| 1 | /* Thread management interface, for the remote server for GDB. |
| 2 | Copyright (C) 2002, 2004, 2005, 2006, 2007, 2008, 2009 |
| 3 | Free Software Foundation, Inc. |
| 4 | |
| 5 | Contributed by MontaVista Software. |
| 6 | |
| 7 | This file is part of GDB. |
| 8 | |
| 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 3 of the License, or |
| 12 | (at your option) any later version. |
| 13 | |
| 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. |
| 18 | |
| 19 | You should have received a copy of the GNU General Public License |
| 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 21 | |
| 22 | #include "server.h" |
| 23 | |
| 24 | #include "linux-low.h" |
| 25 | |
| 26 | extern int debug_threads; |
| 27 | |
| 28 | static int thread_db_use_events; |
| 29 | |
| 30 | #include "gdb_proc_service.h" |
| 31 | #include "../gdb_thread_db.h" |
| 32 | |
| 33 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
| 34 | #include <dlfcn.h> |
| 35 | #endif |
| 36 | |
| 37 | #include <stdint.h> |
| 38 | #include <limits.h> |
| 39 | #include <ctype.h> |
| 40 | |
| 41 | struct thread_db |
| 42 | { |
| 43 | /* Structure that identifies the child process for the |
| 44 | <proc_service.h> interface. */ |
| 45 | struct ps_prochandle proc_handle; |
| 46 | |
| 47 | /* Connection to the libthread_db library. */ |
| 48 | td_thragent_t *thread_agent; |
| 49 | |
| 50 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
| 51 | /* Handle of the libthread_db from dlopen. */ |
| 52 | void *handle; |
| 53 | #endif |
| 54 | |
| 55 | /* Addresses of libthread_db functions. */ |
| 56 | td_err_e (*td_ta_new_p) (struct ps_prochandle * ps, td_thragent_t **ta); |
| 57 | td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta, |
| 58 | td_event_msg_t *msg); |
| 59 | td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta, |
| 60 | td_thr_events_t *event); |
| 61 | td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta, |
| 62 | td_event_e event, td_notify_t *ptr); |
| 63 | td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta, lwpid_t lwpid, |
| 64 | td_thrhandle_t *th); |
| 65 | td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th, |
| 66 | td_thrinfo_t *infop); |
| 67 | td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th, int event); |
| 68 | td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta, |
| 69 | td_thr_iter_f *callback, void *cbdata_p, |
| 70 | td_thr_state_e state, int ti_pri, |
| 71 | sigset_t *ti_sigmask_p, |
| 72 | unsigned int ti_user_flags); |
| 73 | td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th, |
| 74 | psaddr_t map_address, |
| 75 | size_t offset, psaddr_t *address); |
| 76 | const char ** (*td_symbol_list_p) (void); |
| 77 | }; |
| 78 | |
| 79 | static char *libthread_db_search_path; |
| 80 | |
| 81 | static int find_one_thread (ptid_t); |
| 82 | static int find_new_threads_callback (const td_thrhandle_t *th_p, void *data); |
| 83 | |
| 84 | static const char * |
| 85 | thread_db_err_str (td_err_e err) |
| 86 | { |
| 87 | static char buf[64]; |
| 88 | |
| 89 | switch (err) |
| 90 | { |
| 91 | case TD_OK: |
| 92 | return "generic 'call succeeded'"; |
| 93 | case TD_ERR: |
| 94 | return "generic error"; |
| 95 | case TD_NOTHR: |
| 96 | return "no thread to satisfy query"; |
| 97 | case TD_NOSV: |
| 98 | return "no sync handle to satisfy query"; |
| 99 | case TD_NOLWP: |
| 100 | return "no LWP to satisfy query"; |
| 101 | case TD_BADPH: |
| 102 | return "invalid process handle"; |
| 103 | case TD_BADTH: |
| 104 | return "invalid thread handle"; |
| 105 | case TD_BADSH: |
| 106 | return "invalid synchronization handle"; |
| 107 | case TD_BADTA: |
| 108 | return "invalid thread agent"; |
| 109 | case TD_BADKEY: |
| 110 | return "invalid key"; |
| 111 | case TD_NOMSG: |
| 112 | return "no event message for getmsg"; |
| 113 | case TD_NOFPREGS: |
| 114 | return "FPU register set not available"; |
| 115 | case TD_NOLIBTHREAD: |
| 116 | return "application not linked with libthread"; |
| 117 | case TD_NOEVENT: |
| 118 | return "requested event is not supported"; |
| 119 | case TD_NOCAPAB: |
| 120 | return "capability not available"; |
| 121 | case TD_DBERR: |
| 122 | return "debugger service failed"; |
| 123 | case TD_NOAPLIC: |
| 124 | return "operation not applicable to"; |
| 125 | case TD_NOTSD: |
| 126 | return "no thread-specific data for this thread"; |
| 127 | case TD_MALLOC: |
| 128 | return "malloc failed"; |
| 129 | case TD_PARTIALREG: |
| 130 | return "only part of register set was written/read"; |
| 131 | case TD_NOXREGS: |
| 132 | return "X register set not available for this thread"; |
| 133 | #ifdef HAVE_TD_VERSION |
| 134 | case TD_VERSION: |
| 135 | return "version mismatch between libthread_db and libpthread"; |
| 136 | #endif |
| 137 | default: |
| 138 | snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
| 139 | return buf; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | #if 0 |
| 144 | static char * |
| 145 | thread_db_state_str (td_thr_state_e state) |
| 146 | { |
| 147 | static char buf[64]; |
| 148 | |
| 149 | switch (state) |
| 150 | { |
| 151 | case TD_THR_STOPPED: |
| 152 | return "stopped by debugger"; |
| 153 | case TD_THR_RUN: |
| 154 | return "runnable"; |
| 155 | case TD_THR_ACTIVE: |
| 156 | return "active"; |
| 157 | case TD_THR_ZOMBIE: |
| 158 | return "zombie"; |
| 159 | case TD_THR_SLEEP: |
| 160 | return "sleeping"; |
| 161 | case TD_THR_STOPPED_ASLEEP: |
| 162 | return "stopped by debugger AND blocked"; |
| 163 | default: |
| 164 | snprintf (buf, sizeof (buf), "unknown thread_db state %d", state); |
| 165 | return buf; |
| 166 | } |
| 167 | } |
| 168 | #endif |
| 169 | |
| 170 | static int |
| 171 | thread_db_create_event (CORE_ADDR where) |
| 172 | { |
| 173 | td_event_msg_t msg; |
| 174 | td_err_e err; |
| 175 | struct lwp_info *lwp; |
| 176 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 177 | |
| 178 | if (thread_db->td_ta_event_getmsg_p == NULL) |
| 179 | fatal ("unexpected thread_db->td_ta_event_getmsg_p == NULL"); |
| 180 | |
| 181 | if (debug_threads) |
| 182 | fprintf (stderr, "Thread creation event.\n"); |
| 183 | |
| 184 | /* FIXME: This assumes we don't get another event. |
| 185 | In the LinuxThreads implementation, this is safe, |
| 186 | because all events come from the manager thread |
| 187 | (except for its own creation, of course). */ |
| 188 | err = thread_db->td_ta_event_getmsg_p (thread_db->thread_agent, &msg); |
| 189 | if (err != TD_OK) |
| 190 | fprintf (stderr, "thread getmsg err: %s\n", |
| 191 | thread_db_err_str (err)); |
| 192 | |
| 193 | /* If we do not know about the main thread yet, this would be a good time to |
| 194 | find it. We need to do this to pick up the main thread before any newly |
| 195 | created threads. */ |
| 196 | lwp = get_thread_lwp (current_inferior); |
| 197 | if (lwp->thread_known == 0) |
| 198 | find_one_thread (lwp->head.id); |
| 199 | |
| 200 | /* msg.event == TD_EVENT_CREATE */ |
| 201 | |
| 202 | find_new_threads_callback (msg.th_p, NULL); |
| 203 | |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | static int |
| 208 | thread_db_enable_reporting () |
| 209 | { |
| 210 | td_thr_events_t events; |
| 211 | td_notify_t notify; |
| 212 | td_err_e err; |
| 213 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 214 | |
| 215 | if (thread_db->td_ta_set_event_p == NULL |
| 216 | || thread_db->td_ta_event_addr_p == NULL |
| 217 | || thread_db->td_ta_event_getmsg_p == NULL) |
| 218 | /* This libthread_db is missing required support. */ |
| 219 | return 0; |
| 220 | |
| 221 | /* Set the process wide mask saying which events we're interested in. */ |
| 222 | td_event_emptyset (&events); |
| 223 | td_event_addset (&events, TD_CREATE); |
| 224 | |
| 225 | err = thread_db->td_ta_set_event_p (thread_db->thread_agent, &events); |
| 226 | if (err != TD_OK) |
| 227 | { |
| 228 | warning ("Unable to set global thread event mask: %s", |
| 229 | thread_db_err_str (err)); |
| 230 | return 0; |
| 231 | } |
| 232 | |
| 233 | /* Get address for thread creation breakpoint. */ |
| 234 | err = thread_db->td_ta_event_addr_p (thread_db->thread_agent, TD_CREATE, |
| 235 | ¬ify); |
| 236 | if (err != TD_OK) |
| 237 | { |
| 238 | warning ("Unable to get location for thread creation breakpoint: %s", |
| 239 | thread_db_err_str (err)); |
| 240 | return 0; |
| 241 | } |
| 242 | set_breakpoint_at ((CORE_ADDR) (unsigned long) notify.u.bptaddr, |
| 243 | thread_db_create_event); |
| 244 | |
| 245 | return 1; |
| 246 | } |
| 247 | |
| 248 | static int |
| 249 | find_one_thread (ptid_t ptid) |
| 250 | { |
| 251 | td_thrhandle_t th; |
| 252 | td_thrinfo_t ti; |
| 253 | td_err_e err; |
| 254 | struct thread_info *inferior; |
| 255 | struct lwp_info *lwp; |
| 256 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 257 | int lwpid = ptid_get_lwp (ptid); |
| 258 | |
| 259 | inferior = (struct thread_info *) find_inferior_id (&all_threads, ptid); |
| 260 | lwp = get_thread_lwp (inferior); |
| 261 | if (lwp->thread_known) |
| 262 | return 1; |
| 263 | |
| 264 | /* Get information about this thread. */ |
| 265 | err = thread_db->td_ta_map_lwp2thr_p (thread_db->thread_agent, lwpid, &th); |
| 266 | if (err != TD_OK) |
| 267 | error ("Cannot get thread handle for LWP %d: %s", |
| 268 | lwpid, thread_db_err_str (err)); |
| 269 | |
| 270 | err = thread_db->td_thr_get_info_p (&th, &ti); |
| 271 | if (err != TD_OK) |
| 272 | error ("Cannot get thread info for LWP %d: %s", |
| 273 | lwpid, thread_db_err_str (err)); |
| 274 | |
| 275 | if (debug_threads) |
| 276 | fprintf (stderr, "Found thread %ld (LWP %d)\n", |
| 277 | ti.ti_tid, ti.ti_lid); |
| 278 | |
| 279 | if (lwpid != ti.ti_lid) |
| 280 | { |
| 281 | warning ("PID mismatch! Expected %ld, got %ld", |
| 282 | (long) lwpid, (long) ti.ti_lid); |
| 283 | return 0; |
| 284 | } |
| 285 | |
| 286 | if (thread_db_use_events) |
| 287 | { |
| 288 | err = thread_db->td_thr_event_enable_p (&th, 1); |
| 289 | if (err != TD_OK) |
| 290 | error ("Cannot enable thread event reporting for %d: %s", |
| 291 | ti.ti_lid, thread_db_err_str (err)); |
| 292 | } |
| 293 | |
| 294 | /* If the new thread ID is zero, a final thread ID will be available |
| 295 | later. Do not enable thread debugging yet. */ |
| 296 | if (ti.ti_tid == 0) |
| 297 | return 0; |
| 298 | |
| 299 | lwp->thread_known = 1; |
| 300 | lwp->th = th; |
| 301 | |
| 302 | return 1; |
| 303 | } |
| 304 | |
| 305 | /* Attach a thread. Return true on success. */ |
| 306 | |
| 307 | static int |
| 308 | attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p) |
| 309 | { |
| 310 | struct lwp_info *lwp; |
| 311 | |
| 312 | if (debug_threads) |
| 313 | fprintf (stderr, "Attaching to thread %ld (LWP %d)\n", |
| 314 | ti_p->ti_tid, ti_p->ti_lid); |
| 315 | linux_attach_lwp (ti_p->ti_lid); |
| 316 | lwp = find_lwp_pid (pid_to_ptid (ti_p->ti_lid)); |
| 317 | if (lwp == NULL) |
| 318 | { |
| 319 | warning ("Could not attach to thread %ld (LWP %d)\n", |
| 320 | ti_p->ti_tid, ti_p->ti_lid); |
| 321 | return 0; |
| 322 | } |
| 323 | |
| 324 | lwp->thread_known = 1; |
| 325 | lwp->th = *th_p; |
| 326 | |
| 327 | if (thread_db_use_events) |
| 328 | { |
| 329 | td_err_e err; |
| 330 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 331 | |
| 332 | err = thread_db->td_thr_event_enable_p (th_p, 1); |
| 333 | if (err != TD_OK) |
| 334 | error ("Cannot enable thread event reporting for %d: %s", |
| 335 | ti_p->ti_lid, thread_db_err_str (err)); |
| 336 | } |
| 337 | |
| 338 | return 1; |
| 339 | } |
| 340 | |
| 341 | /* Attach thread if we haven't seen it yet. |
| 342 | Increment *COUNTER if we have attached a new thread. |
| 343 | Return false on failure. */ |
| 344 | |
| 345 | static int |
| 346 | maybe_attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p, |
| 347 | int *counter) |
| 348 | { |
| 349 | struct lwp_info *lwp; |
| 350 | |
| 351 | lwp = find_lwp_pid (pid_to_ptid (ti_p->ti_lid)); |
| 352 | if (lwp != NULL) |
| 353 | return 1; |
| 354 | |
| 355 | if (!attach_thread (th_p, ti_p)) |
| 356 | return 0; |
| 357 | |
| 358 | if (counter != NULL) |
| 359 | *counter += 1; |
| 360 | |
| 361 | return 1; |
| 362 | } |
| 363 | |
| 364 | static int |
| 365 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) |
| 366 | { |
| 367 | td_thrinfo_t ti; |
| 368 | td_err_e err; |
| 369 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 370 | |
| 371 | err = thread_db->td_thr_get_info_p (th_p, &ti); |
| 372 | if (err != TD_OK) |
| 373 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 374 | |
| 375 | /* Check for zombies. */ |
| 376 | if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE) |
| 377 | return 0; |
| 378 | |
| 379 | if (!maybe_attach_thread (th_p, &ti, (int *) data)) |
| 380 | { |
| 381 | /* Terminate iteration early: we might be looking at stale data in |
| 382 | the inferior. The thread_db_find_new_threads will retry. */ |
| 383 | return 1; |
| 384 | } |
| 385 | |
| 386 | return 0; |
| 387 | } |
| 388 | |
| 389 | static void |
| 390 | thread_db_find_new_threads (void) |
| 391 | { |
| 392 | td_err_e err; |
| 393 | ptid_t ptid = ((struct inferior_list_entry *) current_inferior)->id; |
| 394 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 395 | int loop, iteration; |
| 396 | |
| 397 | /* This function is only called when we first initialize thread_db. |
| 398 | First locate the initial thread. If it is not ready for |
| 399 | debugging yet, then stop. */ |
| 400 | if (find_one_thread (ptid) == 0) |
| 401 | return; |
| 402 | |
| 403 | /* Require 4 successive iterations which do not find any new threads. |
| 404 | The 4 is a heuristic: there is an inherent race here, and I have |
| 405 | seen that 2 iterations in a row are not always sufficient to |
| 406 | "capture" all threads. */ |
| 407 | for (loop = 0, iteration = 0; loop < 4; ++loop, ++iteration) |
| 408 | { |
| 409 | int new_thread_count = 0; |
| 410 | |
| 411 | /* Iterate over all user-space threads to discover new threads. */ |
| 412 | err = thread_db->td_ta_thr_iter_p (thread_db->thread_agent, |
| 413 | find_new_threads_callback, |
| 414 | &new_thread_count, |
| 415 | TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY, |
| 416 | TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS); |
| 417 | if (debug_threads) |
| 418 | fprintf (stderr, "Found %d threads in iteration %d.\n", |
| 419 | new_thread_count, iteration); |
| 420 | |
| 421 | if (new_thread_count != 0) |
| 422 | { |
| 423 | /* Found new threads. Restart iteration from beginning. */ |
| 424 | loop = -1; |
| 425 | } |
| 426 | } |
| 427 | if (err != TD_OK) |
| 428 | error ("Cannot find new threads: %s", thread_db_err_str (err)); |
| 429 | } |
| 430 | |
| 431 | /* Cache all future symbols that thread_db might request. We can not |
| 432 | request symbols at arbitrary states in the remote protocol, only |
| 433 | when the client tells us that new symbols are available. So when |
| 434 | we load the thread library, make sure to check the entire list. */ |
| 435 | |
| 436 | static void |
| 437 | thread_db_look_up_symbols (void) |
| 438 | { |
| 439 | struct thread_db *thread_db = current_process ()->private->thread_db; |
| 440 | const char **sym_list; |
| 441 | CORE_ADDR unused; |
| 442 | |
| 443 | for (sym_list = thread_db->td_symbol_list_p (); *sym_list; sym_list++) |
| 444 | look_up_one_symbol (*sym_list, &unused); |
| 445 | } |
| 446 | |
| 447 | int |
| 448 | thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset, |
| 449 | CORE_ADDR load_module, CORE_ADDR *address) |
| 450 | { |
| 451 | psaddr_t addr; |
| 452 | td_err_e err; |
| 453 | struct lwp_info *lwp; |
| 454 | struct thread_info *saved_inferior; |
| 455 | struct process_info *proc; |
| 456 | struct thread_db *thread_db; |
| 457 | |
| 458 | proc = get_thread_process (thread); |
| 459 | thread_db = proc->private->thread_db; |
| 460 | |
| 461 | /* If the thread layer is not (yet) initialized, fail. */ |
| 462 | if (!proc->all_symbols_looked_up) |
| 463 | return TD_ERR; |
| 464 | |
| 465 | if (thread_db->td_thr_tls_get_addr_p == NULL) |
| 466 | return -1; |
| 467 | |
| 468 | lwp = get_thread_lwp (thread); |
| 469 | if (!lwp->thread_known) |
| 470 | find_one_thread (lwp->head.id); |
| 471 | if (!lwp->thread_known) |
| 472 | return TD_NOTHR; |
| 473 | |
| 474 | saved_inferior = current_inferior; |
| 475 | current_inferior = thread; |
| 476 | /* Note the cast through uintptr_t: this interface only works if |
| 477 | a target address fits in a psaddr_t, which is a host pointer. |
| 478 | So a 32-bit debugger can not access 64-bit TLS through this. */ |
| 479 | err = thread_db->td_thr_tls_get_addr_p (&lwp->th, |
| 480 | (psaddr_t) (uintptr_t) load_module, |
| 481 | offset, &addr); |
| 482 | current_inferior = saved_inferior; |
| 483 | if (err == TD_OK) |
| 484 | { |
| 485 | *address = (CORE_ADDR) (uintptr_t) addr; |
| 486 | return 0; |
| 487 | } |
| 488 | else |
| 489 | return err; |
| 490 | } |
| 491 | |
| 492 | #ifdef USE_LIBTHREAD_DB_DIRECTLY |
| 493 | |
| 494 | static int |
| 495 | thread_db_load_search (void) |
| 496 | { |
| 497 | td_err_e err; |
| 498 | struct thread_db tdb; |
| 499 | struct process_info *proc = current_process (); |
| 500 | |
| 501 | if (proc->private->thread_db != NULL) |
| 502 | fatal ("unexpected: proc->private->thread_db != NULL"); |
| 503 | |
| 504 | tdb.td_ta_new_p = &td_ta_new; |
| 505 | |
| 506 | /* Attempt to open a connection to the thread library. */ |
| 507 | err = tdb.td_ta_new_p (&tdb.proc_handle, &tdb.thread_agent); |
| 508 | if (err != TD_OK) |
| 509 | { |
| 510 | if (debug_threads) |
| 511 | fprintf (stderr, "td_ta_new(): %s\n", thread_db_err_str (err)); |
| 512 | return 0; |
| 513 | } |
| 514 | |
| 515 | tdb.td_ta_map_lwp2thr_p = &td_ta_map_lwp2thr; |
| 516 | tdb.td_thr_get_info_p = &td_thr_get_info; |
| 517 | tdb.td_ta_thr_iter_p = &td_ta_thr_iter; |
| 518 | tdb.td_symbol_list_p = &td_symbol_list; |
| 519 | |
| 520 | /* This is required only when thread_db_use_events is on. */ |
| 521 | tdb.td_thr_event_enable_p = &td_thr_event_enable; |
| 522 | |
| 523 | /* These are not essential. */ |
| 524 | tdb.td_ta_event_addr_p = &td_ta_event_addr; |
| 525 | tdb.td_ta_set_event_p = &td_ta_set_event; |
| 526 | tdb.td_ta_event_getmsg_p = &td_ta_event_getmsg; |
| 527 | tdb.td_thr_tls_get_addr_p = &td_thr_tls_get_addr; |
| 528 | |
| 529 | proc->private->thread_db = xmalloc (sizeof (tdb)); |
| 530 | memcpy (proc->private->thread_db, &tdb, sizeof (tdb)); |
| 531 | |
| 532 | return 1; |
| 533 | } |
| 534 | |
| 535 | #else |
| 536 | |
| 537 | static int |
| 538 | try_thread_db_load_1 (void *handle) |
| 539 | { |
| 540 | td_err_e err; |
| 541 | struct thread_db tdb; |
| 542 | struct process_info *proc = current_process (); |
| 543 | |
| 544 | if (proc->private->thread_db != NULL) |
| 545 | fatal ("unexpected: proc->private->thread_db != NULL"); |
| 546 | |
| 547 | tdb.handle = handle; |
| 548 | |
| 549 | /* Initialize pointers to the dynamic library functions we will use. |
| 550 | Essential functions first. */ |
| 551 | |
| 552 | #define CHK(required, a) \ |
| 553 | do \ |
| 554 | { \ |
| 555 | if ((a) == NULL) \ |
| 556 | { \ |
| 557 | if (debug_threads) \ |
| 558 | fprintf (stderr, "dlsym: %s\n", dlerror ()); \ |
| 559 | if (required) \ |
| 560 | return 0; \ |
| 561 | } \ |
| 562 | } \ |
| 563 | while (0) |
| 564 | |
| 565 | CHK (1, tdb.td_ta_new_p = dlsym (handle, "td_ta_new")); |
| 566 | |
| 567 | /* Attempt to open a connection to the thread library. */ |
| 568 | err = tdb.td_ta_new_p (&tdb.proc_handle, &tdb.thread_agent); |
| 569 | if (err != TD_OK) |
| 570 | { |
| 571 | if (debug_threads) |
| 572 | fprintf (stderr, "td_ta_new(): %s\n", thread_db_err_str (err)); |
| 573 | return 0; |
| 574 | } |
| 575 | |
| 576 | CHK (1, tdb.td_ta_map_lwp2thr_p = dlsym (handle, "td_ta_map_lwp2thr")); |
| 577 | CHK (1, tdb.td_thr_get_info_p = dlsym (handle, "td_thr_get_info")); |
| 578 | CHK (1, tdb.td_ta_thr_iter_p = dlsym (handle, "td_ta_thr_iter")); |
| 579 | CHK (1, tdb.td_symbol_list_p = dlsym (handle, "td_symbol_list")); |
| 580 | |
| 581 | /* This is required only when thread_db_use_events is on. */ |
| 582 | CHK (thread_db_use_events, |
| 583 | tdb.td_thr_event_enable_p = dlsym (handle, "td_thr_event_enable")); |
| 584 | |
| 585 | /* These are not essential. */ |
| 586 | CHK (0, tdb.td_ta_event_addr_p = dlsym (handle, "td_ta_event_addr")); |
| 587 | CHK (0, tdb.td_ta_set_event_p = dlsym (handle, "td_ta_set_event")); |
| 588 | CHK (0, tdb.td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg")); |
| 589 | CHK (0, tdb.td_thr_tls_get_addr_p = dlsym (handle, "td_thr_tls_get_addr")); |
| 590 | |
| 591 | #undef CHK |
| 592 | |
| 593 | proc->private->thread_db = xmalloc (sizeof (tdb)); |
| 594 | memcpy (proc->private->thread_db, &tdb, sizeof (tdb)); |
| 595 | |
| 596 | return 1; |
| 597 | } |
| 598 | |
| 599 | /* Lookup a library in which given symbol resides. |
| 600 | Note: this is looking in the GDBSERVER process, not in the inferior. |
| 601 | Returns library name, or NULL. */ |
| 602 | |
| 603 | static const char * |
| 604 | dladdr_to_soname (const void *addr) |
| 605 | { |
| 606 | Dl_info info; |
| 607 | |
| 608 | if (dladdr (addr, &info) != 0) |
| 609 | return info.dli_fname; |
| 610 | return NULL; |
| 611 | } |
| 612 | |
| 613 | static int |
| 614 | try_thread_db_load (const char *library) |
| 615 | { |
| 616 | void *handle; |
| 617 | |
| 618 | if (debug_threads) |
| 619 | fprintf (stderr, "Trying host libthread_db library: %s.\n", |
| 620 | library); |
| 621 | handle = dlopen (library, RTLD_NOW); |
| 622 | if (handle == NULL) |
| 623 | { |
| 624 | if (debug_threads) |
| 625 | fprintf (stderr, "dlopen failed: %s.\n", dlerror ()); |
| 626 | return 0; |
| 627 | } |
| 628 | |
| 629 | if (debug_threads && strchr (library, '/') == NULL) |
| 630 | { |
| 631 | void *td_init; |
| 632 | |
| 633 | td_init = dlsym (handle, "td_init"); |
| 634 | if (td_init != NULL) |
| 635 | { |
| 636 | const char *const libpath = dladdr_to_soname (td_init); |
| 637 | |
| 638 | if (libpath != NULL) |
| 639 | fprintf (stderr, "Host %s resolved to: %s.\n", |
| 640 | library, libpath); |
| 641 | } |
| 642 | } |
| 643 | |
| 644 | if (try_thread_db_load_1 (handle)) |
| 645 | return 1; |
| 646 | |
| 647 | /* This library "refused" to work on current inferior. */ |
| 648 | dlclose (handle); |
| 649 | return 0; |
| 650 | } |
| 651 | |
| 652 | static int |
| 653 | thread_db_load_search (void) |
| 654 | { |
| 655 | char path[PATH_MAX]; |
| 656 | const char *search_path; |
| 657 | int rc = 0; |
| 658 | |
| 659 | if (libthread_db_search_path == NULL) |
| 660 | libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH); |
| 661 | |
| 662 | search_path = libthread_db_search_path; |
| 663 | while (*search_path) |
| 664 | { |
| 665 | const char *end = strchr (search_path, ':'); |
| 666 | if (end) |
| 667 | { |
| 668 | size_t len = end - search_path; |
| 669 | if (len + 1 + strlen (LIBTHREAD_DB_SO) + 1 > sizeof (path)) |
| 670 | { |
| 671 | char *cp = xmalloc (len + 1); |
| 672 | memcpy (cp, search_path, len); |
| 673 | cp[len] = '\0'; |
| 674 | warning ("libthread_db_search_path component too long, " |
| 675 | "ignored: %s.", cp); |
| 676 | free (cp); |
| 677 | search_path += len + 1; |
| 678 | continue; |
| 679 | } |
| 680 | memcpy (path, search_path, len); |
| 681 | path[len] = '\0'; |
| 682 | search_path += len + 1; |
| 683 | } |
| 684 | else |
| 685 | { |
| 686 | size_t len = strlen (search_path); |
| 687 | |
| 688 | if (len + 1 + strlen (LIBTHREAD_DB_SO) + 1 > sizeof (path)) |
| 689 | { |
| 690 | warning ("libthread_db_search_path component too long," |
| 691 | " ignored: %s.", search_path); |
| 692 | break; |
| 693 | } |
| 694 | memcpy (path, search_path, len + 1); |
| 695 | search_path += len; |
| 696 | } |
| 697 | strcat (path, "/"); |
| 698 | strcat (path, LIBTHREAD_DB_SO); |
| 699 | if (debug_threads) |
| 700 | fprintf (stderr, "thread_db_load_search trying %s\n", path); |
| 701 | if (try_thread_db_load (path)) |
| 702 | { |
| 703 | rc = 1; |
| 704 | break; |
| 705 | } |
| 706 | } |
| 707 | if (rc == 0) |
| 708 | rc = try_thread_db_load (LIBTHREAD_DB_SO); |
| 709 | |
| 710 | if (debug_threads) |
| 711 | fprintf (stderr, "thread_db_load_search returning %d\n", rc); |
| 712 | return rc; |
| 713 | } |
| 714 | |
| 715 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
| 716 | |
| 717 | int |
| 718 | thread_db_init (int use_events) |
| 719 | { |
| 720 | struct process_info *proc = current_process (); |
| 721 | |
| 722 | /* FIXME drow/2004-10-16: This is the "overall process ID", which |
| 723 | GNU/Linux calls tgid, "thread group ID". When we support |
| 724 | attaching to threads, the original thread may not be the correct |
| 725 | thread. We would have to get the process ID from /proc for NPTL. |
| 726 | For LinuxThreads we could do something similar: follow the chain |
| 727 | of parent processes until we find the highest one we're attached |
| 728 | to, and use its tgid. |
| 729 | |
| 730 | This isn't the only place in gdbserver that assumes that the first |
| 731 | process in the list is the thread group leader. */ |
| 732 | |
| 733 | thread_db_use_events = use_events; |
| 734 | |
| 735 | if (thread_db_load_search ()) |
| 736 | { |
| 737 | if (use_events && thread_db_enable_reporting () == 0) |
| 738 | { |
| 739 | /* Keep trying; maybe event reporting will work later. */ |
| 740 | thread_db_free (proc, 0); |
| 741 | return 0; |
| 742 | } |
| 743 | thread_db_find_new_threads (); |
| 744 | thread_db_look_up_symbols (); |
| 745 | proc->all_symbols_looked_up = 1; |
| 746 | return 1; |
| 747 | } |
| 748 | |
| 749 | return 0; |
| 750 | } |
| 751 | |
| 752 | /* Disconnect from libthread_db and free resources. */ |
| 753 | |
| 754 | void |
| 755 | thread_db_free (struct process_info *proc, int detaching) |
| 756 | { |
| 757 | struct thread_db *thread_db = proc->private->thread_db; |
| 758 | if (thread_db) |
| 759 | { |
| 760 | td_err_e (*td_ta_delete_p) (td_thragent_t *); |
| 761 | td_err_e (*td_ta_clear_event_p) (const td_thragent_t *ta, |
| 762 | td_thr_events_t *event); |
| 763 | |
| 764 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
| 765 | td_ta_clear_event_p = dlsym (thread_db->handle, "td_ta_clear_event"); |
| 766 | td_ta_delete_p = dlsym (thread_db->handle, "td_ta_delete"); |
| 767 | #else |
| 768 | td_ta_delete_p = &td_ta_delete; |
| 769 | td_ta_clear_event_p = &td_ta_clear_event; |
| 770 | #endif |
| 771 | |
| 772 | if (detaching && td_ta_clear_event_p != NULL) |
| 773 | { |
| 774 | td_thr_events_t events; |
| 775 | |
| 776 | /* Set the process wide mask saying we aren't interested |
| 777 | in any events anymore. */ |
| 778 | td_event_fillset (&events); |
| 779 | (*td_ta_clear_event_p) (thread_db->thread_agent, &events); |
| 780 | } |
| 781 | |
| 782 | if (td_ta_delete_p != NULL) |
| 783 | (*td_ta_delete_p) (thread_db->thread_agent); |
| 784 | |
| 785 | #ifndef USE_LIBTHREAD_DB_DIRECTLY |
| 786 | dlclose (thread_db->handle); |
| 787 | #endif /* USE_LIBTHREAD_DB_DIRECTLY */ |
| 788 | |
| 789 | free (thread_db); |
| 790 | proc->private->thread_db = NULL; |
| 791 | } |
| 792 | } |
| 793 | |
| 794 | /* Handle "set libthread-db-search-path" monitor command and return 1. |
| 795 | For any other command, return 0. */ |
| 796 | |
| 797 | int |
| 798 | thread_db_handle_monitor_command (char *mon) |
| 799 | { |
| 800 | if (strncmp (mon, "set libthread-db-search-path ", 29) == 0) |
| 801 | { |
| 802 | const char *cp = mon + 29; |
| 803 | |
| 804 | if (libthread_db_search_path != NULL) |
| 805 | free (libthread_db_search_path); |
| 806 | |
| 807 | /* Skip leading space (if any). */ |
| 808 | while (isspace (*cp)) |
| 809 | ++cp; |
| 810 | |
| 811 | libthread_db_search_path = xstrdup (cp); |
| 812 | |
| 813 | monitor_output ("libthread-db-search-path set to `"); |
| 814 | monitor_output (libthread_db_search_path); |
| 815 | monitor_output ("'\n"); |
| 816 | return 1; |
| 817 | } |
| 818 | |
| 819 | /* Tell server.c to perform default processing. */ |
| 820 | return 0; |
| 821 | } |