1 /* Low level interface for debugging UnixWare user-mode threads for
4 Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
5 Written by Nick Duffek <nsd@cygnus.com>.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
25 /* Like many systems, UnixWare implements two classes of threads:
26 kernel-mode threads, which are scheduled by the kernel; and
27 user-mode threads, which are scheduled by a library. UnixWare
28 calls these two classes lightweight processes (LWPs) and threads,
31 This module deals with user-mode threads. It calls procfs_ops
32 functions to deal with LWPs and processes and core_ops functions to
35 As of this writing, the user-mode thread debugging interface is not
36 documented beyond the comments in <thread.h>. The following
37 description has been gleaned from experience and from information
40 libthread.so, against which all UnixWare user-mode thread programs
41 link, provides a global thread_debug structure named _thr_debug.
44 (1) thr_map is a pointer to a pointer to an element of a
45 thread_map ring. A thread_map contains a single thread's id
46 number, state, LWP pointer, recent register state, and other
49 (2) thr_brk is a pointer to a stub function that libthread.so
50 calls when it changes a thread's state, e.g. by creating it,
51 switching it to an LWP, or causing it to exit.
53 (3) thr_debug_on controls whether libthread.so calls thr_brk().
55 Debuggers are able to track thread activity by setting a private
56 breakpoint on thr_brk() and setting thr_debug_on to 1.
58 thr_brk() receives two arguments:
60 (1) a pointer to a thread_map describing the thread being
63 (2) an enum thread_change specifying one of the following
67 thread_create thread has just been created
68 thread_exit thread has just exited
69 switch_begin thread will be switched to an LWP
70 switch_complete thread has been switched to an LWP
71 cancel_complete thread wasn't switched to an LWP
72 thread_suspend thread has been thr_suspend()ed
73 thread_suspend_pending thread will be thr_suspend()ed
74 thread_continue thread has been thr_continue()d
76 The thread_map argument to thr_brk() is NULL under the following
79 - The main thread is being acted upon. The main thread always
80 has id 1, so its thread_map is easy to find by scanning through
83 - A "switch_complete" change is occurring, which means that the
84 thread specified in the most recent "switch_begin" change has
87 - A "cancel_complete" change is occurring, which means that the
88 thread specified in the most recent "switch_begin" change has
89 not moved to an LWP after all.
91 - A spurious "switch_begin" change is occurring after a
94 Between switch_begin and switch_complete or cancel_complete, the
95 affected thread's LWP pointer is not reliable. It is possible that
96 other parts of the thread's thread_map are also unreliable during
101 #include "gdbthread.h"
103 #include "inferior.h"
104 #include "regcache.h"
107 /* <thread.h> includes <sys/priocntl.h>, which requires boolean_t from
108 <sys/types.h>, which doesn't typedef boolean_t with gcc. */
110 #define boolean_t int
114 #include <synch.h> /* for UnixWare 2.x */
116 /* Prototypes for supply_gregset etc. */
119 /* Whether to emit debugging output. */
123 /* Default debugging output file, overridden by envvar UWTHR_DEBUG. */
125 #define DEBUG_FILE "/dev/tty"
127 /* #if DEBUG, write string S to the debugging output channel. */
130 # define DBG(fmt_and_args)
131 # define DBG2(fmt_and_args)
133 # define DBG(fmt_and_args) dbg fmt_and_args
134 # define DBG2(fmt_and_args)
137 /* Back end to CALL_BASE() and TRY_BASE(): evaluate CALL, then convert
138 inferior_ptid to a composite thread/process id. */
140 #define CALL_BASE_1(call) \
142 DBG2(("CALL_BASE(" #call ")")); \
144 do_cleanups (infpid_cleanup); \
147 /* If inferior_ptid can be converted to a composite lwp/process id, do so,
148 evaluate base_ops function CALL, and then convert inferior_ptid back to a
149 composite thread/process id.
151 Otherwise, issue an error message and return nonlocally. */
153 #define CALL_BASE(call) \
155 if (!lwp_infpid ()) \
156 error ("uw-thread: no lwp"); \
157 CALL_BASE_1 (call); \
160 /* Like CALL_BASE(), but instead of returning nonlocally on error, set
161 *CALLED to whether the inferior_ptid conversion was successful. */
163 #define TRY_BASE(call, called) \
165 if ((*(called) = lwp_infpid ())) \
166 CALL_BASE_1 (call); \
169 /* Information passed by thread_iter() to its callback parameter. */
172 struct thread_map map
;
177 /* Private thread data for the thread_info struct. */
179 struct private_thread_info
{
180 int stable
; /* 0 if libthread.so is modifying thread map */
181 int thrid
; /* thread id assigned by libthread.so */
182 int lwpid
; /* thread's lwp if .stable, 0 means no lwp */
183 CORE_ADDR mapp
; /* address of thread's map structure */
187 /* procfs.c's target-specific operations. */
188 extern struct target_ops procfs_ops
;
190 /* Flag to prevent procfs.c from starting inferior processes. */
191 extern int procfs_suppress_run
;
193 /* This module's target-specific operations. */
194 static struct target_ops uw_thread_ops
;
196 /* Copy of the target over which uw_thread_ops is pushed. This is
197 more convenient than a pointer to procfs_ops or core_ops, because
198 they lack current_target's default callbacks. */
199 static struct target_ops base_ops
;
201 /* Saved pointer to previous owner of target_new_objfile_hook. */
202 static void (*target_new_objfile_chain
)(struct objfile
*);
204 /* Whether we are debugging a user-space thread program. This isn't
205 set until after libthread.so is loaded by the program being
208 Except for module one-time intialization and where otherwise
209 documented, no functions in this module get called when
210 !uw_thread_active. */
211 static int uw_thread_active
;
213 /* For efficiency, cache the addresses of libthread.so's _thr_debug
214 structure, its thr_brk stub function, and the main thread's map. */
215 static CORE_ADDR thr_debug_addr
;
216 static CORE_ADDR thr_brk_addr
;
217 static CORE_ADDR thr_map_main
;
219 /* Remember the thread most recently marked as switching. Necessary because
220 libthread.so passes null map when calling stub with tc_*_complete. */
221 static struct thread_info
*switchto_thread
;
223 /* Cleanup chain for safely restoring inferior_ptid after CALL_BASE. */
224 static struct cleanup
*infpid_cleanup
;
228 /* Helper function for DBG() macro: if printf-style FMT is non-null, format it
229 with args and display the result on the debugging output channel. */
234 static int fd
= -1, len
;
244 path
= getenv ("UWTHR_DEBUG");
247 if ((fd
= open (path
, O_WRONLY
| O_CREAT
| O_TRUNC
, 0664)) < 0)
248 error ("can't open %s\n", path
);
251 va_start (args
, fmt
);
252 vsprintf (buf
, fmt
, args
);
257 (void)write (fd
, buf
, len
+ 1);
261 /* Return a string representing composite PID's components. */
266 static char *buf
, buf1
[80], buf2
[80];
267 if (!buf
|| buf
== buf2
)
272 if (PIDGET (ptid
) <= 0)
273 sprintf (buf
, "%d", PIDGET (ptid
));
275 sprintf (buf
, "%s %ld/%d", ISTID (pid
) ? "thr" : "lwp",
276 TIDGET (pid
), PIDGET (pid
));
281 /* Return a string representing thread state CHANGE. */
284 dbgchange (enum thread_change change
)
287 case tc_invalid
: return "invalid";
288 case tc_thread_create
: return "thread_create";
289 case tc_thread_exit
: return "thread_exit";
290 case tc_switch_begin
: return "switch_begin";
291 case tc_switch_complete
: return "switch_complete";
292 case tc_cancel_complete
: return "cancel_complete";
293 case tc_thread_suspend
: return "thread_suspend";
294 case tc_thread_suspend_pending
: return "thread_suspend_pending";
295 case tc_thread_continue
: return "thread_continue";
296 default: return "unknown";
300 /* Return a string representing thread STATE. */
306 case TS_ONPROC
: return "running";
307 case TS_SLEEP
: return "sleeping";
308 case TS_RUNNABLE
: return "runnable";
309 case TS_ZOMBIE
: return "zombie";
310 case TS_SUSPENDED
: return "suspended";
312 case TS_FORK
: return "forking";
314 default: return "confused";
321 /* Read the contents of _thr_debug into *DEBUGP. Return success. */
324 read_thr_debug (struct thread_debug
*debugp
)
326 return base_ops
.to_xfer_memory (thr_debug_addr
, (char *)debugp
,
327 sizeof (*debugp
), 0, NULL
, &base_ops
);
330 /* Read into MAP the contents of the thread map at inferior process address
331 MAPP. Return success. */
334 read_map (CORE_ADDR mapp
, struct thread_map
*map
)
336 return base_ops
.to_xfer_memory ((CORE_ADDR
)THR_MAP (mapp
), (char *)map
,
337 sizeof (*map
), 0, NULL
, &base_ops
);
340 /* Read into LWP the contents of the lwp decriptor at inferior process address
341 LWPP. Return success. */
344 read_lwp (CORE_ADDR lwpp
, __lwp_desc_t
*lwp
)
346 return base_ops
.to_xfer_memory (lwpp
, (char *)lwp
,
347 sizeof (*lwp
), 0, NULL
, &base_ops
);
350 /* Iterate through all user threads, applying FUNC(<map>, <lwp>, DATA) until
351 (a) FUNC returns nonzero,
352 (b) FUNC has been applied to all threads, or
354 where <map> is the thread's struct thread_map and <lwp> if non-null is the
355 thread's current __lwp_desc_t.
357 If a call to FUNC returns nonzero, return that value; otherwise, return 0. */
360 thread_iter (int (*func
)(iter_t
*, void *), void *data
)
362 struct thread_debug debug
;
363 CORE_ADDR first
, mapp
;
367 if (!read_thr_debug (&debug
))
369 if (!base_ops
.to_xfer_memory ((CORE_ADDR
)debug
.thr_map
, (char *)&mapp
,
370 sizeof (mapp
), 0, NULL
, &base_ops
))
377 if (!read_map (mapp
, &iter
.map
))
380 if (iter
.map
.thr_lwpp
)
381 if (!read_lwp ((CORE_ADDR
)iter
.map
.thr_lwpp
, &iter
.lwp
))
385 if ((ret
= func (&iter
, data
)))
388 mapp
= (CORE_ADDR
)iter
.map
.thr_next
;
394 /* Deactivate user-mode thread support. */
397 deactivate_uw_thread (void)
399 remove_thread_event_breakpoints ();
400 uw_thread_active
= 0;
401 unpush_target (&uw_thread_ops
);
404 /* Return the composite lwp/process id corresponding to composite
405 id PID. If PID is a thread with no lwp, return 0. */
408 thr_to_lwp (ptid_t ptid
)
410 struct thread_info
*info
;
415 else if (!(info
= find_thread_pid (ptid
)))
417 else if (!info
->private->lwpid
)
420 lid
= MKLID (PIDGET (ptid
), info
->private->lwpid
);
422 DBG2((" thr_to_lwp(%s) = %s", dbgpid (pid
), dbgpid (lid
)));
426 /* find_thread_lwp() callback: return whether TP describes a thread
427 associated with lwp id DATA. */
430 find_thread_lwp_callback (struct thread_info
*tp
, void *data
)
432 int lwpid
= (int)data
;
434 if (!ISTID (tp
->ptid
))
436 if (!tp
->private->stable
)
438 if (lwpid
!= tp
->private->lwpid
)
445 /* If a thread is associated with lwp id LWPID, return the corresponding
446 member of the global thread list; otherwise, return null. */
448 static struct thread_info
*
449 find_thread_lwp (int lwpid
)
451 return iterate_over_threads (find_thread_lwp_callback
, (void *)lwpid
);
454 /* Return the composite thread/process id corresponding to composite
455 id PID. If PID is an lwp with no thread, return PID. */
458 lwp_to_thr (ptid_t ptid
)
460 struct thread_info
*info
;
466 if (!(lwpid
= LIDGET (ptid
)))
468 if (!(info
= find_thread_lwp (lwpid
)))
470 tid
= MKTID (PIDGET (ptid
), info
->private->thrid
);
473 DBG2((ISTID (tid
) ? NULL
: "lwp_to_thr: no thr for %s", dbgpid (ptid
)));
477 /* do_cleanups() callback: convert inferior_ptid to a composite
478 thread/process id after having made a procfs call. */
481 thr_infpid (void *unused
)
483 ptid_t ptid
= lwp_to_thr (inferior_ptid
);
484 DBG2((" inferior_ptid from procfs: %s => %s",
485 dbgpid (inferior_ptid
), dbgpid (ptid
)));
486 inferior_ptid
= ptid
;
489 /* If possible, convert inferior_ptid to a composite lwp/process id in
490 preparation for making a procfs call. Return success. */
495 ptid_t ptid
= thr_to_lwp (inferior_ptid
);
496 DBG2((" inferior_ptid to procfs: %s => %s",
497 dbgpid (inferior_ptid
), dbgpid (ptid
)));
499 if (ptid_equal (ptid
, null_ptid
))
502 inferior_ptid
= ptid
;
503 infpid_cleanup
= make_cleanup (thr_infpid
, NULL
);
507 /* Add to the global thread list a new user-mode thread with system id THRID,
508 lwp id LWPID, map address MAPP, and composite thread/process PID. */
511 add_thread_uw (int thrid
, int lwpid
, CORE_ADDR mapp
, ptid_t ptid
)
513 struct thread_info
*newthread
;
515 if ((newthread
= add_thread (ptid
)) == NULL
)
516 error ("failed to create new thread structure");
518 newthread
->private = xmalloc (sizeof (struct private_thread_info
));
519 newthread
->private->stable
= 1;
520 newthread
->private->thrid
= thrid
;
521 newthread
->private->lwpid
= lwpid
;
522 newthread
->private->mapp
= mapp
;
524 if (target_has_execution
)
525 printf_unfiltered ("[New %s]\n", target_pid_to_str (ptid
));
528 /* notice_threads() and find_main() callback: if the thread list doesn't
529 already contain the thread described by ITER, add it if it's the main
530 thread or if !DATA. */
533 notice_thread (iter_t
*iter
, void *data
)
535 int thrid
= iter
->map
.thr_tid
;
536 int lwpid
= !iter
->map
.thr_lwpp
? 0 : iter
->lwp
.lwp_id
;
537 ptid_t ptid
= MKTID (PIDGET (inferior_ptid
), thrid
);
539 if (!find_thread_pid (ptid
) && (!data
|| thrid
== 1))
540 add_thread_uw (thrid
, lwpid
, iter
->mapp
, ptid
);
545 /* Add to the thread list any threads it doesn't already contain. */
548 notice_threads (void)
550 thread_iter (notice_thread
, NULL
);
553 /* Return the address of the main thread's map. On error, return 0. */
560 struct thread_info
*info
;
561 thread_iter (notice_thread
, (void *)1);
562 if ((info
= find_thread_pid (MKTID (PIDGET (inferior_ptid
), 1))))
563 thr_map_main
= info
->private->mapp
;
568 /* Attach to process specified by ARGS, then initialize for debugging it
569 and wait for the trace-trap that results from attaching.
571 This function only gets called with uw_thread_active == 0. */
574 uw_thread_attach (char *args
, int from_tty
)
576 procfs_ops
.to_attach (args
, from_tty
);
577 if (uw_thread_active
)
581 /* Detach from the process attached to by uw_thread_attach(). */
584 uw_thread_detach (char *args
, int from_tty
)
586 deactivate_uw_thread ();
587 base_ops
.to_detach (args
, from_tty
);
590 /* Tell the inferior process to continue running thread PID if >= 0
591 and all threads otherwise. */
594 uw_thread_resume (ptid_t ptid
, int step
, enum target_signal signo
)
596 if (PIDGET (ptid
) > 0)
598 ptid
= thr_to_lwp (ptid
);
599 if (ptid_equal (ptid
, null_ptid
))
600 ptid
= pid_to_ptid (-1);
603 CALL_BASE (base_ops
.to_resume (ptid
, step
, signo
));
606 /* If the trap we just received from lwp PID was due to a breakpoint
607 on the libthread.so debugging stub, update this module's state
611 libthread_stub (ptid_t ptid
)
613 CORE_ADDR sp
, mapp
, mapp_main
;
614 enum thread_change change
;
615 struct thread_map map
;
618 ptid_t tid
= null_ptid
;
619 struct thread_info
*info
;
621 /* Check for stub breakpoint. */
622 if (read_pc_pid (ptid
) - DECR_PC_AFTER_BREAK
!= thr_brk_addr
)
625 /* Retrieve stub args. */
626 sp
= read_register_pid (SP_REGNUM
, ptid
);
627 if (!base_ops
.to_xfer_memory (sp
+ SP_ARG0
, (char *)&mapp
,
628 sizeof (mapp
), 0, NULL
, &base_ops
))
630 if (!base_ops
.to_xfer_memory (sp
+ SP_ARG0
+ sizeof (mapp
), (char *)&change
,
631 sizeof (change
), 0, NULL
, &base_ops
))
634 /* create_inferior() may not have finished yet, so notice the main
635 thread to ensure that it's displayed first by add_thread(). */
636 mapp_main
= find_main ();
638 /* Notice thread creation, deletion, or stability change. */
640 case tc_switch_begin
:
641 if (!mapp
) /* usually means main thread */
645 case tc_thread_create
:
649 if (!read_map (mapp
, &map
))
651 tid
= MKTID (PIDGET (ptid
), map
.thr_tid
);
654 case tc_thread_create
: /* new thread */
657 else if (!read_lwp ((CORE_ADDR
)map
.thr_lwpp
, &lwp
))
661 add_thread_uw (map
.thr_tid
, lwpid
, mapp
, tid
);
664 case tc_thread_exit
: /* thread has exited */
665 printf_unfiltered ("[Exited %s]\n", target_pid_to_str (tid
));
667 if (ptid_equal (tid
, inferior_ptid
))
668 inferior_ptid
= ptid
;
671 case tc_switch_begin
: /* lwp is switching threads */
674 if (!(switchto_thread
= find_thread_pid (tid
)))
676 switchto_thread
->private->stable
= 0;
684 case tc_switch_complete
: /* lwp has switched threads */
685 case tc_cancel_complete
: /* lwp didn't switch threads */
686 if (!switchto_thread
)
689 if (change
== tc_switch_complete
)
691 /* If switchto_thread is the main thread, then (a) the corresponding
692 tc_switch_begin probably received a null map argument and therefore
693 (b) it may have been a spurious switch following a tc_thread_exit.
695 Therefore, explicitly query the thread's lwp before caching it in
696 its thread list entry. */
698 if (!read_map (switchto_thread
->private->mapp
, &map
))
702 if (!read_lwp ((CORE_ADDR
)map
.thr_lwpp
, &lwp
))
704 if ((info
= find_thread_lwp (lwp
.lwp_id
)))
705 info
->private->lwpid
= 0;
706 switchto_thread
->private->lwpid
= lwp
.lwp_id
;
710 switchto_thread
->private->stable
= 1;
711 switchto_thread
= NULL
;
715 case tc_thread_suspend
:
716 case tc_thread_suspend_pending
:
717 case tc_thread_continue
:
719 DBG(("unexpected condition in libthread_stub()"));
723 DBG2(("libthread_stub(%s): %s %s %s", dbgpid (pid
), dbgpid (tid
),
724 dbgchange (change
), tid
? dbgstate (map
.thr_state
) : ""));
727 /* Wait for thread/lwp/process ID if >= 0 or for any thread otherwise. */
730 uw_thread_wait (ptid_t ptid
, struct target_waitstatus
*status
)
732 if (PIDGET (ptid
) > 0)
733 ptid
= thr_to_lwp (ptid
);
734 if (PIDGET (ptid
) <= 0)
735 ptid
= pid_to_ptid (-1);
737 CALL_BASE (ptid
= base_ops
.to_wait (ptid
, status
));
739 if (status
->kind
== TARGET_WAITKIND_STOPPED
&&
740 status
->value
.sig
== TARGET_SIGNAL_TRAP
)
741 libthread_stub (ptid
);
743 return lwp_to_thr (ptid
);
746 /* Tell gdb about the registers in the thread/lwp/process specified by
750 uw_thread_fetch_registers (int regno
)
753 struct thread_info
*info
;
754 struct thread_map map
;
756 TRY_BASE (base_ops
.to_fetch_registers (regno
), &called
);
760 if (!(info
= find_thread_pid (inferior_ptid
)))
762 if (!read_map (info
->private->mapp
, &map
))
765 supply_gregset (&map
.thr_ucontext
.uc_mcontext
.gregs
);
766 supply_fpregset (&map
.thr_ucontext
.uc_mcontext
.fpregs
);
769 /* Store gdb's current view of the register set into the thread/lwp/process
770 specified by inferior_ptid. */
773 uw_thread_store_registers (int regno
)
775 CALL_BASE (base_ops
.to_store_registers (regno
));
778 /* Prepare to modify the registers array. */
781 uw_thread_prepare_to_store (void)
783 CALL_BASE (base_ops
.to_prepare_to_store ());
786 /* Fork an inferior process and start debugging it.
788 This function only gets called with uw_thread_active == 0. */
791 uw_thread_create_inferior (char *exec_file
, char *allargs
, char **env
)
793 if (uw_thread_active
)
794 deactivate_uw_thread ();
796 procfs_ops
.to_create_inferior (exec_file
, allargs
, env
);
797 if (uw_thread_active
)
804 /* Kill and forget about the inferior process. */
807 uw_thread_kill (void)
812 /* Clean up after the inferior exits. */
815 uw_thread_mourn_inferior (void)
817 deactivate_uw_thread ();
818 base_ops
.to_mourn_inferior ();
821 /* Return whether this module can attach to and run processes.
823 This function only gets called with uw_thread_active == 0. */
826 uw_thread_can_run (void)
828 return procfs_suppress_run
;
831 /* Return whether thread PID is still valid. */
834 uw_thread_alive (ptid_t ptid
)
837 return base_ops
.to_thread_alive (ptid
);
839 /* If it's in the thread list, it's valid, because otherwise
840 libthread_stub() would have deleted it. */
841 return in_thread_list (ptid
);
844 /* Add to the thread list any threads and lwps it doesn't already contain. */
847 uw_thread_find_new_threads (void)
849 CALL_BASE (if (base_ops
.to_find_new_threads
)
850 base_ops
.to_find_new_threads ());
854 /* Return a string for pretty-printing PID in "info threads" output.
855 This may be called by either procfs.c or by generic gdb. */
858 uw_thread_pid_to_str (ptid_t ptid
)
860 #define FMT "Thread %ld"
861 static char buf
[sizeof (FMT
) + 3 * sizeof (long)];
864 /* core_ops says "process foo", so call procfs_ops explicitly. */
865 return procfs_ops
.to_pid_to_str (ptid
);
867 sprintf (buf
, FMT
, TIDGET (ptid
));
872 /* Return a string displaying INFO state information in "info threads"
876 uw_extra_thread_info (struct thread_info
*info
)
879 struct thread_map map
;
884 if (!ISTID (info
->ptid
))
887 if (!info
->private->stable
)
890 if (!read_map (info
->private->mapp
, &map
))
893 if (!map
.thr_lwpp
|| !read_lwp ((CORE_ADDR
)map
.thr_lwpp
, &lwp
))
898 switch (map
.thr_state
) {
899 case TS_ONPROC
: name
= "running"; break;
900 case TS_SLEEP
: name
= "sleeping"; break;
901 case TS_RUNNABLE
: name
= "runnable"; break;
902 case TS_ZOMBIE
: name
= "zombie"; break;
903 case TS_SUSPENDED
: name
= "suspended"; break;
905 case TS_FORK
: name
= "forking"; break;
907 default: name
= "confused"; break;
913 sprintf (buf
, "%s, LWP %d", name
, lwpid
);
917 /* Check whether libthread.so has just been loaded, and if so, try to
918 initialize user-space thread debugging support.
920 libthread.so loading happens while (a) an inferior process is being
921 started by procfs and (b) a core image is being loaded.
923 This function often gets called with uw_thread_active == 0. */
926 libthread_init (void)
928 struct minimal_symbol
*ms
;
929 struct thread_debug debug
;
931 struct breakpoint
*b
;
934 /* Don't initialize twice. */
935 if (uw_thread_active
)
938 /* Check whether libthread.so has been loaded. */
939 if (!(ms
= lookup_minimal_symbol ("_thr_debug", NULL
, NULL
)))
942 /* Cache _thr_debug's address. */
943 if (!(thr_debug_addr
= SYMBOL_VALUE_ADDRESS (ms
)))
946 /* Initialize base_ops.to_xfer_memory(). */
947 base_ops
= current_target
;
949 /* Load _thr_debug's current contents. */
950 if (!read_thr_debug (&debug
))
953 /* User code (e.g. my test programs) may dereference _thr_debug,
954 making it availble to GDB before shared libs are loaded. */
958 /* libthread.so has been loaded, and the current_target should now
959 reflect core_ops or procfs_ops. */
960 push_target (&uw_thread_ops
); /* must precede notice_threads() */
961 uw_thread_active
= 1;
963 if (!target_has_execution
)
965 /* Locate threads in core file. */
970 /* Set a breakpoint on the stub function provided by libthread.so. */
971 thr_brk_addr
= (CORE_ADDR
)debug
.thr_brk
;
972 if (!(b
= create_thread_event_breakpoint (thr_brk_addr
)))
975 /* Activate the stub function. */
976 onp
= (CORE_ADDR
)&((struct thread_debug
*)thr_debug_addr
)->thr_debug_on
;
977 if (!base_ops
.to_xfer_memory ((CORE_ADDR
)onp
, (char *)&one
,
978 sizeof (one
), 1, NULL
, &base_ops
))
980 delete_breakpoint (b
);
984 /* Prepare for finding the main thread, which doesn't yet exist. */
991 warning ("uw-thread: unable to initialize user-mode thread debugging\n");
992 deactivate_uw_thread ();
995 /* target_new_objfile_hook callback.
997 If OBJFILE is non-null, check whether libthread.so was just loaded,
998 and if so, prepare for user-mode thread debugging.
1000 If OBJFILE is null, libthread.so has gone away, so stop debugging
1003 This function often gets called with uw_thread_active == 0. */
1006 uw_thread_new_objfile (struct objfile
*objfile
)
1011 else if (uw_thread_active
)
1012 deactivate_uw_thread ();
1014 if (target_new_objfile_chain
)
1015 target_new_objfile_chain (objfile
);
1018 /* Initialize uw_thread_ops. */
1021 init_uw_thread_ops (void)
1023 uw_thread_ops
.to_shortname
= "unixware-threads";
1024 uw_thread_ops
.to_longname
= "UnixWare threads and pthread.";
1025 uw_thread_ops
.to_doc
= "UnixWare threads and pthread support.";
1026 uw_thread_ops
.to_attach
= uw_thread_attach
;
1027 uw_thread_ops
.to_detach
= uw_thread_detach
;
1028 uw_thread_ops
.to_resume
= uw_thread_resume
;
1029 uw_thread_ops
.to_wait
= uw_thread_wait
;
1030 uw_thread_ops
.to_fetch_registers
= uw_thread_fetch_registers
;
1031 uw_thread_ops
.to_store_registers
= uw_thread_store_registers
;
1032 uw_thread_ops
.to_prepare_to_store
= uw_thread_prepare_to_store
;
1033 uw_thread_ops
.to_create_inferior
= uw_thread_create_inferior
;
1034 uw_thread_ops
.to_kill
= uw_thread_kill
;
1035 uw_thread_ops
.to_mourn_inferior
= uw_thread_mourn_inferior
;
1036 uw_thread_ops
.to_can_run
= uw_thread_can_run
;
1037 uw_thread_ops
.to_thread_alive
= uw_thread_alive
;
1038 uw_thread_ops
.to_find_new_threads
= uw_thread_find_new_threads
;
1039 uw_thread_ops
.to_pid_to_str
= uw_thread_pid_to_str
;
1040 uw_thread_ops
.to_extra_thread_info
= uw_extra_thread_info
;
1041 uw_thread_ops
.to_stratum
= thread_stratum
;
1042 uw_thread_ops
.to_magic
= OPS_MAGIC
;
1045 /* Module startup initialization function, automagically called by
1049 _initialize_uw_thread (void)
1051 init_uw_thread_ops ();
1052 add_target (&uw_thread_ops
);
1054 procfs_suppress_run
= 1;
1056 /* Notice when libthread.so gets loaded. */
1057 target_new_objfile_chain
= target_new_objfile_hook
;
1058 target_new_objfile_hook
= uw_thread_new_objfile
;