| 1 | /* Multi-threaded debugging support for the thread_db interface, |
| 2 | used on operating systems such as Solaris and Linux. |
| 3 | Copyright 1999 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 | /* This module implements a thread_stratum target that sits on top of |
| 23 | a normal process_stratum target (such as procfs or ptrace). The |
| 24 | process_stratum target must install this thread_stratum target when |
| 25 | it detects the presence of the thread_db shared library. |
| 26 | |
| 27 | This module will then use the thread_db API to add thread-awareness |
| 28 | to the functionality provided by the process_stratum target (or in |
| 29 | some cases, to add user-level thread awareness on top of the |
| 30 | kernel-level thread awareness that is already provided by the |
| 31 | process_stratum target). |
| 32 | |
| 33 | Solaris threads (for instance) are a multi-level thread implementation; |
| 34 | the kernel provides a Light Weight Process (LWP) which the procfs |
| 35 | process_stratum module is aware of. This module must then mediate |
| 36 | the relationship between kernel LWP threads and user (eg. posix) |
| 37 | threads. |
| 38 | |
| 39 | Linux threads are likely to be different -- but the thread_db |
| 40 | library API should make the difference largely transparent to GDB. |
| 41 | |
| 42 | */ |
| 43 | |
| 44 | /* The thread_db API provides a number of functions that give the caller |
| 45 | access to the inner workings of the child process's thread library. |
| 46 | We will be using the following (others may be added): |
| 47 | |
| 48 | td_thr_validate Confirm valid "live" thread |
| 49 | td_thr_get_info Get info about a thread |
| 50 | td_thr_getgregs Get thread's general registers |
| 51 | td_thr_getfpregs Get thread's floating point registers |
| 52 | td_thr_setgregs Set thread's general registers |
| 53 | td_thr_setfpregs Set thread's floating point registers |
| 54 | td_ta_map_id2thr Get thread handle from thread id |
| 55 | td_ta_map_lwp2thr Get thread handle from LWP id |
| 56 | td_ta_thr_iter Iterate over all threads (with callback) |
| 57 | |
| 58 | In return, the debugger has to provide certain services to the |
| 59 | thread_db library. Some of these aren't actually required to do |
| 60 | anything in practice. For instance, the thread_db expects to be |
| 61 | able to stop the child process and start it again: but in our |
| 62 | context, the child process will always be stopped already when we |
| 63 | invoke the thread_db library, so the functions that we provide for |
| 64 | the library to stop and start the child process are no-ops. |
| 65 | |
| 66 | Here is the list of functions which we export to the thread_db |
| 67 | library, divided into no-op functions vs. functions that actually |
| 68 | have to do something: |
| 69 | |
| 70 | No-op functions: |
| 71 | |
| 72 | ps_pstop Stop the child process |
| 73 | ps_pcontinue Continue the child process |
| 74 | ps_lstop Stop a specific LWP (kernel thread) |
| 75 | ps_lcontinue Continue an LWP |
| 76 | ps_lgetxregsize Get size of LWP's xregs (sparc) |
| 77 | ps_lgetxregs Get LWP's xregs (sparc) |
| 78 | ps_lsetxregs Set LWP's xregs (sparc) |
| 79 | |
| 80 | Functions that have to do useful work: |
| 81 | |
| 82 | ps_pglobal_lookup Get the address of a global symbol |
| 83 | ps_pdread Read memory, data segment |
| 84 | ps_ptread Read memory, text segment |
| 85 | ps_pdwrite Write memory, data segment |
| 86 | ps_ptwrite Write memory, text segment |
| 87 | ps_lgetregs Get LWP's general registers |
| 88 | ps_lgetfpregs Get LWP's floating point registers |
| 89 | ps_lsetregs Set LWP's general registers |
| 90 | ps_lsetfpregs Set LWP's floating point registers |
| 91 | ps_lgetLDT Get LWP's Local Descriptor Table (x86) |
| 92 | |
| 93 | Thus, if we ask the thread_db library to give us the general registers |
| 94 | for user thread X, thread_db may figure out that user thread X is |
| 95 | actually mapped onto kernel thread Y. Thread_db does not know how |
| 96 | to obtain the registers for kernel thread Y, but GDB does, so thread_db |
| 97 | turns the request right back to us via the ps_lgetregs callback. */ |
| 98 | |
| 99 | #include "defs.h" |
| 100 | #include "gdbthread.h" |
| 101 | #include "target.h" |
| 102 | #include "inferior.h" |
| 103 | #include "gdbcmd.h" |
| 104 | |
| 105 | #include "gdb_wait.h" |
| 106 | |
| 107 | #include <time.h> |
| 108 | |
| 109 | #if defined(USE_PROC_FS) || defined(HAVE_GREGSET_T) |
| 110 | #include <sys/procfs.h> |
| 111 | #endif |
| 112 | |
| 113 | #include "gdb_proc_service.h" |
| 114 | |
| 115 | #if defined HAVE_STDINT_H /* Pre-5.2 systems don't have this header */ |
| 116 | #if defined (HAVE_THREAD_DB_H) |
| 117 | #include <thread_db.h> /* defines outgoing API (td_thr_* calls) */ |
| 118 | #else |
| 119 | #include "gdb_thread_db.h" |
| 120 | #endif |
| 121 | |
| 122 | #include <dlfcn.h> /* dynamic library interface */ |
| 123 | |
| 124 | /* Prototypes for supply_gregset etc. */ |
| 125 | #include "gregset.h" |
| 126 | |
| 127 | #ifndef TIDGET |
| 128 | #define TIDGET(PID) (((PID) & 0x7fffffff) >> 16) |
| 129 | #define PIDGET(PID) (((PID) & 0xffff)) |
| 130 | #define MERGEPID(PID, TID) (((PID) & 0xffff) | ((TID) << 16)) |
| 131 | #endif |
| 132 | |
| 133 | /* Macros for superimposing PID and TID into inferior_pid. */ |
| 134 | #define THREAD_FLAG 0x80000000 |
| 135 | #define is_thread(ARG) (((ARG) & THREAD_FLAG) != 0) |
| 136 | #define is_lwp(ARG) (((ARG) & THREAD_FLAG) == 0) |
| 137 | #define GET_LWP(PID) TIDGET (PID) |
| 138 | #define GET_THREAD(PID) TIDGET (PID) |
| 139 | #define BUILD_LWP(TID, PID) MERGEPID (PID, TID) |
| 140 | #define BUILD_THREAD(TID, PID) (MERGEPID (PID, TID) | THREAD_FLAG) |
| 141 | |
| 142 | /* |
| 143 | * target_beneath is a pointer to the target_ops underlying this one. |
| 144 | */ |
| 145 | |
| 146 | static struct target_ops *target_beneath; |
| 147 | |
| 148 | |
| 149 | /* |
| 150 | * target vector defined in this module: |
| 151 | */ |
| 152 | |
| 153 | static struct target_ops thread_db_ops; |
| 154 | |
| 155 | /* |
| 156 | * Typedefs required to resolve differences between the thread_db |
| 157 | * and proc_service API defined on different versions of Solaris: |
| 158 | */ |
| 159 | |
| 160 | #if defined(PROC_SERVICE_IS_OLD) |
| 161 | typedef const struct ps_prochandle *gdb_ps_prochandle_t; |
| 162 | typedef char *gdb_ps_read_buf_t; |
| 163 | typedef char *gdb_ps_write_buf_t; |
| 164 | typedef int gdb_ps_size_t; |
| 165 | #else |
| 166 | typedef struct ps_prochandle *gdb_ps_prochandle_t; |
| 167 | typedef void *gdb_ps_read_buf_t; |
| 168 | typedef const void *gdb_ps_write_buf_t; |
| 169 | typedef size_t gdb_ps_size_t; |
| 170 | #endif |
| 171 | |
| 172 | /* |
| 173 | * proc_service callback functions, called by thread_db. |
| 174 | */ |
| 175 | |
| 176 | ps_err_e |
| 177 | ps_pstop (gdb_ps_prochandle_t ph) /* Process stop */ |
| 178 | { |
| 179 | return PS_OK; |
| 180 | } |
| 181 | |
| 182 | ps_err_e |
| 183 | ps_pcontinue (gdb_ps_prochandle_t ph) /* Process continue */ |
| 184 | { |
| 185 | return PS_OK; |
| 186 | } |
| 187 | |
| 188 | ps_err_e |
| 189 | ps_lstop (gdb_ps_prochandle_t ph, /* LWP stop */ |
| 190 | lwpid_t lwpid) |
| 191 | { |
| 192 | return PS_OK; |
| 193 | } |
| 194 | |
| 195 | ps_err_e |
| 196 | ps_lcontinue (gdb_ps_prochandle_t ph, /* LWP continue */ |
| 197 | lwpid_t lwpid) |
| 198 | { |
| 199 | return PS_OK; |
| 200 | } |
| 201 | |
| 202 | ps_err_e |
| 203 | ps_lgetxregsize (gdb_ps_prochandle_t ph, /* Get XREG size */ |
| 204 | lwpid_t lwpid, |
| 205 | int *xregsize) |
| 206 | { |
| 207 | return PS_OK; |
| 208 | } |
| 209 | |
| 210 | ps_err_e |
| 211 | ps_lgetxregs (gdb_ps_prochandle_t ph, /* Get XREGS */ |
| 212 | lwpid_t lwpid, |
| 213 | caddr_t xregset) |
| 214 | { |
| 215 | return PS_OK; |
| 216 | } |
| 217 | |
| 218 | ps_err_e |
| 219 | ps_lsetxregs (gdb_ps_prochandle_t ph, /* Set XREGS */ |
| 220 | lwpid_t lwpid, |
| 221 | caddr_t xregset) |
| 222 | { |
| 223 | return PS_OK; |
| 224 | } |
| 225 | |
| 226 | void |
| 227 | ps_plog (const char *fmt, ...) |
| 228 | { |
| 229 | va_list args; |
| 230 | |
| 231 | va_start (args, fmt); |
| 232 | vfprintf_filtered (gdb_stderr, fmt, args); |
| 233 | } |
| 234 | |
| 235 | /* Look up a symbol in GDB's global symbol table. |
| 236 | Return the symbol's address. |
| 237 | FIXME: it would be more correct to look up the symbol in the context |
| 238 | of the LD_OBJECT_NAME provided. However we're probably fairly safe |
| 239 | as long as there aren't name conflicts with other libraries. */ |
| 240 | |
| 241 | ps_err_e |
| 242 | ps_pglobal_lookup (gdb_ps_prochandle_t ph, |
| 243 | const char *ld_object_name, /* the library name */ |
| 244 | const char *ld_symbol_name, /* the symbol name */ |
| 245 | paddr_t *ld_symbol_addr) /* return the symbol addr */ |
| 246 | { |
| 247 | struct minimal_symbol *ms; |
| 248 | |
| 249 | ms = lookup_minimal_symbol (ld_symbol_name, NULL, NULL); |
| 250 | |
| 251 | if (!ms) |
| 252 | return PS_NOSYM; |
| 253 | |
| 254 | *ld_symbol_addr = SYMBOL_VALUE_ADDRESS (ms); |
| 255 | |
| 256 | return PS_OK; |
| 257 | } |
| 258 | |
| 259 | /* Worker function for all memory reads and writes: */ |
| 260 | static ps_err_e rw_common (const struct ps_prochandle *ph, |
| 261 | paddr_t addr, |
| 262 | char *buf, |
| 263 | int size, |
| 264 | int write_p); |
| 265 | |
| 266 | /* target_xfer_memory direction consts */ |
| 267 | enum {PS_READ = 0, PS_WRITE = 1}; |
| 268 | |
| 269 | ps_err_e |
| 270 | ps_pdread (gdb_ps_prochandle_t ph, /* read from data segment */ |
| 271 | paddr_t addr, |
| 272 | gdb_ps_read_buf_t buf, |
| 273 | gdb_ps_size_t size) |
| 274 | { |
| 275 | return rw_common (ph, addr, buf, size, PS_READ); |
| 276 | } |
| 277 | |
| 278 | ps_err_e |
| 279 | ps_pdwrite (gdb_ps_prochandle_t ph, /* write to data segment */ |
| 280 | paddr_t addr, |
| 281 | gdb_ps_write_buf_t buf, |
| 282 | gdb_ps_size_t size) |
| 283 | { |
| 284 | return rw_common (ph, addr, (char *) buf, size, PS_WRITE); |
| 285 | } |
| 286 | |
| 287 | ps_err_e |
| 288 | ps_ptread (gdb_ps_prochandle_t ph, /* read from text segment */ |
| 289 | paddr_t addr, |
| 290 | gdb_ps_read_buf_t buf, |
| 291 | gdb_ps_size_t size) |
| 292 | { |
| 293 | return rw_common (ph, addr, buf, size, PS_READ); |
| 294 | } |
| 295 | |
| 296 | ps_err_e |
| 297 | ps_ptwrite (gdb_ps_prochandle_t ph, /* write to text segment */ |
| 298 | paddr_t addr, |
| 299 | gdb_ps_write_buf_t buf, |
| 300 | gdb_ps_size_t size) |
| 301 | { |
| 302 | return rw_common (ph, addr, (char *) buf, size, PS_WRITE); |
| 303 | } |
| 304 | |
| 305 | static struct cleanup *save_inferior_pid (void); |
| 306 | static void restore_inferior_pid (void *saved_pid); |
| 307 | static char *thr_err_string (td_err_e); |
| 308 | static char *thr_state_string (td_thr_state_e); |
| 309 | |
| 310 | struct ps_prochandle main_prochandle; |
| 311 | td_thragent_t * main_threadagent; |
| 312 | |
| 313 | /* |
| 314 | * Common proc_service routine for reading and writing memory. |
| 315 | */ |
| 316 | |
| 317 | /* FIXME: once we've munged the inferior_pid, why can't we |
| 318 | simply call target_read/write_memory and return? */ |
| 319 | |
| 320 | |
| 321 | static ps_err_e |
| 322 | rw_common (const struct ps_prochandle *ph, |
| 323 | paddr_t addr, |
| 324 | char *buf, |
| 325 | int size, |
| 326 | int write_p) |
| 327 | { |
| 328 | struct cleanup *old_chain = save_inferior_pid (); |
| 329 | int to_do = size; |
| 330 | int done = 0; |
| 331 | |
| 332 | inferior_pid = main_prochandle.pid; |
| 333 | |
| 334 | while (to_do > 0) |
| 335 | { |
| 336 | done = current_target.to_xfer_memory (addr, buf, size, write_p, |
| 337 | ¤t_target); |
| 338 | if (done <= 0) |
| 339 | { |
| 340 | if (write_p == PS_READ) |
| 341 | print_sys_errmsg ("rw_common (): read", errno); |
| 342 | else |
| 343 | print_sys_errmsg ("rw_common (): write", errno); |
| 344 | |
| 345 | return PS_ERR; |
| 346 | } |
| 347 | to_do -= done; |
| 348 | buf += done; |
| 349 | } |
| 350 | do_cleanups (old_chain); |
| 351 | return PS_OK; |
| 352 | } |
| 353 | |
| 354 | /* Cleanup functions used by the register callbacks |
| 355 | (which have to manipulate the global inferior_pid). */ |
| 356 | |
| 357 | ps_err_e |
| 358 | ps_lgetregs (gdb_ps_prochandle_t ph, /* Get LWP general regs */ |
| 359 | lwpid_t lwpid, |
| 360 | prgregset_t gregset) |
| 361 | { |
| 362 | struct cleanup *old_chain = save_inferior_pid (); |
| 363 | |
| 364 | inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| 365 | current_target.to_fetch_registers (-1); |
| 366 | |
| 367 | fill_gregset (gregset, -1); |
| 368 | do_cleanups (old_chain); |
| 369 | |
| 370 | return PS_OK; |
| 371 | } |
| 372 | |
| 373 | ps_err_e |
| 374 | ps_lsetregs (gdb_ps_prochandle_t ph, /* Set LWP general regs */ |
| 375 | lwpid_t lwpid, |
| 376 | const prgregset_t gregset) |
| 377 | { |
| 378 | struct cleanup *old_chain = save_inferior_pid (); |
| 379 | |
| 380 | inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| 381 | supply_gregset (gregset); |
| 382 | current_target.to_store_registers (-1); |
| 383 | do_cleanups (old_chain); |
| 384 | return PS_OK; |
| 385 | } |
| 386 | |
| 387 | ps_err_e |
| 388 | ps_lgetfpregs (gdb_ps_prochandle_t ph, /* Get LWP float regs */ |
| 389 | lwpid_t lwpid, |
| 390 | gdb_prfpregset_t *fpregset) |
| 391 | { |
| 392 | struct cleanup *old_chain = save_inferior_pid (); |
| 393 | |
| 394 | inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| 395 | current_target.to_fetch_registers (-1); |
| 396 | fill_fpregset (fpregset, -1); |
| 397 | do_cleanups (old_chain); |
| 398 | return PS_OK; |
| 399 | } |
| 400 | |
| 401 | ps_err_e |
| 402 | ps_lsetfpregs (gdb_ps_prochandle_t ph, /* Set LWP float regs */ |
| 403 | lwpid_t lwpid, |
| 404 | const gdb_prfpregset_t *fpregset) |
| 405 | { |
| 406 | struct cleanup *old_chain = save_inferior_pid (); |
| 407 | |
| 408 | inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| 409 | supply_fpregset (fpregset); |
| 410 | current_target.to_store_registers (-1); |
| 411 | do_cleanups (old_chain); |
| 412 | return PS_OK; |
| 413 | } |
| 414 | |
| 415 | /* |
| 416 | * ps_getpid |
| 417 | * |
| 418 | * return the main pid for the child process |
| 419 | * (special for Linux -- not used on Solaris) |
| 420 | */ |
| 421 | |
| 422 | pid_t |
| 423 | ps_getpid (gdb_ps_prochandle_t ph) |
| 424 | { |
| 425 | return ph->pid; |
| 426 | } |
| 427 | |
| 428 | #ifdef TM_I386SOL2_H |
| 429 | |
| 430 | /* Reads the local descriptor table of a LWP. */ |
| 431 | |
| 432 | ps_err_e |
| 433 | ps_lgetLDT (gdb_ps_prochandle_t ph, lwpid_t lwpid, |
| 434 | struct ssd *pldt) |
| 435 | { |
| 436 | /* NOTE: only used on Solaris, therefore OK to refer to procfs.c */ |
| 437 | extern struct ssd *procfs_find_LDT_entry (int); |
| 438 | struct ssd *ret; |
| 439 | |
| 440 | ret = procfs_find_LDT_entry (BUILD_LWP (lwpid, |
| 441 | PIDGET (main_prochandle.pid))); |
| 442 | if (ret) |
| 443 | { |
| 444 | memcpy (pldt, ret, sizeof (struct ssd)); |
| 445 | return PS_OK; |
| 446 | } |
| 447 | else /* LDT not found. */ |
| 448 | return PS_ERR; |
| 449 | } |
| 450 | #endif /* TM_I386SOL2_H */ |
| 451 | |
| 452 | /* |
| 453 | * Pointers to thread_db functions: |
| 454 | * |
| 455 | * These are a dynamic library mechanism. |
| 456 | * The dlfcn.h interface will be used to initialize these |
| 457 | * so that they point to the appropriate functions in the |
| 458 | * thread_db dynamic library. This is done dynamically |
| 459 | * so that GDB can still run on systems that lack thread_db. |
| 460 | */ |
| 461 | |
| 462 | static td_err_e (*p_td_init) (void); |
| 463 | |
| 464 | static td_err_e (*p_td_ta_new) (const struct ps_prochandle *ph_p, |
| 465 | td_thragent_t **ta_pp); |
| 466 | |
| 467 | static td_err_e (*p_td_ta_delete) (td_thragent_t *ta_p); |
| 468 | |
| 469 | static td_err_e (*p_td_ta_get_nthreads) (const td_thragent_t *ta_p, |
| 470 | int *nthread_p); |
| 471 | |
| 472 | |
| 473 | static td_err_e (*p_td_ta_thr_iter) (const td_thragent_t *ta_p, |
| 474 | td_thr_iter_f *cb, |
| 475 | void *cbdata_p, |
| 476 | td_thr_state_e state, |
| 477 | int ti_pri, |
| 478 | sigset_t *ti_sigmask_p, |
| 479 | unsigned ti_user_flags); |
| 480 | |
| 481 | static td_err_e (*p_td_ta_event_addr) (const td_thragent_t *ta_p, |
| 482 | u_long event, |
| 483 | td_notify_t *notify_p); |
| 484 | |
| 485 | static td_err_e (*p_td_ta_event_getmsg) (const td_thragent_t *ta_p, |
| 486 | td_event_msg_t *msg); |
| 487 | |
| 488 | static td_err_e (*p_td_ta_set_event) (const td_thragent_t *ta_p, |
| 489 | td_thr_events_t *events); |
| 490 | |
| 491 | static td_err_e (*p_td_thr_validate) (const td_thrhandle_t *th_p); |
| 492 | |
| 493 | static td_err_e (*p_td_thr_event_enable) (const td_thrhandle_t *th_p, |
| 494 | int on_off); |
| 495 | |
| 496 | static td_err_e (*p_td_thr_get_info) (const td_thrhandle_t *th_p, |
| 497 | td_thrinfo_t *ti_p); |
| 498 | |
| 499 | static td_err_e (*p_td_thr_getgregs) (const td_thrhandle_t *th_p, |
| 500 | prgregset_t regset); |
| 501 | |
| 502 | static td_err_e (*p_td_thr_setgregs) (const td_thrhandle_t *th_p, |
| 503 | const prgregset_t regset); |
| 504 | |
| 505 | static td_err_e (*p_td_thr_getfpregs) (const td_thrhandle_t *th_p, |
| 506 | gdb_prfpregset_t *fpregset); |
| 507 | |
| 508 | static td_err_e (*p_td_thr_setfpregs) (const td_thrhandle_t *th_p, |
| 509 | const gdb_prfpregset_t *fpregset); |
| 510 | |
| 511 | static td_err_e (*p_td_ta_map_id2thr) (const td_thragent_t *ta_p, |
| 512 | thread_t tid, |
| 513 | td_thrhandle_t *th_p); |
| 514 | |
| 515 | static td_err_e (*p_td_ta_map_lwp2thr) (const td_thragent_t *ta_p, |
| 516 | lwpid_t lwpid, |
| 517 | td_thrhandle_t *th_p); |
| 518 | |
| 519 | /* |
| 520 | * API and target vector initialization function: thread_db_initialize. |
| 521 | * |
| 522 | * NOTE: this function is deliberately NOT named with the GDB convention |
| 523 | * of module initializer function names that begin with "_initialize". |
| 524 | * This module is NOT intended to be auto-initialized at GDB startup. |
| 525 | * Rather, it will only be initialized when a multi-threaded child |
| 526 | * process is detected. |
| 527 | * |
| 528 | */ |
| 529 | |
| 530 | /* |
| 531 | * Initializer for thread_db library interface. |
| 532 | * This function does the dynamic library stuff (dlopen, dlsym), |
| 533 | * and then calls the thread_db library's one-time initializer |
| 534 | * function (td_init). If everything succeeds, this function |
| 535 | * returns true; otherwise it returns false, and this module |
| 536 | * cannot be used. |
| 537 | */ |
| 538 | |
| 539 | static int |
| 540 | init_thread_db_library (void) |
| 541 | { |
| 542 | void *dlhandle; |
| 543 | td_err_e ret; |
| 544 | |
| 545 | /* Open a handle to the "thread_db" dynamic library. */ |
| 546 | if ((dlhandle = dlopen ("libthread_db.so.1", RTLD_NOW)) == NULL) |
| 547 | return 0; /* fail */ |
| 548 | |
| 549 | /* Initialize pointers to the dynamic library functions we will use. |
| 550 | * Note that we are not calling the functions here -- we are only |
| 551 | * establishing pointers to them. |
| 552 | */ |
| 553 | |
| 554 | /* td_init: initialize thread_db library. */ |
| 555 | if ((p_td_init = dlsym (dlhandle, "td_init")) == NULL) |
| 556 | return 0; /* fail */ |
| 557 | /* td_ta_new: register a target process with thread_db. */ |
| 558 | if ((p_td_ta_new = dlsym (dlhandle, "td_ta_new")) == NULL) |
| 559 | return 0; /* fail */ |
| 560 | /* td_ta_delete: un-register a target process with thread_db. */ |
| 561 | if ((p_td_ta_delete = dlsym (dlhandle, "td_ta_delete")) == NULL) |
| 562 | return 0; /* fail */ |
| 563 | |
| 564 | /* td_ta_map_id2thr: get thread handle from thread id. */ |
| 565 | if ((p_td_ta_map_id2thr = dlsym (dlhandle, "td_ta_map_id2thr")) == NULL) |
| 566 | return 0; /* fail */ |
| 567 | /* td_ta_map_lwp2thr: get thread handle from lwp id. */ |
| 568 | if ((p_td_ta_map_lwp2thr = dlsym (dlhandle, "td_ta_map_lwp2thr")) == NULL) |
| 569 | return 0; /* fail */ |
| 570 | /* td_ta_get_nthreads: get number of threads in target process. */ |
| 571 | if ((p_td_ta_get_nthreads = dlsym (dlhandle, "td_ta_get_nthreads")) == NULL) |
| 572 | return 0; /* fail */ |
| 573 | /* td_ta_thr_iter: iterate over all thread handles. */ |
| 574 | if ((p_td_ta_thr_iter = dlsym (dlhandle, "td_ta_thr_iter")) == NULL) |
| 575 | return 0; /* fail */ |
| 576 | |
| 577 | /* td_thr_validate: make sure a thread handle is real and alive. */ |
| 578 | if ((p_td_thr_validate = dlsym (dlhandle, "td_thr_validate")) == NULL) |
| 579 | return 0; /* fail */ |
| 580 | /* td_thr_get_info: get a bunch of info about a thread. */ |
| 581 | if ((p_td_thr_get_info = dlsym (dlhandle, "td_thr_get_info")) == NULL) |
| 582 | return 0; /* fail */ |
| 583 | /* td_thr_getgregs: get general registers for thread. */ |
| 584 | if ((p_td_thr_getgregs = dlsym (dlhandle, "td_thr_getgregs")) == NULL) |
| 585 | return 0; /* fail */ |
| 586 | /* td_thr_setgregs: set general registers for thread. */ |
| 587 | if ((p_td_thr_setgregs = dlsym (dlhandle, "td_thr_setgregs")) == NULL) |
| 588 | return 0; /* fail */ |
| 589 | /* td_thr_getfpregs: get floating point registers for thread. */ |
| 590 | if ((p_td_thr_getfpregs = dlsym (dlhandle, "td_thr_getfpregs")) == NULL) |
| 591 | return 0; /* fail */ |
| 592 | /* td_thr_setfpregs: set floating point registers for thread. */ |
| 593 | if ((p_td_thr_setfpregs = dlsym (dlhandle, "td_thr_setfpregs")) == NULL) |
| 594 | return 0; /* fail */ |
| 595 | |
| 596 | ret = p_td_init (); |
| 597 | if (ret != TD_OK) |
| 598 | { |
| 599 | warning ("init_thread_db: td_init: %s", thr_err_string (ret)); |
| 600 | return 0; |
| 601 | } |
| 602 | |
| 603 | /* Optional functions: |
| 604 | We can still debug even if the following functions are not found. */ |
| 605 | |
| 606 | /* td_ta_event_addr: get the breakpoint address for specified event. */ |
| 607 | p_td_ta_event_addr = dlsym (dlhandle, "td_ta_event_addr"); |
| 608 | |
| 609 | /* td_ta_event_getmsg: get the next event message for the process. */ |
| 610 | p_td_ta_event_getmsg = dlsym (dlhandle, "td_ta_event_getmsg"); |
| 611 | |
| 612 | /* td_ta_set_event: request notification of an event. */ |
| 613 | p_td_ta_set_event = dlsym (dlhandle, "td_ta_set_event"); |
| 614 | |
| 615 | /* td_thr_event_enable: enable event reporting in a thread. */ |
| 616 | p_td_thr_event_enable = dlsym (dlhandle, "td_thr_event_enable"); |
| 617 | |
| 618 | return 1; /* success */ |
| 619 | } |
| 620 | |
| 621 | /* |
| 622 | * Local utility functions: |
| 623 | */ |
| 624 | |
| 625 | |
| 626 | /* |
| 627 | |
| 628 | LOCAL FUNCTION |
| 629 | |
| 630 | save_inferior_pid - Save inferior_pid on the cleanup list |
| 631 | restore_inferior_pid - Restore inferior_pid from the cleanup list |
| 632 | |
| 633 | SYNOPSIS |
| 634 | |
| 635 | struct cleanup *save_inferior_pid (void); |
| 636 | void restore_inferior_pid (void *saved_pid); |
| 637 | |
| 638 | DESCRIPTION |
| 639 | |
| 640 | These two functions act in unison to restore inferior_pid in |
| 641 | case of an error. |
| 642 | |
| 643 | NOTES |
| 644 | |
| 645 | inferior_pid is a global variable that needs to be changed by many |
| 646 | of these routines before calling functions in procfs.c. In order |
| 647 | to guarantee that inferior_pid gets restored (in case of errors), |
| 648 | you need to call save_inferior_pid before changing it. At the end |
| 649 | of the function, you should invoke do_cleanups to restore it. |
| 650 | |
| 651 | */ |
| 652 | |
| 653 | static struct cleanup * |
| 654 | save_inferior_pid (void) |
| 655 | { |
| 656 | int *saved_pid_ptr; |
| 657 | |
| 658 | saved_pid_ptr = xmalloc (sizeof (int)); |
| 659 | *saved_pid_ptr = inferior_pid; |
| 660 | return make_cleanup (restore_inferior_pid, saved_pid_ptr); |
| 661 | } |
| 662 | |
| 663 | static void |
| 664 | restore_inferior_pid (void *arg) |
| 665 | { |
| 666 | int *saved_pid_ptr = arg; |
| 667 | inferior_pid = *saved_pid_ptr; |
| 668 | free (arg); |
| 669 | } |
| 670 | |
| 671 | /* |
| 672 | |
| 673 | LOCAL FUNCTION |
| 674 | |
| 675 | thr_err_string - Convert a thread_db error code to a string |
| 676 | |
| 677 | SYNOPSIS |
| 678 | |
| 679 | char * thr_err_string (errcode) |
| 680 | |
| 681 | DESCRIPTION |
| 682 | |
| 683 | Return a string description of the thread_db errcode. If errcode |
| 684 | is unknown, then return an <unknown> message. |
| 685 | |
| 686 | */ |
| 687 | |
| 688 | static char * |
| 689 | thr_err_string (td_err_e errcode) |
| 690 | { |
| 691 | static char buf[50]; |
| 692 | |
| 693 | switch (errcode) { |
| 694 | case TD_OK: return "generic 'call succeeded'"; |
| 695 | case TD_ERR: return "generic error"; |
| 696 | case TD_NOTHR: return "no thread to satisfy query"; |
| 697 | case TD_NOSV: return "no sync handle to satisfy query"; |
| 698 | case TD_NOLWP: return "no lwp to satisfy query"; |
| 699 | case TD_BADPH: return "invalid process handle"; |
| 700 | case TD_BADTH: return "invalid thread handle"; |
| 701 | case TD_BADSH: return "invalid synchronization handle"; |
| 702 | case TD_BADTA: return "invalid thread agent"; |
| 703 | case TD_BADKEY: return "invalid key"; |
| 704 | case TD_NOMSG: return "no event message for getmsg"; |
| 705 | case TD_NOFPREGS: return "FPU register set not available"; |
| 706 | case TD_NOLIBTHREAD: return "application not linked with libthread"; |
| 707 | case TD_NOEVENT: return "requested event is not supported"; |
| 708 | case TD_NOCAPAB: return "capability not available"; |
| 709 | case TD_DBERR: return "debugger service failed"; |
| 710 | case TD_NOAPLIC: return "operation not applicable to"; |
| 711 | case TD_NOTSD: return "no thread-specific data for this thread"; |
| 712 | case TD_MALLOC: return "malloc failed"; |
| 713 | case TD_PARTIALREG: return "only part of register set was written/read"; |
| 714 | case TD_NOXREGS: return "X register set not available for this thread"; |
| 715 | default: |
| 716 | sprintf (buf, "unknown thread_db error '%d'", errcode); |
| 717 | return buf; |
| 718 | } |
| 719 | } |
| 720 | |
| 721 | /* |
| 722 | |
| 723 | LOCAL FUNCTION |
| 724 | |
| 725 | thr_state_string - Convert a thread_db state code to a string |
| 726 | |
| 727 | SYNOPSIS |
| 728 | |
| 729 | char *thr_state_string (statecode) |
| 730 | |
| 731 | DESCRIPTION |
| 732 | |
| 733 | Return the thread_db state string associated with statecode. |
| 734 | If statecode is unknown, then return an <unknown> message. |
| 735 | |
| 736 | */ |
| 737 | |
| 738 | static char * |
| 739 | thr_state_string (td_thr_state_e statecode) |
| 740 | { |
| 741 | static char buf[50]; |
| 742 | |
| 743 | switch (statecode) { |
| 744 | case TD_THR_STOPPED: return "stopped by debugger"; |
| 745 | case TD_THR_RUN: return "runnable"; |
| 746 | case TD_THR_ACTIVE: return "active"; |
| 747 | case TD_THR_ZOMBIE: return "zombie"; |
| 748 | case TD_THR_SLEEP: return "sleeping"; |
| 749 | case TD_THR_STOPPED_ASLEEP: return "stopped by debugger AND blocked"; |
| 750 | default: |
| 751 | sprintf (buf, "unknown thread_db state %d", statecode); |
| 752 | return buf; |
| 753 | } |
| 754 | } |
| 755 | |
| 756 | /* |
| 757 | * Local thread/event list. |
| 758 | * This data structure will be used to hold a list of threads and |
| 759 | * pending/deliverable events. |
| 760 | */ |
| 761 | |
| 762 | typedef struct THREADINFO { |
| 763 | thread_t tid; /* thread ID */ |
| 764 | pid_t lid; /* process/lwp ID */ |
| 765 | td_thr_state_e state; /* thread state (a la thread_db) */ |
| 766 | td_thr_type_e type; /* thread type (a la thread_db) */ |
| 767 | int pending; /* true if holding a pending event */ |
| 768 | int status; /* wait status of any interesting event */ |
| 769 | } threadinfo; |
| 770 | |
| 771 | threadinfo * threadlist; |
| 772 | int threadlist_max = 0; /* current size of table */ |
| 773 | int threadlist_top = 0; /* number of threads now in table */ |
| 774 | #define THREADLIST_ALLOC 100 /* chunk size by which to expand table */ |
| 775 | |
| 776 | static threadinfo * |
| 777 | insert_thread (int tid, int lid, td_thr_state_e state, td_thr_type_e type) |
| 778 | { |
| 779 | if (threadlist_top >= threadlist_max) |
| 780 | { |
| 781 | threadlist_max += THREADLIST_ALLOC; |
| 782 | threadlist = realloc (threadlist, |
| 783 | threadlist_max * sizeof (threadinfo)); |
| 784 | if (threadlist == NULL) |
| 785 | return NULL; |
| 786 | } |
| 787 | threadlist[threadlist_top].tid = tid; |
| 788 | threadlist[threadlist_top].lid = lid; |
| 789 | threadlist[threadlist_top].state = state; |
| 790 | threadlist[threadlist_top].type = type; |
| 791 | threadlist[threadlist_top].pending = 0; |
| 792 | threadlist[threadlist_top].status = 0; |
| 793 | |
| 794 | return &threadlist[threadlist_top++]; |
| 795 | } |
| 796 | |
| 797 | static void |
| 798 | empty_threadlist (void) |
| 799 | { |
| 800 | threadlist_top = 0; |
| 801 | } |
| 802 | |
| 803 | static threadinfo * |
| 804 | next_pending_event (void) |
| 805 | { |
| 806 | int i; |
| 807 | |
| 808 | for (i = 0; i < threadlist_top; i++) |
| 809 | if (threadlist[i].pending) |
| 810 | return &threadlist[i]; |
| 811 | |
| 812 | return NULL; |
| 813 | } |
| 814 | |
| 815 | static void |
| 816 | threadlist_iter (int (*func) (), void *data, td_thr_state_e state, |
| 817 | td_thr_type_e type) |
| 818 | { |
| 819 | int i; |
| 820 | |
| 821 | for (i = 0; i < threadlist_top; i++) |
| 822 | if ((state == TD_THR_ANY_STATE || state == threadlist[i].state) && |
| 823 | (type == TD_THR_ANY_TYPE || type == threadlist[i].type)) |
| 824 | if ((*func) (&threadlist[i], data) != 0) |
| 825 | break; |
| 826 | |
| 827 | return; |
| 828 | } |
| 829 | |
| 830 | /* |
| 831 | * Global state |
| 832 | * |
| 833 | * Here we keep state information all collected in one place. |
| 834 | */ |
| 835 | |
| 836 | /* This flag is set when we activate, so that we don't do it twice. |
| 837 | Defined in linux-thread.c and used for inter-target syncronization. */ |
| 838 | extern int using_thread_db; |
| 839 | |
| 840 | /* The process id for which we've stopped. |
| 841 | * This is only set when we actually stop all threads. |
| 842 | * Otherwise it's zero. |
| 843 | */ |
| 844 | static int event_pid; |
| 845 | |
| 846 | /* |
| 847 | * The process id for a new thread to which we've just attached. |
| 848 | * This process needs special handling at resume time. |
| 849 | */ |
| 850 | static int attach_pid; |
| 851 | |
| 852 | |
| 853 | /* |
| 854 | * thread_db event handling: |
| 855 | * |
| 856 | * The mechanism for event notification via the thread_db API. |
| 857 | * These events are implemented as breakpoints. The thread_db |
| 858 | * library gives us an address where we can set a breakpoint. |
| 859 | * When the breakpoint is hit, it represents an event of interest |
| 860 | * such as: |
| 861 | * Thread creation |
| 862 | * Thread death |
| 863 | * Thread reap |
| 864 | */ |
| 865 | |
| 866 | /* Location of the thread creation event breakpoint. The code at this |
| 867 | location in the child process will be called by the pthread library |
| 868 | whenever a new thread is created. By setting a special breakpoint |
| 869 | at this location, GDB can detect when a new thread is created. We |
| 870 | obtain this location via the td_ta_event_addr call. */ |
| 871 | |
| 872 | static CORE_ADDR thread_creation_bkpt_address; |
| 873 | |
| 874 | /* Location of the thread death event breakpoint. The code at this |
| 875 | location in the child process will be called by the pthread library |
| 876 | whenever a thread is destroyed. By setting a special breakpoint at |
| 877 | this location, GDB can detect when a new thread is created. We |
| 878 | obtain this location via the td_ta_event_addr call. */ |
| 879 | |
| 880 | static CORE_ADDR thread_death_bkpt_address; |
| 881 | |
| 882 | /* This function handles the global parts of enabling thread events. |
| 883 | The thread-specific enabling is handled per-thread elsewhere. */ |
| 884 | |
| 885 | static void |
| 886 | enable_thread_event_reporting (td_thragent_t *ta) |
| 887 | { |
| 888 | td_thr_events_t events; |
| 889 | td_notify_t notify; |
| 890 | CORE_ADDR addr; |
| 891 | |
| 892 | if (p_td_ta_set_event == NULL || |
| 893 | p_td_ta_event_addr == NULL || |
| 894 | p_td_ta_event_getmsg == NULL || |
| 895 | p_td_thr_event_enable == NULL) |
| 896 | return; /* can't do thread event reporting without these funcs */ |
| 897 | |
| 898 | /* set process wide mask saying which events we are interested in */ |
| 899 | td_event_emptyset (&events); |
| 900 | td_event_addset (&events, TD_CREATE); |
| 901 | td_event_addset (&events, TD_DEATH); |
| 902 | |
| 903 | if (p_td_ta_set_event (ta, &events) != TD_OK) |
| 904 | { |
| 905 | warning ("unable to set global thread event mask"); |
| 906 | return; |
| 907 | } |
| 908 | |
| 909 | /* Delete previous thread event breakpoints, if any. */ |
| 910 | remove_thread_event_breakpoints (); |
| 911 | |
| 912 | /* create breakpoints -- thread creation and death */ |
| 913 | /* thread creation */ |
| 914 | /* get breakpoint location */ |
| 915 | if (p_td_ta_event_addr (ta, TD_CREATE, ¬ify) != TD_OK) |
| 916 | { |
| 917 | warning ("unable to get location for thread creation breakpoint"); |
| 918 | return; |
| 919 | } |
| 920 | |
| 921 | /* Set up the breakpoint. */ |
| 922 | create_thread_event_breakpoint (notify.u.bptaddr); |
| 923 | |
| 924 | /* Save it's location. */ |
| 925 | thread_creation_bkpt_address = notify.u.bptaddr; |
| 926 | |
| 927 | /* thread death */ |
| 928 | /* get breakpoint location */ |
| 929 | if (p_td_ta_event_addr (ta, TD_DEATH, ¬ify) != TD_OK) |
| 930 | { |
| 931 | warning ("unable to get location for thread death breakpoint"); |
| 932 | return; |
| 933 | } |
| 934 | /* Set up the breakpoint. */ |
| 935 | create_thread_event_breakpoint (notify.u.bptaddr); |
| 936 | |
| 937 | /* Save it's location. */ |
| 938 | thread_death_bkpt_address = notify.u.bptaddr; |
| 939 | } |
| 940 | |
| 941 | /* This function handles the global parts of disabling thread events. |
| 942 | The thread-specific enabling is handled per-thread elsewhere. */ |
| 943 | |
| 944 | static void |
| 945 | disable_thread_event_reporting (td_thragent_t *ta) |
| 946 | { |
| 947 | td_thr_events_t events; |
| 948 | |
| 949 | /* set process wide mask saying we aren't interested in any events */ |
| 950 | td_event_emptyset (&events); |
| 951 | p_td_ta_set_event (main_threadagent, &events); |
| 952 | |
| 953 | /* Delete thread event breakpoints, if any. */ |
| 954 | remove_thread_event_breakpoints (); |
| 955 | thread_creation_bkpt_address = 0; |
| 956 | thread_death_bkpt_address = 0; |
| 957 | } |
| 958 | |
| 959 | /* check_for_thread_event |
| 960 | |
| 961 | if it's a thread event we recognize (currently |
| 962 | we only recognize creation and destruction |
| 963 | events), return 1; else return 0. */ |
| 964 | |
| 965 | |
| 966 | static int |
| 967 | check_for_thread_event (struct target_waitstatus *tws, int event_pid) |
| 968 | { |
| 969 | /* FIXME: to be more efficient, we should keep a static |
| 970 | list of threads, and update it only here (with td_ta_thr_iter). */ |
| 971 | } |
| 972 | |
| 973 | static void |
| 974 | thread_db_push_target (void) |
| 975 | { |
| 976 | /* Called ONLY from thread_db_new_objfile after td_ta_new call succeeds. */ |
| 977 | |
| 978 | /* Push this target vector */ |
| 979 | push_target (&thread_db_ops); |
| 980 | /* Find the underlying process-layer target for calling later. */ |
| 981 | target_beneath = find_target_beneath (&thread_db_ops); |
| 982 | using_thread_db = 1; |
| 983 | /* Turn on thread_db event-reporting API. */ |
| 984 | enable_thread_event_reporting (main_threadagent); |
| 985 | } |
| 986 | |
| 987 | static void |
| 988 | thread_db_unpush_target (void) |
| 989 | { |
| 990 | /* Must be called whenever we remove ourself from the target stack! */ |
| 991 | |
| 992 | using_thread_db = 0; |
| 993 | target_beneath = NULL; |
| 994 | |
| 995 | /* delete local list of threads */ |
| 996 | empty_threadlist (); |
| 997 | /* Turn off the thread_db API. */ |
| 998 | p_td_ta_delete (main_threadagent); |
| 999 | /* Unpush this target vector */ |
| 1000 | unpush_target (&thread_db_ops); |
| 1001 | /* Reset linuxthreads module. */ |
| 1002 | linuxthreads_discard_global_state (); |
| 1003 | } |
| 1004 | |
| 1005 | /* |
| 1006 | * New objfile hook function: |
| 1007 | * Called for each new objfile (image, shared lib) in the target process. |
| 1008 | * |
| 1009 | * The purpose of this function is to detect that the target process |
| 1010 | * is linked with the (appropriate) thread library. So every time a |
| 1011 | * new target shared library is detected, we will call td_ta_new. |
| 1012 | * If it succeeds, we know we have a multi-threaded target process |
| 1013 | * that we can debug using the thread_db API. |
| 1014 | */ |
| 1015 | |
| 1016 | /* |
| 1017 | * new_objfile function: |
| 1018 | * |
| 1019 | * connected to target_new_objfile_hook, this function gets called |
| 1020 | * every time a new binary image is loaded. |
| 1021 | * |
| 1022 | * At each call, we attempt to open the thread_db connection to the |
| 1023 | * child process. If it succeeds, we know we have a libthread process |
| 1024 | * and we can debug it with this target vector. Therefore we push |
| 1025 | * ourself onto the target stack. |
| 1026 | */ |
| 1027 | |
| 1028 | static void (*target_new_objfile_chain) (struct objfile *objfile); |
| 1029 | static int stop_or_attach_thread_callback (const td_thrhandle_t *th, |
| 1030 | void *data); |
| 1031 | static int wait_thread_callback (const td_thrhandle_t *th, |
| 1032 | void *data); |
| 1033 | |
| 1034 | static void |
| 1035 | thread_db_new_objfile (struct objfile *objfile) |
| 1036 | { |
| 1037 | td_err_e ret; |
| 1038 | |
| 1039 | if (using_thread_db) /* libthread already detected, and */ |
| 1040 | goto quit; /* thread target vector activated. */ |
| 1041 | |
| 1042 | if (objfile == NULL) |
| 1043 | goto quit; /* un-interesting object file */ |
| 1044 | |
| 1045 | /* Initialize our "main prochandle" with the main inferior pid. */ |
| 1046 | main_prochandle.pid = PIDGET (inferior_pid); |
| 1047 | |
| 1048 | /* Now attempt to open a thread_db connection to the |
| 1049 | thread library running in the child process. */ |
| 1050 | ret = p_td_ta_new (&main_prochandle, &main_threadagent); |
| 1051 | switch (ret) { |
| 1052 | default: |
| 1053 | warning ("Unexpected error initializing thread_db: %s", |
| 1054 | thr_err_string (ret)); |
| 1055 | break; |
| 1056 | case TD_NOLIBTHREAD: /* expected: no libthread in child process (yet) */ |
| 1057 | break; |
| 1058 | case TD_OK: /* libthread detected in child: we go live now! */ |
| 1059 | thread_db_push_target (); |
| 1060 | event_pid = inferior_pid; /* for resume */ |
| 1061 | |
| 1062 | /* Now stop everyone else, and attach any new threads you find. */ |
| 1063 | p_td_ta_thr_iter (main_threadagent, |
| 1064 | stop_or_attach_thread_callback, |
| 1065 | (void *) 0, |
| 1066 | TD_THR_ANY_STATE, |
| 1067 | TD_THR_LOWEST_PRIORITY, |
| 1068 | TD_SIGNO_MASK, |
| 1069 | TD_THR_ANY_USER_FLAGS); |
| 1070 | |
| 1071 | /* Now go call wait on all the threads you've stopped: |
| 1072 | This allows us to absorb the SIGKILL event, and to make sure |
| 1073 | that the thread knows that it is stopped (Linux peculiarity). */ |
| 1074 | p_td_ta_thr_iter (main_threadagent, |
| 1075 | wait_thread_callback, |
| 1076 | (void *) 0, |
| 1077 | TD_THR_ANY_STATE, |
| 1078 | TD_THR_LOWEST_PRIORITY, |
| 1079 | TD_SIGNO_MASK, |
| 1080 | TD_THR_ANY_USER_FLAGS); |
| 1081 | |
| 1082 | break; |
| 1083 | } |
| 1084 | quit: |
| 1085 | if (target_new_objfile_chain) |
| 1086 | target_new_objfile_chain (objfile); |
| 1087 | } |
| 1088 | |
| 1089 | |
| 1090 | /* |
| 1091 | |
| 1092 | LOCAL FUNCTION |
| 1093 | |
| 1094 | thread_db_alive - test thread for "aliveness" |
| 1095 | |
| 1096 | SYNOPSIS |
| 1097 | |
| 1098 | static bool thread_db_alive (int pid); |
| 1099 | |
| 1100 | DESCRIPTION |
| 1101 | |
| 1102 | returns true if thread still active in inferior. |
| 1103 | |
| 1104 | */ |
| 1105 | |
| 1106 | static int |
| 1107 | thread_db_alive (int pid) |
| 1108 | { |
| 1109 | if (is_thread (pid)) /* user-space (non-kernel) thread */ |
| 1110 | { |
| 1111 | td_thrhandle_t th; |
| 1112 | td_err_e ret; |
| 1113 | |
| 1114 | pid = GET_THREAD (pid); |
| 1115 | if ((ret = p_td_ta_map_id2thr (main_threadagent, pid, &th)) != TD_OK) |
| 1116 | return 0; /* thread not found */ |
| 1117 | if ((ret = p_td_thr_validate (&th)) != TD_OK) |
| 1118 | return 0; /* thread not valid */ |
| 1119 | return 1; /* known thread: return true */ |
| 1120 | } |
| 1121 | else if (target_beneath->to_thread_alive) |
| 1122 | return target_beneath->to_thread_alive (pid); |
| 1123 | else |
| 1124 | return 0; /* default to "not alive" (shouldn't happen anyway) */ |
| 1125 | } |
| 1126 | |
| 1127 | /* |
| 1128 | * get_lwp_from_thread_handle |
| 1129 | */ |
| 1130 | |
| 1131 | static int /* lwpid_t or pid_t */ |
| 1132 | get_lwp_from_thread_handle (td_thrhandle_t *th) |
| 1133 | { |
| 1134 | td_thrinfo_t ti; |
| 1135 | td_err_e ret; |
| 1136 | |
| 1137 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1138 | error ("get_lwp_from_thread_handle: thr_get_info failed: %s", |
| 1139 | thr_err_string (ret)); |
| 1140 | |
| 1141 | return ti.ti_lid; |
| 1142 | } |
| 1143 | |
| 1144 | /* |
| 1145 | * get_lwp_from_thread_id |
| 1146 | */ |
| 1147 | |
| 1148 | static int /* lwpid_t or pid_t */ |
| 1149 | get_lwp_from_thread_id (int tid /* thread_t? */) |
| 1150 | { |
| 1151 | td_thrhandle_t th; |
| 1152 | td_err_e ret; |
| 1153 | |
| 1154 | if ((ret = p_td_ta_map_id2thr (main_threadagent, tid, &th)) != TD_OK) |
| 1155 | error ("get_lwp_from_thread_id: map_id2thr failed: %s", |
| 1156 | thr_err_string (ret)); |
| 1157 | |
| 1158 | return get_lwp_from_thread_handle (&th); |
| 1159 | } |
| 1160 | |
| 1161 | /* |
| 1162 | * pid_to_str has to handle user-space threads. |
| 1163 | * If not a user-space thread, then pass the request on to the |
| 1164 | * underlying stratum if it can handle it: else call normal_pid_to_str. |
| 1165 | */ |
| 1166 | |
| 1167 | static char * |
| 1168 | thread_db_pid_to_str (int pid) |
| 1169 | { |
| 1170 | static char buf[100]; |
| 1171 | td_thrhandle_t th; |
| 1172 | td_thrinfo_t ti; |
| 1173 | td_err_e ret; |
| 1174 | |
| 1175 | if (is_thread (pid)) |
| 1176 | { |
| 1177 | if ((ret = p_td_ta_map_id2thr (main_threadagent, |
| 1178 | GET_THREAD (pid), |
| 1179 | &th)) != TD_OK) |
| 1180 | error ("thread_db: map_id2thr failed: %s", thr_err_string (ret)); |
| 1181 | |
| 1182 | if ((ret = p_td_thr_get_info (&th, &ti)) != TD_OK) |
| 1183 | error ("thread_db: thr_get_info failed: %s", thr_err_string (ret)); |
| 1184 | |
| 1185 | if (ti.ti_state == TD_THR_ACTIVE && |
| 1186 | ti.ti_lid != 0) |
| 1187 | sprintf (buf, "Thread %d (LWP %d)", ti.ti_tid, ti.ti_lid); |
| 1188 | else |
| 1189 | sprintf (buf, "Thread %d (%s)", ti.ti_tid, |
| 1190 | thr_state_string (ti.ti_state)); |
| 1191 | } |
| 1192 | else if (GET_LWP (pid)) |
| 1193 | sprintf (buf, "LWP %d", GET_LWP (pid)); |
| 1194 | else return normal_pid_to_str (pid); |
| 1195 | |
| 1196 | return buf; |
| 1197 | } |
| 1198 | |
| 1199 | /* |
| 1200 | * thread_db target vector functions: |
| 1201 | */ |
| 1202 | |
| 1203 | static void |
| 1204 | thread_db_files_info (struct target_ops *tgt_vector) |
| 1205 | { |
| 1206 | /* This function will be unnecessary in real life. */ |
| 1207 | printf_filtered ("thread_db stratum:\n"); |
| 1208 | target_beneath->to_files_info (tgt_vector); |
| 1209 | } |
| 1210 | |
| 1211 | /* |
| 1212 | * xfer_memory has to munge the inferior_pid before passing the call |
| 1213 | * down to the target layer. |
| 1214 | */ |
| 1215 | |
| 1216 | static int |
| 1217 | thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int dowrite, |
| 1218 | struct target_ops *target) |
| 1219 | { |
| 1220 | struct cleanup *old_chain; |
| 1221 | int ret; |
| 1222 | |
| 1223 | old_chain = save_inferior_pid (); |
| 1224 | |
| 1225 | if (is_thread (inferior_pid) || |
| 1226 | !target_thread_alive (inferior_pid)) |
| 1227 | { |
| 1228 | /* FIXME: use the LID/LWP, so that underlying process layer |
| 1229 | can read memory from specific threads? */ |
| 1230 | inferior_pid = main_prochandle.pid; |
| 1231 | } |
| 1232 | |
| 1233 | ret = target_beneath->to_xfer_memory (memaddr, myaddr, len, |
| 1234 | dowrite, target); |
| 1235 | do_cleanups (old_chain); |
| 1236 | return ret; |
| 1237 | } |
| 1238 | |
| 1239 | /* |
| 1240 | * fetch_registers has to determine if inferior_pid is a user-space thread. |
| 1241 | * If so, we use the thread_db API to get the registers. |
| 1242 | * And if not, we call the underlying process stratum. |
| 1243 | */ |
| 1244 | |
| 1245 | static void |
| 1246 | thread_db_fetch_registers (int regno) |
| 1247 | { |
| 1248 | td_thrhandle_t thandle; |
| 1249 | gdb_prfpregset_t fpregset; |
| 1250 | prgregset_t gregset; |
| 1251 | thread_t thread; |
| 1252 | td_err_e ret; |
| 1253 | |
| 1254 | if (!is_thread (inferior_pid)) /* kernel thread */ |
| 1255 | { /* pass the request on to the target underneath. */ |
| 1256 | target_beneath->to_fetch_registers (regno); |
| 1257 | return; |
| 1258 | } |
| 1259 | |
| 1260 | /* convert inferior_pid into a td_thrhandle_t */ |
| 1261 | |
| 1262 | if ((thread = GET_THREAD (inferior_pid)) == 0) |
| 1263 | error ("fetch_registers: thread == 0"); |
| 1264 | |
| 1265 | if ((ret = p_td_ta_map_id2thr (main_threadagent, thread, &thandle)) != TD_OK) |
| 1266 | error ("fetch_registers: td_ta_map_id2thr: %s", thr_err_string (ret)); |
| 1267 | |
| 1268 | /* Get the integer regs: |
| 1269 | For the sparc, TD_PARTIALREG means that only i0->i7, l0->l7, |
| 1270 | pc and sp are saved (by a thread context switch). */ |
| 1271 | if ((ret = p_td_thr_getgregs (&thandle, gregset)) != TD_OK && |
| 1272 | ret != TD_PARTIALREG) |
| 1273 | error ("fetch_registers: td_thr_getgregs %s", thr_err_string (ret)); |
| 1274 | |
| 1275 | /* And, now the fp regs */ |
| 1276 | if ((ret = p_td_thr_getfpregs (&thandle, &fpregset)) != TD_OK && |
| 1277 | ret != TD_NOFPREGS) |
| 1278 | error ("fetch_registers: td_thr_getfpregs %s", thr_err_string (ret)); |
| 1279 | |
| 1280 | /* Note that we must call supply_{g fp}regset *after* calling the td routines |
| 1281 | because the td routines call ps_lget* which affect the values stored in the |
| 1282 | registers array. */ |
| 1283 | |
| 1284 | supply_gregset (gregset); |
| 1285 | supply_fpregset (&fpregset); |
| 1286 | |
| 1287 | } |
| 1288 | |
| 1289 | /* |
| 1290 | * store_registers has to determine if inferior_pid is a user-space thread. |
| 1291 | * If so, we use the thread_db API to get the registers. |
| 1292 | * And if not, we call the underlying process stratum. |
| 1293 | */ |
| 1294 | |
| 1295 | static void |
| 1296 | thread_db_store_registers (int regno) |
| 1297 | { |
| 1298 | td_thrhandle_t thandle; |
| 1299 | gdb_prfpregset_t fpregset; |
| 1300 | prgregset_t gregset; |
| 1301 | thread_t thread; |
| 1302 | td_err_e ret; |
| 1303 | |
| 1304 | if (!is_thread (inferior_pid)) /* Kernel thread: */ |
| 1305 | { /* pass the request on to the underlying target vector. */ |
| 1306 | target_beneath->to_store_registers (regno); |
| 1307 | return; |
| 1308 | } |
| 1309 | |
| 1310 | /* convert inferior_pid into a td_thrhandle_t */ |
| 1311 | |
| 1312 | if ((thread = GET_THREAD (inferior_pid)) == 0) |
| 1313 | error ("store_registers: thread == 0"); |
| 1314 | |
| 1315 | if ((ret = p_td_ta_map_id2thr (main_threadagent, thread, &thandle)) != TD_OK) |
| 1316 | error ("store_registers: td_ta_map_id2thr %s", thr_err_string (ret)); |
| 1317 | |
| 1318 | if (regno != -1) |
| 1319 | { /* Not writing all the regs */ |
| 1320 | /* save new register value */ |
| 1321 | /* MVS: I don't understand this... */ |
| 1322 | char old_value[REGISTER_SIZE]; |
| 1323 | |
| 1324 | memcpy (old_value, ®isters[REGISTER_BYTE (regno)], REGISTER_SIZE); |
| 1325 | |
| 1326 | if ((ret = p_td_thr_getgregs (&thandle, gregset)) != TD_OK) |
| 1327 | error ("store_registers: td_thr_getgregs %s", thr_err_string (ret)); |
| 1328 | if ((ret = p_td_thr_getfpregs (&thandle, &fpregset)) != TD_OK) |
| 1329 | error ("store_registers: td_thr_getfpregs %s", thr_err_string (ret)); |
| 1330 | |
| 1331 | /* restore new register value */ |
| 1332 | memcpy (®isters[REGISTER_BYTE (regno)], old_value, REGISTER_SIZE); |
| 1333 | |
| 1334 | } |
| 1335 | |
| 1336 | fill_gregset (gregset, regno); |
| 1337 | fill_fpregset (&fpregset, regno); |
| 1338 | |
| 1339 | if ((ret = p_td_thr_setgregs (&thandle, gregset)) != TD_OK) |
| 1340 | error ("store_registers: td_thr_setgregs %s", thr_err_string (ret)); |
| 1341 | if ((ret = p_td_thr_setfpregs (&thandle, &fpregset)) != TD_OK && |
| 1342 | ret != TD_NOFPREGS) |
| 1343 | error ("store_registers: td_thr_setfpregs %s", thr_err_string (ret)); |
| 1344 | } |
| 1345 | |
| 1346 | static void |
| 1347 | handle_new_thread (int tid, /* user thread id */ |
| 1348 | int lid, /* kernel thread id */ |
| 1349 | int verbose) |
| 1350 | { |
| 1351 | int gdb_pid = BUILD_THREAD (tid, main_prochandle.pid); |
| 1352 | int wait_pid, wait_status; |
| 1353 | |
| 1354 | if (verbose) |
| 1355 | printf_filtered ("[New %s]\n", target_pid_to_str (gdb_pid)); |
| 1356 | add_thread (gdb_pid); |
| 1357 | |
| 1358 | if (lid != main_prochandle.pid) |
| 1359 | { |
| 1360 | attach_thread (lid); |
| 1361 | /* According to the Eric Paire model, we now have to send |
| 1362 | the restart signal to the new thread -- however, empirically, |
| 1363 | I do not find that to be necessary. */ |
| 1364 | attach_pid = lid; |
| 1365 | } |
| 1366 | } |
| 1367 | |
| 1368 | static void |
| 1369 | test_for_new_thread (int tid, int lid, int verbose) |
| 1370 | { |
| 1371 | if (!in_thread_list (BUILD_THREAD (tid, main_prochandle.pid))) |
| 1372 | handle_new_thread (tid, lid, verbose); |
| 1373 | } |
| 1374 | |
| 1375 | /* |
| 1376 | * Callback function that gets called once per USER thread |
| 1377 | * (i.e., not kernel) thread by td_ta_thr_iter. |
| 1378 | */ |
| 1379 | |
| 1380 | static int |
| 1381 | find_new_threads_callback (const td_thrhandle_t *th, void *ignored) |
| 1382 | { |
| 1383 | td_thrinfo_t ti; |
| 1384 | td_err_e ret; |
| 1385 | |
| 1386 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1387 | { |
| 1388 | warning ("find_new_threads_callback: %s", thr_err_string (ret)); |
| 1389 | return -1; /* bail out, get_info failed. */ |
| 1390 | } |
| 1391 | |
| 1392 | /* FIXME: |
| 1393 | As things now stand, this should never detect a new thread. |
| 1394 | But if it does, we could be in trouble because we aren't calling |
| 1395 | wait_thread_callback for it. */ |
| 1396 | test_for_new_thread (ti.ti_tid, ti.ti_lid, 0); |
| 1397 | return 0; |
| 1398 | } |
| 1399 | |
| 1400 | /* |
| 1401 | * find_new_threads uses the thread_db iterator function to discover |
| 1402 | * user-space threads. Then if the underlying process stratum has a |
| 1403 | * find_new_threads method, we call that too. |
| 1404 | */ |
| 1405 | |
| 1406 | static void |
| 1407 | thread_db_find_new_threads (void) |
| 1408 | { |
| 1409 | if (inferior_pid == -1) /* FIXME: still necessary? */ |
| 1410 | { |
| 1411 | printf_filtered ("No process.\n"); |
| 1412 | return; |
| 1413 | } |
| 1414 | p_td_ta_thr_iter (main_threadagent, |
| 1415 | find_new_threads_callback, |
| 1416 | (void *) 0, |
| 1417 | TD_THR_ANY_STATE, |
| 1418 | TD_THR_LOWEST_PRIORITY, |
| 1419 | TD_SIGNO_MASK, |
| 1420 | TD_THR_ANY_USER_FLAGS); |
| 1421 | if (target_beneath->to_find_new_threads) |
| 1422 | target_beneath->to_find_new_threads (); |
| 1423 | } |
| 1424 | |
| 1425 | /* |
| 1426 | * Resume all threads, or resume a single thread. |
| 1427 | * If step is true, then single-step the appropriate thread |
| 1428 | * (or single-step inferior_pid, but continue everyone else). |
| 1429 | * If signo is true, then send that signal to at least one thread. |
| 1430 | */ |
| 1431 | |
| 1432 | /* |
| 1433 | * This function is called once for each thread before resuming. |
| 1434 | * It sends continue (no step, and no signal) to each thread except |
| 1435 | * the main thread, and |
| 1436 | * the event thread (the one that stopped at a breakpoint etc.) |
| 1437 | * |
| 1438 | * The event thread is handled separately so that it can be sent |
| 1439 | * the stepping and signal args with which target_resume was called. |
| 1440 | * |
| 1441 | * The main thread is resumed last, so that the thread_db proc_service |
| 1442 | * callbacks will still work during the iterator function. |
| 1443 | */ |
| 1444 | |
| 1445 | static int |
| 1446 | resume_thread_callback (const td_thrhandle_t *th, void *data) |
| 1447 | { |
| 1448 | td_thrinfo_t ti; |
| 1449 | td_err_e ret; |
| 1450 | |
| 1451 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1452 | { |
| 1453 | warning ("resume_thread_callback: %s", thr_err_string (ret)); |
| 1454 | return -1; /* bail out, get_info failed. */ |
| 1455 | } |
| 1456 | /* FIXME: |
| 1457 | As things now stand, this should never detect a new thread. |
| 1458 | But if it does, we could be in trouble because we aren't calling |
| 1459 | wait_thread_callback for it. */ |
| 1460 | test_for_new_thread (ti.ti_tid, ti.ti_lid, 1); |
| 1461 | |
| 1462 | if (ti.ti_lid != main_prochandle.pid && |
| 1463 | ti.ti_lid != event_pid) |
| 1464 | { |
| 1465 | /* Unconditionally continue the thread with no signal. |
| 1466 | Only the event thread will get a signal of any kind. */ |
| 1467 | |
| 1468 | target_beneath->to_resume (ti.ti_lid, 0, 0); |
| 1469 | } |
| 1470 | return 0; |
| 1471 | } |
| 1472 | |
| 1473 | static int |
| 1474 | new_resume_thread_callback (threadinfo *thread, void *data) |
| 1475 | { |
| 1476 | if (thread->lid != event_pid && |
| 1477 | thread->lid != main_prochandle.pid) |
| 1478 | { |
| 1479 | /* Unconditionally continue the thread with no signal (for now). */ |
| 1480 | |
| 1481 | target_beneath->to_resume (thread->lid, 0, 0); |
| 1482 | } |
| 1483 | return 0; |
| 1484 | } |
| 1485 | |
| 1486 | static int last_resume_pid; |
| 1487 | static int last_resume_step; |
| 1488 | static int last_resume_signo; |
| 1489 | |
| 1490 | static void |
| 1491 | thread_db_resume (int pid, int step, enum target_signal signo) |
| 1492 | { |
| 1493 | last_resume_pid = pid; |
| 1494 | last_resume_step = step; |
| 1495 | last_resume_signo = signo; |
| 1496 | |
| 1497 | /* resuming a specific pid? */ |
| 1498 | if (pid != -1) |
| 1499 | { |
| 1500 | if (is_thread (pid)) |
| 1501 | pid = get_lwp_from_thread_id (GET_THREAD (pid)); |
| 1502 | else if (GET_LWP (pid)) |
| 1503 | pid = GET_LWP (pid); |
| 1504 | } |
| 1505 | |
| 1506 | /* Apparently the interpretation of 'pid' is dependent on 'step': |
| 1507 | If step is true, then a specific pid means 'step only this pid'. |
| 1508 | But if step is not true, then pid means 'continue ALL pids, but |
| 1509 | give the signal only to this one'. */ |
| 1510 | if (pid != -1 && step) |
| 1511 | { |
| 1512 | /* FIXME: is this gonna work in all circumstances? */ |
| 1513 | target_beneath->to_resume (pid, step, signo); |
| 1514 | } |
| 1515 | else |
| 1516 | { |
| 1517 | /* 1) Continue all threads except the event thread and the main thread. |
| 1518 | 2) resume the event thread with step and signo. |
| 1519 | 3) If event thread != main thread, continue the main thread. |
| 1520 | |
| 1521 | Note: order of 2 and 3 may need to be reversed. */ |
| 1522 | |
| 1523 | threadlist_iter (new_resume_thread_callback, |
| 1524 | (void *) 0, |
| 1525 | TD_THR_ANY_STATE, |
| 1526 | TD_THR_ANY_TYPE); |
| 1527 | /* now resume event thread, and if necessary also main thread. */ |
| 1528 | if (event_pid) |
| 1529 | { |
| 1530 | target_beneath->to_resume (event_pid, step, signo); |
| 1531 | } |
| 1532 | if (event_pid != main_prochandle.pid) |
| 1533 | { |
| 1534 | target_beneath->to_resume (main_prochandle.pid, 0, 0); |
| 1535 | } |
| 1536 | } |
| 1537 | } |
| 1538 | |
| 1539 | /* All new threads will be attached. |
| 1540 | All previously known threads will be stopped using kill (SIGKILL). */ |
| 1541 | |
| 1542 | static int |
| 1543 | stop_or_attach_thread_callback (const td_thrhandle_t *th, void *data) |
| 1544 | { |
| 1545 | td_thrinfo_t ti; |
| 1546 | td_err_e ret; |
| 1547 | int gdb_pid; |
| 1548 | int on_off = 1; |
| 1549 | |
| 1550 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1551 | { |
| 1552 | warning ("stop_or_attach_thread_callback: %s", thr_err_string (ret)); |
| 1553 | return -1; /* bail out, get_info failed. */ |
| 1554 | } |
| 1555 | |
| 1556 | /* First add it to our internal list. |
| 1557 | We build this list anew at every wait event. */ |
| 1558 | insert_thread (ti.ti_tid, ti.ti_lid, ti.ti_state, ti.ti_type); |
| 1559 | /* Now: if we've already seen it, stop it, else add it and attach it. */ |
| 1560 | gdb_pid = BUILD_THREAD (ti.ti_tid, main_prochandle.pid); |
| 1561 | if (!in_thread_list (gdb_pid)) /* new thread */ |
| 1562 | { |
| 1563 | handle_new_thread (ti.ti_tid, ti.ti_lid, 1); |
| 1564 | /* Enable thread events */ |
| 1565 | if (p_td_thr_event_enable) |
| 1566 | if ((ret = p_td_thr_event_enable (th, on_off)) != TD_OK) |
| 1567 | warning ("stop_or_attach_thread: %s", thr_err_string (ret)); |
| 1568 | } |
| 1569 | else if (ti.ti_lid != event_pid && |
| 1570 | ti.ti_lid != main_prochandle.pid) |
| 1571 | { |
| 1572 | ret = (td_err_e) kill (ti.ti_lid, SIGSTOP); |
| 1573 | } |
| 1574 | |
| 1575 | return 0; |
| 1576 | } |
| 1577 | |
| 1578 | /* |
| 1579 | * Wait for signal N from pid PID. |
| 1580 | * If wait returns any other signals, put them back before returning. |
| 1581 | */ |
| 1582 | |
| 1583 | static void |
| 1584 | wait_for_stop (int pid) |
| 1585 | { |
| 1586 | int i; |
| 1587 | int retpid; |
| 1588 | int status; |
| 1589 | |
| 1590 | /* Array of wait/signal status */ |
| 1591 | /* FIXME: wrong data structure, we need a queue. |
| 1592 | Realtime signals may be delivered more than once. |
| 1593 | And at that, we really can't handle them (see below). */ |
| 1594 | #if defined (NSIG) |
| 1595 | static int wstatus [NSIG]; |
| 1596 | #elif defined (_NSIG) |
| 1597 | static int wstatus [_NSIG]; |
| 1598 | #else |
| 1599 | #error No definition for number of signals! |
| 1600 | #endif |
| 1601 | |
| 1602 | /* clear wait/status list */ |
| 1603 | memset (&wstatus, 0, sizeof (wstatus)); |
| 1604 | |
| 1605 | /* Now look for SIGSTOP event on all threads except event thread. */ |
| 1606 | do { |
| 1607 | errno = 0; |
| 1608 | if (pid == main_prochandle.pid) |
| 1609 | retpid = waitpid (pid, &status, 0); |
| 1610 | else |
| 1611 | retpid = waitpid (pid, &status, __WCLONE); |
| 1612 | |
| 1613 | if (retpid > 0) |
| 1614 | if (WSTOPSIG (status) == SIGSTOP) |
| 1615 | { |
| 1616 | /* Got the SIGSTOP event we're looking for. |
| 1617 | Throw it away, and throw any other events back! */ |
| 1618 | for (i = 0; i < sizeof(wstatus) / sizeof (wstatus[0]); i++) |
| 1619 | if (wstatus[i]) |
| 1620 | if (i != SIGSTOP) |
| 1621 | { |
| 1622 | kill (retpid, i); |
| 1623 | } |
| 1624 | break; /* all done */ |
| 1625 | } |
| 1626 | else |
| 1627 | { |
| 1628 | int signo; |
| 1629 | /* Oops, got an event other than SIGSTOP. |
| 1630 | Save it, and throw it back after we find the SIGSTOP event. */ |
| 1631 | |
| 1632 | /* FIXME (how?) This method is going to fail for realtime |
| 1633 | signals, which cannot be put back simply by using kill. */ |
| 1634 | |
| 1635 | if (WIFEXITED (status)) |
| 1636 | error ("Ack! Thread Exited event. What do I do now???"); |
| 1637 | else if (WIFSTOPPED (status)) |
| 1638 | signo = WSTOPSIG (status); |
| 1639 | else |
| 1640 | signo = WTERMSIG (status); |
| 1641 | |
| 1642 | /* If a thread other than the event thread has hit a GDB |
| 1643 | breakpoint (as opposed to some random trap signal), then |
| 1644 | just arrange for it to hit it again later. Back up the |
| 1645 | PC if necessary. Don't forward the SIGTRAP signal to |
| 1646 | the thread. We will handle the current event, eventually |
| 1647 | we will resume all the threads, and this one will get |
| 1648 | it's breakpoint trap again. |
| 1649 | |
| 1650 | If we do not do this, then we run the risk that the user |
| 1651 | will delete or disable the breakpoint, but the thread will |
| 1652 | have already tripped on it. */ |
| 1653 | |
| 1654 | if (retpid != event_pid && |
| 1655 | signo == SIGTRAP && |
| 1656 | breakpoint_inserted_here_p (read_pc_pid (retpid) - |
| 1657 | DECR_PC_AFTER_BREAK)) |
| 1658 | { |
| 1659 | /* Set the pc to before the trap and DO NOT re-send the signal */ |
| 1660 | if (DECR_PC_AFTER_BREAK) |
| 1661 | write_pc_pid (read_pc_pid (retpid) - DECR_PC_AFTER_BREAK, |
| 1662 | retpid); |
| 1663 | } |
| 1664 | |
| 1665 | /* Since SIGINT gets forwarded to the entire process group |
| 1666 | (in the case where ^C is typed at the tty / console), |
| 1667 | just ignore all SIGINTs from other than the event thread. */ |
| 1668 | else if (retpid != event_pid && signo == SIGINT) |
| 1669 | { /* do nothing. Signal will disappear into oblivion! */ |
| 1670 | ; |
| 1671 | } |
| 1672 | |
| 1673 | else /* This is some random signal other than a breakpoint. */ |
| 1674 | { |
| 1675 | wstatus [signo] = 1; |
| 1676 | } |
| 1677 | child_resume (retpid, 0, TARGET_SIGNAL_0); |
| 1678 | continue; |
| 1679 | } |
| 1680 | |
| 1681 | } while (errno == 0 || errno == EINTR); |
| 1682 | } |
| 1683 | |
| 1684 | /* |
| 1685 | * wait_thread_callback |
| 1686 | * |
| 1687 | * Calls waitpid for each thread, repeatedly if necessary, until |
| 1688 | * SIGSTOP is returned. Afterward, if any other signals were returned |
| 1689 | * by waitpid, return them to the thread's pending queue by calling kill. |
| 1690 | */ |
| 1691 | |
| 1692 | static int |
| 1693 | wait_thread_callback (const td_thrhandle_t *th, void *data) |
| 1694 | { |
| 1695 | td_thrinfo_t ti; |
| 1696 | td_err_e ret; |
| 1697 | |
| 1698 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1699 | { |
| 1700 | warning ("wait_thread_callback: %s", thr_err_string (ret)); |
| 1701 | return -1; /* bail out, get_info failed. */ |
| 1702 | } |
| 1703 | |
| 1704 | /* This callback to act on all threads except the event thread: */ |
| 1705 | if (ti.ti_lid == event_pid || /* no need to wait (no sigstop) */ |
| 1706 | ti.ti_lid == main_prochandle.pid) /* no need to wait (already waited) */ |
| 1707 | return 0; /* don't wait on the event thread. */ |
| 1708 | |
| 1709 | wait_for_stop (ti.ti_lid); |
| 1710 | return 0; /* finished: next thread. */ |
| 1711 | } |
| 1712 | |
| 1713 | static int |
| 1714 | new_wait_thread_callback (threadinfo *thread, void *data) |
| 1715 | { |
| 1716 | /* don't wait on the event thread -- it's already stopped and waited. |
| 1717 | Ditto the main thread. */ |
| 1718 | if (thread->lid != event_pid && |
| 1719 | thread->lid != main_prochandle.pid) |
| 1720 | { |
| 1721 | wait_for_stop (thread->lid); |
| 1722 | } |
| 1723 | return 0; |
| 1724 | } |
| 1725 | |
| 1726 | /* |
| 1727 | * Wait for any thread to stop, by calling the underlying wait method. |
| 1728 | * The PID returned by the underlying target may be a kernel thread, |
| 1729 | * in which case we will want to convert it to the corresponding |
| 1730 | * user-space thread. |
| 1731 | */ |
| 1732 | |
| 1733 | static int |
| 1734 | thread_db_wait (int pid, struct target_waitstatus *ourstatus) |
| 1735 | { |
| 1736 | td_thrhandle_t thandle; |
| 1737 | td_thrinfo_t ti; |
| 1738 | td_err_e ret; |
| 1739 | lwpid_t lwp; |
| 1740 | int retpid; |
| 1741 | int status; |
| 1742 | int save_errno; |
| 1743 | |
| 1744 | /* OK, we're about to wait for an event from the running inferior. |
| 1745 | Make sure we're ignoring the right signals. */ |
| 1746 | |
| 1747 | check_all_signal_numbers (); /* see if magic signals changed. */ |
| 1748 | |
| 1749 | event_pid = 0; |
| 1750 | attach_pid = 0; |
| 1751 | |
| 1752 | /* FIXME: should I do the wait right here inline? */ |
| 1753 | #if 0 |
| 1754 | if (pid == -1) |
| 1755 | lwp = -1; |
| 1756 | else |
| 1757 | lwp = get_lwp_from_thread_id (GET_THREAD (pid)); |
| 1758 | #endif |
| 1759 | |
| 1760 | |
| 1761 | save_errno = linux_child_wait (-1, &retpid, &status); |
| 1762 | store_waitstatus (ourstatus, status); |
| 1763 | |
| 1764 | /* Thread ID is irrelevant if the target process exited. |
| 1765 | FIXME: do I have any killing to do? |
| 1766 | Can I get this event mistakenly from a thread? */ |
| 1767 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
| 1768 | return retpid; |
| 1769 | |
| 1770 | /* OK, we got an event of interest. |
| 1771 | Go stop all threads and look for new ones. |
| 1772 | FIXME: maybe don't do this for the restart signal? Optimization... */ |
| 1773 | event_pid = retpid; |
| 1774 | |
| 1775 | /* If the last call to resume was for a specific thread, then we don't |
| 1776 | need to stop everyone else: they should already be stopped. */ |
| 1777 | if (last_resume_step == 0 || last_resume_pid == -1) |
| 1778 | { |
| 1779 | /* Main thread must be stopped before calling the iterator. */ |
| 1780 | if (retpid != main_prochandle.pid) |
| 1781 | { |
| 1782 | kill (main_prochandle.pid, SIGSTOP); |
| 1783 | wait_for_stop (main_prochandle.pid); |
| 1784 | } |
| 1785 | |
| 1786 | empty_threadlist (); |
| 1787 | /* Now stop everyone else, and attach any new threads you find. */ |
| 1788 | p_td_ta_thr_iter (main_threadagent, |
| 1789 | stop_or_attach_thread_callback, |
| 1790 | (void *) 0, |
| 1791 | TD_THR_ANY_STATE, |
| 1792 | TD_THR_LOWEST_PRIORITY, |
| 1793 | TD_SIGNO_MASK, |
| 1794 | TD_THR_ANY_USER_FLAGS); |
| 1795 | |
| 1796 | /* Now go call wait on all the threads we've stopped: |
| 1797 | This allows us to absorb the SIGKILL event, and to make sure |
| 1798 | that the thread knows that it is stopped (Linux peculiarity). */ |
| 1799 | |
| 1800 | threadlist_iter (new_wait_thread_callback, |
| 1801 | (void *) 0, |
| 1802 | TD_THR_ANY_STATE, |
| 1803 | TD_THR_ANY_TYPE); |
| 1804 | } |
| 1805 | |
| 1806 | /* Convert the kernel thread id to the corresponding thread id. */ |
| 1807 | |
| 1808 | /* If the process layer does not furnish an lwp, |
| 1809 | then perhaps the returned pid IS the lwp... */ |
| 1810 | if ((lwp = GET_LWP (retpid)) == 0) |
| 1811 | lwp = retpid; |
| 1812 | |
| 1813 | if ((ret = p_td_ta_map_lwp2thr (main_threadagent, lwp, &thandle)) != TD_OK) |
| 1814 | return retpid; /* LWP is not mapped onto a user-space thread. */ |
| 1815 | |
| 1816 | if ((ret = p_td_thr_validate (&thandle)) != TD_OK) |
| 1817 | return retpid; /* LWP is not mapped onto a valid thread. */ |
| 1818 | |
| 1819 | if ((ret = p_td_thr_get_info (&thandle, &ti)) != TD_OK) |
| 1820 | { |
| 1821 | warning ("thread_db: thr_get_info failed ('%s')", thr_err_string (ret)); |
| 1822 | return retpid; |
| 1823 | } |
| 1824 | |
| 1825 | retpid = BUILD_THREAD (ti.ti_tid, main_prochandle.pid); |
| 1826 | /* If this is a new user thread, notify GDB about it. */ |
| 1827 | if (!in_thread_list (retpid)) |
| 1828 | { |
| 1829 | printf_filtered ("[New %s]\n", target_pid_to_str (retpid)); |
| 1830 | add_thread (retpid); |
| 1831 | } |
| 1832 | |
| 1833 | #if 0 |
| 1834 | /* Now detect if this is a thread creation/deletion event: */ |
| 1835 | check_for_thread_event (ourstatus, retpid); |
| 1836 | #endif |
| 1837 | return retpid; |
| 1838 | } |
| 1839 | |
| 1840 | /* |
| 1841 | * kill has to call the underlying kill. |
| 1842 | * FIXME: I'm not sure if it's necessary to check inferior_pid any more, |
| 1843 | * but we might need to fix inferior_pid up if it's a user thread. |
| 1844 | */ |
| 1845 | |
| 1846 | static int |
| 1847 | kill_thread_callback (td_thrhandle_t *th, void *data) |
| 1848 | { |
| 1849 | td_thrinfo_t ti; |
| 1850 | td_err_e ret; |
| 1851 | |
| 1852 | /* Fixme: |
| 1853 | For Linux, threads may need to be waited. */ |
| 1854 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1855 | { |
| 1856 | warning ("kill_thread_callback: %s", thr_err_string (ret)); |
| 1857 | return -1; /* bail out, get_info failed. */ |
| 1858 | } |
| 1859 | |
| 1860 | if (ti.ti_lid != main_prochandle.pid) |
| 1861 | { |
| 1862 | kill (ti.ti_lid, SIGKILL); |
| 1863 | } |
| 1864 | return 0; |
| 1865 | } |
| 1866 | |
| 1867 | |
| 1868 | static void thread_db_kill (void) |
| 1869 | { |
| 1870 | int rpid; |
| 1871 | int status; |
| 1872 | |
| 1873 | /* Fixme: |
| 1874 | For Linux, threads may need to be waited. */ |
| 1875 | if (inferior_pid != 0) |
| 1876 | { |
| 1877 | /* Go kill the children first. Save the main thread for last. */ |
| 1878 | p_td_ta_thr_iter (main_threadagent, |
| 1879 | kill_thread_callback, |
| 1880 | (void *) 0, |
| 1881 | TD_THR_ANY_STATE, |
| 1882 | TD_THR_LOWEST_PRIORITY, |
| 1883 | TD_SIGNO_MASK, |
| 1884 | TD_THR_ANY_USER_FLAGS); |
| 1885 | |
| 1886 | /* Turn off thread_db event-reporting API *before* killing the |
| 1887 | main thread, since this operation requires child memory access. |
| 1888 | Can't move this into thread_db_unpush target because then |
| 1889 | detach would not work. */ |
| 1890 | disable_thread_event_reporting (main_threadagent); |
| 1891 | |
| 1892 | inferior_pid = main_prochandle.pid; |
| 1893 | |
| 1894 | /* |
| 1895 | * Since both procfs_kill and ptrace_kill call target_mourn, |
| 1896 | * it should be sufficient for me to call one of them. |
| 1897 | * That will result in my mourn being called, which will both |
| 1898 | * unpush me and call the underlying mourn. |
| 1899 | */ |
| 1900 | target_beneath->to_kill (); |
| 1901 | } |
| 1902 | |
| 1903 | /* Wait for all threads. */ |
| 1904 | /* FIXME: need a universal wait_for_signal func? */ |
| 1905 | do |
| 1906 | { |
| 1907 | rpid = waitpid (-1, &status, __WCLONE | WNOHANG); |
| 1908 | } |
| 1909 | while (rpid > 0 || errno == EINTR); |
| 1910 | |
| 1911 | do |
| 1912 | { |
| 1913 | rpid = waitpid (-1, &status, WNOHANG); |
| 1914 | } |
| 1915 | while (rpid > 0 || errno == EINTR); |
| 1916 | } |
| 1917 | |
| 1918 | /* |
| 1919 | * Mourn has to remove us from the target stack, |
| 1920 | * and then call the underlying mourn. |
| 1921 | */ |
| 1922 | |
| 1923 | static void thread_db_mourn_inferior (void) |
| 1924 | { |
| 1925 | thread_db_unpush_target (); |
| 1926 | target_mourn_inferior (); /* call the underlying mourn */ |
| 1927 | } |
| 1928 | |
| 1929 | /* |
| 1930 | * Detach has to remove us from the target stack, |
| 1931 | * and then call the underlying detach. |
| 1932 | * |
| 1933 | * But first, it has to detach all the cloned threads! |
| 1934 | */ |
| 1935 | |
| 1936 | static int |
| 1937 | detach_thread_callback (td_thrhandle_t *th, void *data) |
| 1938 | { |
| 1939 | /* Called once per thread. */ |
| 1940 | td_thrinfo_t ti; |
| 1941 | td_err_e ret; |
| 1942 | |
| 1943 | if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| 1944 | { |
| 1945 | warning ("detach_thread_callback: %s", thr_err_string (ret)); |
| 1946 | return -1; /* bail out, get_info failed. */ |
| 1947 | } |
| 1948 | |
| 1949 | if (!in_thread_list (BUILD_THREAD (ti.ti_tid, main_prochandle.pid))) |
| 1950 | return 0; /* apparently we don't know this one. */ |
| 1951 | |
| 1952 | /* Save main thread for last, or the iterator will fail! */ |
| 1953 | if (ti.ti_lid != main_prochandle.pid) |
| 1954 | { |
| 1955 | struct cleanup *old_chain; |
| 1956 | int off = 0; |
| 1957 | |
| 1958 | /* Time to detach this thread. |
| 1959 | First disable thread_db event reporting for the thread. */ |
| 1960 | if (p_td_thr_event_enable && |
| 1961 | (ret = p_td_thr_event_enable (th, off)) != TD_OK) |
| 1962 | { |
| 1963 | warning ("detach_thread_callback: %s\n", thr_err_string (ret)); |
| 1964 | return 0; |
| 1965 | } |
| 1966 | |
| 1967 | /* Now cancel any pending SIGTRAPS. FIXME! */ |
| 1968 | |
| 1969 | /* Call underlying detach method. FIXME just detach it. */ |
| 1970 | old_chain = save_inferior_pid (); |
| 1971 | inferior_pid = ti.ti_lid; |
| 1972 | detach (TARGET_SIGNAL_0); |
| 1973 | do_cleanups (old_chain); |
| 1974 | } |
| 1975 | return 0; |
| 1976 | } |
| 1977 | |
| 1978 | static void |
| 1979 | thread_db_detach (char *args, int from_tty) |
| 1980 | { |
| 1981 | td_err_e ret; |
| 1982 | |
| 1983 | if ((ret = p_td_ta_thr_iter (main_threadagent, |
| 1984 | detach_thread_callback, |
| 1985 | (void *) 0, |
| 1986 | TD_THR_ANY_STATE, |
| 1987 | TD_THR_LOWEST_PRIORITY, |
| 1988 | TD_SIGNO_MASK, |
| 1989 | TD_THR_ANY_USER_FLAGS)) |
| 1990 | != TD_OK) |
| 1991 | warning ("detach (thr_iter): %s", thr_err_string (ret)); |
| 1992 | |
| 1993 | /* Turn off thread_db event-reporting API |
| 1994 | (before detaching the main thread) */ |
| 1995 | disable_thread_event_reporting (main_threadagent); |
| 1996 | |
| 1997 | thread_db_unpush_target (); |
| 1998 | |
| 1999 | /* above call nullifies target_beneath, so don't use that! */ |
| 2000 | inferior_pid = PIDGET (inferior_pid); |
| 2001 | target_detach (args, from_tty); |
| 2002 | } |
| 2003 | |
| 2004 | |
| 2005 | /* |
| 2006 | * We never want to actually create the inferior! |
| 2007 | * |
| 2008 | * If this is ever called, it means we were on the target stack |
| 2009 | * when the user said "run". But we don't want to be on the new |
| 2010 | * inferior's target stack until the thread_db / libthread |
| 2011 | * connection is ready to be made. |
| 2012 | * |
| 2013 | * So, what shall we do? |
| 2014 | * Unpush ourselves from the stack, and then invoke |
| 2015 | * find_default_create_inferior, which will invoke the |
| 2016 | * appropriate process_stratum target to do the create. |
| 2017 | */ |
| 2018 | |
| 2019 | static void |
| 2020 | thread_db_create_inferior (char *exec_file, char *allargs, char **env) |
| 2021 | { |
| 2022 | thread_db_unpush_target (); |
| 2023 | find_default_create_inferior (exec_file, allargs, env); |
| 2024 | } |
| 2025 | |
| 2026 | /* |
| 2027 | * Thread_db target vector initializer. |
| 2028 | */ |
| 2029 | |
| 2030 | void |
| 2031 | init_thread_db_ops (void) |
| 2032 | { |
| 2033 | thread_db_ops.to_shortname = "multi-thread"; |
| 2034 | thread_db_ops.to_longname = "multi-threaded child process."; |
| 2035 | thread_db_ops.to_doc = "Threads and pthreads support."; |
| 2036 | thread_db_ops.to_files_info = thread_db_files_info; |
| 2037 | thread_db_ops.to_create_inferior = thread_db_create_inferior; |
| 2038 | thread_db_ops.to_detach = thread_db_detach; |
| 2039 | thread_db_ops.to_wait = thread_db_wait; |
| 2040 | thread_db_ops.to_resume = thread_db_resume; |
| 2041 | thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior; |
| 2042 | thread_db_ops.to_kill = thread_db_kill; |
| 2043 | thread_db_ops.to_xfer_memory = thread_db_xfer_memory; |
| 2044 | thread_db_ops.to_fetch_registers = thread_db_fetch_registers; |
| 2045 | thread_db_ops.to_store_registers = thread_db_store_registers; |
| 2046 | thread_db_ops.to_thread_alive = thread_db_alive; |
| 2047 | thread_db_ops.to_find_new_threads = thread_db_find_new_threads; |
| 2048 | thread_db_ops.to_pid_to_str = thread_db_pid_to_str; |
| 2049 | thread_db_ops.to_stratum = thread_stratum; |
| 2050 | thread_db_ops.to_has_thread_control = tc_schedlock; |
| 2051 | thread_db_ops.to_magic = OPS_MAGIC; |
| 2052 | } |
| 2053 | #endif /* HAVE_STDINT_H */ |
| 2054 | |
| 2055 | /* |
| 2056 | * Module constructor / initializer function. |
| 2057 | * If connection to thread_db dynamic library is successful, |
| 2058 | * then initialize this module's target vectors and the |
| 2059 | * new_objfile hook. |
| 2060 | */ |
| 2061 | |
| 2062 | |
| 2063 | void |
| 2064 | _initialize_thread_db (void) |
| 2065 | { |
| 2066 | #ifdef HAVE_STDINT_H /* stub out entire module, leave initializer empty */ |
| 2067 | if (init_thread_db_library ()) |
| 2068 | { |
| 2069 | init_thread_db_ops (); |
| 2070 | add_target (&thread_db_ops); |
| 2071 | /* |
| 2072 | * Hook up to the new_objfile event. |
| 2073 | * If someone is already there, arrange for him to be called |
| 2074 | * after we are. |
| 2075 | */ |
| 2076 | target_new_objfile_chain = target_new_objfile_hook; |
| 2077 | target_new_objfile_hook = thread_db_new_objfile; |
| 2078 | } |
| 2079 | #endif /* HAVE_STDINT_H */ |
| 2080 | } |
| 2081 | |