| 1 | /* libthread_db assisted debugging support, generic parts. |
| 2 | |
| 3 | Copyright 1999, 2000, 2001, 2003, 2004 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 2 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, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 20 | Boston, MA 02111-1307, USA. */ |
| 21 | |
| 22 | #include "defs.h" |
| 23 | |
| 24 | #include "gdb_assert.h" |
| 25 | #include <dlfcn.h> |
| 26 | #include "gdb_proc_service.h" |
| 27 | #include "gdb_thread_db.h" |
| 28 | |
| 29 | #include "bfd.h" |
| 30 | #include "gdbthread.h" |
| 31 | #include "inferior.h" |
| 32 | #include "symfile.h" |
| 33 | #include "objfiles.h" |
| 34 | #include "target.h" |
| 35 | #include "regcache.h" |
| 36 | #include "solib-svr4.h" |
| 37 | |
| 38 | #ifdef HAVE_GNU_LIBC_VERSION_H |
| 39 | #include <gnu/libc-version.h> |
| 40 | #endif |
| 41 | |
| 42 | #ifndef LIBTHREAD_DB_SO |
| 43 | #define LIBTHREAD_DB_SO "libthread_db.so.1" |
| 44 | #endif |
| 45 | |
| 46 | /* If we're running on GNU/Linux, we must explicitly attach to any new |
| 47 | threads. */ |
| 48 | |
| 49 | /* FIXME: There is certainly some room for improvements: |
| 50 | - Cache LWP ids. |
| 51 | - Bypass libthread_db when fetching or storing registers for |
| 52 | threads bound to a LWP. */ |
| 53 | |
| 54 | /* This module's target vector. */ |
| 55 | static struct target_ops thread_db_ops; |
| 56 | |
| 57 | /* The target vector that we call for things this module can't handle. */ |
| 58 | static struct target_ops *target_beneath; |
| 59 | |
| 60 | /* Pointer to the next function on the objfile event chain. */ |
| 61 | static void (*target_new_objfile_chain) (struct objfile * objfile); |
| 62 | |
| 63 | /* Non-zero if we're using this module's target vector. */ |
| 64 | static int using_thread_db; |
| 65 | |
| 66 | /* Non-zero if we have to keep this module's target vector active |
| 67 | across re-runs. */ |
| 68 | static int keep_thread_db; |
| 69 | |
| 70 | /* Non-zero if we have determined the signals used by the threads |
| 71 | library. */ |
| 72 | static int thread_signals; |
| 73 | static sigset_t thread_stop_set; |
| 74 | static sigset_t thread_print_set; |
| 75 | |
| 76 | /* Structure that identifies the child process for the |
| 77 | <proc_service.h> interface. */ |
| 78 | static struct ps_prochandle proc_handle; |
| 79 | |
| 80 | /* Connection to the libthread_db library. */ |
| 81 | static td_thragent_t *thread_agent; |
| 82 | |
| 83 | /* Pointers to the libthread_db functions. */ |
| 84 | |
| 85 | static td_err_e (*td_init_p) (void); |
| 86 | |
| 87 | static td_err_e (*td_ta_new_p) (struct ps_prochandle * ps, |
| 88 | td_thragent_t **ta); |
| 89 | static td_err_e (*td_ta_map_id2thr_p) (const td_thragent_t *ta, thread_t pt, |
| 90 | td_thrhandle_t *__th); |
| 91 | static td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta, |
| 92 | lwpid_t lwpid, td_thrhandle_t *th); |
| 93 | static td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta, |
| 94 | td_thr_iter_f *callback, void *cbdata_p, |
| 95 | td_thr_state_e state, int ti_pri, |
| 96 | sigset_t *ti_sigmask_p, |
| 97 | unsigned int ti_user_flags); |
| 98 | static td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta, |
| 99 | td_event_e event, td_notify_t *ptr); |
| 100 | static td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta, |
| 101 | td_thr_events_t *event); |
| 102 | static td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta, |
| 103 | td_event_msg_t *msg); |
| 104 | |
| 105 | static td_err_e (*td_thr_validate_p) (const td_thrhandle_t *th); |
| 106 | static td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th, |
| 107 | td_thrinfo_t *infop); |
| 108 | static td_err_e (*td_thr_getfpregs_p) (const td_thrhandle_t *th, |
| 109 | gdb_prfpregset_t *regset); |
| 110 | static td_err_e (*td_thr_getgregs_p) (const td_thrhandle_t *th, |
| 111 | prgregset_t gregs); |
| 112 | static td_err_e (*td_thr_setfpregs_p) (const td_thrhandle_t *th, |
| 113 | const gdb_prfpregset_t *fpregs); |
| 114 | static td_err_e (*td_thr_setgregs_p) (const td_thrhandle_t *th, |
| 115 | prgregset_t gregs); |
| 116 | static td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th, |
| 117 | int event); |
| 118 | |
| 119 | static td_err_e (*td_thr_tls_get_addr_p) (const td_thrhandle_t *th, |
| 120 | void *map_address, |
| 121 | size_t offset, void **address); |
| 122 | |
| 123 | /* Location of the thread creation event breakpoint. The code at this |
| 124 | location in the child process will be called by the pthread library |
| 125 | whenever a new thread is created. By setting a special breakpoint |
| 126 | at this location, GDB can detect when a new thread is created. We |
| 127 | obtain this location via the td_ta_event_addr call. */ |
| 128 | static CORE_ADDR td_create_bp_addr; |
| 129 | |
| 130 | /* Location of the thread death event breakpoint. */ |
| 131 | static CORE_ADDR td_death_bp_addr; |
| 132 | |
| 133 | /* Prototypes for local functions. */ |
| 134 | static void thread_db_find_new_threads (void); |
| 135 | static void attach_thread (ptid_t ptid, const td_thrhandle_t *th_p, |
| 136 | const td_thrinfo_t *ti_p, int verbose); |
| 137 | static void detach_thread (ptid_t ptid, int verbose); |
| 138 | \f |
| 139 | |
| 140 | /* Building process ids. */ |
| 141 | |
| 142 | #define GET_PID(ptid) ptid_get_pid (ptid) |
| 143 | #define GET_LWP(ptid) ptid_get_lwp (ptid) |
| 144 | #define GET_THREAD(ptid) ptid_get_tid (ptid) |
| 145 | |
| 146 | #define is_lwp(ptid) (GET_LWP (ptid) != 0) |
| 147 | #define is_thread(ptid) (GET_THREAD (ptid) != 0) |
| 148 | |
| 149 | #define BUILD_LWP(lwp, pid) ptid_build (pid, lwp, 0) |
| 150 | #define BUILD_THREAD(tid, pid) ptid_build (pid, 0, tid) |
| 151 | \f |
| 152 | |
| 153 | /* Use "struct private_thread_info" to cache thread state. This is |
| 154 | a substantial optimization. */ |
| 155 | |
| 156 | struct private_thread_info |
| 157 | { |
| 158 | /* Flag set when we see a TD_DEATH event for this thread. */ |
| 159 | unsigned int dying:1; |
| 160 | |
| 161 | /* Cached thread state. */ |
| 162 | unsigned int th_valid:1; |
| 163 | unsigned int ti_valid:1; |
| 164 | |
| 165 | td_thrhandle_t th; |
| 166 | td_thrinfo_t ti; |
| 167 | }; |
| 168 | \f |
| 169 | |
| 170 | static char * |
| 171 | thread_db_err_str (td_err_e err) |
| 172 | { |
| 173 | static char buf[64]; |
| 174 | |
| 175 | switch (err) |
| 176 | { |
| 177 | case TD_OK: |
| 178 | return "generic 'call succeeded'"; |
| 179 | case TD_ERR: |
| 180 | return "generic error"; |
| 181 | case TD_NOTHR: |
| 182 | return "no thread to satisfy query"; |
| 183 | case TD_NOSV: |
| 184 | return "no sync handle to satisfy query"; |
| 185 | case TD_NOLWP: |
| 186 | return "no LWP to satisfy query"; |
| 187 | case TD_BADPH: |
| 188 | return "invalid process handle"; |
| 189 | case TD_BADTH: |
| 190 | return "invalid thread handle"; |
| 191 | case TD_BADSH: |
| 192 | return "invalid synchronization handle"; |
| 193 | case TD_BADTA: |
| 194 | return "invalid thread agent"; |
| 195 | case TD_BADKEY: |
| 196 | return "invalid key"; |
| 197 | case TD_NOMSG: |
| 198 | return "no event message for getmsg"; |
| 199 | case TD_NOFPREGS: |
| 200 | return "FPU register set not available"; |
| 201 | case TD_NOLIBTHREAD: |
| 202 | return "application not linked with libthread"; |
| 203 | case TD_NOEVENT: |
| 204 | return "requested event is not supported"; |
| 205 | case TD_NOCAPAB: |
| 206 | return "capability not available"; |
| 207 | case TD_DBERR: |
| 208 | return "debugger service failed"; |
| 209 | case TD_NOAPLIC: |
| 210 | return "operation not applicable to"; |
| 211 | case TD_NOTSD: |
| 212 | return "no thread-specific data for this thread"; |
| 213 | case TD_MALLOC: |
| 214 | return "malloc failed"; |
| 215 | case TD_PARTIALREG: |
| 216 | return "only part of register set was written/read"; |
| 217 | case TD_NOXREGS: |
| 218 | return "X register set not available for this thread"; |
| 219 | default: |
| 220 | snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
| 221 | return buf; |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | static char * |
| 226 | thread_db_state_str (td_thr_state_e state) |
| 227 | { |
| 228 | static char buf[64]; |
| 229 | |
| 230 | switch (state) |
| 231 | { |
| 232 | case TD_THR_STOPPED: |
| 233 | return "stopped by debugger"; |
| 234 | case TD_THR_RUN: |
| 235 | return "runnable"; |
| 236 | case TD_THR_ACTIVE: |
| 237 | return "active"; |
| 238 | case TD_THR_ZOMBIE: |
| 239 | return "zombie"; |
| 240 | case TD_THR_SLEEP: |
| 241 | return "sleeping"; |
| 242 | case TD_THR_STOPPED_ASLEEP: |
| 243 | return "stopped by debugger AND blocked"; |
| 244 | default: |
| 245 | snprintf (buf, sizeof (buf), "unknown thread_db state %d", state); |
| 246 | return buf; |
| 247 | } |
| 248 | } |
| 249 | \f |
| 250 | /* A callback function for td_ta_thr_iter, which we use to map all |
| 251 | threads to LWPs. |
| 252 | |
| 253 | THP is a handle to the current thread; if INFOP is not NULL, the |
| 254 | struct thread_info associated with this thread is returned in |
| 255 | *INFOP. |
| 256 | |
| 257 | If the thread is a zombie, TD_THR_ZOMBIE is returned. Otherwise, |
| 258 | zero is returned to indicate success. */ |
| 259 | |
| 260 | static int |
| 261 | thread_get_info_callback (const td_thrhandle_t *thp, void *infop) |
| 262 | { |
| 263 | td_thrinfo_t ti; |
| 264 | td_err_e err; |
| 265 | struct thread_info *thread_info; |
| 266 | ptid_t thread_ptid; |
| 267 | |
| 268 | err = td_thr_get_info_p (thp, &ti); |
| 269 | if (err != TD_OK) |
| 270 | error ("thread_get_info_callback: cannot get thread info: %s", |
| 271 | thread_db_err_str (err)); |
| 272 | |
| 273 | /* Fill the cache. */ |
| 274 | thread_ptid = BUILD_THREAD (ti.ti_tid, GET_PID (inferior_ptid)); |
| 275 | thread_info = find_thread_pid (thread_ptid); |
| 276 | |
| 277 | /* In the case of a zombie thread, don't continue. We don't want to |
| 278 | attach to it thinking it is a new thread. */ |
| 279 | if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE) |
| 280 | { |
| 281 | if (infop != NULL) |
| 282 | *(struct thread_info **) infop = thread_info; |
| 283 | if (thread_info != NULL) |
| 284 | { |
| 285 | memcpy (&thread_info->private->th, thp, sizeof (*thp)); |
| 286 | thread_info->private->th_valid = 1; |
| 287 | memcpy (&thread_info->private->ti, &ti, sizeof (ti)); |
| 288 | thread_info->private->ti_valid = 1; |
| 289 | } |
| 290 | return TD_THR_ZOMBIE; |
| 291 | } |
| 292 | |
| 293 | if (thread_info == NULL) |
| 294 | { |
| 295 | /* New thread. Attach to it now (why wait?). */ |
| 296 | attach_thread (thread_ptid, thp, &ti, 1); |
| 297 | thread_info = find_thread_pid (thread_ptid); |
| 298 | gdb_assert (thread_info != NULL); |
| 299 | } |
| 300 | |
| 301 | memcpy (&thread_info->private->th, thp, sizeof (*thp)); |
| 302 | thread_info->private->th_valid = 1; |
| 303 | memcpy (&thread_info->private->ti, &ti, sizeof (ti)); |
| 304 | thread_info->private->ti_valid = 1; |
| 305 | |
| 306 | if (infop != NULL) |
| 307 | *(struct thread_info **) infop = thread_info; |
| 308 | |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | /* Accessor functions for the thread_db information, with caching. */ |
| 313 | |
| 314 | static void |
| 315 | thread_db_map_id2thr (struct thread_info *thread_info, int fatal) |
| 316 | { |
| 317 | td_err_e err; |
| 318 | |
| 319 | if (thread_info->private->th_valid) |
| 320 | return; |
| 321 | |
| 322 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (thread_info->ptid), |
| 323 | &thread_info->private->th); |
| 324 | if (err != TD_OK) |
| 325 | { |
| 326 | if (fatal) |
| 327 | error ("Cannot find thread %ld: %s", |
| 328 | (long) GET_THREAD (thread_info->ptid), |
| 329 | thread_db_err_str (err)); |
| 330 | } |
| 331 | else |
| 332 | thread_info->private->th_valid = 1; |
| 333 | } |
| 334 | |
| 335 | static td_thrinfo_t * |
| 336 | thread_db_get_info (struct thread_info *thread_info) |
| 337 | { |
| 338 | td_err_e err; |
| 339 | |
| 340 | if (thread_info->private->ti_valid) |
| 341 | return &thread_info->private->ti; |
| 342 | |
| 343 | if (!thread_info->private->th_valid) |
| 344 | thread_db_map_id2thr (thread_info, 1); |
| 345 | |
| 346 | err = |
| 347 | td_thr_get_info_p (&thread_info->private->th, &thread_info->private->ti); |
| 348 | if (err != TD_OK) |
| 349 | error ("thread_db_get_info: cannot get thread info: %s", |
| 350 | thread_db_err_str (err)); |
| 351 | |
| 352 | thread_info->private->ti_valid = 1; |
| 353 | return &thread_info->private->ti; |
| 354 | } |
| 355 | \f |
| 356 | /* Convert between user-level thread ids and LWP ids. */ |
| 357 | |
| 358 | static ptid_t |
| 359 | thread_from_lwp (ptid_t ptid) |
| 360 | { |
| 361 | td_thrhandle_t th; |
| 362 | td_err_e err; |
| 363 | struct thread_info *thread_info; |
| 364 | ptid_t thread_ptid; |
| 365 | |
| 366 | if (GET_LWP (ptid) == 0) |
| 367 | ptid = BUILD_LWP (GET_PID (ptid), GET_PID (ptid)); |
| 368 | |
| 369 | gdb_assert (is_lwp (ptid)); |
| 370 | |
| 371 | err = td_ta_map_lwp2thr_p (thread_agent, GET_LWP (ptid), &th); |
| 372 | if (err != TD_OK) |
| 373 | error ("Cannot find user-level thread for LWP %ld: %s", |
| 374 | GET_LWP (ptid), thread_db_err_str (err)); |
| 375 | |
| 376 | thread_info = NULL; |
| 377 | |
| 378 | /* Fetch the thread info. If we get back TD_THR_ZOMBIE, then the |
| 379 | event thread has already died. If another gdb interface has called |
| 380 | thread_alive() previously, the thread won't be found on the thread list |
| 381 | anymore. In that case, we don't want to process this ptid anymore |
| 382 | to avoid the possibility of later treating it as a newly |
| 383 | discovered thread id that we should add to the list. Thus, |
| 384 | we return a -1 ptid which is also how the thread list marks a |
| 385 | dead thread. */ |
| 386 | if (thread_get_info_callback (&th, &thread_info) == TD_THR_ZOMBIE |
| 387 | && thread_info == NULL) |
| 388 | return pid_to_ptid (-1); |
| 389 | |
| 390 | gdb_assert (thread_info && thread_info->private->ti_valid); |
| 391 | |
| 392 | return BUILD_THREAD (thread_info->private->ti.ti_tid, GET_PID (ptid)); |
| 393 | } |
| 394 | |
| 395 | static ptid_t |
| 396 | lwp_from_thread (ptid_t ptid) |
| 397 | { |
| 398 | struct thread_info *thread_info; |
| 399 | ptid_t thread_ptid; |
| 400 | |
| 401 | if (!is_thread (ptid)) |
| 402 | return ptid; |
| 403 | |
| 404 | thread_info = find_thread_pid (ptid); |
| 405 | thread_db_get_info (thread_info); |
| 406 | |
| 407 | return BUILD_LWP (thread_info->private->ti.ti_lid, GET_PID (ptid)); |
| 408 | } |
| 409 | \f |
| 410 | |
| 411 | void |
| 412 | thread_db_init (struct target_ops *target) |
| 413 | { |
| 414 | target_beneath = target; |
| 415 | } |
| 416 | |
| 417 | static void * |
| 418 | verbose_dlsym (void *handle, const char *name) |
| 419 | { |
| 420 | void *sym = dlsym (handle, name); |
| 421 | if (sym == NULL) |
| 422 | warning ("Symbol \"%s\" not found in libthread_db: %s", name, dlerror ()); |
| 423 | return sym; |
| 424 | } |
| 425 | |
| 426 | static int |
| 427 | thread_db_load (void) |
| 428 | { |
| 429 | void *handle; |
| 430 | td_err_e err; |
| 431 | |
| 432 | handle = dlopen (LIBTHREAD_DB_SO, RTLD_NOW); |
| 433 | if (handle == NULL) |
| 434 | { |
| 435 | fprintf_filtered (gdb_stderr, "\n\ndlopen failed on '%s' - %s\n", |
| 436 | LIBTHREAD_DB_SO, dlerror ()); |
| 437 | fprintf_filtered (gdb_stderr, |
| 438 | "GDB will not be able to debug pthreads.\n\n"); |
| 439 | return 0; |
| 440 | } |
| 441 | |
| 442 | /* Initialize pointers to the dynamic library functions we will use. |
| 443 | Essential functions first. */ |
| 444 | |
| 445 | td_init_p = verbose_dlsym (handle, "td_init"); |
| 446 | if (td_init_p == NULL) |
| 447 | return 0; |
| 448 | |
| 449 | td_ta_new_p = verbose_dlsym (handle, "td_ta_new"); |
| 450 | if (td_ta_new_p == NULL) |
| 451 | return 0; |
| 452 | |
| 453 | td_ta_map_id2thr_p = verbose_dlsym (handle, "td_ta_map_id2thr"); |
| 454 | if (td_ta_map_id2thr_p == NULL) |
| 455 | return 0; |
| 456 | |
| 457 | td_ta_map_lwp2thr_p = verbose_dlsym (handle, "td_ta_map_lwp2thr"); |
| 458 | if (td_ta_map_lwp2thr_p == NULL) |
| 459 | return 0; |
| 460 | |
| 461 | td_ta_thr_iter_p = verbose_dlsym (handle, "td_ta_thr_iter"); |
| 462 | if (td_ta_thr_iter_p == NULL) |
| 463 | return 0; |
| 464 | |
| 465 | td_thr_validate_p = verbose_dlsym (handle, "td_thr_validate"); |
| 466 | if (td_thr_validate_p == NULL) |
| 467 | return 0; |
| 468 | |
| 469 | td_thr_get_info_p = verbose_dlsym (handle, "td_thr_get_info"); |
| 470 | if (td_thr_get_info_p == NULL) |
| 471 | return 0; |
| 472 | |
| 473 | td_thr_getfpregs_p = verbose_dlsym (handle, "td_thr_getfpregs"); |
| 474 | if (td_thr_getfpregs_p == NULL) |
| 475 | return 0; |
| 476 | |
| 477 | td_thr_getgregs_p = verbose_dlsym (handle, "td_thr_getgregs"); |
| 478 | if (td_thr_getgregs_p == NULL) |
| 479 | return 0; |
| 480 | |
| 481 | td_thr_setfpregs_p = verbose_dlsym (handle, "td_thr_setfpregs"); |
| 482 | if (td_thr_setfpregs_p == NULL) |
| 483 | return 0; |
| 484 | |
| 485 | td_thr_setgregs_p = verbose_dlsym (handle, "td_thr_setgregs"); |
| 486 | if (td_thr_setgregs_p == NULL) |
| 487 | return 0; |
| 488 | |
| 489 | /* Initialize the library. */ |
| 490 | err = td_init_p (); |
| 491 | if (err != TD_OK) |
| 492 | { |
| 493 | warning ("Cannot initialize libthread_db: %s", thread_db_err_str (err)); |
| 494 | return 0; |
| 495 | } |
| 496 | |
| 497 | /* These are not essential. */ |
| 498 | td_ta_event_addr_p = dlsym (handle, "td_ta_event_addr"); |
| 499 | td_ta_set_event_p = dlsym (handle, "td_ta_set_event"); |
| 500 | td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg"); |
| 501 | td_thr_event_enable_p = dlsym (handle, "td_thr_event_enable"); |
| 502 | td_thr_tls_get_addr_p = dlsym (handle, "td_thr_tls_get_addr"); |
| 503 | |
| 504 | return 1; |
| 505 | } |
| 506 | |
| 507 | static td_err_e |
| 508 | enable_thread_event (td_thragent_t *thread_agent, int event, CORE_ADDR *bp) |
| 509 | { |
| 510 | td_notify_t notify; |
| 511 | td_err_e err; |
| 512 | |
| 513 | /* Get the breakpoint address for thread EVENT. */ |
| 514 | err = td_ta_event_addr_p (thread_agent, event, ¬ify); |
| 515 | if (err != TD_OK) |
| 516 | return err; |
| 517 | |
| 518 | /* Set up the breakpoint. */ |
| 519 | (*bp) = gdbarch_convert_from_func_ptr_addr (current_gdbarch, |
| 520 | (CORE_ADDR) notify.u.bptaddr, |
| 521 | ¤t_target); |
| 522 | create_thread_event_breakpoint ((*bp)); |
| 523 | |
| 524 | return TD_OK; |
| 525 | } |
| 526 | |
| 527 | static void |
| 528 | enable_thread_event_reporting (void) |
| 529 | { |
| 530 | td_thr_events_t events; |
| 531 | td_notify_t notify; |
| 532 | td_err_e err; |
| 533 | #ifdef HAVE_GNU_LIBC_VERSION_H |
| 534 | const char *libc_version; |
| 535 | int libc_major, libc_minor; |
| 536 | #endif |
| 537 | |
| 538 | /* We cannot use the thread event reporting facility if these |
| 539 | functions aren't available. */ |
| 540 | if (td_ta_event_addr_p == NULL || td_ta_set_event_p == NULL |
| 541 | || td_ta_event_getmsg_p == NULL || td_thr_event_enable_p == NULL) |
| 542 | return; |
| 543 | |
| 544 | /* Set the process wide mask saying which events we're interested in. */ |
| 545 | td_event_emptyset (&events); |
| 546 | td_event_addset (&events, TD_CREATE); |
| 547 | |
| 548 | #ifdef HAVE_GNU_LIBC_VERSION_H |
| 549 | /* FIXME: kettenis/2000-04-23: The event reporting facility is |
| 550 | broken for TD_DEATH events in glibc 2.1.3, so don't enable it for |
| 551 | now. */ |
| 552 | libc_version = gnu_get_libc_version (); |
| 553 | if (sscanf (libc_version, "%d.%d", &libc_major, &libc_minor) == 2 |
| 554 | && (libc_major > 2 || (libc_major == 2 && libc_minor > 1))) |
| 555 | #endif |
| 556 | td_event_addset (&events, TD_DEATH); |
| 557 | |
| 558 | err = td_ta_set_event_p (thread_agent, &events); |
| 559 | if (err != TD_OK) |
| 560 | { |
| 561 | warning ("Unable to set global thread event mask: %s", |
| 562 | thread_db_err_str (err)); |
| 563 | return; |
| 564 | } |
| 565 | |
| 566 | /* Delete previous thread event breakpoints, if any. */ |
| 567 | remove_thread_event_breakpoints (); |
| 568 | td_create_bp_addr = 0; |
| 569 | td_death_bp_addr = 0; |
| 570 | |
| 571 | /* Set up the thread creation event. */ |
| 572 | err = enable_thread_event (thread_agent, TD_CREATE, &td_create_bp_addr); |
| 573 | if (err != TD_OK) |
| 574 | { |
| 575 | warning ("Unable to get location for thread creation breakpoint: %s", |
| 576 | thread_db_err_str (err)); |
| 577 | return; |
| 578 | } |
| 579 | |
| 580 | /* Set up the thread death event. */ |
| 581 | err = enable_thread_event (thread_agent, TD_DEATH, &td_death_bp_addr); |
| 582 | if (err != TD_OK) |
| 583 | { |
| 584 | warning ("Unable to get location for thread death breakpoint: %s", |
| 585 | thread_db_err_str (err)); |
| 586 | return; |
| 587 | } |
| 588 | } |
| 589 | |
| 590 | static void |
| 591 | disable_thread_event_reporting (void) |
| 592 | { |
| 593 | td_thr_events_t events; |
| 594 | |
| 595 | /* Set the process wide mask saying we aren't interested in any |
| 596 | events anymore. */ |
| 597 | td_event_emptyset (&events); |
| 598 | td_ta_set_event_p (thread_agent, &events); |
| 599 | |
| 600 | /* Delete thread event breakpoints, if any. */ |
| 601 | remove_thread_event_breakpoints (); |
| 602 | td_create_bp_addr = 0; |
| 603 | td_death_bp_addr = 0; |
| 604 | } |
| 605 | |
| 606 | static void |
| 607 | check_thread_signals (void) |
| 608 | { |
| 609 | #ifdef GET_THREAD_SIGNALS |
| 610 | if (!thread_signals) |
| 611 | { |
| 612 | sigset_t mask; |
| 613 | int i; |
| 614 | |
| 615 | GET_THREAD_SIGNALS (&mask); |
| 616 | sigemptyset (&thread_stop_set); |
| 617 | sigemptyset (&thread_print_set); |
| 618 | |
| 619 | for (i = 1; i < NSIG; i++) |
| 620 | { |
| 621 | if (sigismember (&mask, i)) |
| 622 | { |
| 623 | if (signal_stop_update (target_signal_from_host (i), 0)) |
| 624 | sigaddset (&thread_stop_set, i); |
| 625 | if (signal_print_update (target_signal_from_host (i), 0)) |
| 626 | sigaddset (&thread_print_set, i); |
| 627 | thread_signals = 1; |
| 628 | } |
| 629 | } |
| 630 | } |
| 631 | #endif |
| 632 | } |
| 633 | |
| 634 | static void |
| 635 | thread_db_new_objfile (struct objfile *objfile) |
| 636 | { |
| 637 | td_err_e err; |
| 638 | |
| 639 | /* First time through, report that libthread_db was successfuly |
| 640 | loaded. Can't print this in in thread_db_load as, at that stage, |
| 641 | the interpreter and it's console haven't started. The real |
| 642 | problem here is that libthread_db is loaded too early - it should |
| 643 | only be loaded when there is a program to debug. */ |
| 644 | { |
| 645 | static int dejavu; |
| 646 | if (!dejavu) |
| 647 | { |
| 648 | Dl_info info; |
| 649 | const char *library = NULL; |
| 650 | /* Try dladdr. */ |
| 651 | if (dladdr ((*td_ta_new_p), &info) != 0) |
| 652 | library = info.dli_fname; |
| 653 | /* Try dlinfo? */ |
| 654 | if (library == NULL) |
| 655 | /* Paranoid - don't let a NULL path slip through. */ |
| 656 | library = LIBTHREAD_DB_SO; |
| 657 | printf_unfiltered ("Using host libthread_db library \"%s\".\n", |
| 658 | library); |
| 659 | dejavu = 1; |
| 660 | } |
| 661 | } |
| 662 | |
| 663 | /* Don't attempt to use thread_db on targets which can not run |
| 664 | (core files). */ |
| 665 | if (objfile == NULL || !target_has_execution) |
| 666 | { |
| 667 | /* All symbols have been discarded. If the thread_db target is |
| 668 | active, deactivate it now. */ |
| 669 | if (using_thread_db) |
| 670 | { |
| 671 | gdb_assert (proc_handle.pid == 0); |
| 672 | unpush_target (&thread_db_ops); |
| 673 | using_thread_db = 0; |
| 674 | } |
| 675 | |
| 676 | keep_thread_db = 0; |
| 677 | |
| 678 | goto quit; |
| 679 | } |
| 680 | |
| 681 | if (using_thread_db) |
| 682 | /* Nothing to do. The thread library was already detected and the |
| 683 | target vector was already activated. */ |
| 684 | goto quit; |
| 685 | |
| 686 | /* Initialize the structure that identifies the child process. Note |
| 687 | that at this point there is no guarantee that we actually have a |
| 688 | child process. */ |
| 689 | proc_handle.pid = GET_PID (inferior_ptid); |
| 690 | |
| 691 | /* Now attempt to open a connection to the thread library. */ |
| 692 | err = td_ta_new_p (&proc_handle, &thread_agent); |
| 693 | switch (err) |
| 694 | { |
| 695 | case TD_NOLIBTHREAD: |
| 696 | /* No thread library was detected. */ |
| 697 | break; |
| 698 | |
| 699 | case TD_OK: |
| 700 | printf_unfiltered ("[Thread debugging using libthread_db enabled]\n"); |
| 701 | |
| 702 | /* The thread library was detected. Activate the thread_db target. */ |
| 703 | push_target (&thread_db_ops); |
| 704 | using_thread_db = 1; |
| 705 | |
| 706 | /* If the thread library was detected in the main symbol file |
| 707 | itself, we assume that the program was statically linked |
| 708 | against the thread library and well have to keep this |
| 709 | module's target vector activated until forever... Well, at |
| 710 | least until all symbols have been discarded anyway (see |
| 711 | above). */ |
| 712 | if (objfile == symfile_objfile) |
| 713 | { |
| 714 | gdb_assert (proc_handle.pid == 0); |
| 715 | keep_thread_db = 1; |
| 716 | } |
| 717 | |
| 718 | /* We can only poke around if there actually is a child process. |
| 719 | If there is no child process alive, postpone the steps below |
| 720 | until one has been created. */ |
| 721 | if (proc_handle.pid != 0) |
| 722 | { |
| 723 | enable_thread_event_reporting (); |
| 724 | thread_db_find_new_threads (); |
| 725 | } |
| 726 | break; |
| 727 | |
| 728 | default: |
| 729 | warning ("Cannot initialize thread debugging library: %s", |
| 730 | thread_db_err_str (err)); |
| 731 | break; |
| 732 | } |
| 733 | |
| 734 | quit: |
| 735 | if (target_new_objfile_chain) |
| 736 | target_new_objfile_chain (objfile); |
| 737 | } |
| 738 | |
| 739 | /* Attach to a new thread. This function is called when we receive a |
| 740 | TD_CREATE event or when we iterate over all threads and find one |
| 741 | that wasn't already in our list. */ |
| 742 | |
| 743 | static void |
| 744 | attach_thread (ptid_t ptid, const td_thrhandle_t *th_p, |
| 745 | const td_thrinfo_t *ti_p, int verbose) |
| 746 | { |
| 747 | struct thread_info *tp; |
| 748 | td_err_e err; |
| 749 | |
| 750 | /* If we're being called after a TD_CREATE event, we may already |
| 751 | know about this thread. There are two ways this can happen. We |
| 752 | may have iterated over all threads between the thread creation |
| 753 | and the TD_CREATE event, for instance when the user has issued |
| 754 | the `info threads' command before the SIGTRAP for hitting the |
| 755 | thread creation breakpoint was reported. Alternatively, the |
| 756 | thread may have exited and a new one been created with the same |
| 757 | thread ID. In the first case we don't need to do anything; in |
| 758 | the second case we should discard information about the dead |
| 759 | thread and attach to the new one. */ |
| 760 | if (in_thread_list (ptid)) |
| 761 | { |
| 762 | tp = find_thread_pid (ptid); |
| 763 | gdb_assert (tp != NULL); |
| 764 | |
| 765 | if (!tp->private->dying) |
| 766 | return; |
| 767 | |
| 768 | delete_thread (ptid); |
| 769 | } |
| 770 | |
| 771 | check_thread_signals (); |
| 772 | |
| 773 | /* Add the thread to GDB's thread list. */ |
| 774 | tp = add_thread (ptid); |
| 775 | tp->private = xmalloc (sizeof (struct private_thread_info)); |
| 776 | memset (tp->private, 0, sizeof (struct private_thread_info)); |
| 777 | |
| 778 | if (verbose) |
| 779 | printf_unfiltered ("[New %s]\n", target_pid_to_str (ptid)); |
| 780 | |
| 781 | if (ti_p->ti_state == TD_THR_UNKNOWN || ti_p->ti_state == TD_THR_ZOMBIE) |
| 782 | return; /* A zombie thread -- do not attach. */ |
| 783 | |
| 784 | /* Under GNU/Linux, we have to attach to each and every thread. */ |
| 785 | #ifdef ATTACH_LWP |
| 786 | ATTACH_LWP (BUILD_LWP (ti_p->ti_lid, GET_PID (ptid)), 0); |
| 787 | #endif |
| 788 | |
| 789 | /* Enable thread event reporting for this thread. */ |
| 790 | err = td_thr_event_enable_p (th_p, 1); |
| 791 | if (err != TD_OK) |
| 792 | error ("Cannot enable thread event reporting for %s: %s", |
| 793 | target_pid_to_str (ptid), thread_db_err_str (err)); |
| 794 | } |
| 795 | |
| 796 | static void |
| 797 | thread_db_attach (char *args, int from_tty) |
| 798 | { |
| 799 | target_beneath->to_attach (args, from_tty); |
| 800 | |
| 801 | /* Destroy thread info; it's no longer valid. */ |
| 802 | init_thread_list (); |
| 803 | |
| 804 | /* The child process is now the actual multi-threaded |
| 805 | program. Snatch its process ID... */ |
| 806 | proc_handle.pid = GET_PID (inferior_ptid); |
| 807 | |
| 808 | /* ...and perform the remaining initialization steps. */ |
| 809 | enable_thread_event_reporting (); |
| 810 | thread_db_find_new_threads (); |
| 811 | } |
| 812 | |
| 813 | static void |
| 814 | detach_thread (ptid_t ptid, int verbose) |
| 815 | { |
| 816 | struct thread_info *thread_info; |
| 817 | |
| 818 | if (verbose) |
| 819 | printf_unfiltered ("[%s exited]\n", target_pid_to_str (ptid)); |
| 820 | |
| 821 | /* Don't delete the thread now, because it still reports as active |
| 822 | until it has executed a few instructions after the event |
| 823 | breakpoint - if we deleted it now, "info threads" would cause us |
| 824 | to re-attach to it. Just mark it as having had a TD_DEATH |
| 825 | event. This means that we won't delete it from our thread list |
| 826 | until we notice that it's dead (via prune_threads), or until |
| 827 | something re-uses its thread ID. */ |
| 828 | thread_info = find_thread_pid (ptid); |
| 829 | gdb_assert (thread_info != NULL); |
| 830 | thread_info->private->dying = 1; |
| 831 | } |
| 832 | |
| 833 | static void |
| 834 | thread_db_detach (char *args, int from_tty) |
| 835 | { |
| 836 | disable_thread_event_reporting (); |
| 837 | |
| 838 | /* There's no need to save & restore inferior_ptid here, since the |
| 839 | inferior is supposed to be survive this function call. */ |
| 840 | inferior_ptid = lwp_from_thread (inferior_ptid); |
| 841 | |
| 842 | /* Forget about the child's process ID. We shouldn't need it |
| 843 | anymore. */ |
| 844 | proc_handle.pid = 0; |
| 845 | |
| 846 | target_beneath->to_detach (args, from_tty); |
| 847 | } |
| 848 | |
| 849 | static int |
| 850 | clear_lwpid_callback (struct thread_info *thread, void *dummy) |
| 851 | { |
| 852 | /* If we know that our thread implementation is 1-to-1, we could save |
| 853 | a certain amount of information; it's not clear how much, so we |
| 854 | are always conservative. */ |
| 855 | |
| 856 | thread->private->th_valid = 0; |
| 857 | thread->private->ti_valid = 0; |
| 858 | |
| 859 | return 0; |
| 860 | } |
| 861 | |
| 862 | static void |
| 863 | thread_db_resume (ptid_t ptid, int step, enum target_signal signo) |
| 864 | { |
| 865 | struct cleanup *old_chain = save_inferior_ptid (); |
| 866 | |
| 867 | if (GET_PID (ptid) == -1) |
| 868 | inferior_ptid = lwp_from_thread (inferior_ptid); |
| 869 | else if (is_thread (ptid)) |
| 870 | ptid = lwp_from_thread (ptid); |
| 871 | |
| 872 | /* Clear cached data which may not be valid after the resume. */ |
| 873 | iterate_over_threads (clear_lwpid_callback, NULL); |
| 874 | |
| 875 | target_beneath->to_resume (ptid, step, signo); |
| 876 | |
| 877 | do_cleanups (old_chain); |
| 878 | } |
| 879 | |
| 880 | /* Check if PID is currently stopped at the location of a thread event |
| 881 | breakpoint location. If it is, read the event message and act upon |
| 882 | the event. */ |
| 883 | |
| 884 | static void |
| 885 | check_event (ptid_t ptid) |
| 886 | { |
| 887 | td_event_msg_t msg; |
| 888 | td_thrinfo_t ti; |
| 889 | td_err_e err; |
| 890 | CORE_ADDR stop_pc; |
| 891 | int loop = 0; |
| 892 | |
| 893 | /* Bail out early if we're not at a thread event breakpoint. */ |
| 894 | stop_pc = read_pc_pid (ptid) - DECR_PC_AFTER_BREAK; |
| 895 | if (stop_pc != td_create_bp_addr && stop_pc != td_death_bp_addr) |
| 896 | return; |
| 897 | |
| 898 | /* If we are at a create breakpoint, we do not know what new lwp |
| 899 | was created and cannot specifically locate the event message for it. |
| 900 | We have to call td_ta_event_getmsg() to get |
| 901 | the latest message. Since we have no way of correlating whether |
| 902 | the event message we get back corresponds to our breakpoint, we must |
| 903 | loop and read all event messages, processing them appropriately. |
| 904 | This guarantees we will process the correct message before continuing |
| 905 | from the breakpoint. |
| 906 | |
| 907 | Currently, death events are not enabled. If they are enabled, |
| 908 | the death event can use the td_thr_event_getmsg() interface to |
| 909 | get the message specifically for that lwp and avoid looping |
| 910 | below. */ |
| 911 | |
| 912 | loop = 1; |
| 913 | |
| 914 | do |
| 915 | { |
| 916 | err = td_ta_event_getmsg_p (thread_agent, &msg); |
| 917 | if (err != TD_OK) |
| 918 | { |
| 919 | if (err == TD_NOMSG) |
| 920 | return; |
| 921 | |
| 922 | error ("Cannot get thread event message: %s", |
| 923 | thread_db_err_str (err)); |
| 924 | } |
| 925 | |
| 926 | err = td_thr_get_info_p (msg.th_p, &ti); |
| 927 | if (err != TD_OK) |
| 928 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 929 | |
| 930 | ptid = BUILD_THREAD (ti.ti_tid, GET_PID (ptid)); |
| 931 | |
| 932 | switch (msg.event) |
| 933 | { |
| 934 | case TD_CREATE: |
| 935 | /* Call attach_thread whether or not we already know about a |
| 936 | thread with this thread ID. */ |
| 937 | attach_thread (ptid, msg.th_p, &ti, 1); |
| 938 | |
| 939 | break; |
| 940 | |
| 941 | case TD_DEATH: |
| 942 | |
| 943 | if (!in_thread_list (ptid)) |
| 944 | error ("Spurious thread death event."); |
| 945 | |
| 946 | detach_thread (ptid, 1); |
| 947 | |
| 948 | break; |
| 949 | |
| 950 | default: |
| 951 | error ("Spurious thread event."); |
| 952 | } |
| 953 | } |
| 954 | while (loop); |
| 955 | } |
| 956 | |
| 957 | static ptid_t |
| 958 | thread_db_wait (ptid_t ptid, struct target_waitstatus *ourstatus) |
| 959 | { |
| 960 | extern ptid_t trap_ptid; |
| 961 | |
| 962 | if (GET_PID (ptid) != -1 && is_thread (ptid)) |
| 963 | ptid = lwp_from_thread (ptid); |
| 964 | |
| 965 | ptid = target_beneath->to_wait (ptid, ourstatus); |
| 966 | |
| 967 | if (proc_handle.pid == 0) |
| 968 | /* The current child process isn't the actual multi-threaded |
| 969 | program yet, so don't try to do any special thread-specific |
| 970 | post-processing and bail out early. */ |
| 971 | return ptid; |
| 972 | |
| 973 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
| 974 | return pid_to_ptid (-1); |
| 975 | |
| 976 | if (ourstatus->kind == TARGET_WAITKIND_STOPPED |
| 977 | && ourstatus->value.sig == TARGET_SIGNAL_TRAP) |
| 978 | /* Check for a thread event. */ |
| 979 | check_event (ptid); |
| 980 | |
| 981 | if (!ptid_equal (trap_ptid, null_ptid)) |
| 982 | trap_ptid = thread_from_lwp (trap_ptid); |
| 983 | |
| 984 | /* Change the ptid back into the higher level PID + TID format. |
| 985 | If the thread is dead and no longer on the thread list, we will |
| 986 | get back a dead ptid. This can occur if the thread death event |
| 987 | gets postponed by other simultaneous events. In such a case, |
| 988 | we want to just ignore the event and continue on. */ |
| 989 | ptid = thread_from_lwp (ptid); |
| 990 | if (GET_PID (ptid) == -1) |
| 991 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; |
| 992 | |
| 993 | return ptid; |
| 994 | } |
| 995 | |
| 996 | static int |
| 997 | thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write, |
| 998 | struct mem_attrib *attrib, struct target_ops *target) |
| 999 | { |
| 1000 | struct cleanup *old_chain = save_inferior_ptid (); |
| 1001 | int xfer; |
| 1002 | |
| 1003 | if (is_thread (inferior_ptid)) |
| 1004 | { |
| 1005 | /* FIXME: This seems to be necessary to make sure breakpoints |
| 1006 | are removed. */ |
| 1007 | if (!target_thread_alive (inferior_ptid)) |
| 1008 | inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid)); |
| 1009 | else |
| 1010 | inferior_ptid = lwp_from_thread (inferior_ptid); |
| 1011 | } |
| 1012 | |
| 1013 | xfer = |
| 1014 | target_beneath->to_xfer_memory (memaddr, myaddr, len, write, attrib, |
| 1015 | target); |
| 1016 | |
| 1017 | do_cleanups (old_chain); |
| 1018 | return xfer; |
| 1019 | } |
| 1020 | |
| 1021 | static void |
| 1022 | thread_db_fetch_registers (int regno) |
| 1023 | { |
| 1024 | struct thread_info *thread_info; |
| 1025 | prgregset_t gregset; |
| 1026 | gdb_prfpregset_t fpregset; |
| 1027 | td_err_e err; |
| 1028 | |
| 1029 | if (!is_thread (inferior_ptid)) |
| 1030 | { |
| 1031 | /* Pass the request to the target beneath us. */ |
| 1032 | target_beneath->to_fetch_registers (regno); |
| 1033 | return; |
| 1034 | } |
| 1035 | |
| 1036 | thread_info = find_thread_pid (inferior_ptid); |
| 1037 | thread_db_map_id2thr (thread_info, 1); |
| 1038 | |
| 1039 | err = td_thr_getgregs_p (&thread_info->private->th, gregset); |
| 1040 | if (err != TD_OK) |
| 1041 | error ("Cannot fetch general-purpose registers for thread %ld: %s", |
| 1042 | (long) GET_THREAD (inferior_ptid), thread_db_err_str (err)); |
| 1043 | |
| 1044 | err = td_thr_getfpregs_p (&thread_info->private->th, &fpregset); |
| 1045 | if (err != TD_OK) |
| 1046 | error ("Cannot get floating-point registers for thread %ld: %s", |
| 1047 | (long) GET_THREAD (inferior_ptid), thread_db_err_str (err)); |
| 1048 | |
| 1049 | /* Note that we must call supply_gregset after calling the thread_db |
| 1050 | routines because the thread_db routines call ps_lgetgregs and |
| 1051 | friends which clobber GDB's register cache. */ |
| 1052 | supply_gregset ((gdb_gregset_t *) gregset); |
| 1053 | supply_fpregset (&fpregset); |
| 1054 | } |
| 1055 | |
| 1056 | static void |
| 1057 | thread_db_store_registers (int regno) |
| 1058 | { |
| 1059 | prgregset_t gregset; |
| 1060 | gdb_prfpregset_t fpregset; |
| 1061 | td_err_e err; |
| 1062 | struct thread_info *thread_info; |
| 1063 | |
| 1064 | if (!is_thread (inferior_ptid)) |
| 1065 | { |
| 1066 | /* Pass the request to the target beneath us. */ |
| 1067 | target_beneath->to_store_registers (regno); |
| 1068 | return; |
| 1069 | } |
| 1070 | |
| 1071 | thread_info = find_thread_pid (inferior_ptid); |
| 1072 | thread_db_map_id2thr (thread_info, 1); |
| 1073 | |
| 1074 | if (regno != -1) |
| 1075 | { |
| 1076 | char raw[MAX_REGISTER_SIZE]; |
| 1077 | |
| 1078 | deprecated_read_register_gen (regno, raw); |
| 1079 | thread_db_fetch_registers (-1); |
| 1080 | supply_register (regno, raw); |
| 1081 | } |
| 1082 | |
| 1083 | fill_gregset ((gdb_gregset_t *) gregset, -1); |
| 1084 | fill_fpregset (&fpregset, -1); |
| 1085 | |
| 1086 | err = td_thr_setgregs_p (&thread_info->private->th, gregset); |
| 1087 | if (err != TD_OK) |
| 1088 | error ("Cannot store general-purpose registers for thread %ld: %s", |
| 1089 | (long) GET_THREAD (inferior_ptid), thread_db_err_str (err)); |
| 1090 | err = td_thr_setfpregs_p (&thread_info->private->th, &fpregset); |
| 1091 | if (err != TD_OK) |
| 1092 | error ("Cannot store floating-point registers for thread %ld: %s", |
| 1093 | (long) GET_THREAD (inferior_ptid), thread_db_err_str (err)); |
| 1094 | } |
| 1095 | |
| 1096 | static void |
| 1097 | thread_db_kill (void) |
| 1098 | { |
| 1099 | /* There's no need to save & restore inferior_ptid here, since the |
| 1100 | inferior isn't supposed to survive this function call. */ |
| 1101 | inferior_ptid = lwp_from_thread (inferior_ptid); |
| 1102 | target_beneath->to_kill (); |
| 1103 | } |
| 1104 | |
| 1105 | static void |
| 1106 | thread_db_create_inferior (char *exec_file, char *allargs, char **env, |
| 1107 | int from_tty) |
| 1108 | { |
| 1109 | if (!keep_thread_db) |
| 1110 | { |
| 1111 | unpush_target (&thread_db_ops); |
| 1112 | using_thread_db = 0; |
| 1113 | } |
| 1114 | |
| 1115 | target_beneath->to_create_inferior (exec_file, allargs, env, from_tty); |
| 1116 | } |
| 1117 | |
| 1118 | static void |
| 1119 | thread_db_post_startup_inferior (ptid_t ptid) |
| 1120 | { |
| 1121 | if (proc_handle.pid == 0) |
| 1122 | { |
| 1123 | /* The child process is now the actual multi-threaded |
| 1124 | program. Snatch its process ID... */ |
| 1125 | proc_handle.pid = GET_PID (ptid); |
| 1126 | |
| 1127 | /* ...and perform the remaining initialization steps. */ |
| 1128 | enable_thread_event_reporting (); |
| 1129 | thread_db_find_new_threads (); |
| 1130 | } |
| 1131 | } |
| 1132 | |
| 1133 | static void |
| 1134 | thread_db_mourn_inferior (void) |
| 1135 | { |
| 1136 | remove_thread_event_breakpoints (); |
| 1137 | |
| 1138 | /* Forget about the child's process ID. We shouldn't need it |
| 1139 | anymore. */ |
| 1140 | proc_handle.pid = 0; |
| 1141 | |
| 1142 | target_beneath->to_mourn_inferior (); |
| 1143 | |
| 1144 | /* Detach thread_db target ops if not dealing with a statically |
| 1145 | linked threaded program. This allows a corefile to be debugged |
| 1146 | after finishing debugging of a threaded program. At present, |
| 1147 | debugging a statically-linked threaded program is broken, but |
| 1148 | the check is added below in the event that it is fixed in the |
| 1149 | future. */ |
| 1150 | if (!keep_thread_db) |
| 1151 | { |
| 1152 | unpush_target (&thread_db_ops); |
| 1153 | using_thread_db = 0; |
| 1154 | } |
| 1155 | } |
| 1156 | |
| 1157 | static int |
| 1158 | thread_db_thread_alive (ptid_t ptid) |
| 1159 | { |
| 1160 | td_thrhandle_t th; |
| 1161 | td_err_e err; |
| 1162 | |
| 1163 | if (is_thread (ptid)) |
| 1164 | { |
| 1165 | struct thread_info *thread_info; |
| 1166 | thread_info = find_thread_pid (ptid); |
| 1167 | |
| 1168 | thread_db_map_id2thr (thread_info, 0); |
| 1169 | if (!thread_info->private->th_valid) |
| 1170 | return 0; |
| 1171 | |
| 1172 | err = td_thr_validate_p (&thread_info->private->th); |
| 1173 | if (err != TD_OK) |
| 1174 | return 0; |
| 1175 | |
| 1176 | if (!thread_info->private->ti_valid) |
| 1177 | { |
| 1178 | err = |
| 1179 | td_thr_get_info_p (&thread_info->private->th, |
| 1180 | &thread_info->private->ti); |
| 1181 | if (err != TD_OK) |
| 1182 | return 0; |
| 1183 | thread_info->private->ti_valid = 1; |
| 1184 | } |
| 1185 | |
| 1186 | if (thread_info->private->ti.ti_state == TD_THR_UNKNOWN |
| 1187 | || thread_info->private->ti.ti_state == TD_THR_ZOMBIE) |
| 1188 | return 0; /* A zombie thread. */ |
| 1189 | |
| 1190 | return 1; |
| 1191 | } |
| 1192 | |
| 1193 | if (target_beneath->to_thread_alive) |
| 1194 | return target_beneath->to_thread_alive (ptid); |
| 1195 | |
| 1196 | return 0; |
| 1197 | } |
| 1198 | |
| 1199 | static int |
| 1200 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) |
| 1201 | { |
| 1202 | td_thrinfo_t ti; |
| 1203 | td_err_e err; |
| 1204 | ptid_t ptid; |
| 1205 | |
| 1206 | err = td_thr_get_info_p (th_p, &ti); |
| 1207 | if (err != TD_OK) |
| 1208 | error ("find_new_threads_callback: cannot get thread info: %s", |
| 1209 | thread_db_err_str (err)); |
| 1210 | |
| 1211 | if (ti.ti_state == TD_THR_UNKNOWN || ti.ti_state == TD_THR_ZOMBIE) |
| 1212 | return 0; /* A zombie -- ignore. */ |
| 1213 | |
| 1214 | ptid = BUILD_THREAD (ti.ti_tid, GET_PID (inferior_ptid)); |
| 1215 | |
| 1216 | if (!in_thread_list (ptid)) |
| 1217 | attach_thread (ptid, th_p, &ti, 1); |
| 1218 | |
| 1219 | return 0; |
| 1220 | } |
| 1221 | |
| 1222 | static void |
| 1223 | thread_db_find_new_threads (void) |
| 1224 | { |
| 1225 | td_err_e err; |
| 1226 | |
| 1227 | /* Iterate over all user-space threads to discover new threads. */ |
| 1228 | err = td_ta_thr_iter_p (thread_agent, find_new_threads_callback, NULL, |
| 1229 | TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY, |
| 1230 | TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS); |
| 1231 | if (err != TD_OK) |
| 1232 | error ("Cannot find new threads: %s", thread_db_err_str (err)); |
| 1233 | } |
| 1234 | |
| 1235 | static char * |
| 1236 | thread_db_pid_to_str (ptid_t ptid) |
| 1237 | { |
| 1238 | if (is_thread (ptid)) |
| 1239 | { |
| 1240 | static char buf[64]; |
| 1241 | td_thrinfo_t *ti_p; |
| 1242 | td_err_e err; |
| 1243 | struct thread_info *thread_info; |
| 1244 | |
| 1245 | thread_info = find_thread_pid (ptid); |
| 1246 | thread_db_map_id2thr (thread_info, 0); |
| 1247 | if (!thread_info->private->th_valid) |
| 1248 | { |
| 1249 | snprintf (buf, sizeof (buf), "Thread %ld (Missing)", |
| 1250 | GET_THREAD (ptid)); |
| 1251 | return buf; |
| 1252 | } |
| 1253 | |
| 1254 | ti_p = thread_db_get_info (thread_info); |
| 1255 | |
| 1256 | if (ti_p->ti_state == TD_THR_ACTIVE && ti_p->ti_lid != 0) |
| 1257 | { |
| 1258 | snprintf (buf, sizeof (buf), "Thread %ld (LWP %d)", |
| 1259 | (long) ti_p->ti_tid, ti_p->ti_lid); |
| 1260 | } |
| 1261 | else |
| 1262 | { |
| 1263 | snprintf (buf, sizeof (buf), "Thread %ld (%s)", |
| 1264 | (long) ti_p->ti_tid, |
| 1265 | thread_db_state_str (ti_p->ti_state)); |
| 1266 | } |
| 1267 | |
| 1268 | return buf; |
| 1269 | } |
| 1270 | |
| 1271 | if (target_beneath->to_pid_to_str (ptid)) |
| 1272 | return target_beneath->to_pid_to_str (ptid); |
| 1273 | |
| 1274 | return normal_pid_to_str (ptid); |
| 1275 | } |
| 1276 | |
| 1277 | /* Get the address of the thread local variable in OBJFILE which is |
| 1278 | stored at OFFSET within the thread local storage for thread PTID. */ |
| 1279 | |
| 1280 | static CORE_ADDR |
| 1281 | thread_db_get_thread_local_address (ptid_t ptid, struct objfile *objfile, |
| 1282 | CORE_ADDR offset) |
| 1283 | { |
| 1284 | if (is_thread (ptid)) |
| 1285 | { |
| 1286 | int objfile_is_library = (objfile->flags & OBJF_SHARED); |
| 1287 | td_err_e err; |
| 1288 | void *address; |
| 1289 | CORE_ADDR lm; |
| 1290 | struct thread_info *thread_info; |
| 1291 | |
| 1292 | /* glibc doesn't provide the needed interface. */ |
| 1293 | if (!td_thr_tls_get_addr_p) |
| 1294 | error ("Cannot find thread-local variables in this thread library."); |
| 1295 | |
| 1296 | /* Get the address of the link map for this objfile. */ |
| 1297 | lm = svr4_fetch_objfile_link_map (objfile); |
| 1298 | |
| 1299 | /* Whoops, we couldn't find one. Bail out. */ |
| 1300 | if (!lm) |
| 1301 | { |
| 1302 | if (objfile_is_library) |
| 1303 | error ("Cannot find shared library `%s' link_map in dynamic" |
| 1304 | " linker's module list", objfile->name); |
| 1305 | else |
| 1306 | error ("Cannot find executable file `%s' link_map in dynamic" |
| 1307 | " linker's module list", objfile->name); |
| 1308 | } |
| 1309 | |
| 1310 | /* Get info about the thread. */ |
| 1311 | thread_info = find_thread_pid (ptid); |
| 1312 | thread_db_map_id2thr (thread_info, 1); |
| 1313 | |
| 1314 | /* Finally, get the address of the variable. */ |
| 1315 | err = td_thr_tls_get_addr_p (&thread_info->private->th, (void *) lm, |
| 1316 | offset, &address); |
| 1317 | |
| 1318 | #ifdef THREAD_DB_HAS_TD_NOTALLOC |
| 1319 | /* The memory hasn't been allocated, yet. */ |
| 1320 | if (err == TD_NOTALLOC) |
| 1321 | { |
| 1322 | /* Now, if libthread_db provided the initialization image's |
| 1323 | address, we *could* try to build a non-lvalue value from |
| 1324 | the initialization image. */ |
| 1325 | if (objfile_is_library) |
| 1326 | error ("The inferior has not yet allocated storage for" |
| 1327 | " thread-local variables in\n" |
| 1328 | "the shared library `%s'\n" |
| 1329 | "for the thread %ld", |
| 1330 | objfile->name, (long) GET_THREAD (ptid)); |
| 1331 | else |
| 1332 | error ("The inferior has not yet allocated storage for" |
| 1333 | " thread-local variables in\n" |
| 1334 | "the executable `%s'\n" |
| 1335 | "for the thread %ld", |
| 1336 | objfile->name, (long) GET_THREAD (ptid)); |
| 1337 | } |
| 1338 | #endif |
| 1339 | |
| 1340 | /* Something else went wrong. */ |
| 1341 | if (err != TD_OK) |
| 1342 | { |
| 1343 | if (objfile_is_library) |
| 1344 | error ("Cannot find thread-local storage for thread %ld, " |
| 1345 | "shared library %s:\n%s", |
| 1346 | (long) GET_THREAD (ptid), |
| 1347 | objfile->name, thread_db_err_str (err)); |
| 1348 | else |
| 1349 | error ("Cannot find thread-local storage for thread %ld, " |
| 1350 | "executable file %s:\n%s", |
| 1351 | (long) GET_THREAD (ptid), |
| 1352 | objfile->name, thread_db_err_str (err)); |
| 1353 | } |
| 1354 | |
| 1355 | /* Cast assuming host == target. Joy. */ |
| 1356 | return (CORE_ADDR) address; |
| 1357 | } |
| 1358 | |
| 1359 | if (target_beneath->to_get_thread_local_address) |
| 1360 | return target_beneath->to_get_thread_local_address (ptid, objfile, |
| 1361 | offset); |
| 1362 | |
| 1363 | error ("Cannot find thread-local values on this target."); |
| 1364 | } |
| 1365 | |
| 1366 | static void |
| 1367 | init_thread_db_ops (void) |
| 1368 | { |
| 1369 | thread_db_ops.to_shortname = "multi-thread"; |
| 1370 | thread_db_ops.to_longname = "multi-threaded child process."; |
| 1371 | thread_db_ops.to_doc = "Threads and pthreads support."; |
| 1372 | thread_db_ops.to_attach = thread_db_attach; |
| 1373 | thread_db_ops.to_detach = thread_db_detach; |
| 1374 | thread_db_ops.to_resume = thread_db_resume; |
| 1375 | thread_db_ops.to_wait = thread_db_wait; |
| 1376 | thread_db_ops.to_fetch_registers = thread_db_fetch_registers; |
| 1377 | thread_db_ops.to_store_registers = thread_db_store_registers; |
| 1378 | thread_db_ops.to_xfer_memory = thread_db_xfer_memory; |
| 1379 | thread_db_ops.to_kill = thread_db_kill; |
| 1380 | thread_db_ops.to_create_inferior = thread_db_create_inferior; |
| 1381 | thread_db_ops.to_post_startup_inferior = thread_db_post_startup_inferior; |
| 1382 | thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior; |
| 1383 | thread_db_ops.to_thread_alive = thread_db_thread_alive; |
| 1384 | thread_db_ops.to_find_new_threads = thread_db_find_new_threads; |
| 1385 | thread_db_ops.to_pid_to_str = thread_db_pid_to_str; |
| 1386 | thread_db_ops.to_stratum = thread_stratum; |
| 1387 | thread_db_ops.to_has_thread_control = tc_schedlock; |
| 1388 | thread_db_ops.to_get_thread_local_address |
| 1389 | = thread_db_get_thread_local_address; |
| 1390 | thread_db_ops.to_magic = OPS_MAGIC; |
| 1391 | } |
| 1392 | |
| 1393 | void |
| 1394 | _initialize_thread_db (void) |
| 1395 | { |
| 1396 | /* Only initialize the module if we can load libthread_db. */ |
| 1397 | if (thread_db_load ()) |
| 1398 | { |
| 1399 | init_thread_db_ops (); |
| 1400 | add_target (&thread_db_ops); |
| 1401 | |
| 1402 | /* Add ourselves to objfile event chain. */ |
| 1403 | target_new_objfile_chain = deprecated_target_new_objfile_hook; |
| 1404 | deprecated_target_new_objfile_hook = thread_db_new_objfile; |
| 1405 | } |
| 1406 | } |