| 1 | /* libthread_db assisted debugging support, generic parts. |
| 2 | |
| 3 | Copyright (C) 1999-2016 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include <dlfcn.h> |
| 22 | #include "gdb_proc_service.h" |
| 23 | #include "nat/gdb_thread_db.h" |
| 24 | #include "gdb_vecs.h" |
| 25 | #include "bfd.h" |
| 26 | #include "command.h" |
| 27 | #include "gdbcmd.h" |
| 28 | #include "gdbthread.h" |
| 29 | #include "inferior.h" |
| 30 | #include "infrun.h" |
| 31 | #include "symfile.h" |
| 32 | #include "objfiles.h" |
| 33 | #include "target.h" |
| 34 | #include "regcache.h" |
| 35 | #include "solib.h" |
| 36 | #include "solib-svr4.h" |
| 37 | #include "gdbcore.h" |
| 38 | #include "observer.h" |
| 39 | #include "linux-nat.h" |
| 40 | #include "nat/linux-procfs.h" |
| 41 | #include "nat/linux-ptrace.h" |
| 42 | #include "nat/linux-osdata.h" |
| 43 | #include "auto-load.h" |
| 44 | #include "cli/cli-utils.h" |
| 45 | #include <signal.h> |
| 46 | #include <ctype.h> |
| 47 | #include "nat/linux-namespaces.h" |
| 48 | |
| 49 | /* GNU/Linux libthread_db support. |
| 50 | |
| 51 | libthread_db is a library, provided along with libpthread.so, which |
| 52 | exposes the internals of the thread library to a debugger. It |
| 53 | allows GDB to find existing threads, new threads as they are |
| 54 | created, thread IDs (usually, the result of pthread_self), and |
| 55 | thread-local variables. |
| 56 | |
| 57 | The libthread_db interface originates on Solaris, where it is both |
| 58 | more powerful and more complicated. This implementation only works |
| 59 | for NPTL, the glibc threading library. It assumes that each thread |
| 60 | is permanently assigned to a single light-weight process (LWP). At |
| 61 | some point it also supported the older LinuxThreads library, but it |
| 62 | no longer does. |
| 63 | |
| 64 | libthread_db-specific information is stored in the "private" field |
| 65 | of struct thread_info. When the field is NULL we do not yet have |
| 66 | information about the new thread; this could be temporary (created, |
| 67 | but the thread library's data structures do not reflect it yet) |
| 68 | or permanent (created using clone instead of pthread_create). |
| 69 | |
| 70 | Process IDs managed by linux-thread-db.c match those used by |
| 71 | linux-nat.c: a common PID for all processes, an LWP ID for each |
| 72 | thread, and no TID. We save the TID in private. Keeping it out |
| 73 | of the ptid_t prevents thread IDs changing when libpthread is |
| 74 | loaded or unloaded. */ |
| 75 | |
| 76 | static char *libthread_db_search_path; |
| 77 | |
| 78 | /* Set to non-zero if thread_db auto-loading is enabled |
| 79 | by the "set auto-load libthread-db" command. */ |
| 80 | static int auto_load_thread_db = 1; |
| 81 | |
| 82 | /* "show" command for the auto_load_thread_db configuration variable. */ |
| 83 | |
| 84 | static void |
| 85 | show_auto_load_thread_db (struct ui_file *file, int from_tty, |
| 86 | struct cmd_list_element *c, const char *value) |
| 87 | { |
| 88 | fprintf_filtered (file, _("Auto-loading of inferior specific libthread_db " |
| 89 | "is %s.\n"), |
| 90 | value); |
| 91 | } |
| 92 | |
| 93 | static void |
| 94 | set_libthread_db_search_path (char *ignored, int from_tty, |
| 95 | struct cmd_list_element *c) |
| 96 | { |
| 97 | if (*libthread_db_search_path == '\0') |
| 98 | { |
| 99 | xfree (libthread_db_search_path); |
| 100 | libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH); |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | /* If non-zero, print details of libthread_db processing. */ |
| 105 | |
| 106 | static unsigned int libthread_db_debug; |
| 107 | |
| 108 | static void |
| 109 | show_libthread_db_debug (struct ui_file *file, int from_tty, |
| 110 | struct cmd_list_element *c, const char *value) |
| 111 | { |
| 112 | fprintf_filtered (file, _("libthread-db debugging is %s.\n"), value); |
| 113 | } |
| 114 | |
| 115 | /* If we're running on GNU/Linux, we must explicitly attach to any new |
| 116 | threads. */ |
| 117 | |
| 118 | /* This module's target vector. */ |
| 119 | static struct target_ops thread_db_ops; |
| 120 | |
| 121 | /* Non-zero if we have determined the signals used by the threads |
| 122 | library. */ |
| 123 | static int thread_signals; |
| 124 | static sigset_t thread_stop_set; |
| 125 | static sigset_t thread_print_set; |
| 126 | |
| 127 | struct thread_db_info |
| 128 | { |
| 129 | struct thread_db_info *next; |
| 130 | |
| 131 | /* Process id this object refers to. */ |
| 132 | int pid; |
| 133 | |
| 134 | /* Handle from dlopen for libthread_db.so. */ |
| 135 | void *handle; |
| 136 | |
| 137 | /* Absolute pathname from gdb_realpath to disk file used for dlopen-ing |
| 138 | HANDLE. It may be NULL for system library. */ |
| 139 | char *filename; |
| 140 | |
| 141 | /* Structure that identifies the child process for the |
| 142 | <proc_service.h> interface. */ |
| 143 | struct ps_prochandle proc_handle; |
| 144 | |
| 145 | /* Connection to the libthread_db library. */ |
| 146 | td_thragent_t *thread_agent; |
| 147 | |
| 148 | /* True if we need to apply the workaround for glibc/BZ5983. When |
| 149 | we catch a PTRACE_O_TRACEFORK, and go query the child's thread |
| 150 | list, nptl_db returns the parent's threads in addition to the new |
| 151 | (single) child thread. If this flag is set, we do extra work to |
| 152 | be able to ignore such stale entries. */ |
| 153 | int need_stale_parent_threads_check; |
| 154 | |
| 155 | /* Pointers to the libthread_db functions. */ |
| 156 | |
| 157 | td_init_ftype *td_init_p; |
| 158 | td_ta_new_ftype *td_ta_new_p; |
| 159 | td_ta_map_lwp2thr_ftype *td_ta_map_lwp2thr_p; |
| 160 | td_ta_thr_iter_ftype *td_ta_thr_iter_p; |
| 161 | td_thr_validate_ftype *td_thr_validate_p; |
| 162 | td_thr_get_info_ftype *td_thr_get_info_p; |
| 163 | td_thr_tls_get_addr_ftype *td_thr_tls_get_addr_p; |
| 164 | td_thr_tlsbase_ftype *td_thr_tlsbase_p; |
| 165 | }; |
| 166 | |
| 167 | /* List of known processes using thread_db, and the required |
| 168 | bookkeeping. */ |
| 169 | struct thread_db_info *thread_db_list; |
| 170 | |
| 171 | static void thread_db_find_new_threads_1 (ptid_t ptid); |
| 172 | static void thread_db_find_new_threads_2 (ptid_t ptid, int until_no_new); |
| 173 | |
| 174 | static void check_thread_signals (void); |
| 175 | |
| 176 | static struct thread_info *record_thread |
| 177 | (struct thread_db_info *info, struct thread_info *tp, |
| 178 | ptid_t ptid, const td_thrhandle_t *th_p, const td_thrinfo_t *ti_p); |
| 179 | |
| 180 | /* Add the current inferior to the list of processes using libpthread. |
| 181 | Return a pointer to the newly allocated object that was added to |
| 182 | THREAD_DB_LIST. HANDLE is the handle returned by dlopen'ing |
| 183 | LIBTHREAD_DB_SO. */ |
| 184 | |
| 185 | static struct thread_db_info * |
| 186 | add_thread_db_info (void *handle) |
| 187 | { |
| 188 | struct thread_db_info *info = XCNEW (struct thread_db_info); |
| 189 | |
| 190 | info->pid = ptid_get_pid (inferior_ptid); |
| 191 | info->handle = handle; |
| 192 | |
| 193 | /* The workaround works by reading from /proc/pid/status, so it is |
| 194 | disabled for core files. */ |
| 195 | if (target_has_execution) |
| 196 | info->need_stale_parent_threads_check = 1; |
| 197 | |
| 198 | info->next = thread_db_list; |
| 199 | thread_db_list = info; |
| 200 | |
| 201 | return info; |
| 202 | } |
| 203 | |
| 204 | /* Return the thread_db_info object representing the bookkeeping |
| 205 | related to process PID, if any; NULL otherwise. */ |
| 206 | |
| 207 | static struct thread_db_info * |
| 208 | get_thread_db_info (int pid) |
| 209 | { |
| 210 | struct thread_db_info *info; |
| 211 | |
| 212 | for (info = thread_db_list; info; info = info->next) |
| 213 | if (pid == info->pid) |
| 214 | return info; |
| 215 | |
| 216 | return NULL; |
| 217 | } |
| 218 | |
| 219 | /* When PID has exited or has been detached, we no longer want to keep |
| 220 | track of it as using libpthread. Call this function to discard |
| 221 | thread_db related info related to PID. Note that this closes |
| 222 | LIBTHREAD_DB_SO's dlopen'ed handle. */ |
| 223 | |
| 224 | static void |
| 225 | delete_thread_db_info (int pid) |
| 226 | { |
| 227 | struct thread_db_info *info, *info_prev; |
| 228 | |
| 229 | info_prev = NULL; |
| 230 | |
| 231 | for (info = thread_db_list; info; info_prev = info, info = info->next) |
| 232 | if (pid == info->pid) |
| 233 | break; |
| 234 | |
| 235 | if (info == NULL) |
| 236 | return; |
| 237 | |
| 238 | if (info->handle != NULL) |
| 239 | dlclose (info->handle); |
| 240 | |
| 241 | xfree (info->filename); |
| 242 | |
| 243 | if (info_prev) |
| 244 | info_prev->next = info->next; |
| 245 | else |
| 246 | thread_db_list = info->next; |
| 247 | |
| 248 | xfree (info); |
| 249 | } |
| 250 | |
| 251 | /* Use "struct private_thread_info" to cache thread state. This is |
| 252 | a substantial optimization. */ |
| 253 | |
| 254 | struct private_thread_info |
| 255 | { |
| 256 | /* Flag set when we see a TD_DEATH event for this thread. */ |
| 257 | unsigned int dying:1; |
| 258 | |
| 259 | /* Cached thread state. */ |
| 260 | td_thrhandle_t th; |
| 261 | thread_t tid; |
| 262 | }; |
| 263 | \f |
| 264 | |
| 265 | static char * |
| 266 | thread_db_err_str (td_err_e err) |
| 267 | { |
| 268 | static char buf[64]; |
| 269 | |
| 270 | switch (err) |
| 271 | { |
| 272 | case TD_OK: |
| 273 | return "generic 'call succeeded'"; |
| 274 | case TD_ERR: |
| 275 | return "generic error"; |
| 276 | case TD_NOTHR: |
| 277 | return "no thread to satisfy query"; |
| 278 | case TD_NOSV: |
| 279 | return "no sync handle to satisfy query"; |
| 280 | case TD_NOLWP: |
| 281 | return "no LWP to satisfy query"; |
| 282 | case TD_BADPH: |
| 283 | return "invalid process handle"; |
| 284 | case TD_BADTH: |
| 285 | return "invalid thread handle"; |
| 286 | case TD_BADSH: |
| 287 | return "invalid synchronization handle"; |
| 288 | case TD_BADTA: |
| 289 | return "invalid thread agent"; |
| 290 | case TD_BADKEY: |
| 291 | return "invalid key"; |
| 292 | case TD_NOMSG: |
| 293 | return "no event message for getmsg"; |
| 294 | case TD_NOFPREGS: |
| 295 | return "FPU register set not available"; |
| 296 | case TD_NOLIBTHREAD: |
| 297 | return "application not linked with libthread"; |
| 298 | case TD_NOEVENT: |
| 299 | return "requested event is not supported"; |
| 300 | case TD_NOCAPAB: |
| 301 | return "capability not available"; |
| 302 | case TD_DBERR: |
| 303 | return "debugger service failed"; |
| 304 | case TD_NOAPLIC: |
| 305 | return "operation not applicable to"; |
| 306 | case TD_NOTSD: |
| 307 | return "no thread-specific data for this thread"; |
| 308 | case TD_MALLOC: |
| 309 | return "malloc failed"; |
| 310 | case TD_PARTIALREG: |
| 311 | return "only part of register set was written/read"; |
| 312 | case TD_NOXREGS: |
| 313 | return "X register set not available for this thread"; |
| 314 | #ifdef THREAD_DB_HAS_TD_NOTALLOC |
| 315 | case TD_NOTALLOC: |
| 316 | return "thread has not yet allocated TLS for given module"; |
| 317 | #endif |
| 318 | #ifdef THREAD_DB_HAS_TD_VERSION |
| 319 | case TD_VERSION: |
| 320 | return "versions of libpthread and libthread_db do not match"; |
| 321 | #endif |
| 322 | #ifdef THREAD_DB_HAS_TD_NOTLS |
| 323 | case TD_NOTLS: |
| 324 | return "there is no TLS segment in the given module"; |
| 325 | #endif |
| 326 | default: |
| 327 | snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
| 328 | return buf; |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | /* Fetch the user-level thread id of PTID. */ |
| 333 | |
| 334 | static struct thread_info * |
| 335 | thread_from_lwp (ptid_t ptid) |
| 336 | { |
| 337 | td_thrhandle_t th; |
| 338 | td_thrinfo_t ti; |
| 339 | td_err_e err; |
| 340 | struct thread_db_info *info; |
| 341 | struct thread_info *tp; |
| 342 | |
| 343 | /* Just in case td_ta_map_lwp2thr doesn't initialize it completely. */ |
| 344 | th.th_unique = 0; |
| 345 | |
| 346 | /* This ptid comes from linux-nat.c, which should always fill in the |
| 347 | LWP. */ |
| 348 | gdb_assert (ptid_get_lwp (ptid) != 0); |
| 349 | |
| 350 | info = get_thread_db_info (ptid_get_pid (ptid)); |
| 351 | |
| 352 | /* Access an lwp we know is stopped. */ |
| 353 | info->proc_handle.ptid = ptid; |
| 354 | err = info->td_ta_map_lwp2thr_p (info->thread_agent, ptid_get_lwp (ptid), |
| 355 | &th); |
| 356 | if (err != TD_OK) |
| 357 | error (_("Cannot find user-level thread for LWP %ld: %s"), |
| 358 | ptid_get_lwp (ptid), thread_db_err_str (err)); |
| 359 | |
| 360 | err = info->td_thr_get_info_p (&th, &ti); |
| 361 | if (err != TD_OK) |
| 362 | error (_("thread_get_info_callback: cannot get thread info: %s"), |
| 363 | thread_db_err_str (err)); |
| 364 | |
| 365 | /* Fill the cache. */ |
| 366 | tp = find_thread_ptid (ptid); |
| 367 | return record_thread (info, tp, ptid, &th, &ti); |
| 368 | } |
| 369 | \f |
| 370 | |
| 371 | /* See linux-nat.h. */ |
| 372 | |
| 373 | int |
| 374 | thread_db_notice_clone (ptid_t parent, ptid_t child) |
| 375 | { |
| 376 | td_thrhandle_t th; |
| 377 | td_thrinfo_t ti; |
| 378 | td_err_e err; |
| 379 | struct thread_db_info *info; |
| 380 | |
| 381 | info = get_thread_db_info (ptid_get_pid (child)); |
| 382 | |
| 383 | if (info == NULL) |
| 384 | return 0; |
| 385 | |
| 386 | thread_from_lwp (child); |
| 387 | |
| 388 | /* If we do not know about the main thread yet, this would be a good |
| 389 | time to find it. */ |
| 390 | thread_from_lwp (parent); |
| 391 | return 1; |
| 392 | } |
| 393 | |
| 394 | static void * |
| 395 | verbose_dlsym (void *handle, const char *name) |
| 396 | { |
| 397 | void *sym = dlsym (handle, name); |
| 398 | if (sym == NULL) |
| 399 | warning (_("Symbol \"%s\" not found in libthread_db: %s"), |
| 400 | name, dlerror ()); |
| 401 | return sym; |
| 402 | } |
| 403 | |
| 404 | /* Verify inferior's '\0'-terminated symbol VER_SYMBOL starts with "%d.%d" and |
| 405 | return 1 if this version is lower (and not equal) to |
| 406 | VER_MAJOR_MIN.VER_MINOR_MIN. Return 0 in all other cases. */ |
| 407 | |
| 408 | static int |
| 409 | inferior_has_bug (const char *ver_symbol, int ver_major_min, int ver_minor_min) |
| 410 | { |
| 411 | struct bound_minimal_symbol version_msym; |
| 412 | CORE_ADDR version_addr; |
| 413 | char *version; |
| 414 | int err, got, retval = 0; |
| 415 | |
| 416 | version_msym = lookup_minimal_symbol (ver_symbol, NULL, NULL); |
| 417 | if (version_msym.minsym == NULL) |
| 418 | return 0; |
| 419 | |
| 420 | version_addr = BMSYMBOL_VALUE_ADDRESS (version_msym); |
| 421 | got = target_read_string (version_addr, &version, 32, &err); |
| 422 | if (err == 0 && memchr (version, 0, got) == &version[got -1]) |
| 423 | { |
| 424 | int major, minor; |
| 425 | |
| 426 | retval = (sscanf (version, "%d.%d", &major, &minor) == 2 |
| 427 | && (major < ver_major_min |
| 428 | || (major == ver_major_min && minor < ver_minor_min))); |
| 429 | } |
| 430 | xfree (version); |
| 431 | |
| 432 | return retval; |
| 433 | } |
| 434 | |
| 435 | /* Similar as thread_db_find_new_threads_1, but try to silently ignore errors |
| 436 | if appropriate. |
| 437 | |
| 438 | Return 1 if the caller should abort libthread_db initialization. Return 0 |
| 439 | otherwise. */ |
| 440 | |
| 441 | static int |
| 442 | thread_db_find_new_threads_silently (ptid_t ptid) |
| 443 | { |
| 444 | |
| 445 | TRY |
| 446 | { |
| 447 | thread_db_find_new_threads_2 (ptid, 1); |
| 448 | } |
| 449 | |
| 450 | CATCH (except, RETURN_MASK_ERROR) |
| 451 | { |
| 452 | if (libthread_db_debug) |
| 453 | exception_fprintf (gdb_stdlog, except, |
| 454 | "Warning: thread_db_find_new_threads_silently: "); |
| 455 | |
| 456 | /* There is a bug fixed between nptl 2.6.1 and 2.7 by |
| 457 | commit 7d9d8bd18906fdd17364f372b160d7ab896ce909 |
| 458 | where calls to td_thr_get_info fail with TD_ERR for statically linked |
| 459 | executables if td_thr_get_info is called before glibc has initialized |
| 460 | itself. |
| 461 | |
| 462 | If the nptl bug is NOT present in the inferior and still thread_db |
| 463 | reports an error return 1. It means the inferior has corrupted thread |
| 464 | list and GDB should fall back only to LWPs. |
| 465 | |
| 466 | If the nptl bug is present in the inferior return 0 to silently ignore |
| 467 | such errors, and let gdb enumerate threads again later. In such case |
| 468 | GDB cannot properly display LWPs if the inferior thread list is |
| 469 | corrupted. For core files it does not apply, no 'later enumeration' |
| 470 | is possible. */ |
| 471 | |
| 472 | if (!target_has_execution || !inferior_has_bug ("nptl_version", 2, 7)) |
| 473 | { |
| 474 | exception_fprintf (gdb_stderr, except, |
| 475 | _("Warning: couldn't activate thread debugging " |
| 476 | "using libthread_db: ")); |
| 477 | return 1; |
| 478 | } |
| 479 | } |
| 480 | END_CATCH |
| 481 | |
| 482 | return 0; |
| 483 | } |
| 484 | |
| 485 | /* Lookup a library in which given symbol resides. |
| 486 | Note: this is looking in GDB process, not in the inferior. |
| 487 | Returns library name, or NULL. */ |
| 488 | |
| 489 | static const char * |
| 490 | dladdr_to_soname (const void *addr) |
| 491 | { |
| 492 | Dl_info info; |
| 493 | |
| 494 | if (dladdr (addr, &info) != 0) |
| 495 | return info.dli_fname; |
| 496 | return NULL; |
| 497 | } |
| 498 | |
| 499 | /* Attempt to initialize dlopen()ed libthread_db, described by INFO. |
| 500 | Return 1 on success. |
| 501 | Failure could happen if libthread_db does not have symbols we expect, |
| 502 | or when it refuses to work with the current inferior (e.g. due to |
| 503 | version mismatch between libthread_db and libpthread). */ |
| 504 | |
| 505 | static int |
| 506 | try_thread_db_load_1 (struct thread_db_info *info) |
| 507 | { |
| 508 | td_err_e err; |
| 509 | |
| 510 | /* Initialize pointers to the dynamic library functions we will use. |
| 511 | Essential functions first. */ |
| 512 | |
| 513 | #define TDB_VERBOSE_DLSYM(info, func) \ |
| 514 | info->func ## _p = (func ## _ftype *) verbose_dlsym (info->handle, #func) |
| 515 | |
| 516 | #define TDB_DLSYM(info, func) \ |
| 517 | info->func ## _p = (func ## _ftype *) dlsym (info->handle, #func) |
| 518 | |
| 519 | #define CHK(a) \ |
| 520 | do \ |
| 521 | { \ |
| 522 | if ((a) == NULL) \ |
| 523 | return 0; \ |
| 524 | } while (0) |
| 525 | |
| 526 | CHK (TDB_VERBOSE_DLSYM (info, td_init)); |
| 527 | |
| 528 | err = info->td_init_p (); |
| 529 | if (err != TD_OK) |
| 530 | { |
| 531 | warning (_("Cannot initialize libthread_db: %s"), |
| 532 | thread_db_err_str (err)); |
| 533 | return 0; |
| 534 | } |
| 535 | |
| 536 | CHK (TDB_VERBOSE_DLSYM (info, td_ta_new)); |
| 537 | |
| 538 | /* Initialize the structure that identifies the child process. */ |
| 539 | info->proc_handle.ptid = inferior_ptid; |
| 540 | |
| 541 | /* Now attempt to open a connection to the thread library. */ |
| 542 | err = info->td_ta_new_p (&info->proc_handle, &info->thread_agent); |
| 543 | if (err != TD_OK) |
| 544 | { |
| 545 | if (libthread_db_debug) |
| 546 | fprintf_unfiltered (gdb_stdlog, _("td_ta_new failed: %s\n"), |
| 547 | thread_db_err_str (err)); |
| 548 | else |
| 549 | switch (err) |
| 550 | { |
| 551 | case TD_NOLIBTHREAD: |
| 552 | #ifdef THREAD_DB_HAS_TD_VERSION |
| 553 | case TD_VERSION: |
| 554 | #endif |
| 555 | /* The errors above are not unexpected and silently ignored: |
| 556 | they just mean we haven't found correct version of |
| 557 | libthread_db yet. */ |
| 558 | break; |
| 559 | default: |
| 560 | warning (_("td_ta_new failed: %s"), thread_db_err_str (err)); |
| 561 | } |
| 562 | return 0; |
| 563 | } |
| 564 | |
| 565 | /* These are essential. */ |
| 566 | CHK (TDB_VERBOSE_DLSYM (info, td_ta_map_lwp2thr)); |
| 567 | CHK (TDB_VERBOSE_DLSYM (info, td_thr_validate)); |
| 568 | CHK (TDB_VERBOSE_DLSYM (info, td_thr_get_info)); |
| 569 | |
| 570 | /* These are not essential. */ |
| 571 | TDB_DLSYM (info, td_thr_tls_get_addr); |
| 572 | TDB_DLSYM (info, td_thr_tlsbase); |
| 573 | |
| 574 | /* It's best to avoid td_ta_thr_iter if possible. That walks data |
| 575 | structures in the inferior's address space that may be corrupted, |
| 576 | or, if the target is running, may change while we walk them. If |
| 577 | there's execution (and /proc is mounted), then we're already |
| 578 | attached to all LWPs. Use thread_from_lwp, which uses |
| 579 | td_ta_map_lwp2thr instead, which does not walk the thread list. |
| 580 | |
| 581 | td_ta_map_lwp2thr uses ps_get_thread_area, but we can't use that |
| 582 | currently on core targets, as it uses ptrace directly. */ |
| 583 | if (target_has_execution |
| 584 | && linux_proc_task_list_dir_exists (ptid_get_pid (inferior_ptid))) |
| 585 | info->td_ta_thr_iter_p = NULL; |
| 586 | else |
| 587 | CHK (TDB_VERBOSE_DLSYM (info, td_ta_thr_iter)); |
| 588 | |
| 589 | #undef TDB_VERBOSE_DLSYM |
| 590 | #undef TDB_DLSYM |
| 591 | #undef CHK |
| 592 | |
| 593 | if (info->td_ta_thr_iter_p == NULL) |
| 594 | { |
| 595 | struct lwp_info *lp; |
| 596 | int pid = ptid_get_pid (inferior_ptid); |
| 597 | |
| 598 | linux_stop_and_wait_all_lwps (); |
| 599 | |
| 600 | ALL_LWPS (lp) |
| 601 | if (ptid_get_pid (lp->ptid) == pid) |
| 602 | thread_from_lwp (lp->ptid); |
| 603 | |
| 604 | linux_unstop_all_lwps (); |
| 605 | } |
| 606 | else if (thread_db_find_new_threads_silently (inferior_ptid) != 0) |
| 607 | { |
| 608 | /* Even if libthread_db initializes, if the thread list is |
| 609 | corrupted, we'd not manage to list any threads. Better reject this |
| 610 | thread_db, and fall back to at least listing LWPs. */ |
| 611 | return 0; |
| 612 | } |
| 613 | |
| 614 | printf_unfiltered (_("[Thread debugging using libthread_db enabled]\n")); |
| 615 | |
| 616 | if (*libthread_db_search_path || libthread_db_debug) |
| 617 | { |
| 618 | struct ui_file *file; |
| 619 | const char *library; |
| 620 | |
| 621 | library = dladdr_to_soname ((const void *) *info->td_ta_new_p); |
| 622 | if (library == NULL) |
| 623 | library = LIBTHREAD_DB_SO; |
| 624 | |
| 625 | /* If we'd print this to gdb_stdout when debug output is |
| 626 | disabled, still print it to gdb_stdout if debug output is |
| 627 | enabled. User visible output should not depend on debug |
| 628 | settings. */ |
| 629 | file = *libthread_db_search_path != '\0' ? gdb_stdout : gdb_stdlog; |
| 630 | fprintf_unfiltered (file, _("Using host libthread_db library \"%s\".\n"), |
| 631 | library); |
| 632 | } |
| 633 | |
| 634 | /* The thread library was detected. Activate the thread_db target |
| 635 | if this is the first process using it. */ |
| 636 | if (thread_db_list->next == NULL) |
| 637 | push_target (&thread_db_ops); |
| 638 | |
| 639 | return 1; |
| 640 | } |
| 641 | |
| 642 | /* Attempt to use LIBRARY as libthread_db. LIBRARY could be absolute, |
| 643 | relative, or just LIBTHREAD_DB. */ |
| 644 | |
| 645 | static int |
| 646 | try_thread_db_load (const char *library, int check_auto_load_safe) |
| 647 | { |
| 648 | void *handle; |
| 649 | struct thread_db_info *info; |
| 650 | |
| 651 | if (libthread_db_debug) |
| 652 | fprintf_unfiltered (gdb_stdlog, |
| 653 | _("Trying host libthread_db library: %s.\n"), |
| 654 | library); |
| 655 | |
| 656 | if (check_auto_load_safe) |
| 657 | { |
| 658 | if (access (library, R_OK) != 0) |
| 659 | { |
| 660 | /* Do not print warnings by file_is_auto_load_safe if the library does |
| 661 | not exist at this place. */ |
| 662 | if (libthread_db_debug) |
| 663 | fprintf_unfiltered (gdb_stdlog, _("open failed: %s.\n"), |
| 664 | safe_strerror (errno)); |
| 665 | return 0; |
| 666 | } |
| 667 | |
| 668 | if (!file_is_auto_load_safe (library, _("auto-load: Loading libthread-db " |
| 669 | "library \"%s\" from explicit " |
| 670 | "directory.\n"), |
| 671 | library)) |
| 672 | return 0; |
| 673 | } |
| 674 | |
| 675 | handle = dlopen (library, RTLD_NOW); |
| 676 | if (handle == NULL) |
| 677 | { |
| 678 | if (libthread_db_debug) |
| 679 | fprintf_unfiltered (gdb_stdlog, _("dlopen failed: %s.\n"), dlerror ()); |
| 680 | return 0; |
| 681 | } |
| 682 | |
| 683 | if (libthread_db_debug && strchr (library, '/') == NULL) |
| 684 | { |
| 685 | void *td_init; |
| 686 | |
| 687 | td_init = dlsym (handle, "td_init"); |
| 688 | if (td_init != NULL) |
| 689 | { |
| 690 | const char *const libpath = dladdr_to_soname (td_init); |
| 691 | |
| 692 | if (libpath != NULL) |
| 693 | fprintf_unfiltered (gdb_stdlog, _("Host %s resolved to: %s.\n"), |
| 694 | library, libpath); |
| 695 | } |
| 696 | } |
| 697 | |
| 698 | info = add_thread_db_info (handle); |
| 699 | |
| 700 | /* Do not save system library name, that one is always trusted. */ |
| 701 | if (strchr (library, '/') != NULL) |
| 702 | info->filename = gdb_realpath (library); |
| 703 | |
| 704 | if (try_thread_db_load_1 (info)) |
| 705 | return 1; |
| 706 | |
| 707 | /* This library "refused" to work on current inferior. */ |
| 708 | delete_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 709 | return 0; |
| 710 | } |
| 711 | |
| 712 | /* Subroutine of try_thread_db_load_from_pdir to simplify it. |
| 713 | Try loading libthread_db in directory(OBJ)/SUBDIR. |
| 714 | SUBDIR may be NULL. It may also be something like "../lib64". |
| 715 | The result is true for success. */ |
| 716 | |
| 717 | static int |
| 718 | try_thread_db_load_from_pdir_1 (struct objfile *obj, const char *subdir) |
| 719 | { |
| 720 | struct cleanup *cleanup; |
| 721 | char *path, *cp; |
| 722 | int result; |
| 723 | const char *obj_name = objfile_name (obj); |
| 724 | int alloc_len; |
| 725 | |
| 726 | if (obj_name[0] != '/') |
| 727 | { |
| 728 | warning (_("Expected absolute pathname for libpthread in the" |
| 729 | " inferior, but got %s."), obj_name); |
| 730 | return 0; |
| 731 | } |
| 732 | |
| 733 | alloc_len = (strlen (obj_name) |
| 734 | + (subdir ? strlen (subdir) + 1 : 0) |
| 735 | + 1 + strlen (LIBTHREAD_DB_SO) + 1); |
| 736 | path = (char *) xmalloc (alloc_len); |
| 737 | cleanup = make_cleanup (xfree, path); |
| 738 | |
| 739 | strcpy (path, obj_name); |
| 740 | cp = strrchr (path, '/'); |
| 741 | /* This should at minimum hit the first character. */ |
| 742 | gdb_assert (cp != NULL); |
| 743 | cp[1] = '\0'; |
| 744 | if (subdir != NULL) |
| 745 | { |
| 746 | strcat (cp, subdir); |
| 747 | strcat (cp, "/"); |
| 748 | } |
| 749 | strcat (cp, LIBTHREAD_DB_SO); |
| 750 | |
| 751 | result = try_thread_db_load (path, 1); |
| 752 | |
| 753 | do_cleanups (cleanup); |
| 754 | return result; |
| 755 | } |
| 756 | |
| 757 | /* Handle $pdir in libthread-db-search-path. |
| 758 | Look for libthread_db in directory(libpthread)/SUBDIR. |
| 759 | SUBDIR may be NULL. It may also be something like "../lib64". |
| 760 | The result is true for success. */ |
| 761 | |
| 762 | static int |
| 763 | try_thread_db_load_from_pdir (const char *subdir) |
| 764 | { |
| 765 | struct objfile *obj; |
| 766 | |
| 767 | if (!auto_load_thread_db) |
| 768 | return 0; |
| 769 | |
| 770 | ALL_OBJFILES (obj) |
| 771 | if (libpthread_name_p (objfile_name (obj))) |
| 772 | { |
| 773 | if (try_thread_db_load_from_pdir_1 (obj, subdir)) |
| 774 | return 1; |
| 775 | |
| 776 | /* We may have found the separate-debug-info version of |
| 777 | libpthread, and it may live in a directory without a matching |
| 778 | libthread_db. */ |
| 779 | if (obj->separate_debug_objfile_backlink != NULL) |
| 780 | return try_thread_db_load_from_pdir_1 (obj->separate_debug_objfile_backlink, |
| 781 | subdir); |
| 782 | |
| 783 | return 0; |
| 784 | } |
| 785 | |
| 786 | return 0; |
| 787 | } |
| 788 | |
| 789 | /* Handle $sdir in libthread-db-search-path. |
| 790 | Look for libthread_db in the system dirs, or wherever a plain |
| 791 | dlopen(file_without_path) will look. |
| 792 | The result is true for success. */ |
| 793 | |
| 794 | static int |
| 795 | try_thread_db_load_from_sdir (void) |
| 796 | { |
| 797 | return try_thread_db_load (LIBTHREAD_DB_SO, 0); |
| 798 | } |
| 799 | |
| 800 | /* Try to load libthread_db from directory DIR of length DIR_LEN. |
| 801 | The result is true for success. */ |
| 802 | |
| 803 | static int |
| 804 | try_thread_db_load_from_dir (const char *dir, size_t dir_len) |
| 805 | { |
| 806 | struct cleanup *cleanup; |
| 807 | char *path; |
| 808 | int result; |
| 809 | |
| 810 | if (!auto_load_thread_db) |
| 811 | return 0; |
| 812 | |
| 813 | path = (char *) xmalloc (dir_len + 1 + strlen (LIBTHREAD_DB_SO) + 1); |
| 814 | cleanup = make_cleanup (xfree, path); |
| 815 | |
| 816 | memcpy (path, dir, dir_len); |
| 817 | path[dir_len] = '/'; |
| 818 | strcpy (path + dir_len + 1, LIBTHREAD_DB_SO); |
| 819 | |
| 820 | result = try_thread_db_load (path, 1); |
| 821 | |
| 822 | do_cleanups (cleanup); |
| 823 | return result; |
| 824 | } |
| 825 | |
| 826 | /* Search libthread_db_search_path for libthread_db which "agrees" |
| 827 | to work on current inferior. |
| 828 | The result is true for success. */ |
| 829 | |
| 830 | static int |
| 831 | thread_db_load_search (void) |
| 832 | { |
| 833 | VEC (char_ptr) *dir_vec; |
| 834 | struct cleanup *cleanups; |
| 835 | char *this_dir; |
| 836 | int i, rc = 0; |
| 837 | |
| 838 | dir_vec = dirnames_to_char_ptr_vec (libthread_db_search_path); |
| 839 | cleanups = make_cleanup_free_char_ptr_vec (dir_vec); |
| 840 | |
| 841 | for (i = 0; VEC_iterate (char_ptr, dir_vec, i, this_dir); ++i) |
| 842 | { |
| 843 | const int pdir_len = sizeof ("$pdir") - 1; |
| 844 | size_t this_dir_len; |
| 845 | |
| 846 | this_dir_len = strlen (this_dir); |
| 847 | |
| 848 | if (strncmp (this_dir, "$pdir", pdir_len) == 0 |
| 849 | && (this_dir[pdir_len] == '\0' |
| 850 | || this_dir[pdir_len] == '/')) |
| 851 | { |
| 852 | char *subdir = NULL; |
| 853 | struct cleanup *free_subdir_cleanup |
| 854 | = make_cleanup (null_cleanup, NULL); |
| 855 | |
| 856 | if (this_dir[pdir_len] == '/') |
| 857 | { |
| 858 | subdir = (char *) xmalloc (strlen (this_dir)); |
| 859 | make_cleanup (xfree, subdir); |
| 860 | strcpy (subdir, this_dir + pdir_len + 1); |
| 861 | } |
| 862 | rc = try_thread_db_load_from_pdir (subdir); |
| 863 | do_cleanups (free_subdir_cleanup); |
| 864 | if (rc) |
| 865 | break; |
| 866 | } |
| 867 | else if (strcmp (this_dir, "$sdir") == 0) |
| 868 | { |
| 869 | if (try_thread_db_load_from_sdir ()) |
| 870 | { |
| 871 | rc = 1; |
| 872 | break; |
| 873 | } |
| 874 | } |
| 875 | else |
| 876 | { |
| 877 | if (try_thread_db_load_from_dir (this_dir, this_dir_len)) |
| 878 | { |
| 879 | rc = 1; |
| 880 | break; |
| 881 | } |
| 882 | } |
| 883 | } |
| 884 | |
| 885 | do_cleanups (cleanups); |
| 886 | if (libthread_db_debug) |
| 887 | fprintf_unfiltered (gdb_stdlog, |
| 888 | _("thread_db_load_search returning %d\n"), rc); |
| 889 | return rc; |
| 890 | } |
| 891 | |
| 892 | /* Return non-zero if the inferior has a libpthread. */ |
| 893 | |
| 894 | static int |
| 895 | has_libpthread (void) |
| 896 | { |
| 897 | struct objfile *obj; |
| 898 | |
| 899 | ALL_OBJFILES (obj) |
| 900 | if (libpthread_name_p (objfile_name (obj))) |
| 901 | return 1; |
| 902 | |
| 903 | return 0; |
| 904 | } |
| 905 | |
| 906 | /* Attempt to load and initialize libthread_db. |
| 907 | Return 1 on success. */ |
| 908 | |
| 909 | static int |
| 910 | thread_db_load (void) |
| 911 | { |
| 912 | struct thread_db_info *info; |
| 913 | |
| 914 | info = get_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 915 | |
| 916 | if (info != NULL) |
| 917 | return 1; |
| 918 | |
| 919 | /* Don't attempt to use thread_db on executables not running |
| 920 | yet. */ |
| 921 | if (!target_has_registers) |
| 922 | return 0; |
| 923 | |
| 924 | /* Don't attempt to use thread_db for remote targets. */ |
| 925 | if (!(target_can_run (¤t_target) || core_bfd)) |
| 926 | return 0; |
| 927 | |
| 928 | if (thread_db_load_search ()) |
| 929 | return 1; |
| 930 | |
| 931 | /* We couldn't find a libthread_db. |
| 932 | If the inferior has a libpthread warn the user. */ |
| 933 | if (has_libpthread ()) |
| 934 | { |
| 935 | warning (_("Unable to find libthread_db matching inferior's thread" |
| 936 | " library, thread debugging will not be available.")); |
| 937 | return 0; |
| 938 | } |
| 939 | |
| 940 | /* Either this executable isn't using libpthread at all, or it is |
| 941 | statically linked. Since we can't easily distinguish these two cases, |
| 942 | no warning is issued. */ |
| 943 | return 0; |
| 944 | } |
| 945 | |
| 946 | static void |
| 947 | check_thread_signals (void) |
| 948 | { |
| 949 | if (!thread_signals) |
| 950 | { |
| 951 | sigset_t mask; |
| 952 | int i; |
| 953 | |
| 954 | lin_thread_get_thread_signals (&mask); |
| 955 | sigemptyset (&thread_stop_set); |
| 956 | sigemptyset (&thread_print_set); |
| 957 | |
| 958 | for (i = 1; i < NSIG; i++) |
| 959 | { |
| 960 | if (sigismember (&mask, i)) |
| 961 | { |
| 962 | if (signal_stop_update (gdb_signal_from_host (i), 0)) |
| 963 | sigaddset (&thread_stop_set, i); |
| 964 | if (signal_print_update (gdb_signal_from_host (i), 0)) |
| 965 | sigaddset (&thread_print_set, i); |
| 966 | thread_signals = 1; |
| 967 | } |
| 968 | } |
| 969 | } |
| 970 | } |
| 971 | |
| 972 | /* Check whether thread_db is usable. This function is called when |
| 973 | an inferior is created (or otherwise acquired, e.g. attached to) |
| 974 | and when new shared libraries are loaded into a running process. */ |
| 975 | |
| 976 | void |
| 977 | check_for_thread_db (void) |
| 978 | { |
| 979 | /* Do nothing if we couldn't load libthread_db.so.1. */ |
| 980 | if (!thread_db_load ()) |
| 981 | return; |
| 982 | } |
| 983 | |
| 984 | /* This function is called via the new_objfile observer. */ |
| 985 | |
| 986 | static void |
| 987 | thread_db_new_objfile (struct objfile *objfile) |
| 988 | { |
| 989 | /* This observer must always be called with inferior_ptid set |
| 990 | correctly. */ |
| 991 | |
| 992 | if (objfile != NULL |
| 993 | /* libpthread with separate debug info has its debug info file already |
| 994 | loaded (and notified without successful thread_db initialization) |
| 995 | the time observer_notify_new_objfile is called for the library itself. |
| 996 | Static executables have their separate debug info loaded already |
| 997 | before the inferior has started. */ |
| 998 | && objfile->separate_debug_objfile_backlink == NULL |
| 999 | /* Only check for thread_db if we loaded libpthread, |
| 1000 | or if this is the main symbol file. |
| 1001 | We need to check OBJF_MAINLINE to handle the case of debugging |
| 1002 | a statically linked executable AND the symbol file is specified AFTER |
| 1003 | the exec file is loaded (e.g., gdb -c core ; file foo). |
| 1004 | For dynamically linked executables, libpthread can be near the end |
| 1005 | of the list of shared libraries to load, and in an app of several |
| 1006 | thousand shared libraries, this can otherwise be painful. */ |
| 1007 | && ((objfile->flags & OBJF_MAINLINE) != 0 |
| 1008 | || libpthread_name_p (objfile_name (objfile)))) |
| 1009 | check_for_thread_db (); |
| 1010 | } |
| 1011 | |
| 1012 | static void |
| 1013 | check_pid_namespace_match (void) |
| 1014 | { |
| 1015 | /* Check is only relevant for local targets targets. */ |
| 1016 | if (target_can_run (¤t_target)) |
| 1017 | { |
| 1018 | /* If the child is in a different PID namespace, its idea of its |
| 1019 | PID will differ from our idea of its PID. When we scan the |
| 1020 | child's thread list, we'll mistakenly think it has no threads |
| 1021 | since the thread PID fields won't match the PID we give to |
| 1022 | libthread_db. */ |
| 1023 | if (!linux_ns_same (ptid_get_pid (inferior_ptid), LINUX_NS_PID)) |
| 1024 | { |
| 1025 | warning (_ ("Target and debugger are in different PID " |
| 1026 | "namespaces; thread lists and other data are " |
| 1027 | "likely unreliable")); |
| 1028 | } |
| 1029 | } |
| 1030 | } |
| 1031 | |
| 1032 | /* This function is called via the inferior_created observer. |
| 1033 | This handles the case of debugging statically linked executables. */ |
| 1034 | |
| 1035 | static void |
| 1036 | thread_db_inferior_created (struct target_ops *target, int from_tty) |
| 1037 | { |
| 1038 | check_pid_namespace_match (); |
| 1039 | check_for_thread_db (); |
| 1040 | } |
| 1041 | |
| 1042 | /* Update the thread's state (what's displayed in "info threads"), |
| 1043 | from libthread_db thread state information. */ |
| 1044 | |
| 1045 | static void |
| 1046 | update_thread_state (struct private_thread_info *priv, |
| 1047 | const td_thrinfo_t *ti_p) |
| 1048 | { |
| 1049 | priv->dying = (ti_p->ti_state == TD_THR_UNKNOWN |
| 1050 | || ti_p->ti_state == TD_THR_ZOMBIE); |
| 1051 | } |
| 1052 | |
| 1053 | /* Record a new thread in GDB's thread list. Creates the thread's |
| 1054 | private info. If TP is NULL or TP is marked as having exited, |
| 1055 | creates a new thread. Otherwise, uses TP. */ |
| 1056 | |
| 1057 | static struct thread_info * |
| 1058 | record_thread (struct thread_db_info *info, |
| 1059 | struct thread_info *tp, |
| 1060 | ptid_t ptid, const td_thrhandle_t *th_p, |
| 1061 | const td_thrinfo_t *ti_p) |
| 1062 | { |
| 1063 | td_err_e err; |
| 1064 | struct private_thread_info *priv; |
| 1065 | int new_thread = (tp == NULL); |
| 1066 | |
| 1067 | /* A thread ID of zero may mean the thread library has not |
| 1068 | initialized yet. Leave private == NULL until the thread library |
| 1069 | has initialized. */ |
| 1070 | if (ti_p->ti_tid == 0) |
| 1071 | return tp; |
| 1072 | |
| 1073 | /* Construct the thread's private data. */ |
| 1074 | priv = XCNEW (struct private_thread_info); |
| 1075 | |
| 1076 | priv->th = *th_p; |
| 1077 | priv->tid = ti_p->ti_tid; |
| 1078 | update_thread_state (priv, ti_p); |
| 1079 | |
| 1080 | /* Add the thread to GDB's thread list. If we already know about a |
| 1081 | thread with this PTID, but it's marked exited, then the kernel |
| 1082 | reused the tid of an old thread. */ |
| 1083 | if (tp == NULL || tp->state == THREAD_EXITED) |
| 1084 | tp = add_thread_with_info (ptid, priv); |
| 1085 | else |
| 1086 | tp->priv = priv; |
| 1087 | |
| 1088 | if (target_has_execution) |
| 1089 | check_thread_signals (); |
| 1090 | |
| 1091 | return tp; |
| 1092 | } |
| 1093 | |
| 1094 | static void |
| 1095 | thread_db_detach (struct target_ops *ops, const char *args, int from_tty) |
| 1096 | { |
| 1097 | struct target_ops *target_beneath = find_target_beneath (ops); |
| 1098 | struct thread_db_info *info; |
| 1099 | |
| 1100 | info = get_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 1101 | |
| 1102 | if (info) |
| 1103 | delete_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 1104 | |
| 1105 | target_beneath->to_detach (target_beneath, args, from_tty); |
| 1106 | |
| 1107 | /* NOTE: From this point on, inferior_ptid is null_ptid. */ |
| 1108 | |
| 1109 | /* If there are no more processes using libpthread, detach the |
| 1110 | thread_db target ops. */ |
| 1111 | if (!thread_db_list) |
| 1112 | unpush_target (&thread_db_ops); |
| 1113 | } |
| 1114 | |
| 1115 | static ptid_t |
| 1116 | thread_db_wait (struct target_ops *ops, |
| 1117 | ptid_t ptid, struct target_waitstatus *ourstatus, |
| 1118 | int options) |
| 1119 | { |
| 1120 | struct thread_db_info *info; |
| 1121 | struct target_ops *beneath = find_target_beneath (ops); |
| 1122 | |
| 1123 | ptid = beneath->to_wait (beneath, ptid, ourstatus, options); |
| 1124 | |
| 1125 | if (ourstatus->kind == TARGET_WAITKIND_IGNORE) |
| 1126 | return ptid; |
| 1127 | |
| 1128 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
| 1129 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) |
| 1130 | return ptid; |
| 1131 | |
| 1132 | info = get_thread_db_info (ptid_get_pid (ptid)); |
| 1133 | |
| 1134 | /* If this process isn't using thread_db, we're done. */ |
| 1135 | if (info == NULL) |
| 1136 | return ptid; |
| 1137 | |
| 1138 | if (ourstatus->kind == TARGET_WAITKIND_EXECD) |
| 1139 | { |
| 1140 | /* New image, it may or may not end up using thread_db. Assume |
| 1141 | not unless we find otherwise. */ |
| 1142 | delete_thread_db_info (ptid_get_pid (ptid)); |
| 1143 | if (!thread_db_list) |
| 1144 | unpush_target (&thread_db_ops); |
| 1145 | |
| 1146 | return ptid; |
| 1147 | } |
| 1148 | |
| 1149 | /* Fill in the thread's user-level thread id and status. */ |
| 1150 | thread_from_lwp (ptid); |
| 1151 | |
| 1152 | return ptid; |
| 1153 | } |
| 1154 | |
| 1155 | static void |
| 1156 | thread_db_mourn_inferior (struct target_ops *ops) |
| 1157 | { |
| 1158 | struct target_ops *target_beneath = find_target_beneath (ops); |
| 1159 | |
| 1160 | delete_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 1161 | |
| 1162 | target_beneath->to_mourn_inferior (target_beneath); |
| 1163 | |
| 1164 | /* Detach thread_db target ops. */ |
| 1165 | if (!thread_db_list) |
| 1166 | unpush_target (ops); |
| 1167 | } |
| 1168 | |
| 1169 | struct callback_data |
| 1170 | { |
| 1171 | struct thread_db_info *info; |
| 1172 | int new_threads; |
| 1173 | }; |
| 1174 | |
| 1175 | static int |
| 1176 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) |
| 1177 | { |
| 1178 | td_thrinfo_t ti; |
| 1179 | td_err_e err; |
| 1180 | ptid_t ptid; |
| 1181 | struct thread_info *tp; |
| 1182 | struct callback_data *cb_data = (struct callback_data *) data; |
| 1183 | struct thread_db_info *info = cb_data->info; |
| 1184 | |
| 1185 | err = info->td_thr_get_info_p (th_p, &ti); |
| 1186 | if (err != TD_OK) |
| 1187 | error (_("find_new_threads_callback: cannot get thread info: %s"), |
| 1188 | thread_db_err_str (err)); |
| 1189 | |
| 1190 | if (ti.ti_lid == -1) |
| 1191 | { |
| 1192 | /* A thread with kernel thread ID -1 is either a thread that |
| 1193 | exited and was joined, or a thread that is being created but |
| 1194 | hasn't started yet, and that is reusing the tcb/stack of a |
| 1195 | thread that previously exited and was joined. (glibc marks |
| 1196 | terminated and joined threads with kernel thread ID -1. See |
| 1197 | glibc PR17707. */ |
| 1198 | if (libthread_db_debug) |
| 1199 | fprintf_unfiltered (gdb_stdlog, |
| 1200 | "thread_db: skipping exited and " |
| 1201 | "joined thread (0x%lx)\n", |
| 1202 | (unsigned long) ti.ti_tid); |
| 1203 | return 0; |
| 1204 | } |
| 1205 | |
| 1206 | if (ti.ti_tid == 0) |
| 1207 | { |
| 1208 | /* A thread ID of zero means that this is the main thread, but |
| 1209 | glibc has not yet initialized thread-local storage and the |
| 1210 | pthread library. We do not know what the thread's TID will |
| 1211 | be yet. */ |
| 1212 | |
| 1213 | /* In that case, we're not stopped in a fork syscall and don't |
| 1214 | need this glibc bug workaround. */ |
| 1215 | info->need_stale_parent_threads_check = 0; |
| 1216 | |
| 1217 | return 0; |
| 1218 | } |
| 1219 | |
| 1220 | /* Ignore stale parent threads, caused by glibc/BZ5983. This is a |
| 1221 | bit expensive, as it needs to open /proc/pid/status, so try to |
| 1222 | avoid doing the work if we know we don't have to. */ |
| 1223 | if (info->need_stale_parent_threads_check) |
| 1224 | { |
| 1225 | int tgid = linux_proc_get_tgid (ti.ti_lid); |
| 1226 | |
| 1227 | if (tgid != -1 && tgid != info->pid) |
| 1228 | return 0; |
| 1229 | } |
| 1230 | |
| 1231 | ptid = ptid_build (info->pid, ti.ti_lid, 0); |
| 1232 | tp = find_thread_ptid (ptid); |
| 1233 | if (tp == NULL || tp->priv == NULL) |
| 1234 | record_thread (info, tp, ptid, th_p, &ti); |
| 1235 | |
| 1236 | return 0; |
| 1237 | } |
| 1238 | |
| 1239 | /* Helper for thread_db_find_new_threads_2. |
| 1240 | Returns number of new threads found. */ |
| 1241 | |
| 1242 | static int |
| 1243 | find_new_threads_once (struct thread_db_info *info, int iteration, |
| 1244 | td_err_e *errp) |
| 1245 | { |
| 1246 | struct callback_data data; |
| 1247 | td_err_e err = TD_ERR; |
| 1248 | |
| 1249 | data.info = info; |
| 1250 | data.new_threads = 0; |
| 1251 | |
| 1252 | /* See comment in thread_db_update_thread_list. */ |
| 1253 | gdb_assert (info->td_ta_thr_iter_p != NULL); |
| 1254 | |
| 1255 | TRY |
| 1256 | { |
| 1257 | /* Iterate over all user-space threads to discover new threads. */ |
| 1258 | err = info->td_ta_thr_iter_p (info->thread_agent, |
| 1259 | find_new_threads_callback, |
| 1260 | &data, |
| 1261 | TD_THR_ANY_STATE, |
| 1262 | TD_THR_LOWEST_PRIORITY, |
| 1263 | TD_SIGNO_MASK, |
| 1264 | TD_THR_ANY_USER_FLAGS); |
| 1265 | } |
| 1266 | CATCH (except, RETURN_MASK_ERROR) |
| 1267 | { |
| 1268 | if (libthread_db_debug) |
| 1269 | { |
| 1270 | exception_fprintf (gdb_stdlog, except, |
| 1271 | "Warning: find_new_threads_once: "); |
| 1272 | } |
| 1273 | } |
| 1274 | END_CATCH |
| 1275 | |
| 1276 | if (libthread_db_debug) |
| 1277 | { |
| 1278 | fprintf_unfiltered (gdb_stdlog, |
| 1279 | _("Found %d new threads in iteration %d.\n"), |
| 1280 | data.new_threads, iteration); |
| 1281 | } |
| 1282 | |
| 1283 | if (errp != NULL) |
| 1284 | *errp = err; |
| 1285 | |
| 1286 | return data.new_threads; |
| 1287 | } |
| 1288 | |
| 1289 | /* Search for new threads, accessing memory through stopped thread |
| 1290 | PTID. If UNTIL_NO_NEW is true, repeat searching until several |
| 1291 | searches in a row do not discover any new threads. */ |
| 1292 | |
| 1293 | static void |
| 1294 | thread_db_find_new_threads_2 (ptid_t ptid, int until_no_new) |
| 1295 | { |
| 1296 | td_err_e err = TD_OK; |
| 1297 | struct thread_db_info *info; |
| 1298 | int i, loop; |
| 1299 | |
| 1300 | info = get_thread_db_info (ptid_get_pid (ptid)); |
| 1301 | |
| 1302 | /* Access an lwp we know is stopped. */ |
| 1303 | info->proc_handle.ptid = ptid; |
| 1304 | |
| 1305 | if (until_no_new) |
| 1306 | { |
| 1307 | /* Require 4 successive iterations which do not find any new threads. |
| 1308 | The 4 is a heuristic: there is an inherent race here, and I have |
| 1309 | seen that 2 iterations in a row are not always sufficient to |
| 1310 | "capture" all threads. */ |
| 1311 | for (i = 0, loop = 0; loop < 4 && err == TD_OK; ++i, ++loop) |
| 1312 | if (find_new_threads_once (info, i, &err) != 0) |
| 1313 | { |
| 1314 | /* Found some new threads. Restart the loop from beginning. */ |
| 1315 | loop = -1; |
| 1316 | } |
| 1317 | } |
| 1318 | else |
| 1319 | find_new_threads_once (info, 0, &err); |
| 1320 | |
| 1321 | if (err != TD_OK) |
| 1322 | error (_("Cannot find new threads: %s"), thread_db_err_str (err)); |
| 1323 | } |
| 1324 | |
| 1325 | static void |
| 1326 | thread_db_find_new_threads_1 (ptid_t ptid) |
| 1327 | { |
| 1328 | thread_db_find_new_threads_2 (ptid, 0); |
| 1329 | } |
| 1330 | |
| 1331 | /* Implement the to_update_thread_list target method for this |
| 1332 | target. */ |
| 1333 | |
| 1334 | static void |
| 1335 | thread_db_update_thread_list (struct target_ops *ops) |
| 1336 | { |
| 1337 | struct thread_db_info *info; |
| 1338 | struct inferior *inf; |
| 1339 | |
| 1340 | prune_threads (); |
| 1341 | |
| 1342 | ALL_INFERIORS (inf) |
| 1343 | { |
| 1344 | struct thread_info *thread; |
| 1345 | |
| 1346 | if (inf->pid == 0) |
| 1347 | continue; |
| 1348 | |
| 1349 | info = get_thread_db_info (inf->pid); |
| 1350 | if (info == NULL) |
| 1351 | continue; |
| 1352 | |
| 1353 | thread = any_live_thread_of_process (inf->pid); |
| 1354 | if (thread == NULL || thread->executing) |
| 1355 | continue; |
| 1356 | |
| 1357 | /* It's best to avoid td_ta_thr_iter if possible. That walks |
| 1358 | data structures in the inferior's address space that may be |
| 1359 | corrupted, or, if the target is running, the list may change |
| 1360 | while we walk it. In the latter case, it's possible that a |
| 1361 | thread exits just at the exact time that causes GDB to get |
| 1362 | stuck in an infinite loop. To avoid pausing all threads |
| 1363 | whenever the core wants to refresh the thread list, we |
| 1364 | instead use thread_from_lwp immediately when we see an LWP |
| 1365 | stop. That uses thread_db entry points that do not walk |
| 1366 | libpthread's thread list, so should be safe, as well as more |
| 1367 | efficient. */ |
| 1368 | if (target_has_execution_1 (thread->ptid)) |
| 1369 | continue; |
| 1370 | |
| 1371 | thread_db_find_new_threads_1 (thread->ptid); |
| 1372 | } |
| 1373 | |
| 1374 | /* Give the beneath target a chance to do extra processing. */ |
| 1375 | ops->beneath->to_update_thread_list (ops->beneath); |
| 1376 | } |
| 1377 | |
| 1378 | static char * |
| 1379 | thread_db_pid_to_str (struct target_ops *ops, ptid_t ptid) |
| 1380 | { |
| 1381 | struct thread_info *thread_info = find_thread_ptid (ptid); |
| 1382 | struct target_ops *beneath; |
| 1383 | |
| 1384 | if (thread_info != NULL && thread_info->priv != NULL) |
| 1385 | { |
| 1386 | static char buf[64]; |
| 1387 | thread_t tid; |
| 1388 | |
| 1389 | tid = thread_info->priv->tid; |
| 1390 | snprintf (buf, sizeof (buf), "Thread 0x%lx (LWP %ld)", |
| 1391 | (unsigned long) tid, ptid_get_lwp (ptid)); |
| 1392 | |
| 1393 | return buf; |
| 1394 | } |
| 1395 | |
| 1396 | beneath = find_target_beneath (ops); |
| 1397 | return beneath->to_pid_to_str (beneath, ptid); |
| 1398 | } |
| 1399 | |
| 1400 | /* Return a string describing the state of the thread specified by |
| 1401 | INFO. */ |
| 1402 | |
| 1403 | static char * |
| 1404 | thread_db_extra_thread_info (struct target_ops *self, |
| 1405 | struct thread_info *info) |
| 1406 | { |
| 1407 | if (info->priv == NULL) |
| 1408 | return NULL; |
| 1409 | |
| 1410 | if (info->priv->dying) |
| 1411 | return "Exiting"; |
| 1412 | |
| 1413 | return NULL; |
| 1414 | } |
| 1415 | |
| 1416 | /* Get the address of the thread local variable in load module LM which |
| 1417 | is stored at OFFSET within the thread local storage for thread PTID. */ |
| 1418 | |
| 1419 | static CORE_ADDR |
| 1420 | thread_db_get_thread_local_address (struct target_ops *ops, |
| 1421 | ptid_t ptid, |
| 1422 | CORE_ADDR lm, |
| 1423 | CORE_ADDR offset) |
| 1424 | { |
| 1425 | struct thread_info *thread_info; |
| 1426 | struct target_ops *beneath; |
| 1427 | |
| 1428 | /* Find the matching thread. */ |
| 1429 | thread_info = find_thread_ptid (ptid); |
| 1430 | |
| 1431 | /* We may not have discovered the thread yet. */ |
| 1432 | if (thread_info != NULL && thread_info->priv == NULL) |
| 1433 | thread_info = thread_from_lwp (ptid); |
| 1434 | |
| 1435 | if (thread_info != NULL && thread_info->priv != NULL) |
| 1436 | { |
| 1437 | td_err_e err; |
| 1438 | psaddr_t address; |
| 1439 | struct thread_db_info *info; |
| 1440 | |
| 1441 | info = get_thread_db_info (ptid_get_pid (ptid)); |
| 1442 | |
| 1443 | /* Finally, get the address of the variable. */ |
| 1444 | if (lm != 0) |
| 1445 | { |
| 1446 | /* glibc doesn't provide the needed interface. */ |
| 1447 | if (!info->td_thr_tls_get_addr_p) |
| 1448 | throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR, |
| 1449 | _("No TLS library support")); |
| 1450 | |
| 1451 | /* Note the cast through uintptr_t: this interface only works if |
| 1452 | a target address fits in a psaddr_t, which is a host pointer. |
| 1453 | So a 32-bit debugger can not access 64-bit TLS through this. */ |
| 1454 | err = info->td_thr_tls_get_addr_p (&thread_info->priv->th, |
| 1455 | (psaddr_t)(uintptr_t) lm, |
| 1456 | offset, &address); |
| 1457 | } |
| 1458 | else |
| 1459 | { |
| 1460 | /* If glibc doesn't provide the needed interface throw an error |
| 1461 | that LM is zero - normally cases it should not be. */ |
| 1462 | if (!info->td_thr_tlsbase_p) |
| 1463 | throw_error (TLS_LOAD_MODULE_NOT_FOUND_ERROR, |
| 1464 | _("TLS load module not found")); |
| 1465 | |
| 1466 | /* This code path handles the case of -static -pthread executables: |
| 1467 | https://sourceware.org/ml/libc-help/2014-03/msg00024.html |
| 1468 | For older GNU libc r_debug.r_map is NULL. For GNU libc after |
| 1469 | PR libc/16831 due to GDB PR threads/16954 LOAD_MODULE is also NULL. |
| 1470 | The constant number 1 depends on GNU __libc_setup_tls |
| 1471 | initialization of l_tls_modid to 1. */ |
| 1472 | err = info->td_thr_tlsbase_p (&thread_info->priv->th, |
| 1473 | 1, &address); |
| 1474 | address = (char *) address + offset; |
| 1475 | } |
| 1476 | |
| 1477 | #ifdef THREAD_DB_HAS_TD_NOTALLOC |
| 1478 | /* The memory hasn't been allocated, yet. */ |
| 1479 | if (err == TD_NOTALLOC) |
| 1480 | /* Now, if libthread_db provided the initialization image's |
| 1481 | address, we *could* try to build a non-lvalue value from |
| 1482 | the initialization image. */ |
| 1483 | throw_error (TLS_NOT_ALLOCATED_YET_ERROR, |
| 1484 | _("TLS not allocated yet")); |
| 1485 | #endif |
| 1486 | |
| 1487 | /* Something else went wrong. */ |
| 1488 | if (err != TD_OK) |
| 1489 | throw_error (TLS_GENERIC_ERROR, |
| 1490 | (("%s")), thread_db_err_str (err)); |
| 1491 | |
| 1492 | /* Cast assuming host == target. Joy. */ |
| 1493 | /* Do proper sign extension for the target. */ |
| 1494 | gdb_assert (exec_bfd); |
| 1495 | return (bfd_get_sign_extend_vma (exec_bfd) > 0 |
| 1496 | ? (CORE_ADDR) (intptr_t) address |
| 1497 | : (CORE_ADDR) (uintptr_t) address); |
| 1498 | } |
| 1499 | |
| 1500 | beneath = find_target_beneath (ops); |
| 1501 | return beneath->to_get_thread_local_address (beneath, ptid, lm, offset); |
| 1502 | } |
| 1503 | |
| 1504 | /* Implement the to_get_ada_task_ptid target method for this target. */ |
| 1505 | |
| 1506 | static ptid_t |
| 1507 | thread_db_get_ada_task_ptid (struct target_ops *self, long lwp, long thread) |
| 1508 | { |
| 1509 | /* NPTL uses a 1:1 model, so the LWP id suffices. */ |
| 1510 | return ptid_build (ptid_get_pid (inferior_ptid), lwp, 0); |
| 1511 | } |
| 1512 | |
| 1513 | static void |
| 1514 | thread_db_resume (struct target_ops *ops, |
| 1515 | ptid_t ptid, int step, enum gdb_signal signo) |
| 1516 | { |
| 1517 | struct target_ops *beneath = find_target_beneath (ops); |
| 1518 | struct thread_db_info *info; |
| 1519 | |
| 1520 | if (ptid_equal (ptid, minus_one_ptid)) |
| 1521 | info = get_thread_db_info (ptid_get_pid (inferior_ptid)); |
| 1522 | else |
| 1523 | info = get_thread_db_info (ptid_get_pid (ptid)); |
| 1524 | |
| 1525 | /* This workaround is only needed for child fork lwps stopped in a |
| 1526 | PTRACE_O_TRACEFORK event. When the inferior is resumed, the |
| 1527 | workaround can be disabled. */ |
| 1528 | if (info) |
| 1529 | info->need_stale_parent_threads_check = 0; |
| 1530 | |
| 1531 | beneath->to_resume (beneath, ptid, step, signo); |
| 1532 | } |
| 1533 | |
| 1534 | /* qsort helper function for info_auto_load_libthread_db, sort the |
| 1535 | thread_db_info pointers primarily by their FILENAME and secondarily by their |
| 1536 | PID, both in ascending order. */ |
| 1537 | |
| 1538 | static int |
| 1539 | info_auto_load_libthread_db_compare (const void *ap, const void *bp) |
| 1540 | { |
| 1541 | struct thread_db_info *a = *(struct thread_db_info **) ap; |
| 1542 | struct thread_db_info *b = *(struct thread_db_info **) bp; |
| 1543 | int retval; |
| 1544 | |
| 1545 | retval = strcmp (a->filename, b->filename); |
| 1546 | if (retval) |
| 1547 | return retval; |
| 1548 | |
| 1549 | return (a->pid > b->pid) - (a->pid - b->pid); |
| 1550 | } |
| 1551 | |
| 1552 | /* Implement 'info auto-load libthread-db'. */ |
| 1553 | |
| 1554 | static void |
| 1555 | info_auto_load_libthread_db (char *args, int from_tty) |
| 1556 | { |
| 1557 | struct ui_out *uiout = current_uiout; |
| 1558 | const char *cs = args ? args : ""; |
| 1559 | struct thread_db_info *info, **array; |
| 1560 | unsigned info_count, unique_filenames; |
| 1561 | size_t max_filename_len, max_pids_len, pids_len; |
| 1562 | struct cleanup *back_to; |
| 1563 | char *pids; |
| 1564 | int i; |
| 1565 | |
| 1566 | cs = skip_spaces_const (cs); |
| 1567 | if (*cs) |
| 1568 | error (_("'info auto-load libthread-db' does not accept any parameters")); |
| 1569 | |
| 1570 | info_count = 0; |
| 1571 | for (info = thread_db_list; info; info = info->next) |
| 1572 | if (info->filename != NULL) |
| 1573 | info_count++; |
| 1574 | |
| 1575 | array = XNEWVEC (struct thread_db_info *, info_count); |
| 1576 | back_to = make_cleanup (xfree, array); |
| 1577 | |
| 1578 | info_count = 0; |
| 1579 | for (info = thread_db_list; info; info = info->next) |
| 1580 | if (info->filename != NULL) |
| 1581 | array[info_count++] = info; |
| 1582 | |
| 1583 | /* Sort ARRAY by filenames and PIDs. */ |
| 1584 | |
| 1585 | qsort (array, info_count, sizeof (*array), |
| 1586 | info_auto_load_libthread_db_compare); |
| 1587 | |
| 1588 | /* Calculate the number of unique filenames (rows) and the maximum string |
| 1589 | length of PIDs list for the unique filenames (columns). */ |
| 1590 | |
| 1591 | unique_filenames = 0; |
| 1592 | max_filename_len = 0; |
| 1593 | max_pids_len = 0; |
| 1594 | pids_len = 0; |
| 1595 | for (i = 0; i < info_count; i++) |
| 1596 | { |
| 1597 | int pid = array[i]->pid; |
| 1598 | size_t this_pid_len; |
| 1599 | |
| 1600 | for (this_pid_len = 0; pid != 0; pid /= 10) |
| 1601 | this_pid_len++; |
| 1602 | |
| 1603 | if (i == 0 || strcmp (array[i - 1]->filename, array[i]->filename) != 0) |
| 1604 | { |
| 1605 | unique_filenames++; |
| 1606 | max_filename_len = max (max_filename_len, |
| 1607 | strlen (array[i]->filename)); |
| 1608 | |
| 1609 | if (i > 0) |
| 1610 | { |
| 1611 | pids_len -= strlen (", "); |
| 1612 | max_pids_len = max (max_pids_len, pids_len); |
| 1613 | } |
| 1614 | pids_len = 0; |
| 1615 | } |
| 1616 | pids_len += this_pid_len + strlen (", "); |
| 1617 | } |
| 1618 | if (i) |
| 1619 | { |
| 1620 | pids_len -= strlen (", "); |
| 1621 | max_pids_len = max (max_pids_len, pids_len); |
| 1622 | } |
| 1623 | |
| 1624 | /* Table header shifted right by preceding "libthread-db: " would not match |
| 1625 | its columns. */ |
| 1626 | if (info_count > 0 && args == auto_load_info_scripts_pattern_nl) |
| 1627 | ui_out_text (uiout, "\n"); |
| 1628 | |
| 1629 | make_cleanup_ui_out_table_begin_end (uiout, 2, unique_filenames, |
| 1630 | "LinuxThreadDbTable"); |
| 1631 | |
| 1632 | ui_out_table_header (uiout, max_filename_len, ui_left, "filename", |
| 1633 | "Filename"); |
| 1634 | ui_out_table_header (uiout, pids_len, ui_left, "PIDs", "Pids"); |
| 1635 | ui_out_table_body (uiout); |
| 1636 | |
| 1637 | pids = (char *) xmalloc (max_pids_len + 1); |
| 1638 | make_cleanup (xfree, pids); |
| 1639 | |
| 1640 | /* Note I is incremented inside the cycle, not at its end. */ |
| 1641 | for (i = 0; i < info_count;) |
| 1642 | { |
| 1643 | struct cleanup *chain = make_cleanup_ui_out_tuple_begin_end (uiout, NULL); |
| 1644 | char *pids_end; |
| 1645 | |
| 1646 | info = array[i]; |
| 1647 | ui_out_field_string (uiout, "filename", info->filename); |
| 1648 | pids_end = pids; |
| 1649 | |
| 1650 | while (i < info_count && strcmp (info->filename, array[i]->filename) == 0) |
| 1651 | { |
| 1652 | if (pids_end != pids) |
| 1653 | { |
| 1654 | *pids_end++ = ','; |
| 1655 | *pids_end++ = ' '; |
| 1656 | } |
| 1657 | pids_end += xsnprintf (pids_end, &pids[max_pids_len + 1] - pids_end, |
| 1658 | "%u", array[i]->pid); |
| 1659 | gdb_assert (pids_end < &pids[max_pids_len + 1]); |
| 1660 | |
| 1661 | i++; |
| 1662 | } |
| 1663 | *pids_end = '\0'; |
| 1664 | |
| 1665 | ui_out_field_string (uiout, "pids", pids); |
| 1666 | |
| 1667 | ui_out_text (uiout, "\n"); |
| 1668 | do_cleanups (chain); |
| 1669 | } |
| 1670 | |
| 1671 | do_cleanups (back_to); |
| 1672 | |
| 1673 | if (info_count == 0) |
| 1674 | ui_out_message (uiout, 0, _("No auto-loaded libthread-db.\n")); |
| 1675 | } |
| 1676 | |
| 1677 | static void |
| 1678 | init_thread_db_ops (void) |
| 1679 | { |
| 1680 | thread_db_ops.to_shortname = "multi-thread"; |
| 1681 | thread_db_ops.to_longname = "multi-threaded child process."; |
| 1682 | thread_db_ops.to_doc = "Threads and pthreads support."; |
| 1683 | thread_db_ops.to_detach = thread_db_detach; |
| 1684 | thread_db_ops.to_wait = thread_db_wait; |
| 1685 | thread_db_ops.to_resume = thread_db_resume; |
| 1686 | thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior; |
| 1687 | thread_db_ops.to_update_thread_list = thread_db_update_thread_list; |
| 1688 | thread_db_ops.to_pid_to_str = thread_db_pid_to_str; |
| 1689 | thread_db_ops.to_stratum = thread_stratum; |
| 1690 | thread_db_ops.to_has_thread_control = tc_schedlock; |
| 1691 | thread_db_ops.to_get_thread_local_address |
| 1692 | = thread_db_get_thread_local_address; |
| 1693 | thread_db_ops.to_extra_thread_info = thread_db_extra_thread_info; |
| 1694 | thread_db_ops.to_get_ada_task_ptid = thread_db_get_ada_task_ptid; |
| 1695 | thread_db_ops.to_magic = OPS_MAGIC; |
| 1696 | |
| 1697 | complete_target_initialization (&thread_db_ops); |
| 1698 | } |
| 1699 | |
| 1700 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 1701 | extern initialize_file_ftype _initialize_thread_db; |
| 1702 | |
| 1703 | void |
| 1704 | _initialize_thread_db (void) |
| 1705 | { |
| 1706 | init_thread_db_ops (); |
| 1707 | |
| 1708 | /* Defer loading of libthread_db.so until inferior is running. |
| 1709 | This allows gdb to load correct libthread_db for a given |
| 1710 | executable -- there could be multiple versions of glibc, |
| 1711 | and until there is a running inferior, we can't tell which |
| 1712 | libthread_db is the correct one to load. */ |
| 1713 | |
| 1714 | libthread_db_search_path = xstrdup (LIBTHREAD_DB_SEARCH_PATH); |
| 1715 | |
| 1716 | add_setshow_optional_filename_cmd ("libthread-db-search-path", |
| 1717 | class_support, |
| 1718 | &libthread_db_search_path, _("\ |
| 1719 | Set search path for libthread_db."), _("\ |
| 1720 | Show the current search path or libthread_db."), _("\ |
| 1721 | This path is used to search for libthread_db to be loaded into \ |
| 1722 | gdb itself.\n\ |
| 1723 | Its value is a colon (':') separate list of directories to search.\n\ |
| 1724 | Setting the search path to an empty list resets it to its default value."), |
| 1725 | set_libthread_db_search_path, |
| 1726 | NULL, |
| 1727 | &setlist, &showlist); |
| 1728 | |
| 1729 | add_setshow_zuinteger_cmd ("libthread-db", class_maintenance, |
| 1730 | &libthread_db_debug, _("\ |
| 1731 | Set libthread-db debugging."), _("\ |
| 1732 | Show libthread-db debugging."), _("\ |
| 1733 | When non-zero, libthread-db debugging is enabled."), |
| 1734 | NULL, |
| 1735 | show_libthread_db_debug, |
| 1736 | &setdebuglist, &showdebuglist); |
| 1737 | |
| 1738 | add_setshow_boolean_cmd ("libthread-db", class_support, |
| 1739 | &auto_load_thread_db, _("\ |
| 1740 | Enable or disable auto-loading of inferior specific libthread_db."), _("\ |
| 1741 | Show whether auto-loading inferior specific libthread_db is enabled."), _("\ |
| 1742 | If enabled, libthread_db will be searched in 'set libthread-db-search-path'\n\ |
| 1743 | locations to load libthread_db compatible with the inferior.\n\ |
| 1744 | Standard system libthread_db still gets loaded even with this option off.\n\ |
| 1745 | This options has security implications for untrusted inferiors."), |
| 1746 | NULL, show_auto_load_thread_db, |
| 1747 | auto_load_set_cmdlist_get (), |
| 1748 | auto_load_show_cmdlist_get ()); |
| 1749 | |
| 1750 | add_cmd ("libthread-db", class_info, info_auto_load_libthread_db, |
| 1751 | _("Print the list of loaded inferior specific libthread_db.\n\ |
| 1752 | Usage: info auto-load libthread-db"), |
| 1753 | auto_load_info_cmdlist_get ()); |
| 1754 | |
| 1755 | /* Add ourselves to objfile event chain. */ |
| 1756 | observer_attach_new_objfile (thread_db_new_objfile); |
| 1757 | |
| 1758 | /* Add ourselves to inferior_created event chain. |
| 1759 | This is needed to handle debugging statically linked programs where |
| 1760 | the new_objfile observer won't get called for libpthread. */ |
| 1761 | observer_attach_inferior_created (thread_db_inferior_created); |
| 1762 | } |