Commit | Line | Data |
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0d62e5e8 | 1 | /* Thread management interface, for the remote server for GDB. |
32d0add0 | 2 | Copyright (C) 2002-2015 Free Software Foundation, Inc. |
0d62e5e8 DJ |
3 | |
4 | Contributed by MontaVista Software. | |
5 | ||
6 | This file is part of GDB. | |
7 | ||
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 | |
a9762ec7 | 10 | the Free Software Foundation; either version 3 of the License, or |
0d62e5e8 DJ |
11 | (at your option) any later version. |
12 | ||
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. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
0d62e5e8 DJ |
20 | |
21 | #include "server.h" | |
22 | ||
23 | #include "linux-low.h" | |
24 | ||
25 | extern int debug_threads; | |
26 | ||
24a09b5f DJ |
27 | static int thread_db_use_events; |
28 | ||
0050a760 | 29 | #include "gdb_proc_service.h" |
125f8a3d | 30 | #include "nat/gdb_thread_db.h" |
e6712ff1 | 31 | #include "gdb_vecs.h" |
2db9a427 | 32 | #include "nat/linux-procfs.h" |
0d62e5e8 | 33 | |
96f15937 | 34 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 | 35 | #include <dlfcn.h> |
96f15937 | 36 | #endif |
cdbfd419 PP |
37 | #include <limits.h> |
38 | #include <ctype.h> | |
39 | ||
40 | struct thread_db | |
41 | { | |
42 | /* Structure that identifies the child process for the | |
43 | <proc_service.h> interface. */ | |
44 | struct ps_prochandle proc_handle; | |
45 | ||
46 | /* Connection to the libthread_db library. */ | |
47 | td_thragent_t *thread_agent; | |
48 | ||
9836d6ea PA |
49 | /* If this flag has been set, we've already asked GDB for all |
50 | symbols we might need; assume symbol cache misses are | |
51 | failures. */ | |
52 | int all_symbols_looked_up; | |
53 | ||
96f15937 | 54 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 PP |
55 | /* Handle of the libthread_db from dlopen. */ |
56 | void *handle; | |
96f15937 | 57 | #endif |
cdbfd419 | 58 | |
f9e39928 PA |
59 | /* Thread creation event breakpoint. The code at this location in |
60 | the child process will be called by the pthread library whenever | |
61 | a new thread is created. By setting a special breakpoint at this | |
62 | location, GDB can detect when a new thread is created. We obtain | |
63 | this location via the td_ta_event_addr call. Note that if the | |
64 | running kernel supports tracing clones, then we don't need to use | |
65 | (and in fact don't use) this magic thread event breakpoint to | |
66 | learn about threads. */ | |
67 | struct breakpoint *td_create_bp; | |
68 | ||
cdbfd419 PP |
69 | /* Addresses of libthread_db functions. */ |
70 | td_err_e (*td_ta_new_p) (struct ps_prochandle * ps, td_thragent_t **ta); | |
71 | td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta, | |
72 | td_event_msg_t *msg); | |
73 | td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta, | |
74 | td_thr_events_t *event); | |
75 | td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta, | |
76 | td_event_e event, td_notify_t *ptr); | |
77 | td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta, lwpid_t lwpid, | |
78 | td_thrhandle_t *th); | |
79 | td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th, | |
80 | td_thrinfo_t *infop); | |
81 | td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th, int event); | |
82 | td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta, | |
83 | td_thr_iter_f *callback, void *cbdata_p, | |
84 | td_thr_state_e state, int ti_pri, | |
85 | sigset_t *ti_sigmask_p, | |
86 | unsigned int ti_user_flags); | |
87 | td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th, | |
00f515da DE |
88 | psaddr_t map_address, |
89 | size_t offset, psaddr_t *address); | |
5876f503 JK |
90 | td_err_e (*td_thr_tlsbase_p) (const td_thrhandle_t *th, |
91 | unsigned long int modid, | |
92 | psaddr_t *base); | |
cdbfd419 PP |
93 | const char ** (*td_symbol_list_p) (void); |
94 | }; | |
95 | ||
96 | static char *libthread_db_search_path; | |
186947f7 | 97 | |
95954743 | 98 | static int find_one_thread (ptid_t); |
0d62e5e8 DJ |
99 | static int find_new_threads_callback (const td_thrhandle_t *th_p, void *data); |
100 | ||
54363045 | 101 | static const char * |
0d62e5e8 DJ |
102 | thread_db_err_str (td_err_e err) |
103 | { | |
104 | static char buf[64]; | |
105 | ||
106 | switch (err) | |
107 | { | |
108 | case TD_OK: | |
109 | return "generic 'call succeeded'"; | |
110 | case TD_ERR: | |
111 | return "generic error"; | |
112 | case TD_NOTHR: | |
113 | return "no thread to satisfy query"; | |
114 | case TD_NOSV: | |
115 | return "no sync handle to satisfy query"; | |
116 | case TD_NOLWP: | |
117 | return "no LWP to satisfy query"; | |
118 | case TD_BADPH: | |
119 | return "invalid process handle"; | |
120 | case TD_BADTH: | |
121 | return "invalid thread handle"; | |
122 | case TD_BADSH: | |
123 | return "invalid synchronization handle"; | |
124 | case TD_BADTA: | |
125 | return "invalid thread agent"; | |
126 | case TD_BADKEY: | |
127 | return "invalid key"; | |
128 | case TD_NOMSG: | |
129 | return "no event message for getmsg"; | |
130 | case TD_NOFPREGS: | |
131 | return "FPU register set not available"; | |
132 | case TD_NOLIBTHREAD: | |
133 | return "application not linked with libthread"; | |
134 | case TD_NOEVENT: | |
135 | return "requested event is not supported"; | |
136 | case TD_NOCAPAB: | |
137 | return "capability not available"; | |
138 | case TD_DBERR: | |
139 | return "debugger service failed"; | |
140 | case TD_NOAPLIC: | |
141 | return "operation not applicable to"; | |
142 | case TD_NOTSD: | |
143 | return "no thread-specific data for this thread"; | |
144 | case TD_MALLOC: | |
145 | return "malloc failed"; | |
146 | case TD_PARTIALREG: | |
147 | return "only part of register set was written/read"; | |
148 | case TD_NOXREGS: | |
149 | return "X register set not available for this thread"; | |
3db0444b DJ |
150 | #ifdef HAVE_TD_VERSION |
151 | case TD_VERSION: | |
152 | return "version mismatch between libthread_db and libpthread"; | |
153 | #endif | |
0d62e5e8 | 154 | default: |
6cebaf6e | 155 | xsnprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
0d62e5e8 DJ |
156 | return buf; |
157 | } | |
158 | } | |
159 | ||
160 | #if 0 | |
161 | static char * | |
162 | thread_db_state_str (td_thr_state_e state) | |
163 | { | |
164 | static char buf[64]; | |
165 | ||
166 | switch (state) | |
167 | { | |
168 | case TD_THR_STOPPED: | |
169 | return "stopped by debugger"; | |
170 | case TD_THR_RUN: | |
171 | return "runnable"; | |
172 | case TD_THR_ACTIVE: | |
173 | return "active"; | |
174 | case TD_THR_ZOMBIE: | |
175 | return "zombie"; | |
176 | case TD_THR_SLEEP: | |
177 | return "sleeping"; | |
178 | case TD_THR_STOPPED_ASLEEP: | |
179 | return "stopped by debugger AND blocked"; | |
180 | default: | |
6cebaf6e | 181 | xsnprintf (buf, sizeof (buf), "unknown thread_db state %d", state); |
0d62e5e8 DJ |
182 | return buf; |
183 | } | |
184 | } | |
185 | #endif | |
186 | ||
b65d95c5 | 187 | static int |
0d62e5e8 DJ |
188 | thread_db_create_event (CORE_ADDR where) |
189 | { | |
190 | td_event_msg_t msg; | |
191 | td_err_e err; | |
54a0b537 | 192 | struct lwp_info *lwp; |
fe978cb0 | 193 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
cdbfd419 | 194 | |
38e08fca | 195 | gdb_assert (thread_db->td_ta_event_getmsg_p != NULL); |
0d62e5e8 DJ |
196 | |
197 | if (debug_threads) | |
87ce2a04 | 198 | debug_printf ("Thread creation event.\n"); |
0d62e5e8 | 199 | |
0d62e5e8 DJ |
200 | /* FIXME: This assumes we don't get another event. |
201 | In the LinuxThreads implementation, this is safe, | |
202 | because all events come from the manager thread | |
203 | (except for its own creation, of course). */ | |
cdbfd419 | 204 | err = thread_db->td_ta_event_getmsg_p (thread_db->thread_agent, &msg); |
0d62e5e8 DJ |
205 | if (err != TD_OK) |
206 | fprintf (stderr, "thread getmsg err: %s\n", | |
207 | thread_db_err_str (err)); | |
208 | ||
4105de34 DJ |
209 | /* If we do not know about the main thread yet, this would be a good time to |
210 | find it. We need to do this to pick up the main thread before any newly | |
211 | created threads. */ | |
0bfdf32f | 212 | lwp = get_thread_lwp (current_thread); |
54a0b537 | 213 | if (lwp->thread_known == 0) |
0bfdf32f | 214 | find_one_thread (current_thread->entry.id); |
4105de34 | 215 | |
0d62e5e8 DJ |
216 | /* msg.event == TD_EVENT_CREATE */ |
217 | ||
218 | find_new_threads_callback (msg.th_p, NULL); | |
b65d95c5 DJ |
219 | |
220 | return 0; | |
0d62e5e8 DJ |
221 | } |
222 | ||
0d62e5e8 | 223 | static int |
f9e39928 | 224 | thread_db_enable_reporting (void) |
0d62e5e8 DJ |
225 | { |
226 | td_thr_events_t events; | |
227 | td_notify_t notify; | |
228 | td_err_e err; | |
fe978cb0 | 229 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
cdbfd419 PP |
230 | |
231 | if (thread_db->td_ta_set_event_p == NULL | |
232 | || thread_db->td_ta_event_addr_p == NULL | |
233 | || thread_db->td_ta_event_getmsg_p == NULL) | |
234 | /* This libthread_db is missing required support. */ | |
235 | return 0; | |
0d62e5e8 DJ |
236 | |
237 | /* Set the process wide mask saying which events we're interested in. */ | |
238 | td_event_emptyset (&events); | |
239 | td_event_addset (&events, TD_CREATE); | |
240 | ||
cdbfd419 | 241 | err = thread_db->td_ta_set_event_p (thread_db->thread_agent, &events); |
0d62e5e8 DJ |
242 | if (err != TD_OK) |
243 | { | |
244 | warning ("Unable to set global thread event mask: %s", | |
1b3f6016 | 245 | thread_db_err_str (err)); |
0d62e5e8 DJ |
246 | return 0; |
247 | } | |
248 | ||
249 | /* Get address for thread creation breakpoint. */ | |
cdbfd419 PP |
250 | err = thread_db->td_ta_event_addr_p (thread_db->thread_agent, TD_CREATE, |
251 | ¬ify); | |
0d62e5e8 DJ |
252 | if (err != TD_OK) |
253 | { | |
254 | warning ("Unable to get location for thread creation breakpoint: %s", | |
255 | thread_db_err_str (err)); | |
256 | return 0; | |
257 | } | |
f9e39928 PA |
258 | thread_db->td_create_bp |
259 | = set_breakpoint_at ((CORE_ADDR) (unsigned long) notify.u.bptaddr, | |
260 | thread_db_create_event); | |
0d62e5e8 | 261 | |
0d62e5e8 DJ |
262 | return 1; |
263 | } | |
264 | ||
ae13219e | 265 | static int |
95954743 | 266 | find_one_thread (ptid_t ptid) |
0d62e5e8 | 267 | { |
ae13219e DJ |
268 | td_thrhandle_t th; |
269 | td_thrinfo_t ti; | |
0d62e5e8 DJ |
270 | td_err_e err; |
271 | struct thread_info *inferior; | |
54a0b537 | 272 | struct lwp_info *lwp; |
fe978cb0 | 273 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
95954743 | 274 | int lwpid = ptid_get_lwp (ptid); |
0d62e5e8 | 275 | |
95954743 | 276 | inferior = (struct thread_info *) find_inferior_id (&all_threads, ptid); |
54a0b537 PA |
277 | lwp = get_thread_lwp (inferior); |
278 | if (lwp->thread_known) | |
ae13219e DJ |
279 | return 1; |
280 | ||
24a09b5f | 281 | /* Get information about this thread. */ |
cdbfd419 | 282 | err = thread_db->td_ta_map_lwp2thr_p (thread_db->thread_agent, lwpid, &th); |
ae13219e | 283 | if (err != TD_OK) |
24a09b5f DJ |
284 | error ("Cannot get thread handle for LWP %d: %s", |
285 | lwpid, thread_db_err_str (err)); | |
ae13219e | 286 | |
cdbfd419 | 287 | err = thread_db->td_thr_get_info_p (&th, &ti); |
ae13219e | 288 | if (err != TD_OK) |
24a09b5f DJ |
289 | error ("Cannot get thread info for LWP %d: %s", |
290 | lwpid, thread_db_err_str (err)); | |
ae13219e DJ |
291 | |
292 | if (debug_threads) | |
87ce2a04 DE |
293 | debug_printf ("Found thread %ld (LWP %d)\n", |
294 | ti.ti_tid, ti.ti_lid); | |
ae13219e | 295 | |
95954743 | 296 | if (lwpid != ti.ti_lid) |
24a09b5f DJ |
297 | { |
298 | warning ("PID mismatch! Expected %ld, got %ld", | |
95954743 | 299 | (long) lwpid, (long) ti.ti_lid); |
24a09b5f DJ |
300 | return 0; |
301 | } | |
ae13219e | 302 | |
24a09b5f | 303 | if (thread_db_use_events) |
0d62e5e8 | 304 | { |
cdbfd419 | 305 | err = thread_db->td_thr_event_enable_p (&th, 1); |
ae13219e DJ |
306 | if (err != TD_OK) |
307 | error ("Cannot enable thread event reporting for %d: %s", | |
308 | ti.ti_lid, thread_db_err_str (err)); | |
0d62e5e8 | 309 | } |
ae13219e | 310 | |
24a09b5f DJ |
311 | /* If the new thread ID is zero, a final thread ID will be available |
312 | later. Do not enable thread debugging yet. */ | |
313 | if (ti.ti_tid == 0) | |
314 | return 0; | |
ae13219e | 315 | |
54a0b537 PA |
316 | lwp->thread_known = 1; |
317 | lwp->th = th; | |
ae13219e | 318 | |
ae13219e DJ |
319 | return 1; |
320 | } | |
321 | ||
5f7d1694 PP |
322 | /* Attach a thread. Return true on success. */ |
323 | ||
324 | static int | |
325 | attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p) | |
ae13219e | 326 | { |
7ae1a6a6 PA |
327 | struct process_info *proc = current_process (); |
328 | int pid = pid_of (proc); | |
329 | ptid_t ptid = ptid_build (pid, ti_p->ti_lid, 0); | |
54a0b537 | 330 | struct lwp_info *lwp; |
7ae1a6a6 | 331 | int err; |
ae13219e | 332 | |
0d62e5e8 | 333 | if (debug_threads) |
87ce2a04 DE |
334 | debug_printf ("Attaching to thread %ld (LWP %d)\n", |
335 | ti_p->ti_tid, ti_p->ti_lid); | |
7ae1a6a6 PA |
336 | err = linux_attach_lwp (ptid); |
337 | if (err != 0) | |
0d62e5e8 | 338 | { |
7ae1a6a6 PA |
339 | warning ("Could not attach to thread %ld (LWP %d): %s\n", |
340 | ti_p->ti_tid, ti_p->ti_lid, | |
8784d563 | 341 | linux_ptrace_attach_fail_reason_string (ptid, err)); |
5f7d1694 | 342 | return 0; |
0d62e5e8 DJ |
343 | } |
344 | ||
7ae1a6a6 PA |
345 | lwp = find_lwp_pid (ptid); |
346 | gdb_assert (lwp != NULL); | |
54a0b537 PA |
347 | lwp->thread_known = 1; |
348 | lwp->th = *th_p; | |
24a09b5f DJ |
349 | |
350 | if (thread_db_use_events) | |
351 | { | |
5f7d1694 | 352 | td_err_e err; |
fe978cb0 | 353 | struct thread_db *thread_db = proc->priv->thread_db; |
5f7d1694 | 354 | |
cdbfd419 | 355 | err = thread_db->td_thr_event_enable_p (th_p, 1); |
24a09b5f DJ |
356 | if (err != TD_OK) |
357 | error ("Cannot enable thread event reporting for %d: %s", | |
358 | ti_p->ti_lid, thread_db_err_str (err)); | |
359 | } | |
5f7d1694 PP |
360 | |
361 | return 1; | |
362 | } | |
363 | ||
364 | /* Attach thread if we haven't seen it yet. | |
365 | Increment *COUNTER if we have attached a new thread. | |
366 | Return false on failure. */ | |
367 | ||
368 | static int | |
369 | maybe_attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p, | |
370 | int *counter) | |
371 | { | |
372 | struct lwp_info *lwp; | |
373 | ||
374 | lwp = find_lwp_pid (pid_to_ptid (ti_p->ti_lid)); | |
375 | if (lwp != NULL) | |
376 | return 1; | |
377 | ||
378 | if (!attach_thread (th_p, ti_p)) | |
379 | return 0; | |
380 | ||
381 | if (counter != NULL) | |
382 | *counter += 1; | |
383 | ||
384 | return 1; | |
0d62e5e8 DJ |
385 | } |
386 | ||
387 | static int | |
388 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) | |
389 | { | |
390 | td_thrinfo_t ti; | |
391 | td_err_e err; | |
fe978cb0 | 392 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
0d62e5e8 | 393 | |
cdbfd419 | 394 | err = thread_db->td_thr_get_info_p (th_p, &ti); |
0d62e5e8 DJ |
395 | if (err != TD_OK) |
396 | error ("Cannot get thread info: %s", thread_db_err_str (err)); | |
397 | ||
a33e3959 PA |
398 | if (ti.ti_lid == -1) |
399 | { | |
400 | /* A thread with kernel thread ID -1 is either a thread that | |
401 | exited and was joined, or a thread that is being created but | |
402 | hasn't started yet, and that is reusing the tcb/stack of a | |
403 | thread that previously exited and was joined. (glibc marks | |
404 | terminated and joined threads with kernel thread ID -1. See | |
405 | glibc PR17707. */ | |
d6c146e9 PA |
406 | if (debug_threads) |
407 | debug_printf ("thread_db: skipping exited and " | |
408 | "joined thread (0x%lx)\n", ti.ti_tid); | |
a33e3959 PA |
409 | return 0; |
410 | } | |
411 | ||
0d62e5e8 DJ |
412 | /* Check for zombies. */ |
413 | if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE) | |
414 | return 0; | |
415 | ||
5f7d1694 PP |
416 | if (!maybe_attach_thread (th_p, &ti, (int *) data)) |
417 | { | |
418 | /* Terminate iteration early: we might be looking at stale data in | |
419 | the inferior. The thread_db_find_new_threads will retry. */ | |
420 | return 1; | |
421 | } | |
0d62e5e8 DJ |
422 | |
423 | return 0; | |
424 | } | |
425 | ||
426 | static void | |
427 | thread_db_find_new_threads (void) | |
428 | { | |
429 | td_err_e err; | |
fbd5db48 | 430 | ptid_t ptid = current_ptid; |
fe978cb0 | 431 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
5f7d1694 | 432 | int loop, iteration; |
0d62e5e8 | 433 | |
ae13219e DJ |
434 | /* This function is only called when we first initialize thread_db. |
435 | First locate the initial thread. If it is not ready for | |
436 | debugging yet, then stop. */ | |
95954743 | 437 | if (find_one_thread (ptid) == 0) |
ae13219e DJ |
438 | return; |
439 | ||
5f7d1694 PP |
440 | /* Require 4 successive iterations which do not find any new threads. |
441 | The 4 is a heuristic: there is an inherent race here, and I have | |
442 | seen that 2 iterations in a row are not always sufficient to | |
443 | "capture" all threads. */ | |
444 | for (loop = 0, iteration = 0; loop < 4; ++loop, ++iteration) | |
445 | { | |
446 | int new_thread_count = 0; | |
447 | ||
448 | /* Iterate over all user-space threads to discover new threads. */ | |
449 | err = thread_db->td_ta_thr_iter_p (thread_db->thread_agent, | |
450 | find_new_threads_callback, | |
451 | &new_thread_count, | |
493e2a69 MS |
452 | TD_THR_ANY_STATE, |
453 | TD_THR_LOWEST_PRIORITY, | |
5f7d1694 PP |
454 | TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS); |
455 | if (debug_threads) | |
87ce2a04 DE |
456 | debug_printf ("Found %d threads in iteration %d.\n", |
457 | new_thread_count, iteration); | |
5f7d1694 PP |
458 | |
459 | if (new_thread_count != 0) | |
460 | { | |
461 | /* Found new threads. Restart iteration from beginning. */ | |
462 | loop = -1; | |
463 | } | |
464 | } | |
0d62e5e8 DJ |
465 | if (err != TD_OK) |
466 | error ("Cannot find new threads: %s", thread_db_err_str (err)); | |
467 | } | |
468 | ||
fd500816 DJ |
469 | /* Cache all future symbols that thread_db might request. We can not |
470 | request symbols at arbitrary states in the remote protocol, only | |
471 | when the client tells us that new symbols are available. So when | |
472 | we load the thread library, make sure to check the entire list. */ | |
473 | ||
474 | static void | |
475 | thread_db_look_up_symbols (void) | |
476 | { | |
fe978cb0 | 477 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
cdbfd419 | 478 | const char **sym_list; |
fd500816 DJ |
479 | CORE_ADDR unused; |
480 | ||
cdbfd419 | 481 | for (sym_list = thread_db->td_symbol_list_p (); *sym_list; sym_list++) |
9836d6ea PA |
482 | look_up_one_symbol (*sym_list, &unused, 1); |
483 | ||
484 | /* We're not interested in any other libraries loaded after this | |
485 | point, only in symbols in libpthread.so. */ | |
486 | thread_db->all_symbols_looked_up = 1; | |
487 | } | |
488 | ||
489 | int | |
490 | thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp) | |
491 | { | |
fe978cb0 | 492 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
9836d6ea PA |
493 | int may_ask_gdb = !thread_db->all_symbols_looked_up; |
494 | ||
495 | /* If we've passed the call to thread_db_look_up_symbols, then | |
496 | anything not in the cache must not exist; we're not interested | |
497 | in any libraries loaded after that point, only in symbols in | |
498 | libpthread.so. It might not be an appropriate time to look | |
499 | up a symbol, e.g. while we're trying to fetch registers. */ | |
500 | return look_up_one_symbol (name, addrp, may_ask_gdb); | |
fd500816 DJ |
501 | } |
502 | ||
dae5f5cf DJ |
503 | int |
504 | thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset, | |
505 | CORE_ADDR load_module, CORE_ADDR *address) | |
506 | { | |
dae5f5cf DJ |
507 | psaddr_t addr; |
508 | td_err_e err; | |
54a0b537 | 509 | struct lwp_info *lwp; |
0bfdf32f | 510 | struct thread_info *saved_thread; |
cdbfd419 PP |
511 | struct process_info *proc; |
512 | struct thread_db *thread_db; | |
513 | ||
514 | proc = get_thread_process (thread); | |
fe978cb0 | 515 | thread_db = proc->priv->thread_db; |
dae5f5cf | 516 | |
7fe519cb | 517 | /* If the thread layer is not (yet) initialized, fail. */ |
8a4ac37e | 518 | if (thread_db == NULL || !thread_db->all_symbols_looked_up) |
7fe519cb UW |
519 | return TD_ERR; |
520 | ||
5876f503 JK |
521 | /* If td_thr_tls_get_addr is missing rather do not expect td_thr_tlsbase |
522 | could work. */ | |
523 | if (thread_db->td_thr_tls_get_addr_p == NULL | |
524 | || (load_module == 0 && thread_db->td_thr_tlsbase_p == NULL)) | |
cdbfd419 PP |
525 | return -1; |
526 | ||
54a0b537 PA |
527 | lwp = get_thread_lwp (thread); |
528 | if (!lwp->thread_known) | |
80894984 | 529 | find_one_thread (thread->entry.id); |
54a0b537 | 530 | if (!lwp->thread_known) |
dae5f5cf DJ |
531 | return TD_NOTHR; |
532 | ||
0bfdf32f GB |
533 | saved_thread = current_thread; |
534 | current_thread = thread; | |
5876f503 JK |
535 | |
536 | if (load_module != 0) | |
537 | { | |
538 | /* Note the cast through uintptr_t: this interface only works if | |
539 | a target address fits in a psaddr_t, which is a host pointer. | |
540 | So a 32-bit debugger can not access 64-bit TLS through this. */ | |
541 | err = thread_db->td_thr_tls_get_addr_p (&lwp->th, | |
542 | (psaddr_t) (uintptr_t) load_module, | |
543 | offset, &addr); | |
544 | } | |
545 | else | |
546 | { | |
547 | /* This code path handles the case of -static -pthread executables: | |
548 | https://sourceware.org/ml/libc-help/2014-03/msg00024.html | |
549 | For older GNU libc r_debug.r_map is NULL. For GNU libc after | |
550 | PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL. | |
551 | The constant number 1 depends on GNU __libc_setup_tls | |
552 | initialization of l_tls_modid to 1. */ | |
553 | err = thread_db->td_thr_tlsbase_p (&lwp->th, 1, &addr); | |
554 | addr = (char *) addr + offset; | |
555 | } | |
556 | ||
0bfdf32f | 557 | current_thread = saved_thread; |
dae5f5cf DJ |
558 | if (err == TD_OK) |
559 | { | |
186947f7 | 560 | *address = (CORE_ADDR) (uintptr_t) addr; |
dae5f5cf DJ |
561 | return 0; |
562 | } | |
563 | else | |
564 | return err; | |
cdbfd419 PP |
565 | } |
566 | ||
96f15937 PP |
567 | #ifdef USE_LIBTHREAD_DB_DIRECTLY |
568 | ||
569 | static int | |
570 | thread_db_load_search (void) | |
571 | { | |
572 | td_err_e err; | |
9836d6ea | 573 | struct thread_db *tdb; |
96f15937 PP |
574 | struct process_info *proc = current_process (); |
575 | ||
fe978cb0 | 576 | gdb_assert (proc->priv->thread_db == NULL); |
96f15937 | 577 | |
9836d6ea | 578 | tdb = xcalloc (1, sizeof (*tdb)); |
fe978cb0 | 579 | proc->priv->thread_db = tdb; |
f9e39928 | 580 | |
9836d6ea | 581 | tdb->td_ta_new_p = &td_ta_new; |
96f15937 PP |
582 | |
583 | /* Attempt to open a connection to the thread library. */ | |
9836d6ea | 584 | err = tdb->td_ta_new_p (&tdb->proc_handle, &tdb->thread_agent); |
96f15937 PP |
585 | if (err != TD_OK) |
586 | { | |
587 | if (debug_threads) | |
87ce2a04 | 588 | debug_printf ("td_ta_new(): %s\n", thread_db_err_str (err)); |
9836d6ea | 589 | free (tdb); |
fe978cb0 | 590 | proc->priv->thread_db = NULL; |
96f15937 PP |
591 | return 0; |
592 | } | |
593 | ||
9836d6ea PA |
594 | tdb->td_ta_map_lwp2thr_p = &td_ta_map_lwp2thr; |
595 | tdb->td_thr_get_info_p = &td_thr_get_info; | |
596 | tdb->td_ta_thr_iter_p = &td_ta_thr_iter; | |
597 | tdb->td_symbol_list_p = &td_symbol_list; | |
96f15937 PP |
598 | |
599 | /* This is required only when thread_db_use_events is on. */ | |
9836d6ea | 600 | tdb->td_thr_event_enable_p = &td_thr_event_enable; |
96f15937 PP |
601 | |
602 | /* These are not essential. */ | |
9836d6ea PA |
603 | tdb->td_ta_event_addr_p = &td_ta_event_addr; |
604 | tdb->td_ta_set_event_p = &td_ta_set_event; | |
605 | tdb->td_ta_event_getmsg_p = &td_ta_event_getmsg; | |
606 | tdb->td_thr_tls_get_addr_p = &td_thr_tls_get_addr; | |
5876f503 | 607 | tdb->td_thr_tlsbase_p = &td_thr_tlsbase; |
96f15937 PP |
608 | |
609 | return 1; | |
610 | } | |
611 | ||
612 | #else | |
613 | ||
cdbfd419 PP |
614 | static int |
615 | try_thread_db_load_1 (void *handle) | |
616 | { | |
617 | td_err_e err; | |
9836d6ea | 618 | struct thread_db *tdb; |
cdbfd419 PP |
619 | struct process_info *proc = current_process (); |
620 | ||
fe978cb0 | 621 | gdb_assert (proc->priv->thread_db == NULL); |
cdbfd419 | 622 | |
9836d6ea | 623 | tdb = xcalloc (1, sizeof (*tdb)); |
fe978cb0 | 624 | proc->priv->thread_db = tdb; |
f9e39928 | 625 | |
9836d6ea | 626 | tdb->handle = handle; |
cdbfd419 PP |
627 | |
628 | /* Initialize pointers to the dynamic library functions we will use. | |
629 | Essential functions first. */ | |
630 | ||
631 | #define CHK(required, a) \ | |
632 | do \ | |
633 | { \ | |
634 | if ((a) == NULL) \ | |
635 | { \ | |
636 | if (debug_threads) \ | |
87ce2a04 | 637 | debug_printf ("dlsym: %s\n", dlerror ()); \ |
cdbfd419 | 638 | if (required) \ |
9836d6ea PA |
639 | { \ |
640 | free (tdb); \ | |
fe978cb0 | 641 | proc->priv->thread_db = NULL; \ |
9836d6ea PA |
642 | return 0; \ |
643 | } \ | |
cdbfd419 PP |
644 | } \ |
645 | } \ | |
646 | while (0) | |
647 | ||
9836d6ea | 648 | CHK (1, tdb->td_ta_new_p = dlsym (handle, "td_ta_new")); |
cdbfd419 PP |
649 | |
650 | /* Attempt to open a connection to the thread library. */ | |
9836d6ea | 651 | err = tdb->td_ta_new_p (&tdb->proc_handle, &tdb->thread_agent); |
cdbfd419 PP |
652 | if (err != TD_OK) |
653 | { | |
654 | if (debug_threads) | |
87ce2a04 | 655 | debug_printf ("td_ta_new(): %s\n", thread_db_err_str (err)); |
9836d6ea | 656 | free (tdb); |
fe978cb0 | 657 | proc->priv->thread_db = NULL; |
cdbfd419 PP |
658 | return 0; |
659 | } | |
660 | ||
9836d6ea PA |
661 | CHK (1, tdb->td_ta_map_lwp2thr_p = dlsym (handle, "td_ta_map_lwp2thr")); |
662 | CHK (1, tdb->td_thr_get_info_p = dlsym (handle, "td_thr_get_info")); | |
663 | CHK (1, tdb->td_ta_thr_iter_p = dlsym (handle, "td_ta_thr_iter")); | |
664 | CHK (1, tdb->td_symbol_list_p = dlsym (handle, "td_symbol_list")); | |
cdbfd419 PP |
665 | |
666 | /* This is required only when thread_db_use_events is on. */ | |
667 | CHK (thread_db_use_events, | |
9836d6ea | 668 | tdb->td_thr_event_enable_p = dlsym (handle, "td_thr_event_enable")); |
cdbfd419 PP |
669 | |
670 | /* These are not essential. */ | |
9836d6ea PA |
671 | CHK (0, tdb->td_ta_event_addr_p = dlsym (handle, "td_ta_event_addr")); |
672 | CHK (0, tdb->td_ta_set_event_p = dlsym (handle, "td_ta_set_event")); | |
673 | CHK (0, tdb->td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg")); | |
674 | CHK (0, tdb->td_thr_tls_get_addr_p = dlsym (handle, "td_thr_tls_get_addr")); | |
5876f503 | 675 | CHK (0, tdb->td_thr_tlsbase_p = dlsym (handle, "td_thr_tlsbase")); |
cdbfd419 PP |
676 | |
677 | #undef CHK | |
678 | ||
cdbfd419 PP |
679 | return 1; |
680 | } | |
681 | ||
10e86dd7 DE |
682 | #ifdef HAVE_DLADDR |
683 | ||
cdbfd419 PP |
684 | /* Lookup a library in which given symbol resides. |
685 | Note: this is looking in the GDBSERVER process, not in the inferior. | |
686 | Returns library name, or NULL. */ | |
687 | ||
688 | static const char * | |
689 | dladdr_to_soname (const void *addr) | |
690 | { | |
691 | Dl_info info; | |
692 | ||
693 | if (dladdr (addr, &info) != 0) | |
694 | return info.dli_fname; | |
695 | return NULL; | |
696 | } | |
697 | ||
10e86dd7 DE |
698 | #endif |
699 | ||
cdbfd419 PP |
700 | static int |
701 | try_thread_db_load (const char *library) | |
702 | { | |
703 | void *handle; | |
704 | ||
705 | if (debug_threads) | |
87ce2a04 DE |
706 | debug_printf ("Trying host libthread_db library: %s.\n", |
707 | library); | |
cdbfd419 PP |
708 | handle = dlopen (library, RTLD_NOW); |
709 | if (handle == NULL) | |
710 | { | |
711 | if (debug_threads) | |
87ce2a04 | 712 | debug_printf ("dlopen failed: %s.\n", dlerror ()); |
cdbfd419 PP |
713 | return 0; |
714 | } | |
715 | ||
10e86dd7 | 716 | #ifdef HAVE_DLADDR |
cdbfd419 PP |
717 | if (debug_threads && strchr (library, '/') == NULL) |
718 | { | |
719 | void *td_init; | |
720 | ||
721 | td_init = dlsym (handle, "td_init"); | |
722 | if (td_init != NULL) | |
723 | { | |
724 | const char *const libpath = dladdr_to_soname (td_init); | |
725 | ||
726 | if (libpath != NULL) | |
727 | fprintf (stderr, "Host %s resolved to: %s.\n", | |
728 | library, libpath); | |
729 | } | |
730 | } | |
10e86dd7 | 731 | #endif |
cdbfd419 PP |
732 | |
733 | if (try_thread_db_load_1 (handle)) | |
734 | return 1; | |
735 | ||
736 | /* This library "refused" to work on current inferior. */ | |
737 | dlclose (handle); | |
738 | return 0; | |
739 | } | |
740 | ||
98a5dd13 DE |
741 | /* Handle $sdir in libthread-db-search-path. |
742 | Look for libthread_db in the system dirs, or wherever a plain | |
743 | dlopen(file_without_path) will look. | |
744 | The result is true for success. */ | |
745 | ||
cdbfd419 | 746 | static int |
98a5dd13 DE |
747 | try_thread_db_load_from_sdir (void) |
748 | { | |
749 | return try_thread_db_load (LIBTHREAD_DB_SO); | |
750 | } | |
751 | ||
752 | /* Try to load libthread_db from directory DIR of length DIR_LEN. | |
753 | The result is true for success. */ | |
754 | ||
755 | static int | |
756 | try_thread_db_load_from_dir (const char *dir, size_t dir_len) | |
cdbfd419 PP |
757 | { |
758 | char path[PATH_MAX]; | |
98a5dd13 DE |
759 | |
760 | if (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1 > sizeof (path)) | |
761 | { | |
762 | char *cp = xmalloc (dir_len + 1); | |
763 | ||
764 | memcpy (cp, dir, dir_len); | |
765 | cp[dir_len] = '\0'; | |
766 | warning (_("libthread-db-search-path component too long," | |
767 | " ignored: %s."), cp); | |
768 | free (cp); | |
769 | return 0; | |
770 | } | |
771 | ||
772 | memcpy (path, dir, dir_len); | |
773 | path[dir_len] = '/'; | |
774 | strcpy (path + dir_len + 1, LIBTHREAD_DB_SO); | |
775 | return try_thread_db_load (path); | |
776 | } | |
777 | ||
778 | /* Search libthread_db_search_path for libthread_db which "agrees" | |
779 | to work on current inferior. | |
780 | The result is true for success. */ | |
781 | ||
782 | static int | |
783 | thread_db_load_search (void) | |
784 | { | |
e6712ff1 DE |
785 | VEC (char_ptr) *dir_vec; |
786 | char *this_dir; | |
787 | int i, rc = 0; | |
cdbfd419 PP |
788 | |
789 | if (libthread_db_search_path == NULL) | |
790 | libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH); | |
791 | ||
e6712ff1 DE |
792 | dir_vec = dirnames_to_char_ptr_vec (libthread_db_search_path); |
793 | ||
794 | for (i = 0; VEC_iterate (char_ptr, dir_vec, i, this_dir); ++i) | |
cdbfd419 | 795 | { |
e6712ff1 | 796 | const int pdir_len = sizeof ("$pdir") - 1; |
98a5dd13 DE |
797 | size_t this_dir_len; |
798 | ||
e6712ff1 | 799 | this_dir_len = strlen (this_dir); |
cdbfd419 | 800 | |
e6712ff1 DE |
801 | if (strncmp (this_dir, "$pdir", pdir_len) == 0 |
802 | && (this_dir[pdir_len] == '\0' | |
803 | || this_dir[pdir_len] == '/')) | |
98a5dd13 DE |
804 | { |
805 | /* We don't maintain a list of loaded libraries so we don't know | |
806 | where libpthread lives. We *could* fetch the info, but we don't | |
807 | do that yet. Ignore it. */ | |
808 | } | |
e6712ff1 | 809 | else if (strcmp (this_dir, "$sdir") == 0) |
98a5dd13 DE |
810 | { |
811 | if (try_thread_db_load_from_sdir ()) | |
cdbfd419 | 812 | { |
98a5dd13 | 813 | rc = 1; |
cdbfd419 PP |
814 | break; |
815 | } | |
cdbfd419 | 816 | } |
98a5dd13 | 817 | else |
cdbfd419 | 818 | { |
98a5dd13 DE |
819 | if (try_thread_db_load_from_dir (this_dir, this_dir_len)) |
820 | { | |
821 | rc = 1; | |
822 | break; | |
823 | } | |
cdbfd419 PP |
824 | } |
825 | } | |
cdbfd419 | 826 | |
e6712ff1 | 827 | free_char_ptr_vec (dir_vec); |
cdbfd419 | 828 | if (debug_threads) |
87ce2a04 | 829 | debug_printf ("thread_db_load_search returning %d\n", rc); |
cdbfd419 | 830 | return rc; |
dae5f5cf DJ |
831 | } |
832 | ||
96f15937 PP |
833 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
834 | ||
0d62e5e8 | 835 | int |
24a09b5f | 836 | thread_db_init (int use_events) |
0d62e5e8 | 837 | { |
95954743 | 838 | struct process_info *proc = current_process (); |
0d62e5e8 | 839 | |
fd500816 DJ |
840 | /* FIXME drow/2004-10-16: This is the "overall process ID", which |
841 | GNU/Linux calls tgid, "thread group ID". When we support | |
842 | attaching to threads, the original thread may not be the correct | |
843 | thread. We would have to get the process ID from /proc for NPTL. | |
844 | For LinuxThreads we could do something similar: follow the chain | |
845 | of parent processes until we find the highest one we're attached | |
846 | to, and use its tgid. | |
847 | ||
848 | This isn't the only place in gdbserver that assumes that the first | |
849 | process in the list is the thread group leader. */ | |
ea025f5f | 850 | |
24a09b5f DJ |
851 | thread_db_use_events = use_events; |
852 | ||
cdbfd419 | 853 | if (thread_db_load_search ()) |
0d62e5e8 | 854 | { |
24a09b5f | 855 | if (use_events && thread_db_enable_reporting () == 0) |
cdbfd419 PP |
856 | { |
857 | /* Keep trying; maybe event reporting will work later. */ | |
8336d594 | 858 | thread_db_mourn (proc); |
cdbfd419 PP |
859 | return 0; |
860 | } | |
2db9a427 PA |
861 | |
862 | /* It's best to avoid td_ta_thr_iter if possible. That walks | |
863 | data structures in the inferior's address space that may be | |
864 | corrupted, or, if the target is running, the list may change | |
865 | while we walk it. In the latter case, it's possible that a | |
866 | thread exits just at the exact time that causes GDBserver to | |
867 | get stuck in an infinite loop. If the kernel supports clone | |
868 | events, and /proc/PID/task/ exits, then we already know about | |
869 | all threads in the process. When we need info out of | |
870 | thread_db on a given thread (e.g., for TLS), we'll use | |
871 | find_one_thread then. That uses thread_db entry points that | |
872 | do not walk libpthread's thread list, so should be safe, as | |
873 | well as more efficient. */ | |
874 | if (use_events | |
875 | || !linux_proc_task_list_dir_exists (pid_of (proc))) | |
876 | thread_db_find_new_threads (); | |
fd500816 | 877 | thread_db_look_up_symbols (); |
0d62e5e8 | 878 | return 1; |
cdbfd419 | 879 | } |
0d62e5e8 | 880 | |
cdbfd419 PP |
881 | return 0; |
882 | } | |
883 | ||
ca5c370d PA |
884 | static int |
885 | any_thread_of (struct inferior_list_entry *entry, void *args) | |
886 | { | |
887 | int *pid_p = args; | |
888 | ||
889 | if (ptid_get_pid (entry->id) == *pid_p) | |
890 | return 1; | |
891 | ||
892 | return 0; | |
893 | } | |
894 | ||
f9e39928 PA |
895 | static void |
896 | switch_to_process (struct process_info *proc) | |
897 | { | |
898 | int pid = pid_of (proc); | |
899 | ||
0bfdf32f | 900 | current_thread = |
f9e39928 PA |
901 | (struct thread_info *) find_inferior (&all_threads, |
902 | any_thread_of, &pid); | |
903 | } | |
904 | ||
cdbfd419 PP |
905 | /* Disconnect from libthread_db and free resources. */ |
906 | ||
8336d594 PA |
907 | static void |
908 | disable_thread_event_reporting (struct process_info *proc) | |
cdbfd419 | 909 | { |
fe978cb0 | 910 | struct thread_db *thread_db = proc->priv->thread_db; |
cdbfd419 PP |
911 | if (thread_db) |
912 | { | |
21e1bee4 PP |
913 | td_err_e (*td_ta_clear_event_p) (const td_thragent_t *ta, |
914 | td_thr_events_t *event); | |
915 | ||
fd7dd3e6 | 916 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
21e1bee4 | 917 | td_ta_clear_event_p = dlsym (thread_db->handle, "td_ta_clear_event"); |
fd7dd3e6 | 918 | #else |
fd7dd3e6 PA |
919 | td_ta_clear_event_p = &td_ta_clear_event; |
920 | #endif | |
921 | ||
8336d594 | 922 | if (td_ta_clear_event_p != NULL) |
21e1bee4 | 923 | { |
0bfdf32f | 924 | struct thread_info *saved_thread = current_thread; |
21e1bee4 | 925 | td_thr_events_t events; |
8336d594 | 926 | |
f9e39928 | 927 | switch_to_process (proc); |
21e1bee4 | 928 | |
fd7dd3e6 PA |
929 | /* Set the process wide mask saying we aren't interested |
930 | in any events anymore. */ | |
21e1bee4 PP |
931 | td_event_fillset (&events); |
932 | (*td_ta_clear_event_p) (thread_db->thread_agent, &events); | |
8336d594 | 933 | |
0bfdf32f | 934 | current_thread = saved_thread; |
21e1bee4 | 935 | } |
8336d594 PA |
936 | } |
937 | } | |
938 | ||
f9e39928 PA |
939 | static void |
940 | remove_thread_event_breakpoints (struct process_info *proc) | |
941 | { | |
fe978cb0 | 942 | struct thread_db *thread_db = proc->priv->thread_db; |
f9e39928 PA |
943 | |
944 | if (thread_db->td_create_bp != NULL) | |
945 | { | |
0bfdf32f | 946 | struct thread_info *saved_thread = current_thread; |
f9e39928 PA |
947 | |
948 | switch_to_process (proc); | |
949 | ||
950 | delete_breakpoint (thread_db->td_create_bp); | |
951 | thread_db->td_create_bp = NULL; | |
952 | ||
0bfdf32f | 953 | current_thread = saved_thread; |
f9e39928 PA |
954 | } |
955 | } | |
956 | ||
8336d594 PA |
957 | void |
958 | thread_db_detach (struct process_info *proc) | |
959 | { | |
fe978cb0 | 960 | struct thread_db *thread_db = proc->priv->thread_db; |
f9e39928 PA |
961 | |
962 | if (thread_db) | |
963 | { | |
964 | disable_thread_event_reporting (proc); | |
965 | remove_thread_event_breakpoints (proc); | |
966 | } | |
8336d594 PA |
967 | } |
968 | ||
969 | /* Disconnect from libthread_db and free resources. */ | |
970 | ||
971 | void | |
972 | thread_db_mourn (struct process_info *proc) | |
973 | { | |
fe978cb0 | 974 | struct thread_db *thread_db = proc->priv->thread_db; |
8336d594 PA |
975 | if (thread_db) |
976 | { | |
977 | td_err_e (*td_ta_delete_p) (td_thragent_t *); | |
978 | ||
979 | #ifndef USE_LIBTHREAD_DB_DIRECTLY | |
980 | td_ta_delete_p = dlsym (thread_db->handle, "td_ta_delete"); | |
981 | #else | |
982 | td_ta_delete_p = &td_ta_delete; | |
983 | #endif | |
cdbfd419 | 984 | |
cdbfd419 PP |
985 | if (td_ta_delete_p != NULL) |
986 | (*td_ta_delete_p) (thread_db->thread_agent); | |
987 | ||
fd7dd3e6 | 988 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 | 989 | dlclose (thread_db->handle); |
96f15937 PP |
990 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
991 | ||
cdbfd419 | 992 | free (thread_db); |
fe978cb0 | 993 | proc->priv->thread_db = NULL; |
cdbfd419 PP |
994 | } |
995 | } | |
996 | ||
997 | /* Handle "set libthread-db-search-path" monitor command and return 1. | |
998 | For any other command, return 0. */ | |
999 | ||
1000 | int | |
1001 | thread_db_handle_monitor_command (char *mon) | |
1002 | { | |
84e578fb DE |
1003 | const char *cmd = "set libthread-db-search-path"; |
1004 | size_t cmd_len = strlen (cmd); | |
1005 | ||
1006 | if (strncmp (mon, cmd, cmd_len) == 0 | |
1007 | && (mon[cmd_len] == '\0' | |
1008 | || mon[cmd_len] == ' ')) | |
cdbfd419 | 1009 | { |
84e578fb | 1010 | const char *cp = mon + cmd_len; |
cdbfd419 PP |
1011 | |
1012 | if (libthread_db_search_path != NULL) | |
1013 | free (libthread_db_search_path); | |
1014 | ||
1015 | /* Skip leading space (if any). */ | |
1016 | while (isspace (*cp)) | |
1017 | ++cp; | |
1018 | ||
84e578fb DE |
1019 | if (*cp == '\0') |
1020 | cp = LIBTHREAD_DB_SEARCH_PATH; | |
cdbfd419 PP |
1021 | libthread_db_search_path = xstrdup (cp); |
1022 | ||
1023 | monitor_output ("libthread-db-search-path set to `"); | |
1024 | monitor_output (libthread_db_search_path); | |
1025 | monitor_output ("'\n"); | |
1026 | return 1; | |
0d62e5e8 DJ |
1027 | } |
1028 | ||
cdbfd419 | 1029 | /* Tell server.c to perform default processing. */ |
0d62e5e8 DJ |
1030 | return 0; |
1031 | } |