Commit | Line | Data |
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0d62e5e8 | 1 | /* Thread management interface, for the remote server for GDB. |
618f726f | 2 | Copyright (C) 2002-2016 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 | ||
0050a760 | 27 | #include "gdb_proc_service.h" |
125f8a3d | 28 | #include "nat/gdb_thread_db.h" |
e6712ff1 | 29 | #include "gdb_vecs.h" |
2db9a427 | 30 | #include "nat/linux-procfs.h" |
0d62e5e8 | 31 | |
96f15937 | 32 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 | 33 | #include <dlfcn.h> |
96f15937 | 34 | #endif |
cdbfd419 PP |
35 | #include <limits.h> |
36 | #include <ctype.h> | |
37 | ||
38 | struct thread_db | |
39 | { | |
40 | /* Structure that identifies the child process for the | |
41 | <proc_service.h> interface. */ | |
42 | struct ps_prochandle proc_handle; | |
43 | ||
44 | /* Connection to the libthread_db library. */ | |
45 | td_thragent_t *thread_agent; | |
46 | ||
9836d6ea PA |
47 | /* If this flag has been set, we've already asked GDB for all |
48 | symbols we might need; assume symbol cache misses are | |
49 | failures. */ | |
50 | int all_symbols_looked_up; | |
51 | ||
96f15937 | 52 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 PP |
53 | /* Handle of the libthread_db from dlopen. */ |
54 | void *handle; | |
96f15937 | 55 | #endif |
cdbfd419 PP |
56 | |
57 | /* Addresses of libthread_db functions. */ | |
96e9210f PA |
58 | td_ta_new_ftype *td_ta_new_p; |
59 | td_ta_event_getmsg_ftype * td_ta_event_getmsg_p; | |
60 | td_ta_set_event_ftype *td_ta_set_event_p; | |
61 | td_ta_event_addr_ftype *td_ta_event_addr_p; | |
62 | td_ta_map_lwp2thr_ftype *td_ta_map_lwp2thr_p; | |
63 | td_thr_get_info_ftype *td_thr_get_info_p; | |
96e9210f PA |
64 | td_ta_thr_iter_ftype *td_ta_thr_iter_p; |
65 | td_thr_tls_get_addr_ftype *td_thr_tls_get_addr_p; | |
66 | td_thr_tlsbase_ftype *td_thr_tlsbase_p; | |
67 | td_symbol_list_ftype *td_symbol_list_p; | |
cdbfd419 PP |
68 | }; |
69 | ||
70 | static char *libthread_db_search_path; | |
186947f7 | 71 | |
95954743 | 72 | static int find_one_thread (ptid_t); |
0d62e5e8 DJ |
73 | static int find_new_threads_callback (const td_thrhandle_t *th_p, void *data); |
74 | ||
54363045 | 75 | static const char * |
0d62e5e8 DJ |
76 | thread_db_err_str (td_err_e err) |
77 | { | |
78 | static char buf[64]; | |
79 | ||
80 | switch (err) | |
81 | { | |
82 | case TD_OK: | |
83 | return "generic 'call succeeded'"; | |
84 | case TD_ERR: | |
85 | return "generic error"; | |
86 | case TD_NOTHR: | |
87 | return "no thread to satisfy query"; | |
88 | case TD_NOSV: | |
89 | return "no sync handle to satisfy query"; | |
90 | case TD_NOLWP: | |
91 | return "no LWP to satisfy query"; | |
92 | case TD_BADPH: | |
93 | return "invalid process handle"; | |
94 | case TD_BADTH: | |
95 | return "invalid thread handle"; | |
96 | case TD_BADSH: | |
97 | return "invalid synchronization handle"; | |
98 | case TD_BADTA: | |
99 | return "invalid thread agent"; | |
100 | case TD_BADKEY: | |
101 | return "invalid key"; | |
102 | case TD_NOMSG: | |
103 | return "no event message for getmsg"; | |
104 | case TD_NOFPREGS: | |
105 | return "FPU register set not available"; | |
106 | case TD_NOLIBTHREAD: | |
107 | return "application not linked with libthread"; | |
108 | case TD_NOEVENT: | |
109 | return "requested event is not supported"; | |
110 | case TD_NOCAPAB: | |
111 | return "capability not available"; | |
112 | case TD_DBERR: | |
113 | return "debugger service failed"; | |
114 | case TD_NOAPLIC: | |
115 | return "operation not applicable to"; | |
116 | case TD_NOTSD: | |
117 | return "no thread-specific data for this thread"; | |
118 | case TD_MALLOC: | |
119 | return "malloc failed"; | |
120 | case TD_PARTIALREG: | |
121 | return "only part of register set was written/read"; | |
122 | case TD_NOXREGS: | |
123 | return "X register set not available for this thread"; | |
3db0444b DJ |
124 | #ifdef HAVE_TD_VERSION |
125 | case TD_VERSION: | |
126 | return "version mismatch between libthread_db and libpthread"; | |
127 | #endif | |
0d62e5e8 | 128 | default: |
6cebaf6e | 129 | xsnprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
0d62e5e8 DJ |
130 | return buf; |
131 | } | |
132 | } | |
133 | ||
134 | #if 0 | |
135 | static char * | |
136 | thread_db_state_str (td_thr_state_e state) | |
137 | { | |
138 | static char buf[64]; | |
139 | ||
140 | switch (state) | |
141 | { | |
142 | case TD_THR_STOPPED: | |
143 | return "stopped by debugger"; | |
144 | case TD_THR_RUN: | |
145 | return "runnable"; | |
146 | case TD_THR_ACTIVE: | |
147 | return "active"; | |
148 | case TD_THR_ZOMBIE: | |
149 | return "zombie"; | |
150 | case TD_THR_SLEEP: | |
151 | return "sleeping"; | |
152 | case TD_THR_STOPPED_ASLEEP: | |
153 | return "stopped by debugger AND blocked"; | |
154 | default: | |
6cebaf6e | 155 | xsnprintf (buf, sizeof (buf), "unknown thread_db state %d", state); |
0d62e5e8 DJ |
156 | return buf; |
157 | } | |
158 | } | |
159 | #endif | |
160 | ||
ae13219e | 161 | static int |
95954743 | 162 | find_one_thread (ptid_t ptid) |
0d62e5e8 | 163 | { |
ae13219e DJ |
164 | td_thrhandle_t th; |
165 | td_thrinfo_t ti; | |
0d62e5e8 DJ |
166 | td_err_e err; |
167 | struct thread_info *inferior; | |
54a0b537 | 168 | struct lwp_info *lwp; |
fe978cb0 | 169 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
95954743 | 170 | int lwpid = ptid_get_lwp (ptid); |
0d62e5e8 | 171 | |
95954743 | 172 | inferior = (struct thread_info *) find_inferior_id (&all_threads, ptid); |
54a0b537 PA |
173 | lwp = get_thread_lwp (inferior); |
174 | if (lwp->thread_known) | |
ae13219e DJ |
175 | return 1; |
176 | ||
24a09b5f | 177 | /* Get information about this thread. */ |
cdbfd419 | 178 | err = thread_db->td_ta_map_lwp2thr_p (thread_db->thread_agent, lwpid, &th); |
ae13219e | 179 | if (err != TD_OK) |
24a09b5f DJ |
180 | error ("Cannot get thread handle for LWP %d: %s", |
181 | lwpid, thread_db_err_str (err)); | |
ae13219e | 182 | |
cdbfd419 | 183 | err = thread_db->td_thr_get_info_p (&th, &ti); |
ae13219e | 184 | if (err != TD_OK) |
24a09b5f DJ |
185 | error ("Cannot get thread info for LWP %d: %s", |
186 | lwpid, thread_db_err_str (err)); | |
ae13219e DJ |
187 | |
188 | if (debug_threads) | |
87ce2a04 | 189 | debug_printf ("Found thread %ld (LWP %d)\n", |
d41401ac | 190 | (unsigned long) ti.ti_tid, ti.ti_lid); |
ae13219e | 191 | |
95954743 | 192 | if (lwpid != ti.ti_lid) |
24a09b5f DJ |
193 | { |
194 | warning ("PID mismatch! Expected %ld, got %ld", | |
95954743 | 195 | (long) lwpid, (long) ti.ti_lid); |
24a09b5f DJ |
196 | return 0; |
197 | } | |
ae13219e | 198 | |
24a09b5f DJ |
199 | /* If the new thread ID is zero, a final thread ID will be available |
200 | later. Do not enable thread debugging yet. */ | |
201 | if (ti.ti_tid == 0) | |
202 | return 0; | |
ae13219e | 203 | |
54a0b537 PA |
204 | lwp->thread_known = 1; |
205 | lwp->th = th; | |
ae13219e | 206 | |
ae13219e DJ |
207 | return 1; |
208 | } | |
209 | ||
5f7d1694 PP |
210 | /* Attach a thread. Return true on success. */ |
211 | ||
212 | static int | |
213 | attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p) | |
ae13219e | 214 | { |
7ae1a6a6 PA |
215 | struct process_info *proc = current_process (); |
216 | int pid = pid_of (proc); | |
217 | ptid_t ptid = ptid_build (pid, ti_p->ti_lid, 0); | |
54a0b537 | 218 | struct lwp_info *lwp; |
7ae1a6a6 | 219 | int err; |
ae13219e | 220 | |
0d62e5e8 | 221 | if (debug_threads) |
87ce2a04 | 222 | debug_printf ("Attaching to thread %ld (LWP %d)\n", |
d41401ac | 223 | (unsigned long) ti_p->ti_tid, ti_p->ti_lid); |
7ae1a6a6 PA |
224 | err = linux_attach_lwp (ptid); |
225 | if (err != 0) | |
0d62e5e8 | 226 | { |
7ae1a6a6 | 227 | warning ("Could not attach to thread %ld (LWP %d): %s\n", |
d41401ac | 228 | (unsigned long) ti_p->ti_tid, ti_p->ti_lid, |
8784d563 | 229 | linux_ptrace_attach_fail_reason_string (ptid, err)); |
5f7d1694 | 230 | return 0; |
0d62e5e8 DJ |
231 | } |
232 | ||
7ae1a6a6 PA |
233 | lwp = find_lwp_pid (ptid); |
234 | gdb_assert (lwp != NULL); | |
54a0b537 PA |
235 | lwp->thread_known = 1; |
236 | lwp->th = *th_p; | |
24a09b5f | 237 | |
5f7d1694 PP |
238 | return 1; |
239 | } | |
240 | ||
241 | /* Attach thread if we haven't seen it yet. | |
242 | Increment *COUNTER if we have attached a new thread. | |
243 | Return false on failure. */ | |
244 | ||
245 | static int | |
246 | maybe_attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p, | |
247 | int *counter) | |
248 | { | |
249 | struct lwp_info *lwp; | |
250 | ||
251 | lwp = find_lwp_pid (pid_to_ptid (ti_p->ti_lid)); | |
252 | if (lwp != NULL) | |
253 | return 1; | |
254 | ||
255 | if (!attach_thread (th_p, ti_p)) | |
256 | return 0; | |
257 | ||
258 | if (counter != NULL) | |
259 | *counter += 1; | |
260 | ||
261 | return 1; | |
0d62e5e8 DJ |
262 | } |
263 | ||
264 | static int | |
265 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) | |
266 | { | |
267 | td_thrinfo_t ti; | |
268 | td_err_e err; | |
fe978cb0 | 269 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
0d62e5e8 | 270 | |
cdbfd419 | 271 | err = thread_db->td_thr_get_info_p (th_p, &ti); |
0d62e5e8 DJ |
272 | if (err != TD_OK) |
273 | error ("Cannot get thread info: %s", thread_db_err_str (err)); | |
274 | ||
a33e3959 PA |
275 | if (ti.ti_lid == -1) |
276 | { | |
277 | /* A thread with kernel thread ID -1 is either a thread that | |
278 | exited and was joined, or a thread that is being created but | |
279 | hasn't started yet, and that is reusing the tcb/stack of a | |
280 | thread that previously exited and was joined. (glibc marks | |
281 | terminated and joined threads with kernel thread ID -1. See | |
282 | glibc PR17707. */ | |
d6c146e9 PA |
283 | if (debug_threads) |
284 | debug_printf ("thread_db: skipping exited and " | |
d41401ac DE |
285 | "joined thread (0x%lx)\n", |
286 | (unsigned long) ti.ti_tid); | |
a33e3959 PA |
287 | return 0; |
288 | } | |
289 | ||
0d62e5e8 DJ |
290 | /* Check for zombies. */ |
291 | if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE) | |
292 | return 0; | |
293 | ||
5f7d1694 PP |
294 | if (!maybe_attach_thread (th_p, &ti, (int *) data)) |
295 | { | |
296 | /* Terminate iteration early: we might be looking at stale data in | |
297 | the inferior. The thread_db_find_new_threads will retry. */ | |
298 | return 1; | |
299 | } | |
0d62e5e8 DJ |
300 | |
301 | return 0; | |
302 | } | |
303 | ||
304 | static void | |
305 | thread_db_find_new_threads (void) | |
306 | { | |
307 | td_err_e err; | |
fbd5db48 | 308 | ptid_t ptid = current_ptid; |
fe978cb0 | 309 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
5f7d1694 | 310 | int loop, iteration; |
0d62e5e8 | 311 | |
ae13219e DJ |
312 | /* This function is only called when we first initialize thread_db. |
313 | First locate the initial thread. If it is not ready for | |
314 | debugging yet, then stop. */ | |
95954743 | 315 | if (find_one_thread (ptid) == 0) |
ae13219e DJ |
316 | return; |
317 | ||
5f7d1694 PP |
318 | /* Require 4 successive iterations which do not find any new threads. |
319 | The 4 is a heuristic: there is an inherent race here, and I have | |
320 | seen that 2 iterations in a row are not always sufficient to | |
321 | "capture" all threads. */ | |
322 | for (loop = 0, iteration = 0; loop < 4; ++loop, ++iteration) | |
323 | { | |
324 | int new_thread_count = 0; | |
325 | ||
326 | /* Iterate over all user-space threads to discover new threads. */ | |
327 | err = thread_db->td_ta_thr_iter_p (thread_db->thread_agent, | |
328 | find_new_threads_callback, | |
329 | &new_thread_count, | |
493e2a69 MS |
330 | TD_THR_ANY_STATE, |
331 | TD_THR_LOWEST_PRIORITY, | |
5f7d1694 PP |
332 | TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS); |
333 | if (debug_threads) | |
87ce2a04 DE |
334 | debug_printf ("Found %d threads in iteration %d.\n", |
335 | new_thread_count, iteration); | |
5f7d1694 PP |
336 | |
337 | if (new_thread_count != 0) | |
338 | { | |
339 | /* Found new threads. Restart iteration from beginning. */ | |
340 | loop = -1; | |
341 | } | |
342 | } | |
0d62e5e8 DJ |
343 | if (err != TD_OK) |
344 | error ("Cannot find new threads: %s", thread_db_err_str (err)); | |
345 | } | |
346 | ||
fd500816 DJ |
347 | /* Cache all future symbols that thread_db might request. We can not |
348 | request symbols at arbitrary states in the remote protocol, only | |
349 | when the client tells us that new symbols are available. So when | |
350 | we load the thread library, make sure to check the entire list. */ | |
351 | ||
352 | static void | |
353 | thread_db_look_up_symbols (void) | |
354 | { | |
fe978cb0 | 355 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
cdbfd419 | 356 | const char **sym_list; |
fd500816 DJ |
357 | CORE_ADDR unused; |
358 | ||
cdbfd419 | 359 | for (sym_list = thread_db->td_symbol_list_p (); *sym_list; sym_list++) |
9836d6ea PA |
360 | look_up_one_symbol (*sym_list, &unused, 1); |
361 | ||
362 | /* We're not interested in any other libraries loaded after this | |
363 | point, only in symbols in libpthread.so. */ | |
364 | thread_db->all_symbols_looked_up = 1; | |
365 | } | |
366 | ||
367 | int | |
368 | thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp) | |
369 | { | |
fe978cb0 | 370 | struct thread_db *thread_db = current_process ()->priv->thread_db; |
9836d6ea PA |
371 | int may_ask_gdb = !thread_db->all_symbols_looked_up; |
372 | ||
373 | /* If we've passed the call to thread_db_look_up_symbols, then | |
374 | anything not in the cache must not exist; we're not interested | |
375 | in any libraries loaded after that point, only in symbols in | |
376 | libpthread.so. It might not be an appropriate time to look | |
377 | up a symbol, e.g. while we're trying to fetch registers. */ | |
378 | return look_up_one_symbol (name, addrp, may_ask_gdb); | |
fd500816 DJ |
379 | } |
380 | ||
dae5f5cf DJ |
381 | int |
382 | thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset, | |
383 | CORE_ADDR load_module, CORE_ADDR *address) | |
384 | { | |
dae5f5cf DJ |
385 | psaddr_t addr; |
386 | td_err_e err; | |
54a0b537 | 387 | struct lwp_info *lwp; |
0bfdf32f | 388 | struct thread_info *saved_thread; |
cdbfd419 PP |
389 | struct process_info *proc; |
390 | struct thread_db *thread_db; | |
391 | ||
392 | proc = get_thread_process (thread); | |
fe978cb0 | 393 | thread_db = proc->priv->thread_db; |
dae5f5cf | 394 | |
7fe519cb | 395 | /* If the thread layer is not (yet) initialized, fail. */ |
8a4ac37e | 396 | if (thread_db == NULL || !thread_db->all_symbols_looked_up) |
7fe519cb UW |
397 | return TD_ERR; |
398 | ||
5876f503 JK |
399 | /* If td_thr_tls_get_addr is missing rather do not expect td_thr_tlsbase |
400 | could work. */ | |
401 | if (thread_db->td_thr_tls_get_addr_p == NULL | |
402 | || (load_module == 0 && thread_db->td_thr_tlsbase_p == NULL)) | |
cdbfd419 PP |
403 | return -1; |
404 | ||
54a0b537 PA |
405 | lwp = get_thread_lwp (thread); |
406 | if (!lwp->thread_known) | |
80894984 | 407 | find_one_thread (thread->entry.id); |
54a0b537 | 408 | if (!lwp->thread_known) |
dae5f5cf DJ |
409 | return TD_NOTHR; |
410 | ||
0bfdf32f GB |
411 | saved_thread = current_thread; |
412 | current_thread = thread; | |
5876f503 JK |
413 | |
414 | if (load_module != 0) | |
415 | { | |
416 | /* Note the cast through uintptr_t: this interface only works if | |
417 | a target address fits in a psaddr_t, which is a host pointer. | |
418 | So a 32-bit debugger can not access 64-bit TLS through this. */ | |
419 | err = thread_db->td_thr_tls_get_addr_p (&lwp->th, | |
420 | (psaddr_t) (uintptr_t) load_module, | |
421 | offset, &addr); | |
422 | } | |
423 | else | |
424 | { | |
425 | /* This code path handles the case of -static -pthread executables: | |
426 | https://sourceware.org/ml/libc-help/2014-03/msg00024.html | |
427 | For older GNU libc r_debug.r_map is NULL. For GNU libc after | |
428 | PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL. | |
429 | The constant number 1 depends on GNU __libc_setup_tls | |
430 | initialization of l_tls_modid to 1. */ | |
431 | err = thread_db->td_thr_tlsbase_p (&lwp->th, 1, &addr); | |
432 | addr = (char *) addr + offset; | |
433 | } | |
434 | ||
0bfdf32f | 435 | current_thread = saved_thread; |
dae5f5cf DJ |
436 | if (err == TD_OK) |
437 | { | |
186947f7 | 438 | *address = (CORE_ADDR) (uintptr_t) addr; |
dae5f5cf DJ |
439 | return 0; |
440 | } | |
441 | else | |
442 | return err; | |
cdbfd419 PP |
443 | } |
444 | ||
96f15937 PP |
445 | #ifdef USE_LIBTHREAD_DB_DIRECTLY |
446 | ||
447 | static int | |
448 | thread_db_load_search (void) | |
449 | { | |
450 | td_err_e err; | |
9836d6ea | 451 | struct thread_db *tdb; |
96f15937 PP |
452 | struct process_info *proc = current_process (); |
453 | ||
fe978cb0 | 454 | gdb_assert (proc->priv->thread_db == NULL); |
96f15937 | 455 | |
8d749320 | 456 | tdb = XCNEW (struct thread_db); |
fe978cb0 | 457 | proc->priv->thread_db = tdb; |
f9e39928 | 458 | |
9836d6ea | 459 | tdb->td_ta_new_p = &td_ta_new; |
96f15937 PP |
460 | |
461 | /* Attempt to open a connection to the thread library. */ | |
9836d6ea | 462 | err = tdb->td_ta_new_p (&tdb->proc_handle, &tdb->thread_agent); |
96f15937 PP |
463 | if (err != TD_OK) |
464 | { | |
465 | if (debug_threads) | |
87ce2a04 | 466 | debug_printf ("td_ta_new(): %s\n", thread_db_err_str (err)); |
9836d6ea | 467 | free (tdb); |
fe978cb0 | 468 | proc->priv->thread_db = NULL; |
96f15937 PP |
469 | return 0; |
470 | } | |
471 | ||
9836d6ea PA |
472 | tdb->td_ta_map_lwp2thr_p = &td_ta_map_lwp2thr; |
473 | tdb->td_thr_get_info_p = &td_thr_get_info; | |
474 | tdb->td_ta_thr_iter_p = &td_ta_thr_iter; | |
475 | tdb->td_symbol_list_p = &td_symbol_list; | |
96f15937 | 476 | |
96f15937 | 477 | /* These are not essential. */ |
9836d6ea PA |
478 | tdb->td_ta_event_addr_p = &td_ta_event_addr; |
479 | tdb->td_ta_set_event_p = &td_ta_set_event; | |
480 | tdb->td_ta_event_getmsg_p = &td_ta_event_getmsg; | |
481 | tdb->td_thr_tls_get_addr_p = &td_thr_tls_get_addr; | |
5876f503 | 482 | tdb->td_thr_tlsbase_p = &td_thr_tlsbase; |
96f15937 PP |
483 | |
484 | return 1; | |
485 | } | |
486 | ||
487 | #else | |
488 | ||
cdbfd419 PP |
489 | static int |
490 | try_thread_db_load_1 (void *handle) | |
491 | { | |
492 | td_err_e err; | |
9836d6ea | 493 | struct thread_db *tdb; |
cdbfd419 PP |
494 | struct process_info *proc = current_process (); |
495 | ||
fe978cb0 | 496 | gdb_assert (proc->priv->thread_db == NULL); |
cdbfd419 | 497 | |
8d749320 | 498 | tdb = XCNEW (struct thread_db); |
fe978cb0 | 499 | proc->priv->thread_db = tdb; |
f9e39928 | 500 | |
9836d6ea | 501 | tdb->handle = handle; |
cdbfd419 PP |
502 | |
503 | /* Initialize pointers to the dynamic library functions we will use. | |
504 | Essential functions first. */ | |
505 | ||
506 | #define CHK(required, a) \ | |
507 | do \ | |
508 | { \ | |
509 | if ((a) == NULL) \ | |
510 | { \ | |
511 | if (debug_threads) \ | |
87ce2a04 | 512 | debug_printf ("dlsym: %s\n", dlerror ()); \ |
cdbfd419 | 513 | if (required) \ |
9836d6ea PA |
514 | { \ |
515 | free (tdb); \ | |
fe978cb0 | 516 | proc->priv->thread_db = NULL; \ |
9836d6ea PA |
517 | return 0; \ |
518 | } \ | |
cdbfd419 PP |
519 | } \ |
520 | } \ | |
521 | while (0) | |
522 | ||
96e9210f PA |
523 | #define TDB_DLSYM(tdb, func) \ |
524 | tdb->func ## _p = (func ## _ftype *) dlsym (tdb->handle, #func) | |
525 | ||
526 | CHK (1, TDB_DLSYM (tdb, td_ta_new)); | |
cdbfd419 PP |
527 | |
528 | /* Attempt to open a connection to the thread library. */ | |
9836d6ea | 529 | err = tdb->td_ta_new_p (&tdb->proc_handle, &tdb->thread_agent); |
cdbfd419 PP |
530 | if (err != TD_OK) |
531 | { | |
532 | if (debug_threads) | |
87ce2a04 | 533 | debug_printf ("td_ta_new(): %s\n", thread_db_err_str (err)); |
9836d6ea | 534 | free (tdb); |
fe978cb0 | 535 | proc->priv->thread_db = NULL; |
cdbfd419 PP |
536 | return 0; |
537 | } | |
538 | ||
96e9210f PA |
539 | CHK (1, TDB_DLSYM (tdb, td_ta_map_lwp2thr)); |
540 | CHK (1, TDB_DLSYM (tdb, td_thr_get_info)); | |
541 | CHK (1, TDB_DLSYM (tdb, td_ta_thr_iter)); | |
542 | CHK (1, TDB_DLSYM (tdb, td_symbol_list)); | |
cdbfd419 | 543 | |
cdbfd419 | 544 | /* These are not essential. */ |
96e9210f PA |
545 | CHK (0, TDB_DLSYM (tdb, td_ta_event_addr)); |
546 | CHK (0, TDB_DLSYM (tdb, td_ta_set_event)); | |
547 | CHK (0, TDB_DLSYM (tdb, td_ta_event_getmsg)); | |
548 | CHK (0, TDB_DLSYM (tdb, td_thr_tls_get_addr)); | |
549 | CHK (0, TDB_DLSYM (tdb, td_thr_tlsbase)); | |
cdbfd419 PP |
550 | |
551 | #undef CHK | |
96e9210f | 552 | #undef TDB_DLSYM |
cdbfd419 | 553 | |
cdbfd419 PP |
554 | return 1; |
555 | } | |
556 | ||
10e86dd7 DE |
557 | #ifdef HAVE_DLADDR |
558 | ||
cdbfd419 PP |
559 | /* Lookup a library in which given symbol resides. |
560 | Note: this is looking in the GDBSERVER process, not in the inferior. | |
561 | Returns library name, or NULL. */ | |
562 | ||
563 | static const char * | |
564 | dladdr_to_soname (const void *addr) | |
565 | { | |
566 | Dl_info info; | |
567 | ||
568 | if (dladdr (addr, &info) != 0) | |
569 | return info.dli_fname; | |
570 | return NULL; | |
571 | } | |
572 | ||
10e86dd7 DE |
573 | #endif |
574 | ||
cdbfd419 PP |
575 | static int |
576 | try_thread_db_load (const char *library) | |
577 | { | |
578 | void *handle; | |
579 | ||
580 | if (debug_threads) | |
87ce2a04 DE |
581 | debug_printf ("Trying host libthread_db library: %s.\n", |
582 | library); | |
cdbfd419 PP |
583 | handle = dlopen (library, RTLD_NOW); |
584 | if (handle == NULL) | |
585 | { | |
586 | if (debug_threads) | |
87ce2a04 | 587 | debug_printf ("dlopen failed: %s.\n", dlerror ()); |
cdbfd419 PP |
588 | return 0; |
589 | } | |
590 | ||
10e86dd7 | 591 | #ifdef HAVE_DLADDR |
cdbfd419 PP |
592 | if (debug_threads && strchr (library, '/') == NULL) |
593 | { | |
594 | void *td_init; | |
595 | ||
596 | td_init = dlsym (handle, "td_init"); | |
597 | if (td_init != NULL) | |
598 | { | |
599 | const char *const libpath = dladdr_to_soname (td_init); | |
600 | ||
601 | if (libpath != NULL) | |
602 | fprintf (stderr, "Host %s resolved to: %s.\n", | |
603 | library, libpath); | |
604 | } | |
605 | } | |
10e86dd7 | 606 | #endif |
cdbfd419 PP |
607 | |
608 | if (try_thread_db_load_1 (handle)) | |
609 | return 1; | |
610 | ||
611 | /* This library "refused" to work on current inferior. */ | |
612 | dlclose (handle); | |
613 | return 0; | |
614 | } | |
615 | ||
98a5dd13 DE |
616 | /* Handle $sdir in libthread-db-search-path. |
617 | Look for libthread_db in the system dirs, or wherever a plain | |
618 | dlopen(file_without_path) will look. | |
619 | The result is true for success. */ | |
620 | ||
cdbfd419 | 621 | static int |
98a5dd13 DE |
622 | try_thread_db_load_from_sdir (void) |
623 | { | |
624 | return try_thread_db_load (LIBTHREAD_DB_SO); | |
625 | } | |
626 | ||
627 | /* Try to load libthread_db from directory DIR of length DIR_LEN. | |
628 | The result is true for success. */ | |
629 | ||
630 | static int | |
631 | try_thread_db_load_from_dir (const char *dir, size_t dir_len) | |
cdbfd419 PP |
632 | { |
633 | char path[PATH_MAX]; | |
98a5dd13 DE |
634 | |
635 | if (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1 > sizeof (path)) | |
636 | { | |
224c3ddb | 637 | char *cp = (char *) xmalloc (dir_len + 1); |
98a5dd13 DE |
638 | |
639 | memcpy (cp, dir, dir_len); | |
640 | cp[dir_len] = '\0'; | |
641 | warning (_("libthread-db-search-path component too long," | |
642 | " ignored: %s."), cp); | |
643 | free (cp); | |
644 | return 0; | |
645 | } | |
646 | ||
647 | memcpy (path, dir, dir_len); | |
648 | path[dir_len] = '/'; | |
649 | strcpy (path + dir_len + 1, LIBTHREAD_DB_SO); | |
650 | return try_thread_db_load (path); | |
651 | } | |
652 | ||
653 | /* Search libthread_db_search_path for libthread_db which "agrees" | |
654 | to work on current inferior. | |
655 | The result is true for success. */ | |
656 | ||
657 | static int | |
658 | thread_db_load_search (void) | |
659 | { | |
e6712ff1 DE |
660 | VEC (char_ptr) *dir_vec; |
661 | char *this_dir; | |
662 | int i, rc = 0; | |
cdbfd419 PP |
663 | |
664 | if (libthread_db_search_path == NULL) | |
665 | libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH); | |
666 | ||
e6712ff1 DE |
667 | dir_vec = dirnames_to_char_ptr_vec (libthread_db_search_path); |
668 | ||
669 | for (i = 0; VEC_iterate (char_ptr, dir_vec, i, this_dir); ++i) | |
cdbfd419 | 670 | { |
e6712ff1 | 671 | const int pdir_len = sizeof ("$pdir") - 1; |
98a5dd13 DE |
672 | size_t this_dir_len; |
673 | ||
e6712ff1 | 674 | this_dir_len = strlen (this_dir); |
cdbfd419 | 675 | |
e6712ff1 DE |
676 | if (strncmp (this_dir, "$pdir", pdir_len) == 0 |
677 | && (this_dir[pdir_len] == '\0' | |
678 | || this_dir[pdir_len] == '/')) | |
98a5dd13 DE |
679 | { |
680 | /* We don't maintain a list of loaded libraries so we don't know | |
681 | where libpthread lives. We *could* fetch the info, but we don't | |
682 | do that yet. Ignore it. */ | |
683 | } | |
e6712ff1 | 684 | else if (strcmp (this_dir, "$sdir") == 0) |
98a5dd13 DE |
685 | { |
686 | if (try_thread_db_load_from_sdir ()) | |
cdbfd419 | 687 | { |
98a5dd13 | 688 | rc = 1; |
cdbfd419 PP |
689 | break; |
690 | } | |
cdbfd419 | 691 | } |
98a5dd13 | 692 | else |
cdbfd419 | 693 | { |
98a5dd13 DE |
694 | if (try_thread_db_load_from_dir (this_dir, this_dir_len)) |
695 | { | |
696 | rc = 1; | |
697 | break; | |
698 | } | |
cdbfd419 PP |
699 | } |
700 | } | |
cdbfd419 | 701 | |
e6712ff1 | 702 | free_char_ptr_vec (dir_vec); |
cdbfd419 | 703 | if (debug_threads) |
87ce2a04 | 704 | debug_printf ("thread_db_load_search returning %d\n", rc); |
cdbfd419 | 705 | return rc; |
dae5f5cf DJ |
706 | } |
707 | ||
96f15937 PP |
708 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
709 | ||
0d62e5e8 | 710 | int |
9b4c5f87 | 711 | thread_db_init (void) |
0d62e5e8 | 712 | { |
95954743 | 713 | struct process_info *proc = current_process (); |
0d62e5e8 | 714 | |
fd500816 DJ |
715 | /* FIXME drow/2004-10-16: This is the "overall process ID", which |
716 | GNU/Linux calls tgid, "thread group ID". When we support | |
717 | attaching to threads, the original thread may not be the correct | |
718 | thread. We would have to get the process ID from /proc for NPTL. | |
fd500816 DJ |
719 | |
720 | This isn't the only place in gdbserver that assumes that the first | |
721 | process in the list is the thread group leader. */ | |
ea025f5f | 722 | |
cdbfd419 | 723 | if (thread_db_load_search ()) |
0d62e5e8 | 724 | { |
2db9a427 PA |
725 | /* It's best to avoid td_ta_thr_iter if possible. That walks |
726 | data structures in the inferior's address space that may be | |
727 | corrupted, or, if the target is running, the list may change | |
728 | while we walk it. In the latter case, it's possible that a | |
729 | thread exits just at the exact time that causes GDBserver to | |
9b4c5f87 AT |
730 | get stuck in an infinite loop. As the kernel supports clone |
731 | events and /proc/PID/task/ exists, then we already know about | |
2db9a427 PA |
732 | all threads in the process. When we need info out of |
733 | thread_db on a given thread (e.g., for TLS), we'll use | |
734 | find_one_thread then. That uses thread_db entry points that | |
735 | do not walk libpthread's thread list, so should be safe, as | |
736 | well as more efficient. */ | |
9b4c5f87 | 737 | if (!linux_proc_task_list_dir_exists (pid_of (proc))) |
2db9a427 | 738 | thread_db_find_new_threads (); |
fd500816 | 739 | thread_db_look_up_symbols (); |
0d62e5e8 | 740 | return 1; |
cdbfd419 | 741 | } |
0d62e5e8 | 742 | |
cdbfd419 PP |
743 | return 0; |
744 | } | |
745 | ||
ca5c370d PA |
746 | static int |
747 | any_thread_of (struct inferior_list_entry *entry, void *args) | |
748 | { | |
9a3c8263 | 749 | int *pid_p = (int *) args; |
ca5c370d PA |
750 | |
751 | if (ptid_get_pid (entry->id) == *pid_p) | |
752 | return 1; | |
753 | ||
754 | return 0; | |
755 | } | |
756 | ||
f9e39928 PA |
757 | static void |
758 | switch_to_process (struct process_info *proc) | |
759 | { | |
760 | int pid = pid_of (proc); | |
761 | ||
0bfdf32f | 762 | current_thread = |
f9e39928 PA |
763 | (struct thread_info *) find_inferior (&all_threads, |
764 | any_thread_of, &pid); | |
765 | } | |
766 | ||
cdbfd419 PP |
767 | /* Disconnect from libthread_db and free resources. */ |
768 | ||
8336d594 PA |
769 | static void |
770 | disable_thread_event_reporting (struct process_info *proc) | |
cdbfd419 | 771 | { |
fe978cb0 | 772 | struct thread_db *thread_db = proc->priv->thread_db; |
cdbfd419 PP |
773 | if (thread_db) |
774 | { | |
21e1bee4 PP |
775 | td_err_e (*td_ta_clear_event_p) (const td_thragent_t *ta, |
776 | td_thr_events_t *event); | |
777 | ||
fd7dd3e6 | 778 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
96e9210f PA |
779 | td_ta_clear_event_p |
780 | = (td_ta_clear_event_ftype *) dlsym (thread_db->handle, | |
781 | "td_ta_clear_event"); | |
fd7dd3e6 | 782 | #else |
fd7dd3e6 PA |
783 | td_ta_clear_event_p = &td_ta_clear_event; |
784 | #endif | |
785 | ||
8336d594 | 786 | if (td_ta_clear_event_p != NULL) |
21e1bee4 | 787 | { |
0bfdf32f | 788 | struct thread_info *saved_thread = current_thread; |
21e1bee4 | 789 | td_thr_events_t events; |
8336d594 | 790 | |
f9e39928 | 791 | switch_to_process (proc); |
21e1bee4 | 792 | |
fd7dd3e6 PA |
793 | /* Set the process wide mask saying we aren't interested |
794 | in any events anymore. */ | |
21e1bee4 PP |
795 | td_event_fillset (&events); |
796 | (*td_ta_clear_event_p) (thread_db->thread_agent, &events); | |
8336d594 | 797 | |
0bfdf32f | 798 | current_thread = saved_thread; |
21e1bee4 | 799 | } |
8336d594 PA |
800 | } |
801 | } | |
802 | ||
803 | void | |
804 | thread_db_detach (struct process_info *proc) | |
805 | { | |
fe978cb0 | 806 | struct thread_db *thread_db = proc->priv->thread_db; |
f9e39928 PA |
807 | |
808 | if (thread_db) | |
809 | { | |
810 | disable_thread_event_reporting (proc); | |
f9e39928 | 811 | } |
8336d594 PA |
812 | } |
813 | ||
814 | /* Disconnect from libthread_db and free resources. */ | |
815 | ||
816 | void | |
817 | thread_db_mourn (struct process_info *proc) | |
818 | { | |
fe978cb0 | 819 | struct thread_db *thread_db = proc->priv->thread_db; |
8336d594 PA |
820 | if (thread_db) |
821 | { | |
96e9210f | 822 | td_ta_delete_ftype *td_ta_delete_p; |
8336d594 PA |
823 | |
824 | #ifndef USE_LIBTHREAD_DB_DIRECTLY | |
96e9210f | 825 | td_ta_delete_p = (td_ta_delete_ftype *) dlsym (thread_db->handle, "td_ta_delete"); |
8336d594 PA |
826 | #else |
827 | td_ta_delete_p = &td_ta_delete; | |
828 | #endif | |
cdbfd419 | 829 | |
cdbfd419 PP |
830 | if (td_ta_delete_p != NULL) |
831 | (*td_ta_delete_p) (thread_db->thread_agent); | |
832 | ||
fd7dd3e6 | 833 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
cdbfd419 | 834 | dlclose (thread_db->handle); |
96f15937 PP |
835 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
836 | ||
cdbfd419 | 837 | free (thread_db); |
fe978cb0 | 838 | proc->priv->thread_db = NULL; |
cdbfd419 PP |
839 | } |
840 | } | |
841 | ||
842 | /* Handle "set libthread-db-search-path" monitor command and return 1. | |
843 | For any other command, return 0. */ | |
844 | ||
845 | int | |
846 | thread_db_handle_monitor_command (char *mon) | |
847 | { | |
84e578fb DE |
848 | const char *cmd = "set libthread-db-search-path"; |
849 | size_t cmd_len = strlen (cmd); | |
850 | ||
851 | if (strncmp (mon, cmd, cmd_len) == 0 | |
852 | && (mon[cmd_len] == '\0' | |
853 | || mon[cmd_len] == ' ')) | |
cdbfd419 | 854 | { |
84e578fb | 855 | const char *cp = mon + cmd_len; |
cdbfd419 PP |
856 | |
857 | if (libthread_db_search_path != NULL) | |
858 | free (libthread_db_search_path); | |
859 | ||
860 | /* Skip leading space (if any). */ | |
861 | while (isspace (*cp)) | |
862 | ++cp; | |
863 | ||
84e578fb DE |
864 | if (*cp == '\0') |
865 | cp = LIBTHREAD_DB_SEARCH_PATH; | |
cdbfd419 PP |
866 | libthread_db_search_path = xstrdup (cp); |
867 | ||
868 | monitor_output ("libthread-db-search-path set to `"); | |
869 | monitor_output (libthread_db_search_path); | |
870 | monitor_output ("'\n"); | |
871 | return 1; | |
0d62e5e8 DJ |
872 | } |
873 | ||
cdbfd419 | 874 | /* Tell server.c to perform default processing. */ |
0d62e5e8 DJ |
875 | return 0; |
876 | } |