| 1 | /* libthread_db assisted debugging support, generic parts. |
| 2 | Copyright 1999, 2000, 2001 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | |
| 23 | #include "gdb_assert.h" |
| 24 | #include <dlfcn.h> |
| 25 | #include "gdb_proc_service.h" |
| 26 | #include "gdb_thread_db.h" |
| 27 | |
| 28 | #include "bfd.h" |
| 29 | #include "gdbthread.h" |
| 30 | #include "inferior.h" |
| 31 | #include "symfile.h" |
| 32 | #include "objfiles.h" |
| 33 | #include "target.h" |
| 34 | #include "regcache.h" |
| 35 | |
| 36 | #ifndef LIBTHREAD_DB_SO |
| 37 | #define LIBTHREAD_DB_SO "libthread_db.so.1" |
| 38 | #endif |
| 39 | |
| 40 | /* If we're running on Linux, we must explicitly attach to any new threads. */ |
| 41 | |
| 42 | /* FIXME: There is certainly some room for improvements: |
| 43 | - Cache LWP ids. |
| 44 | - Bypass libthread_db when fetching or storing registers for |
| 45 | threads bound to a LWP. */ |
| 46 | |
| 47 | /* This module's target vector. */ |
| 48 | static struct target_ops thread_db_ops; |
| 49 | |
| 50 | /* The target vector that we call for things this module can't handle. */ |
| 51 | static struct target_ops *target_beneath; |
| 52 | |
| 53 | /* Pointer to the next function on the objfile event chain. */ |
| 54 | static void (*target_new_objfile_chain) (struct objfile *objfile); |
| 55 | |
| 56 | /* Non-zero if we're using this module's target vector. */ |
| 57 | static int using_thread_db; |
| 58 | |
| 59 | /* Non-zero if we musn't deactivate this module's target vector. */ |
| 60 | static int keep_thread_db; |
| 61 | |
| 62 | /* Non-zero if we have determined the signals used by the threads |
| 63 | library. */ |
| 64 | static int thread_signals; |
| 65 | static sigset_t thread_stop_set; |
| 66 | static sigset_t thread_print_set; |
| 67 | |
| 68 | /* Structure that identifies the child process for the |
| 69 | <proc_service.h> interface. */ |
| 70 | static struct ps_prochandle proc_handle; |
| 71 | |
| 72 | /* Connection to the libthread_db library. */ |
| 73 | static td_thragent_t *thread_agent; |
| 74 | |
| 75 | /* Pointers to the libthread_db functions. */ |
| 76 | |
| 77 | static td_err_e (*td_init_p) (void); |
| 78 | |
| 79 | static td_err_e (*td_ta_new_p) (struct ps_prochandle *ps, td_thragent_t **ta); |
| 80 | static td_err_e (*td_ta_map_id2thr_p) (const td_thragent_t *ta, thread_t pt, |
| 81 | td_thrhandle_t *__th); |
| 82 | static td_err_e (*td_ta_map_lwp2thr_p) (const td_thragent_t *ta, lwpid_t lwpid, |
| 83 | td_thrhandle_t *th); |
| 84 | static td_err_e (*td_ta_thr_iter_p) (const td_thragent_t *ta, |
| 85 | td_thr_iter_f *callback, |
| 86 | void *cbdata_p, td_thr_state_e state, |
| 87 | int ti_pri, sigset_t *ti_sigmask_p, |
| 88 | unsigned int ti_user_flags); |
| 89 | static td_err_e (*td_ta_event_addr_p) (const td_thragent_t *ta, |
| 90 | td_event_e event, td_notify_t *ptr); |
| 91 | static td_err_e (*td_ta_set_event_p) (const td_thragent_t *ta, |
| 92 | td_thr_events_t *event); |
| 93 | static td_err_e (*td_ta_event_getmsg_p) (const td_thragent_t *ta, |
| 94 | td_event_msg_t *msg); |
| 95 | |
| 96 | static td_err_e (*td_thr_validate_p) (const td_thrhandle_t *th); |
| 97 | static td_err_e (*td_thr_get_info_p) (const td_thrhandle_t *th, |
| 98 | td_thrinfo_t *infop); |
| 99 | static td_err_e (*td_thr_getfpregs_p) (const td_thrhandle_t *th, |
| 100 | gdb_prfpregset_t *regset); |
| 101 | static td_err_e (*td_thr_getgregs_p) (const td_thrhandle_t *th, |
| 102 | prgregset_t gregs); |
| 103 | static td_err_e (*td_thr_setfpregs_p) (const td_thrhandle_t *th, |
| 104 | const gdb_prfpregset_t *fpregs); |
| 105 | static td_err_e (*td_thr_setgregs_p) (const td_thrhandle_t *th, |
| 106 | prgregset_t gregs); |
| 107 | static td_err_e (*td_thr_event_enable_p) (const td_thrhandle_t *th, int event); |
| 108 | |
| 109 | /* Location of the thread creation event breakpoint. The code at this |
| 110 | location in the child process will be called by the pthread library |
| 111 | whenever a new thread is created. By setting a special breakpoint |
| 112 | at this location, GDB can detect when a new thread is created. We |
| 113 | obtain this location via the td_ta_event_addr call. */ |
| 114 | static CORE_ADDR td_create_bp_addr; |
| 115 | |
| 116 | /* Location of the thread death event breakpoint. */ |
| 117 | static CORE_ADDR td_death_bp_addr; |
| 118 | |
| 119 | /* Prototypes for local functions. */ |
| 120 | static void thread_db_find_new_threads (void); |
| 121 | \f |
| 122 | |
| 123 | /* Building process ids. */ |
| 124 | |
| 125 | #ifndef TIDGET |
| 126 | #define TIDGET(PID) (((PID) & 0x7fffffff) >> 16) |
| 127 | #define PIDGET(PID) (((PID) & 0xffff)) |
| 128 | #define MERGEPID(PID, TID) (((PID) & 0xffff) | ((TID) << 16)) |
| 129 | #endif |
| 130 | |
| 131 | #define THREAD_FLAG 0x80000000 |
| 132 | |
| 133 | #define is_lwp(pid) (((pid) & THREAD_FLAG) == 0 && TIDGET (pid)) |
| 134 | #define is_thread(pid) ((pid) & THREAD_FLAG) |
| 135 | |
| 136 | #define GET_PID(pid) PIDGET (pid) |
| 137 | #define GET_LWP(pid) TIDGET (pid) |
| 138 | #define GET_THREAD(pid) TIDGET (pid) |
| 139 | |
| 140 | #define BUILD_LWP(tid, pid) MERGEPID (pid, tid) |
| 141 | #define BUILD_THREAD(tid, pid) (MERGEPID (pid, tid) | THREAD_FLAG) |
| 142 | \f |
| 143 | |
| 144 | struct private_thread_info |
| 145 | { |
| 146 | /* Cached LWP id. Must come first, see lin-lwp.c. */ |
| 147 | lwpid_t lwpid; |
| 148 | }; |
| 149 | |
| 150 | \f |
| 151 | /* Helper functions. */ |
| 152 | |
| 153 | static void |
| 154 | restore_inferior_pid (void *arg) |
| 155 | { |
| 156 | int *saved_pid_ptr = arg; |
| 157 | inferior_pid = *saved_pid_ptr; |
| 158 | xfree (arg); |
| 159 | } |
| 160 | |
| 161 | static struct cleanup * |
| 162 | save_inferior_pid (void) |
| 163 | { |
| 164 | int *saved_pid_ptr; |
| 165 | |
| 166 | saved_pid_ptr = xmalloc (sizeof (int)); |
| 167 | *saved_pid_ptr = inferior_pid; |
| 168 | return make_cleanup (restore_inferior_pid, saved_pid_ptr); |
| 169 | } |
| 170 | \f |
| 171 | |
| 172 | static char * |
| 173 | thread_db_err_str (td_err_e err) |
| 174 | { |
| 175 | static char buf[64]; |
| 176 | |
| 177 | switch (err) |
| 178 | { |
| 179 | case TD_OK: |
| 180 | return "generic 'call succeeded'"; |
| 181 | case TD_ERR: |
| 182 | return "generic error"; |
| 183 | case TD_NOTHR: |
| 184 | return "no thread to satisfy query"; |
| 185 | case TD_NOSV: |
| 186 | return "no sync handle to satisfy query"; |
| 187 | case TD_NOLWP: |
| 188 | return "no LWP to satisfy query"; |
| 189 | case TD_BADPH: |
| 190 | return "invalid process handle"; |
| 191 | case TD_BADTH: |
| 192 | return "invalid thread handle"; |
| 193 | case TD_BADSH: |
| 194 | return "invalid synchronization handle"; |
| 195 | case TD_BADTA: |
| 196 | return "invalid thread agent"; |
| 197 | case TD_BADKEY: |
| 198 | return "invalid key"; |
| 199 | case TD_NOMSG: |
| 200 | return "no event message for getmsg"; |
| 201 | case TD_NOFPREGS: |
| 202 | return "FPU register set not available"; |
| 203 | case TD_NOLIBTHREAD: |
| 204 | return "application not linked with libthread"; |
| 205 | case TD_NOEVENT: |
| 206 | return "requested event is not supported"; |
| 207 | case TD_NOCAPAB: |
| 208 | return "capability not available"; |
| 209 | case TD_DBERR: |
| 210 | return "debugger service failed"; |
| 211 | case TD_NOAPLIC: |
| 212 | return "operation not applicable to"; |
| 213 | case TD_NOTSD: |
| 214 | return "no thread-specific data for this thread"; |
| 215 | case TD_MALLOC: |
| 216 | return "malloc failed"; |
| 217 | case TD_PARTIALREG: |
| 218 | return "only part of register set was written/read"; |
| 219 | case TD_NOXREGS: |
| 220 | return "X register set not available for this thread"; |
| 221 | default: |
| 222 | snprintf (buf, sizeof (buf), "unknown thread_db error '%d'", err); |
| 223 | return buf; |
| 224 | } |
| 225 | } |
| 226 | |
| 227 | static char * |
| 228 | thread_db_state_str (td_thr_state_e state) |
| 229 | { |
| 230 | static char buf[64]; |
| 231 | |
| 232 | switch (state) |
| 233 | { |
| 234 | case TD_THR_STOPPED: |
| 235 | return "stopped by debugger"; |
| 236 | case TD_THR_RUN: |
| 237 | return "runnable"; |
| 238 | case TD_THR_ACTIVE: |
| 239 | return "active"; |
| 240 | case TD_THR_ZOMBIE: |
| 241 | return "zombie"; |
| 242 | case TD_THR_SLEEP: |
| 243 | return "sleeping"; |
| 244 | case TD_THR_STOPPED_ASLEEP: |
| 245 | return "stopped by debugger AND blocked"; |
| 246 | default: |
| 247 | snprintf (buf, sizeof (buf), "unknown thread_db state %d", state); |
| 248 | return buf; |
| 249 | } |
| 250 | } |
| 251 | \f |
| 252 | |
| 253 | /* Convert between user-level thread ids and LWP ids. */ |
| 254 | |
| 255 | static int |
| 256 | thread_from_lwp (int pid) |
| 257 | { |
| 258 | td_thrinfo_t ti; |
| 259 | td_thrhandle_t th; |
| 260 | td_err_e err; |
| 261 | |
| 262 | if (GET_LWP (pid) == 0) |
| 263 | pid = BUILD_LWP (pid, pid); |
| 264 | |
| 265 | gdb_assert (is_lwp (pid)); |
| 266 | |
| 267 | err = td_ta_map_lwp2thr_p (thread_agent, GET_LWP (pid), &th); |
| 268 | if (err != TD_OK) |
| 269 | error ("Cannot find user-level thread for LWP %d: %s", |
| 270 | GET_LWP (pid), thread_db_err_str (err)); |
| 271 | |
| 272 | err = td_thr_get_info_p (&th, &ti); |
| 273 | if (err != TD_OK) |
| 274 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 275 | |
| 276 | return BUILD_THREAD (ti.ti_tid, GET_PID (pid)); |
| 277 | } |
| 278 | |
| 279 | static int |
| 280 | lwp_from_thread (int pid) |
| 281 | { |
| 282 | td_thrinfo_t ti; |
| 283 | td_thrhandle_t th; |
| 284 | td_err_e err; |
| 285 | |
| 286 | if (! is_thread (pid)) |
| 287 | return pid; |
| 288 | |
| 289 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th); |
| 290 | if (err != TD_OK) |
| 291 | error ("Cannot find thread %ld: %s", |
| 292 | (long) GET_THREAD (pid), thread_db_err_str (err)); |
| 293 | |
| 294 | err = td_thr_get_info_p (&th, &ti); |
| 295 | if (err != TD_OK) |
| 296 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 297 | |
| 298 | return BUILD_LWP (ti.ti_lid, GET_PID (pid)); |
| 299 | } |
| 300 | \f |
| 301 | |
| 302 | void |
| 303 | thread_db_init (struct target_ops *target) |
| 304 | { |
| 305 | target_beneath = target; |
| 306 | } |
| 307 | |
| 308 | static int |
| 309 | thread_db_load (void) |
| 310 | { |
| 311 | void *handle; |
| 312 | td_err_e err; |
| 313 | |
| 314 | handle = dlopen (LIBTHREAD_DB_SO, RTLD_NOW); |
| 315 | if (handle == NULL) |
| 316 | return 0; |
| 317 | |
| 318 | /* Initialize pointers to the dynamic library functions we will use. |
| 319 | Essential functions first. */ |
| 320 | |
| 321 | td_init_p = dlsym (handle, "td_init"); |
| 322 | if (td_init_p == NULL) |
| 323 | return 0; |
| 324 | |
| 325 | td_ta_new_p = dlsym (handle, "td_ta_new"); |
| 326 | if (td_ta_new_p == NULL) |
| 327 | return 0; |
| 328 | |
| 329 | td_ta_map_id2thr_p = dlsym (handle, "td_ta_map_id2thr"); |
| 330 | if (td_ta_map_id2thr_p == NULL) |
| 331 | return 0; |
| 332 | |
| 333 | td_ta_map_lwp2thr_p = dlsym (handle, "td_ta_map_lwp2thr"); |
| 334 | if (td_ta_map_lwp2thr_p == NULL) |
| 335 | return 0; |
| 336 | |
| 337 | td_ta_thr_iter_p = dlsym (handle, "td_ta_thr_iter"); |
| 338 | if (td_ta_thr_iter_p == NULL) |
| 339 | return 0; |
| 340 | |
| 341 | td_thr_validate_p = dlsym (handle, "td_thr_validate"); |
| 342 | if (td_thr_validate_p == NULL) |
| 343 | return 0; |
| 344 | |
| 345 | td_thr_get_info_p = dlsym (handle, "td_thr_get_info"); |
| 346 | if (td_thr_get_info_p == NULL) |
| 347 | return 0; |
| 348 | |
| 349 | td_thr_getfpregs_p = dlsym (handle, "td_thr_getfpregs"); |
| 350 | if (td_thr_getfpregs_p == NULL) |
| 351 | return 0; |
| 352 | |
| 353 | td_thr_getgregs_p = dlsym (handle, "td_thr_getgregs"); |
| 354 | if (td_thr_getgregs_p == NULL) |
| 355 | return 0; |
| 356 | |
| 357 | td_thr_setfpregs_p = dlsym (handle, "td_thr_setfpregs"); |
| 358 | if (td_thr_setfpregs_p == NULL) |
| 359 | return 0; |
| 360 | |
| 361 | td_thr_setgregs_p = dlsym (handle, "td_thr_setgregs"); |
| 362 | if (td_thr_setgregs_p == NULL) |
| 363 | return 0; |
| 364 | |
| 365 | /* Initialize the library. */ |
| 366 | err = td_init_p (); |
| 367 | if (err != TD_OK) |
| 368 | { |
| 369 | warning ("Cannot initialize libthread_db: %s", thread_db_err_str (err)); |
| 370 | return 0; |
| 371 | } |
| 372 | |
| 373 | /* These are not essential. */ |
| 374 | td_ta_event_addr_p = dlsym (handle, "td_ta_event_addr"); |
| 375 | td_ta_set_event_p = dlsym (handle, "td_ta_set_event"); |
| 376 | td_ta_event_getmsg_p = dlsym (handle, "td_ta_event_getmsg"); |
| 377 | td_thr_event_enable_p = dlsym (handle, "td_thr_event_enable"); |
| 378 | |
| 379 | return 1; |
| 380 | } |
| 381 | |
| 382 | static void |
| 383 | enable_thread_event_reporting (void) |
| 384 | { |
| 385 | td_thr_events_t events; |
| 386 | td_notify_t notify; |
| 387 | td_err_e err; |
| 388 | |
| 389 | /* We cannot use the thread event reporting facility if these |
| 390 | functions aren't available. */ |
| 391 | if (td_ta_event_addr_p == NULL || td_ta_set_event_p == NULL |
| 392 | || td_ta_event_getmsg_p == NULL || td_thr_event_enable_p == NULL) |
| 393 | return; |
| 394 | |
| 395 | /* Set the process wide mask saying which events we're interested in. */ |
| 396 | td_event_emptyset (&events); |
| 397 | td_event_addset (&events, TD_CREATE); |
| 398 | #if 0 |
| 399 | /* FIXME: kettenis/2000-04-23: The event reporting facility is |
| 400 | broken for TD_DEATH events in glibc 2.1.3, so don't enable it for |
| 401 | now. */ |
| 402 | td_event_addset (&events, TD_DEATH); |
| 403 | #endif |
| 404 | |
| 405 | err = td_ta_set_event_p (thread_agent, &events); |
| 406 | if (err != TD_OK) |
| 407 | { |
| 408 | warning ("Unable to set global thread event mask: %s", |
| 409 | thread_db_err_str (err)); |
| 410 | return; |
| 411 | } |
| 412 | |
| 413 | /* Delete previous thread event breakpoints, if any. */ |
| 414 | remove_thread_event_breakpoints (); |
| 415 | |
| 416 | /* Get address for thread creation breakpoint. */ |
| 417 | err = td_ta_event_addr_p (thread_agent, TD_CREATE, ¬ify); |
| 418 | if (err != TD_OK) |
| 419 | { |
| 420 | warning ("Unable to get location for thread creation breakpoint: %s", |
| 421 | thread_db_err_str (err)); |
| 422 | return; |
| 423 | } |
| 424 | |
| 425 | /* Set up the breakpoint. */ |
| 426 | td_create_bp_addr = (CORE_ADDR) notify.u.bptaddr; |
| 427 | create_thread_event_breakpoint (td_create_bp_addr); |
| 428 | |
| 429 | /* Get address for thread death breakpoint. */ |
| 430 | err = td_ta_event_addr_p (thread_agent, TD_DEATH, ¬ify); |
| 431 | if (err != TD_OK) |
| 432 | { |
| 433 | warning ("Unable to get location for thread creation breakpoint: %s", |
| 434 | thread_db_err_str (err)); |
| 435 | return; |
| 436 | } |
| 437 | |
| 438 | /* Set up the breakpoint. */ |
| 439 | td_death_bp_addr = (CORE_ADDR) notify.u.bptaddr; |
| 440 | create_thread_event_breakpoint (td_death_bp_addr); |
| 441 | } |
| 442 | |
| 443 | static void |
| 444 | disable_thread_event_reporting (void) |
| 445 | { |
| 446 | td_thr_events_t events; |
| 447 | |
| 448 | /* Set the process wide mask saying we aren't interested in any |
| 449 | events anymore. */ |
| 450 | td_event_emptyset (&events); |
| 451 | td_ta_set_event_p (thread_agent, &events); |
| 452 | |
| 453 | /* Delete thread event breakpoints, if any. */ |
| 454 | remove_thread_event_breakpoints (); |
| 455 | td_create_bp_addr = 0; |
| 456 | td_death_bp_addr = 0; |
| 457 | } |
| 458 | |
| 459 | static void |
| 460 | check_thread_signals (void) |
| 461 | { |
| 462 | #ifdef GET_THREAD_SIGNALS |
| 463 | if (! thread_signals) |
| 464 | { |
| 465 | sigset_t mask; |
| 466 | int i; |
| 467 | |
| 468 | GET_THREAD_SIGNALS (&mask); |
| 469 | sigemptyset (&thread_stop_set); |
| 470 | sigemptyset (&thread_print_set); |
| 471 | |
| 472 | for (i = 0; i < NSIG; i++) |
| 473 | { |
| 474 | if (sigismember (&mask, i)) |
| 475 | { |
| 476 | if (signal_stop_update (target_signal_from_host (i), 0)) |
| 477 | sigaddset (&thread_stop_set, i); |
| 478 | if (signal_print_update (target_signal_from_host (i), 0)) |
| 479 | sigaddset (&thread_print_set, i); |
| 480 | thread_signals = 1; |
| 481 | } |
| 482 | } |
| 483 | } |
| 484 | #endif |
| 485 | } |
| 486 | |
| 487 | static void |
| 488 | disable_thread_signals (void) |
| 489 | { |
| 490 | #ifdef GET_THREAD_SIGNALS |
| 491 | if (thread_signals) |
| 492 | { |
| 493 | int i; |
| 494 | |
| 495 | for (i = 0; i < NSIG; i++) |
| 496 | { |
| 497 | if (sigismember (&thread_stop_set, i)) |
| 498 | signal_stop_update (target_signal_from_host (i), 1); |
| 499 | if (sigismember (&thread_print_set, i)) |
| 500 | signal_print_update (target_signal_from_host (i), 1); |
| 501 | } |
| 502 | |
| 503 | thread_signals = 0; |
| 504 | } |
| 505 | #endif |
| 506 | } |
| 507 | |
| 508 | static void |
| 509 | deactivate_target (void) |
| 510 | { |
| 511 | /* Forget about the child's process ID. We shouldn't need it |
| 512 | anymore. */ |
| 513 | proc_handle.pid = 0; |
| 514 | |
| 515 | if (! keep_thread_db) |
| 516 | { |
| 517 | using_thread_db = 0; |
| 518 | unpush_target (&thread_db_ops); |
| 519 | } |
| 520 | } |
| 521 | |
| 522 | static void |
| 523 | thread_db_new_objfile (struct objfile *objfile) |
| 524 | { |
| 525 | td_err_e err; |
| 526 | |
| 527 | if (objfile == NULL) |
| 528 | { |
| 529 | /* All symbols have been discarded. If the thread_db target is |
| 530 | active, deactivate it now, even if the application was linked |
| 531 | statically against the thread library. */ |
| 532 | keep_thread_db = 0; |
| 533 | if (using_thread_db) |
| 534 | deactivate_target (); |
| 535 | |
| 536 | goto quit; |
| 537 | } |
| 538 | |
| 539 | if (using_thread_db) |
| 540 | /* Nothing to do. The thread library was already detected and the |
| 541 | target vector was already activated. */ |
| 542 | goto quit; |
| 543 | |
| 544 | /* Initialize the structure that identifies the child process. Note |
| 545 | that at this point there is no guarantee that we actually have a |
| 546 | child process. */ |
| 547 | proc_handle.pid = GET_PID (inferior_pid); |
| 548 | |
| 549 | /* Now attempt to open a connection to the thread library. */ |
| 550 | err = td_ta_new_p (&proc_handle, &thread_agent); |
| 551 | switch (err) |
| 552 | { |
| 553 | case TD_NOLIBTHREAD: |
| 554 | /* No thread library was detected. */ |
| 555 | break; |
| 556 | |
| 557 | case TD_OK: |
| 558 | /* The thread library was detected. Activate the thread_db target. */ |
| 559 | push_target (&thread_db_ops); |
| 560 | using_thread_db = 1; |
| 561 | |
| 562 | /* If the thread library was detected in the main symbol file |
| 563 | itself, we assume that the program was statically linked |
| 564 | against the thread library and well have to keep this |
| 565 | module's target vector activated until forever... Well, at |
| 566 | least until all symbols have been discarded anyway (see |
| 567 | above). */ |
| 568 | if (objfile == symfile_objfile) |
| 569 | { |
| 570 | gdb_assert (proc_handle.pid == 0); |
| 571 | keep_thread_db = 1; |
| 572 | } |
| 573 | |
| 574 | /* We can only poke around if there actually is a child process. |
| 575 | If there is no child process alive, postpone the steps below |
| 576 | until one has been created. */ |
| 577 | if (proc_handle.pid != 0) |
| 578 | { |
| 579 | enable_thread_event_reporting (); |
| 580 | thread_db_find_new_threads (); |
| 581 | } |
| 582 | break; |
| 583 | |
| 584 | default: |
| 585 | warning ("Cannot initialize thread debugging library: %s", |
| 586 | thread_db_err_str (err)); |
| 587 | break; |
| 588 | } |
| 589 | |
| 590 | quit: |
| 591 | if (target_new_objfile_chain) |
| 592 | target_new_objfile_chain (objfile); |
| 593 | } |
| 594 | |
| 595 | static void |
| 596 | attach_thread (int pid, const td_thrhandle_t *th_p, |
| 597 | const td_thrinfo_t *ti_p, int verbose) |
| 598 | { |
| 599 | struct thread_info *tp; |
| 600 | td_err_e err; |
| 601 | |
| 602 | check_thread_signals (); |
| 603 | |
| 604 | if (verbose) |
| 605 | printf_unfiltered ("[New %s]\n", target_pid_to_str (pid)); |
| 606 | |
| 607 | /* Add the thread to GDB's thread list. */ |
| 608 | tp = add_thread (pid); |
| 609 | tp->private = xmalloc (sizeof (struct private_thread_info)); |
| 610 | tp->private->lwpid = ti_p->ti_lid; |
| 611 | |
| 612 | /* Under Linux, we have to attach to each and every thread. */ |
| 613 | #ifdef ATTACH_LWP |
| 614 | if (ti_p->ti_lid != GET_PID (pid)) |
| 615 | ATTACH_LWP (BUILD_LWP (ti_p->ti_lid, GET_PID (pid)), 0); |
| 616 | #endif |
| 617 | |
| 618 | /* Enable thread event reporting for this thread. */ |
| 619 | err = td_thr_event_enable_p (th_p, 1); |
| 620 | if (err != TD_OK) |
| 621 | error ("Cannot enable thread event reporting for %s: %s", |
| 622 | target_pid_to_str (pid), thread_db_err_str (err)); |
| 623 | } |
| 624 | |
| 625 | static void |
| 626 | detach_thread (int pid, int verbose) |
| 627 | { |
| 628 | if (verbose) |
| 629 | printf_unfiltered ("[%s exited]\n", target_pid_to_str (pid)); |
| 630 | } |
| 631 | |
| 632 | static void |
| 633 | thread_db_detach (char *args, int from_tty) |
| 634 | { |
| 635 | disable_thread_event_reporting (); |
| 636 | deactivate_target (); |
| 637 | |
| 638 | target_beneath->to_detach (args, from_tty); |
| 639 | } |
| 640 | |
| 641 | static void |
| 642 | thread_db_resume (int pid, int step, enum target_signal signo) |
| 643 | { |
| 644 | struct cleanup *old_chain = save_inferior_pid (); |
| 645 | |
| 646 | if (pid == -1) |
| 647 | inferior_pid = lwp_from_thread (inferior_pid); |
| 648 | else if (is_thread (pid)) |
| 649 | pid = lwp_from_thread (pid); |
| 650 | |
| 651 | target_beneath->to_resume (pid, step, signo); |
| 652 | |
| 653 | do_cleanups (old_chain); |
| 654 | } |
| 655 | |
| 656 | /* Check if PID is currently stopped at the location of a thread event |
| 657 | breakpoint location. If it is, read the event message and act upon |
| 658 | the event. */ |
| 659 | |
| 660 | static void |
| 661 | check_event (int pid) |
| 662 | { |
| 663 | td_event_msg_t msg; |
| 664 | td_thrinfo_t ti; |
| 665 | td_err_e err; |
| 666 | CORE_ADDR stop_pc; |
| 667 | |
| 668 | /* Bail out early if we're not at a thread event breakpoint. */ |
| 669 | stop_pc = read_pc_pid (pid) - DECR_PC_AFTER_BREAK; |
| 670 | if (stop_pc != td_create_bp_addr && stop_pc != td_death_bp_addr) |
| 671 | return; |
| 672 | |
| 673 | err = td_ta_event_getmsg_p (thread_agent, &msg); |
| 674 | if (err != TD_OK) |
| 675 | { |
| 676 | if (err == TD_NOMSG) |
| 677 | return; |
| 678 | |
| 679 | error ("Cannot get thread event message: %s", thread_db_err_str (err)); |
| 680 | } |
| 681 | |
| 682 | err = td_thr_get_info_p (msg.th_p, &ti); |
| 683 | if (err != TD_OK) |
| 684 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 685 | |
| 686 | pid = BUILD_THREAD (ti.ti_tid, GET_PID (pid)); |
| 687 | |
| 688 | switch (msg.event) |
| 689 | { |
| 690 | case TD_CREATE: |
| 691 | #if 0 |
| 692 | /* FIXME: kettenis/2000-08-26: Since we use td_ta_event_getmsg, |
| 693 | there is no guarantee that the breakpoint will match the |
| 694 | event. Should we use td_thr_event_getmsg instead? */ |
| 695 | |
| 696 | if (stop_pc != td_create_bp_addr) |
| 697 | error ("Thread creation event doesn't match breakpoint."); |
| 698 | #endif |
| 699 | |
| 700 | if (in_thread_list (pid)) |
| 701 | error ("Spurious thread creation event."); |
| 702 | |
| 703 | attach_thread (pid, msg.th_p, &ti, 1); |
| 704 | return; |
| 705 | |
| 706 | case TD_DEATH: |
| 707 | #if 0 |
| 708 | /* FIXME: See TD_CREATE. */ |
| 709 | |
| 710 | if (stop_pc != td_death_bp_addr) |
| 711 | error ("Thread death event doesn't match breakpoint."); |
| 712 | #endif |
| 713 | |
| 714 | if (! in_thread_list (pid)) |
| 715 | error ("Spurious thread death event."); |
| 716 | |
| 717 | detach_thread (pid, 1); |
| 718 | return; |
| 719 | |
| 720 | default: |
| 721 | error ("Spurious thread event."); |
| 722 | } |
| 723 | } |
| 724 | |
| 725 | static int |
| 726 | thread_db_wait (int pid, struct target_waitstatus *ourstatus) |
| 727 | { |
| 728 | extern int trap_pid; |
| 729 | |
| 730 | if (pid != -1 && is_thread (pid)) |
| 731 | pid = lwp_from_thread (pid); |
| 732 | |
| 733 | pid = target_beneath->to_wait (pid, ourstatus); |
| 734 | |
| 735 | if (proc_handle.pid == 0) |
| 736 | /* The current child process isn't the actual multi-threaded |
| 737 | program yet, so don't try to do any special thread-specific |
| 738 | post-processing and bail out early. */ |
| 739 | return pid; |
| 740 | |
| 741 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
| 742 | return -1; |
| 743 | |
| 744 | if (ourstatus->kind == TARGET_WAITKIND_STOPPED |
| 745 | && ourstatus->value.sig == TARGET_SIGNAL_TRAP) |
| 746 | /* Check for a thread event. */ |
| 747 | check_event (pid); |
| 748 | |
| 749 | if (trap_pid) |
| 750 | trap_pid = thread_from_lwp (trap_pid); |
| 751 | |
| 752 | return thread_from_lwp (pid); |
| 753 | } |
| 754 | |
| 755 | static int |
| 756 | thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write, |
| 757 | struct mem_attrib *attrib, |
| 758 | struct target_ops *target) |
| 759 | { |
| 760 | struct cleanup *old_chain = save_inferior_pid (); |
| 761 | int xfer; |
| 762 | |
| 763 | if (is_thread (inferior_pid)) |
| 764 | { |
| 765 | /* FIXME: This seems to be necessary to make sure breakpoints |
| 766 | are removed. */ |
| 767 | if (! target_thread_alive (inferior_pid)) |
| 768 | inferior_pid = GET_PID (inferior_pid); |
| 769 | else |
| 770 | inferior_pid = lwp_from_thread (inferior_pid); |
| 771 | } |
| 772 | |
| 773 | xfer = target_beneath->to_xfer_memory (memaddr, myaddr, len, write, attrib, target); |
| 774 | |
| 775 | do_cleanups (old_chain); |
| 776 | return xfer; |
| 777 | } |
| 778 | |
| 779 | static void |
| 780 | thread_db_fetch_registers (int regno) |
| 781 | { |
| 782 | td_thrhandle_t th; |
| 783 | prgregset_t gregset; |
| 784 | gdb_prfpregset_t fpregset; |
| 785 | td_err_e err; |
| 786 | |
| 787 | if (! is_thread (inferior_pid)) |
| 788 | { |
| 789 | /* Pass the request to the target beneath us. */ |
| 790 | target_beneath->to_fetch_registers (regno); |
| 791 | return; |
| 792 | } |
| 793 | |
| 794 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (inferior_pid), &th); |
| 795 | if (err != TD_OK) |
| 796 | error ("Cannot find thread %ld: %s", |
| 797 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 798 | |
| 799 | err = td_thr_getgregs_p (&th, gregset); |
| 800 | if (err != TD_OK) |
| 801 | error ("Cannot fetch general-purpose registers for thread %ld: %s", |
| 802 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 803 | |
| 804 | err = td_thr_getfpregs_p (&th, &fpregset); |
| 805 | if (err != TD_OK) |
| 806 | error ("Cannot get floating-point registers for thread %ld: %s", |
| 807 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 808 | |
| 809 | /* Note that we must call supply_gregset after calling the thread_db |
| 810 | routines because the thread_db routines call ps_lgetgregs and |
| 811 | friends which clobber GDB's register cache. */ |
| 812 | supply_gregset ((gdb_gregset_t *) gregset); |
| 813 | supply_fpregset (&fpregset); |
| 814 | } |
| 815 | |
| 816 | static void |
| 817 | thread_db_store_registers (int regno) |
| 818 | { |
| 819 | td_thrhandle_t th; |
| 820 | prgregset_t gregset; |
| 821 | gdb_prfpregset_t fpregset; |
| 822 | td_err_e err; |
| 823 | |
| 824 | if (! is_thread (inferior_pid)) |
| 825 | { |
| 826 | /* Pass the request to the target beneath us. */ |
| 827 | target_beneath->to_store_registers (regno); |
| 828 | return; |
| 829 | } |
| 830 | |
| 831 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (inferior_pid), &th); |
| 832 | if (err != TD_OK) |
| 833 | error ("Cannot find thread %ld: %s", |
| 834 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 835 | |
| 836 | if (regno != -1) |
| 837 | { |
| 838 | char raw[MAX_REGISTER_RAW_SIZE]; |
| 839 | |
| 840 | read_register_gen (regno, raw); |
| 841 | thread_db_fetch_registers (-1); |
| 842 | supply_register (regno, raw); |
| 843 | } |
| 844 | |
| 845 | fill_gregset ((gdb_gregset_t *) gregset, -1); |
| 846 | fill_fpregset (&fpregset, -1); |
| 847 | |
| 848 | err = td_thr_setgregs_p (&th, gregset); |
| 849 | if (err != TD_OK) |
| 850 | error ("Cannot store general-purpose registers for thread %ld: %s", |
| 851 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 852 | err = td_thr_setfpregs_p (&th, &fpregset); |
| 853 | if (err != TD_OK) |
| 854 | error ("Cannot store floating-point registers for thread %ld: %s", |
| 855 | (long) GET_THREAD (inferior_pid), thread_db_err_str (err)); |
| 856 | } |
| 857 | |
| 858 | static void |
| 859 | thread_db_kill (void) |
| 860 | { |
| 861 | target_beneath->to_kill (); |
| 862 | } |
| 863 | |
| 864 | static void |
| 865 | thread_db_create_inferior (char *exec_file, char *allargs, char **env) |
| 866 | { |
| 867 | target_beneath->to_create_inferior (exec_file, allargs, env); |
| 868 | } |
| 869 | |
| 870 | static void |
| 871 | thread_db_post_startup_inferior (int pid) |
| 872 | { |
| 873 | if (proc_handle.pid == 0) |
| 874 | { |
| 875 | /* The child process is now the actual multi-threaded |
| 876 | program. Snatch its process ID... */ |
| 877 | proc_handle.pid = GET_PID (pid); |
| 878 | |
| 879 | /* ...and perform the remaining initialization steps. */ |
| 880 | enable_thread_event_reporting (); |
| 881 | thread_db_find_new_threads(); |
| 882 | } |
| 883 | } |
| 884 | |
| 885 | static void |
| 886 | thread_db_mourn_inferior (void) |
| 887 | { |
| 888 | remove_thread_event_breakpoints (); |
| 889 | deactivate_target (); |
| 890 | |
| 891 | target_beneath->to_mourn_inferior (); |
| 892 | } |
| 893 | |
| 894 | static int |
| 895 | thread_db_thread_alive (int pid) |
| 896 | { |
| 897 | if (is_thread (pid)) |
| 898 | { |
| 899 | td_thrhandle_t th; |
| 900 | td_err_e err; |
| 901 | |
| 902 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th); |
| 903 | if (err != TD_OK) |
| 904 | return 0; |
| 905 | |
| 906 | err = td_thr_validate_p (&th); |
| 907 | if (err != TD_OK) |
| 908 | return 0; |
| 909 | |
| 910 | return 1; |
| 911 | } |
| 912 | |
| 913 | if (target_beneath->to_thread_alive) |
| 914 | return target_beneath->to_thread_alive (pid); |
| 915 | |
| 916 | return 0; |
| 917 | } |
| 918 | |
| 919 | static int |
| 920 | find_new_threads_callback (const td_thrhandle_t *th_p, void *data) |
| 921 | { |
| 922 | td_thrinfo_t ti; |
| 923 | td_err_e err; |
| 924 | int pid; |
| 925 | |
| 926 | err = td_thr_get_info_p (th_p, &ti); |
| 927 | if (err != TD_OK) |
| 928 | error ("Cannot get thread info: %s", thread_db_err_str (err)); |
| 929 | |
| 930 | pid = BUILD_THREAD (ti.ti_tid, GET_PID (inferior_pid)); |
| 931 | |
| 932 | if (! in_thread_list (pid)) |
| 933 | attach_thread (pid, th_p, &ti, 1); |
| 934 | |
| 935 | return 0; |
| 936 | } |
| 937 | |
| 938 | static void |
| 939 | thread_db_find_new_threads (void) |
| 940 | { |
| 941 | td_err_e err; |
| 942 | |
| 943 | /* Iterate over all user-space threads to discover new threads. */ |
| 944 | err = td_ta_thr_iter_p (thread_agent, find_new_threads_callback, NULL, |
| 945 | TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY, |
| 946 | TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS); |
| 947 | if (err != TD_OK) |
| 948 | error ("Cannot find new threads: %s", thread_db_err_str (err)); |
| 949 | } |
| 950 | |
| 951 | static char * |
| 952 | thread_db_pid_to_str (int pid) |
| 953 | { |
| 954 | if (is_thread (pid)) |
| 955 | { |
| 956 | static char buf[64]; |
| 957 | td_thrhandle_t th; |
| 958 | td_thrinfo_t ti; |
| 959 | td_err_e err; |
| 960 | |
| 961 | err = td_ta_map_id2thr_p (thread_agent, GET_THREAD (pid), &th); |
| 962 | if (err != TD_OK) |
| 963 | error ("Cannot find thread %ld: %s", |
| 964 | (long) GET_THREAD (pid), thread_db_err_str (err)); |
| 965 | |
| 966 | err = td_thr_get_info_p (&th, &ti); |
| 967 | if (err != TD_OK) |
| 968 | error ("Cannot get thread info for thread %ld: %s", |
| 969 | (long) GET_THREAD (pid), thread_db_err_str (err)); |
| 970 | |
| 971 | if (ti.ti_state == TD_THR_ACTIVE && ti.ti_lid != 0) |
| 972 | { |
| 973 | snprintf (buf, sizeof (buf), "Thread %ld (LWP %d)", |
| 974 | (long) ti.ti_tid, ti.ti_lid); |
| 975 | } |
| 976 | else |
| 977 | { |
| 978 | snprintf (buf, sizeof (buf), "Thread %ld (%s)", |
| 979 | (long) ti.ti_tid, thread_db_state_str (ti.ti_state)); |
| 980 | } |
| 981 | |
| 982 | return buf; |
| 983 | } |
| 984 | |
| 985 | if (target_beneath->to_pid_to_str (pid)) |
| 986 | return target_beneath->to_pid_to_str (pid); |
| 987 | |
| 988 | return normal_pid_to_str (pid); |
| 989 | } |
| 990 | |
| 991 | static void |
| 992 | init_thread_db_ops (void) |
| 993 | { |
| 994 | thread_db_ops.to_shortname = "multi-thread"; |
| 995 | thread_db_ops.to_longname = "multi-threaded child process."; |
| 996 | thread_db_ops.to_doc = "Threads and pthreads support."; |
| 997 | thread_db_ops.to_detach = thread_db_detach; |
| 998 | thread_db_ops.to_resume = thread_db_resume; |
| 999 | thread_db_ops.to_wait = thread_db_wait; |
| 1000 | thread_db_ops.to_fetch_registers = thread_db_fetch_registers; |
| 1001 | thread_db_ops.to_store_registers = thread_db_store_registers; |
| 1002 | thread_db_ops.to_xfer_memory = thread_db_xfer_memory; |
| 1003 | thread_db_ops.to_kill = thread_db_kill; |
| 1004 | thread_db_ops.to_create_inferior = thread_db_create_inferior; |
| 1005 | thread_db_ops.to_post_startup_inferior = thread_db_post_startup_inferior; |
| 1006 | thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior; |
| 1007 | thread_db_ops.to_thread_alive = thread_db_thread_alive; |
| 1008 | thread_db_ops.to_find_new_threads = thread_db_find_new_threads; |
| 1009 | thread_db_ops.to_pid_to_str = thread_db_pid_to_str; |
| 1010 | thread_db_ops.to_stratum = thread_stratum; |
| 1011 | thread_db_ops.to_has_thread_control = tc_schedlock; |
| 1012 | thread_db_ops.to_magic = OPS_MAGIC; |
| 1013 | } |
| 1014 | |
| 1015 | void |
| 1016 | _initialize_thread_db (void) |
| 1017 | { |
| 1018 | /* Only initialize the module if we can load libthread_db. */ |
| 1019 | if (thread_db_load ()) |
| 1020 | { |
| 1021 | init_thread_db_ops (); |
| 1022 | add_target (&thread_db_ops); |
| 1023 | |
| 1024 | /* Add ourselves to objfile event chain. */ |
| 1025 | target_new_objfile_chain = target_new_objfile_hook; |
| 1026 | target_new_objfile_hook = thread_db_new_objfile; |
| 1027 | } |
| 1028 | } |