gdbserver/target.cc

   1 /* Target operations for the remote server for GDB.
   2    Copyright (C) 2002-2022 Free Software Foundation, Inc.
   3
   4    Contributed by MontaVista Software.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "server.h"
  22 #include "tracepoint.h"
  23 #include "gdbsupport/byte-vector.h"
  24 #include "hostio.h"
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27 #include <sys/types.h>
  28 #include <sys/stat.h>
  29
  30 process_stratum_target *the_target;
  31
  32 int
  33 set_desired_thread ()
  34 {
  35   client_state &cs = get_client_state ();
  36   thread_info *found = find_thread_ptid (cs.general_thread);
  37
  38   switch_to_thread (found);
  39   return (current_thread != NULL);
  40 }
  41
  42 int
  43 read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
  44 {
  45   /* At the time of writing, GDB only sends write packets with LEN==0,
  46      not read packets (see comment in target_write_memory), but it
  47      doesn't hurt to prevent problems if it ever does, or we're
  48      connected to some client other than GDB that does.  */
  49   if (len == 0)
  50     return 0;
  51
  52   int res = the_target->read_memory (memaddr, myaddr, len);
  53   check_mem_read (memaddr, myaddr, len);
  54   return res;
  55 }
  56
  57 /* See target/target.h.  */
  58
  59 int
  60 target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
  61 {
  62   return read_inferior_memory (memaddr, myaddr, len);
  63 }
  64
  65 /* See target/target.h.  */
  66
  67 int
  68 target_read_uint32 (CORE_ADDR memaddr, uint32_t *result)
  69 {
  70   return read_inferior_memory (memaddr, (gdb_byte *) result, sizeof (*result));
  71 }
  72
  73 /* See target/target.h.  */
  74
  75 int
  76 target_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
  77                      ssize_t len)
  78 {
  79   /* GDB may send X packets with LEN==0, for probing packet support.
  80      If we let such a request go through, then buffer.data() below may
  81      return NULL, which may confuse target implementations.  Handle it
  82      here to avoid lower levels having to care about this case.  */
  83   if (len == 0)
  84     return 0;
  85
  86   /* Make a copy of the data because check_mem_write may need to
  87      update it.  */
  88   gdb::byte_vector buffer (myaddr, myaddr + len);
  89   check_mem_write (memaddr, buffer.data (), myaddr, len);
  90   return the_target->write_memory (memaddr, buffer.data (), len);
  91 }
  92
  93 ptid_t
  94 mywait (ptid_t ptid, struct target_waitstatus *ourstatus,
  95         target_wait_flags options, int connected_wait)
  96 {
  97   ptid_t ret;
  98
  99   if (connected_wait)
 100     server_waiting = 1;
 101
 102   ret = target_wait (ptid, ourstatus, options);
 103
 104   /* We don't expose _LOADED events to gdbserver core.  See the
 105      `dlls_changed' global.  */
 106   if (ourstatus->kind () == TARGET_WAITKIND_LOADED)
 107     ourstatus->set_stopped (GDB_SIGNAL_0);
 108
 109   /* If GDB is connected through TCP/serial, then GDBserver will most
 110      probably be running on its own terminal/console, so it's nice to
 111      print there why is GDBserver exiting.  If however, GDB is
 112      connected through stdio, then there's no need to spam the GDB
 113      console with this -- the user will already see the exit through
 114      regular GDB output, in that same terminal.  */
 115   if (!remote_connection_is_stdio ())
 116     {
 117       if (ourstatus->kind () == TARGET_WAITKIND_EXITED)
 118         fprintf (stderr,
 119                  "\nChild exited with status %d\n", ourstatus->exit_status ());
 120       else if (ourstatus->kind () == TARGET_WAITKIND_SIGNALLED)
 121         fprintf (stderr, "\nChild terminated with signal = 0x%x (%s)\n",
 122                  gdb_signal_to_host (ourstatus->sig ()),
 123                  gdb_signal_to_name (ourstatus->sig ()));
 124     }
 125
 126   if (connected_wait)
 127     server_waiting = 0;
 128
 129   return ret;
 130 }
 131
 132 /* See target/target.h.  */
 133
 134 void
 135 target_stop_and_wait (ptid_t ptid)
 136 {
 137   struct target_waitstatus status;
 138   bool was_non_stop = non_stop;
 139   struct thread_resume resume_info;
 140
 141   resume_info.thread = ptid;
 142   resume_info.kind = resume_stop;
 143   resume_info.sig = GDB_SIGNAL_0;
 144   the_target->resume (&resume_info, 1);
 145
 146   non_stop = true;
 147   mywait (ptid, &status, 0, 0);
 148   non_stop = was_non_stop;
 149 }
 150
 151 /* See target/target.h.  */
 152
 153 ptid_t
 154 target_wait (ptid_t ptid, struct target_waitstatus *status,
 155              target_wait_flags options)
 156 {
 157   return the_target->wait (ptid, status, options);
 158 }
 159
 160 /* See target/target.h.  */
 161
 162 void
 163 target_mourn_inferior (ptid_t ptid)
 164 {
 165   the_target->mourn (find_process_pid (ptid.pid ()));
 166 }
 167
 168 /* See target/target.h.  */
 169
 170 void
 171 target_continue_no_signal (ptid_t ptid)
 172 {
 173   struct thread_resume resume_info;
 174
 175   resume_info.thread = ptid;
 176   resume_info.kind = resume_continue;
 177   resume_info.sig = GDB_SIGNAL_0;
 178   the_target->resume (&resume_info, 1);
 179 }
 180
 181 /* See target/target.h.  */
 182
 183 void
 184 target_continue (ptid_t ptid, enum gdb_signal signal)
 185 {
 186   struct thread_resume resume_info;
 187
 188   resume_info.thread = ptid;
 189   resume_info.kind = resume_continue;
 190   resume_info.sig = gdb_signal_to_host (signal);
 191   the_target->resume (&resume_info, 1);
 192 }
 193
 194 /* See target/target.h.  */
 195
 196 int
 197 target_supports_multi_process (void)
 198 {
 199   return the_target->supports_multi_process ();
 200 }
 201
 202 void
 203 set_target_ops (process_stratum_target *target)
 204 {
 205   the_target = target;
 206 }
 207
 208 /* Convert pid to printable format.  */
 209
 210 std::string
 211 target_pid_to_str (ptid_t ptid)
 212 {
 213   if (ptid == minus_one_ptid)
 214     return string_printf("<all threads>");
 215   else if (ptid == null_ptid)
 216     return string_printf("<null thread>");
 217   else if (ptid.tid () != 0)
 218     return string_printf("Thread %d.0x%s",
 219                          ptid.pid (),
 220                          phex_nz (ptid.tid (), sizeof (ULONGEST)));
 221   else if (ptid.lwp () != 0)
 222     return string_printf("LWP %d.%ld",
 223                          ptid.pid (), ptid.lwp ());
 224   else
 225     return string_printf("Process %d",
 226                          ptid.pid ());
 227 }
 228
 229 int
 230 kill_inferior (process_info *proc)
 231 {
 232   gdb_agent_about_to_close (proc->pid);
 233
 234   return the_target->kill (proc);
 235 }
 236
 237 /* Define it.  */
 238
 239 target_terminal_state target_terminal::m_terminal_state
 240   = target_terminal_state::is_ours;
 241
 242 /* See target/target.h.  */
 243
 244 void
 245 target_terminal::init ()
 246 {
 247   /* Placeholder needed because of fork_inferior.  Not necessary on
 248      GDBserver.  */
 249 }
 250
 251 /* See target/target.h.  */
 252
 253 void
 254 target_terminal::inferior ()
 255 {
 256   /* Placeholder needed because of fork_inferior.  Not necessary on
 257      GDBserver.  */
 258 }
 259
 260 /* See target/target.h.  */
 261
 262 void
 263 target_terminal::ours ()
 264 {
 265   /* Placeholder needed because of fork_inferior.  Not necessary on
 266      GDBserver.  */
 267 }
 268
 269 /* See target/target.h.  */
 270
 271 void
 272 target_terminal::ours_for_output (void)
 273 {
 274   /* Placeholder.  */
 275 }
 276
 277 /* See target/target.h.  */
 278
 279 void
 280 target_terminal::info (const char *arg, int from_tty)
 281 {
 282   /* Placeholder.  */
 283 }
 284
 285 /* Default implementations of target ops.
 286    See target.h for definitions.  */
 287
 288 void
 289 process_stratum_target::post_create_inferior ()
 290 {
 291   /* Nop.  */
 292 }
 293
 294 void
 295 process_stratum_target::look_up_symbols ()
 296 {
 297   /* Nop.  */
 298 }
 299
 300 bool
 301 process_stratum_target::supports_read_auxv ()
 302 {
 303   return false;
 304 }
 305
 306 int
 307 process_stratum_target::read_auxv (CORE_ADDR offset, unsigned char *myaddr,
 308                                    unsigned int len)
 309 {
 310   gdb_assert_not_reached ("target op read_auxv not supported");
 311 }
 312
 313 bool
 314 process_stratum_target::supports_z_point_type (char z_type)
 315 {
 316   return false;
 317 }
 318
 319 int
 320 process_stratum_target::insert_point (enum raw_bkpt_type type,
 321                                       CORE_ADDR addr,
 322                                       int size, raw_breakpoint *bp)
 323 {
 324   return 1;
 325 }
 326
 327 int
 328 process_stratum_target::remove_point (enum raw_bkpt_type type,
 329                                       CORE_ADDR addr,
 330                                       int size, raw_breakpoint *bp)
 331 {
 332   return 1;
 333 }
 334
 335 bool
 336 process_stratum_target::stopped_by_sw_breakpoint ()
 337 {
 338   return false;
 339 }
 340
 341 bool
 342 process_stratum_target::supports_stopped_by_sw_breakpoint ()
 343 {
 344   return false;
 345 }
 346
 347 bool
 348 process_stratum_target::stopped_by_hw_breakpoint ()
 349 {
 350   return false;
 351 }
 352
 353 bool
 354 process_stratum_target::supports_stopped_by_hw_breakpoint ()
 355 {
 356   return false;
 357 }
 358
 359 bool
 360 process_stratum_target::supports_hardware_single_step ()
 361 {
 362   return false;
 363 }
 364
 365 bool
 366 process_stratum_target::stopped_by_watchpoint ()
 367 {
 368   return false;
 369 }
 370
 371 CORE_ADDR
 372 process_stratum_target::stopped_data_address ()
 373 {
 374   return 0;
 375 }
 376
 377 bool
 378 process_stratum_target::supports_read_offsets ()
 379 {
 380   return false;
 381 }
 382
 383 bool
 384 process_stratum_target::supports_memory_tagging ()
 385 {
 386   return false;
 387 }
 388
 389 bool
 390 process_stratum_target::fetch_memtags (CORE_ADDR address, size_t len,
 391                                        gdb::byte_vector &tags, int type)
 392 {
 393   gdb_assert_not_reached ("target op fetch_memtags not supported");
 394 }
 395
 396 bool
 397 process_stratum_target::store_memtags (CORE_ADDR address, size_t len,
 398                                        const gdb::byte_vector &tags, int type)
 399 {
 400   gdb_assert_not_reached ("target op store_memtags not supported");
 401 }
 402
 403 int
 404 process_stratum_target::read_offsets (CORE_ADDR *text, CORE_ADDR *data)
 405 {
 406   gdb_assert_not_reached ("target op read_offsets not supported");
 407 }
 408
 409 bool
 410 process_stratum_target::supports_get_tls_address ()
 411 {
 412   return false;
 413 }
 414
 415 int
 416 process_stratum_target::get_tls_address (thread_info *thread,
 417                                          CORE_ADDR offset,
 418                                          CORE_ADDR load_module,
 419                                          CORE_ADDR *address)
 420 {
 421   gdb_assert_not_reached ("target op get_tls_address not supported");
 422 }
 423
 424 bool
 425 process_stratum_target::supports_qxfer_osdata ()
 426 {
 427   return false;
 428 }
 429
 430 int
 431 process_stratum_target::qxfer_osdata (const char *annex,
 432                                       unsigned char *readbuf,
 433                                       unsigned const char *writebuf,
 434                                       CORE_ADDR offset, int len)
 435 {
 436   gdb_assert_not_reached ("target op qxfer_osdata not supported");
 437 }
 438
 439 bool
 440 process_stratum_target::supports_qxfer_siginfo ()
 441 {
 442   return false;
 443 }
 444
 445 int
 446 process_stratum_target::qxfer_siginfo (const char *annex,
 447                                        unsigned char *readbuf,
 448                                        unsigned const char *writebuf,
 449                                        CORE_ADDR offset, int len)
 450 {
 451   gdb_assert_not_reached ("target op qxfer_siginfo not supported");
 452 }
 453
 454 bool
 455 process_stratum_target::supports_non_stop ()
 456 {
 457   return false;
 458 }
 459
 460 bool
 461 process_stratum_target::async (bool enable)
 462 {
 463   return false;
 464 }
 465
 466 int
 467 process_stratum_target::start_non_stop (bool enable)
 468 {
 469   if (enable)
 470     return -1;
 471   else
 472     return 0;
 473 }
 474
 475 bool
 476 process_stratum_target::supports_multi_process ()
 477 {
 478   return false;
 479 }
 480
 481 bool
 482 process_stratum_target::supports_fork_events ()
 483 {
 484   return false;
 485 }
 486
 487 bool
 488 process_stratum_target::supports_vfork_events ()
 489 {
 490   return false;
 491 }
 492
 493 bool
 494 process_stratum_target::supports_exec_events ()
 495 {
 496   return false;
 497 }
 498
 499 void
 500 process_stratum_target::handle_new_gdb_connection ()
 501 {
 502   /* Nop.  */
 503 }
 504
 505 int
 506 process_stratum_target::handle_monitor_command (char *mon)
 507 {
 508   return 0;
 509 }
 510
 511 int
 512 process_stratum_target::core_of_thread (ptid_t ptid)
 513 {
 514   return -1;
 515 }
 516
 517 bool
 518 process_stratum_target::supports_read_loadmap ()
 519 {
 520   return false;
 521 }
 522
 523 int
 524 process_stratum_target::read_loadmap (const char *annex,
 525                                       CORE_ADDR offset,
 526                                       unsigned char *myaddr,
 527                                       unsigned int len)
 528 {
 529   gdb_assert_not_reached ("target op read_loadmap not supported");
 530 }
 531
 532 void
 533 process_stratum_target::process_qsupported
 534   (gdb::array_view<const char * const> features)
 535 {
 536   /* Nop.  */
 537 }
 538
 539 bool
 540 process_stratum_target::supports_tracepoints ()
 541 {
 542   return false;
 543 }
 544
 545 CORE_ADDR
 546 process_stratum_target::read_pc (regcache *regcache)
 547 {
 548   gdb_assert_not_reached ("process_target::read_pc: Unable to find PC");
 549 }
 550
 551 void
 552 process_stratum_target::write_pc (regcache *regcache, CORE_ADDR pc)
 553 {
 554   gdb_assert_not_reached ("process_target::write_pc: Unable to update PC");
 555 }
 556
 557 bool
 558 process_stratum_target::supports_thread_stopped ()
 559 {
 560   return false;
 561 }
 562
 563 bool
 564 process_stratum_target::thread_stopped (thread_info *thread)
 565 {
 566   gdb_assert_not_reached ("target op thread_stopped not supported");
 567 }
 568
 569 bool
 570 process_stratum_target::supports_get_tib_address ()
 571 {
 572   return false;
 573 }
 574
 575 int
 576 process_stratum_target::get_tib_address (ptid_t ptid, CORE_ADDR *address)
 577 {
 578   gdb_assert_not_reached ("target op get_tib_address not supported");
 579 }
 580
 581 void
 582 process_stratum_target::pause_all (bool freeze)
 583 {
 584   /* Nop.  */
 585 }
 586
 587 void
 588 process_stratum_target::unpause_all (bool unfreeze)
 589 {
 590   /* Nop.  */
 591 }
 592
 593 void
 594 process_stratum_target::stabilize_threads ()
 595 {
 596   /* Nop.  */
 597 }
 598
 599 bool
 600 process_stratum_target::supports_fast_tracepoints ()
 601 {
 602   return false;
 603 }
 604
 605 int
 606 process_stratum_target::install_fast_tracepoint_jump_pad
 607   (CORE_ADDR tpoint, CORE_ADDR tpaddr, CORE_ADDR collector,
 608    CORE_ADDR lockaddr, ULONGEST orig_size, CORE_ADDR *jump_entry,
 609    CORE_ADDR *trampoline, ULONGEST *trampoline_size,
 610    unsigned char *jjump_pad_insn, ULONGEST *jjump_pad_insn_size,
 611    CORE_ADDR *adjusted_insn_addr, CORE_ADDR *adjusted_insn_addr_end,
 612    char *err)
 613 {
 614   gdb_assert_not_reached ("target op install_fast_tracepoint_jump_pad "
 615                           "not supported");
 616 }
 617
 618 int
 619 process_stratum_target::get_min_fast_tracepoint_insn_len ()
 620 {
 621   return 0;
 622 }
 623
 624 struct emit_ops *
 625 process_stratum_target::emit_ops ()
 626 {
 627   return nullptr;
 628 }
 629
 630 bool
 631 process_stratum_target::supports_disable_randomization ()
 632 {
 633   return false;
 634 }
 635
 636 bool
 637 process_stratum_target::supports_qxfer_libraries_svr4 ()
 638 {
 639   return false;
 640 }
 641
 642 int
 643 process_stratum_target::qxfer_libraries_svr4 (const char *annex,
 644                                               unsigned char *readbuf,
 645                                               unsigned const char *writebuf,
 646                                               CORE_ADDR offset, int len)
 647 {
 648   gdb_assert_not_reached ("target op qxfer_libraries_svr4 not supported");
 649 }
 650
 651 bool
 652 process_stratum_target::supports_agent ()
 653 {
 654   return false;
 655 }
 656
 657 btrace_target_info *
 658 process_stratum_target::enable_btrace (thread_info *tp,
 659                                        const btrace_config *conf)
 660 {
 661   error (_("Target does not support branch tracing."));
 662 }
 663
 664 int
 665 process_stratum_target::disable_btrace (btrace_target_info *tinfo)
 666 {
 667   error (_("Target does not support branch tracing."));
 668 }
 669
 670 int
 671 process_stratum_target::read_btrace (btrace_target_info *tinfo,
 672                              buffer *buffer,
 673                              enum btrace_read_type type)
 674 {
 675   error (_("Target does not support branch tracing."));
 676 }
 677
 678 int
 679 process_stratum_target::read_btrace_conf (const btrace_target_info *tinfo,
 680                                           buffer *buffer)
 681 {
 682   error (_("Target does not support branch tracing."));
 683 }
 684
 685 bool
 686 process_stratum_target::supports_range_stepping ()
 687 {
 688   return false;
 689 }
 690
 691 bool
 692 process_stratum_target::supports_pid_to_exec_file ()
 693 {
 694   return false;
 695 }
 696
 697 const char *
 698 process_stratum_target::pid_to_exec_file (int pid)
 699 {
 700   gdb_assert_not_reached ("target op pid_to_exec_file not supported");
 701 }
 702
 703 bool
 704 process_stratum_target::supports_multifs ()
 705 {
 706   return false;
 707 }
 708
 709 int
 710 process_stratum_target::multifs_open (int pid, const char *filename,
 711                                       int flags, mode_t mode)
 712 {
 713   return open (filename, flags, mode);
 714 }
 715
 716 int
 717 process_stratum_target::multifs_unlink (int pid, const char *filename)
 718 {
 719   return unlink (filename);
 720 }
 721
 722 ssize_t
 723 process_stratum_target::multifs_readlink (int pid, const char *filename,
 724                                           char *buf, size_t bufsiz)
 725 {
 726   return readlink (filename, buf, bufsiz);
 727 }
 728
 729 int
 730 process_stratum_target::breakpoint_kind_from_pc (CORE_ADDR *pcptr)
 731 {
 732   /* The default behavior is to use the size of a breakpoint as the
 733      kind.  */
 734   int size = 0;
 735   sw_breakpoint_from_kind (0, &size);
 736   return size;
 737 }
 738
 739 int
 740 process_stratum_target::breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
 741 {
 742   return breakpoint_kind_from_pc (pcptr);
 743 }
 744
 745 const char *
 746 process_stratum_target::thread_name (ptid_t thread)
 747 {
 748   return nullptr;
 749 }
 750
 751 bool
 752 process_stratum_target::thread_handle (ptid_t ptid, gdb_byte **handle,
 753                                        int *handle_len)
 754 {
 755   return false;
 756 }
 757
 758 thread_info *
 759 process_stratum_target::thread_pending_parent (thread_info *thread)
 760 {
 761   return nullptr;
 762 }
 763
 764 thread_info *
 765 process_stratum_target::thread_pending_child (thread_info *thread)
 766 {
 767   return nullptr;
 768 }
 769
 770 bool
 771 process_stratum_target::supports_software_single_step ()
 772 {
 773   return false;
 774 }
 775
 776 bool
 777 process_stratum_target::supports_catch_syscall ()
 778 {
 779   return false;
 780 }
 781
 782 int
 783 process_stratum_target::get_ipa_tdesc_idx ()
 784 {
 785   return 0;
 786 }