_control
= tc_schedlock
;
1154 thread_db_ops
.to_get_thread_local_address
1155 = thread_db_get_thread_local_address
;
1156 thread_db_ops
.to_extra_thread_info
= thread_db_extra_thread_info
;
1157 thread_db_ops
.to_magic
= OPS_MAGIC
;
1161 _initialize_thread_db (void)
1163 /* Only initialize the module if we can load libthread_db. */
1164 if (thread_db_load ())
1166 init_thread_db_ops ();
1167 add_target (&thread_db_ops
);
1169 /* Add ourselves to objfile event chain. */
1170 target_new_objfile_chain
= deprecated_target_new_objfile_hook
;
1171 deprecated_target_new_objfile_hook
= thread_db_new_objfile
;