gdbserver/linux-low.h

   1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
   2    Copyright (C) 2002-2020 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef GDBSERVER_LINUX_LOW_H
  20 #define GDBSERVER_LINUX_LOW_H
  21
  22 #include "nat/linux-nat.h"
  23 #include "nat/gdb_thread_db.h"
  24 #include <signal.h>
  25
  26 #include "gdbthread.h"
  27 #include "gdb_proc_service.h"
  28
  29 /* Included for ptrace type definitions.  */
  30 #include "nat/linux-ptrace.h"
  31 #include "target/waitstatus.h" /* For enum target_stop_reason.  */
  32 #include "tracepoint.h"
  33
  34 #define PTRACE_XFER_TYPE long
  35
  36 #ifdef HAVE_LINUX_REGSETS
  37 typedef void (*regset_fill_func) (struct regcache *, void *);
  38 typedef void (*regset_store_func) (struct regcache *, const void *);
  39 enum regset_type {
  40   GENERAL_REGS,
  41   FP_REGS,
  42   EXTENDED_REGS,
  43   OPTIONAL_REGS, /* Do not error if the regset cannot be accessed.  */
  44 };
  45
  46 /* The arch's regsets array initializer must be terminated with a NULL
  47    regset.  */
  48 #define NULL_REGSET \
  49   { 0, 0, 0, -1, (enum regset_type) -1, NULL, NULL }
  50
  51 struct regset_info
  52 {
  53   int get_request, set_request;
  54   /* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
  55      argument and the 4th argument should be "const struct iovec *".  */
  56   int nt_type;
  57   int size;
  58   enum regset_type type;
  59   regset_fill_func fill_function;
  60   regset_store_func store_function;
  61 };
  62
  63 /* Aggregation of all the supported regsets of a given
  64    architecture/mode.  */
  65
  66 struct regsets_info
  67 {
  68   /* The regsets array.  */
  69   struct regset_info *regsets;
  70
  71   /* The number of regsets in the REGSETS array.  */
  72   int num_regsets;
  73
  74   /* If we get EIO on a regset, do not try it again.  Note the set of
  75      supported regsets may depend on processor mode on biarch
  76      machines.  This is a (lazily allocated) array holding one boolean
  77      byte (0/1) per regset, with each element corresponding to the
  78      regset in the REGSETS array above at the same offset.  */
  79   char *disabled_regsets;
  80 };
  81
  82 #endif
  83
  84 /* Mapping between the general-purpose registers in `struct user'
  85    format and GDB's register array layout.  */
  86
  87 struct usrregs_info
  88 {
  89   /* The number of registers accessible.  */
  90   int num_regs;
  91
  92   /* The registers map.  */
  93   int *regmap;
  94 };
  95
  96 /* All info needed to access an architecture/mode's registers.  */
  97
  98 struct regs_info
  99 {
 100   /* Regset support bitmap: 1 for registers that are transferred as a part
 101      of a regset, 0 for ones that need to be handled individually.  This
 102      can be NULL if all registers are transferred with regsets or regsets
 103      are not supported.  */
 104   unsigned char *regset_bitmap;
 105
 106   /* Info used when accessing registers with PTRACE_PEEKUSER /
 107      PTRACE_POKEUSER.  This can be NULL if all registers are
 108      transferred with regsets  .*/
 109   struct usrregs_info *usrregs;
 110
 111 #ifdef HAVE_LINUX_REGSETS
 112   /* Info used when accessing registers with regsets.  */
 113   struct regsets_info *regsets_info;
 114 #endif
 115 };
 116
 117 struct process_info_private
 118 {
 119   /* Arch-specific additions.  */
 120   struct arch_process_info *arch_private;
 121
 122   /* libthread_db-specific additions.  Not NULL if this process has loaded
 123      thread_db, and it is active.  */
 124   struct thread_db *thread_db;
 125
 126   /* &_r_debug.  0 if not yet determined.  -1 if no PT_DYNAMIC in Phdrs.  */
 127   CORE_ADDR r_debug;
 128 };
 129
 130 struct lwp_info;
 131
 132 struct linux_target_ops
 133 {
 134   /* Architecture-specific setup.  */
 135   void (*arch_setup) (void);
 136
 137   const struct regs_info *(*regs_info) (void);
 138   int (*cannot_fetch_register) (int);
 139
 140   /* Returns 0 if we can store the register, 1 if we can not
 141      store the register, and 2 if failure to store the register
 142      is acceptable.  */
 143   int (*cannot_store_register) (int);
 144
 145   /* Hook to fetch a register in some non-standard way.  Used for
 146      example by backends that have read-only registers with hardcoded
 147      values (e.g., IA64's gr0/fr0/fr1).  Returns true if register
 148      REGNO was supplied, false if not, and we should fallback to the
 149      standard ptrace methods.  */
 150   int (*fetch_register) (struct regcache *regcache, int regno);
 151
 152   CORE_ADDR (*get_pc) (struct regcache *regcache);
 153   void (*set_pc) (struct regcache *regcache, CORE_ADDR newpc);
 154
 155   /* See target.h for details.  */
 156   int (*breakpoint_kind_from_pc) (CORE_ADDR *pcptr);
 157
 158   /* See target.h for details.  */
 159   const gdb_byte *(*sw_breakpoint_from_kind) (int kind, int *size);
 160
 161   /* Find the next possible PCs after the current instruction executes.  */
 162   std::vector<CORE_ADDR> (*get_next_pcs) (struct regcache *regcache);
 163
 164   int decr_pc_after_break;
 165   int (*breakpoint_at) (CORE_ADDR pc);
 166
 167   /* Breakpoint and watchpoint related functions.  See target.h for
 168      comments.  */
 169   int (*supports_z_point_type) (char z_type);
 170   int (*insert_point) (enum raw_bkpt_type type, CORE_ADDR addr,
 171                        int size, struct raw_breakpoint *bp);
 172   int (*remove_point) (enum raw_bkpt_type type, CORE_ADDR addr,
 173                        int size, struct raw_breakpoint *bp);
 174
 175   int (*stopped_by_watchpoint) (void);
 176   CORE_ADDR (*stopped_data_address) (void);
 177
 178   /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
 179      for registers smaller than an xfer unit).  */
 180   void (*collect_ptrace_register) (struct regcache *regcache,
 181                                    int regno, char *buf);
 182   void (*supply_ptrace_register) (struct regcache *regcache,
 183                                   int regno, const char *buf);
 184
 185   /* Hook to convert from target format to ptrace format and back.
 186      Returns true if any conversion was done; false otherwise.
 187      If DIRECTION is 1, then copy from INF to NATIVE.
 188      If DIRECTION is 0, copy from NATIVE to INF.  */
 189   int (*siginfo_fixup) (siginfo_t *native, gdb_byte *inf, int direction);
 190
 191   /* Hook to call when a new process is created or attached to.
 192      If extra per-process architecture-specific data is needed,
 193      allocate it here.  */
 194   struct arch_process_info * (*new_process) (void);
 195
 196   /* Hook to call when a process is being deleted.  If extra per-process
 197      architecture-specific data is needed, delete it here.  */
 198   void (*delete_process) (struct arch_process_info *info);
 199
 200   /* Hook to call when a new thread is detected.
 201      If extra per-thread architecture-specific data is needed,
 202      allocate it here.  */
 203   void (*new_thread) (struct lwp_info *);
 204
 205   /* Hook to call when a thread is being deleted.  If extra per-thread
 206      architecture-specific data is needed, delete it here.  */
 207   void (*delete_thread) (struct arch_lwp_info *);
 208
 209   /* Hook to call, if any, when a new fork is attached.  */
 210   void (*new_fork) (struct process_info *parent, struct process_info *child);
 211
 212   /* Hook to call prior to resuming a thread.  */
 213   void (*prepare_to_resume) (struct lwp_info *);
 214
 215   /* Hook to support target specific qSupported.  */
 216   void (*process_qsupported) (char **, int count);
 217
 218   /* Returns true if the low target supports tracepoints.  */
 219   int (*supports_tracepoints) (void);
 220
 221   /* Fill ADDRP with the thread area address of LWPID.  Returns 0 on
 222      success, -1 on failure.  */
 223   int (*get_thread_area) (int lwpid, CORE_ADDR *addrp);
 224
 225   /* Install a fast tracepoint jump pad.  See target.h for
 226      comments.  */
 227   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 228                                            CORE_ADDR collector,
 229                                            CORE_ADDR lockaddr,
 230                                            ULONGEST orig_size,
 231                                            CORE_ADDR *jump_entry,
 232                                            CORE_ADDR *trampoline,
 233                                            ULONGEST *trampoline_size,
 234                                            unsigned char *jjump_pad_insn,
 235                                            ULONGEST *jjump_pad_insn_size,
 236                                            CORE_ADDR *adjusted_insn_addr,
 237                                            CORE_ADDR *adjusted_insn_addr_end,
 238                                            char *err);
 239
 240   /* Return the bytecode operations vector for the current inferior.
 241      Returns NULL if bytecode compilation is not supported.  */
 242   struct emit_ops *(*emit_ops) (void);
 243
 244   /* Return the minimum length of an instruction that can be safely overwritten
 245      for use as a fast tracepoint.  */
 246   int (*get_min_fast_tracepoint_insn_len) (void);
 247
 248   /* Returns true if the low target supports range stepping.  */
 249   int (*supports_range_stepping) (void);
 250
 251   /* See target.h.  */
 252   int (*breakpoint_kind_from_current_state) (CORE_ADDR *pcptr);
 253
 254   /* See target.h.  */
 255   int (*supports_hardware_single_step) (void);
 256
 257   /* Fill *SYSNO with the syscall nr trapped.  Only to be called when
 258      inferior is stopped due to SYSCALL_SIGTRAP.  */
 259   void (*get_syscall_trapinfo) (struct regcache *regcache, int *sysno);
 260
 261   /* See target.h.  */
 262   int (*get_ipa_tdesc_idx) (void);
 263 };
 264
 265 extern struct linux_target_ops the_low_target;
 266
 267 /* Target ops definitions for a Linux target.  */
 268
 269 class linux_process_target : public process_target
 270 {
 271 public:
 272
 273   int create_inferior (const char *program,
 274                        const std::vector<char *> &program_args) override;
 275
 276   void post_create_inferior () override;
 277
 278   int attach (unsigned long pid) override;
 279
 280   int kill (process_info *proc) override;
 281
 282   int detach (process_info *proc) override;
 283
 284   void mourn (process_info *proc) override;
 285
 286   void join (int pid) override;
 287
 288   bool thread_alive (ptid_t pid) override;
 289
 290   void resume (thread_resume *resume_info, size_t n) override;
 291
 292   ptid_t wait (ptid_t ptid, target_waitstatus *status,
 293                int options) override;
 294
 295   void fetch_registers (regcache *regcache, int regno) override;
 296
 297   void store_registers (regcache *regcache, int regno) override;
 298
 299   int prepare_to_access_memory () override;
 300
 301   void done_accessing_memory () override;
 302
 303   int read_memory (CORE_ADDR memaddr, unsigned char *myaddr,
 304                    int len) override;
 305
 306   int write_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
 307                     int len) override;
 308
 309   void look_up_symbols () override;
 310
 311   void request_interrupt () override;
 312
 313   bool supports_read_auxv () override;
 314
 315   int read_auxv (CORE_ADDR offset, unsigned char *myaddr,
 316                  unsigned int len) override;
 317
 318   bool supports_z_point_type (char z_type) override;
 319
 320   int insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
 321                     int size, raw_breakpoint *bp) override;
 322
 323   int remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
 324                     int size, raw_breakpoint *bp) override;
 325
 326   bool stopped_by_sw_breakpoint () override;
 327
 328   bool supports_stopped_by_sw_breakpoint () override;
 329
 330   bool stopped_by_hw_breakpoint () override;
 331
 332   bool supports_stopped_by_hw_breakpoint () override;
 333
 334   bool supports_hardware_single_step () override;
 335
 336   bool stopped_by_watchpoint () override;
 337
 338   CORE_ADDR stopped_data_address () override;
 339
 340   bool supports_read_offsets () override;
 341
 342   int read_offsets (CORE_ADDR *text, CORE_ADDR *data) override;
 343
 344   bool supports_get_tls_address () override;
 345
 346   int get_tls_address (thread_info *thread, CORE_ADDR offset,
 347                        CORE_ADDR load_module, CORE_ADDR *address) override;
 348
 349   bool supports_qxfer_osdata () override;
 350
 351   int qxfer_osdata (const char *annex, unsigned char *readbuf,
 352                     unsigned const char *writebuf,
 353                     CORE_ADDR offset, int len) override;
 354
 355   bool supports_qxfer_siginfo () override;
 356
 357   int qxfer_siginfo (const char *annex, unsigned char *readbuf,
 358                      unsigned const char *writebuf,
 359                      CORE_ADDR offset, int len) override;
 360
 361   bool supports_non_stop () override;
 362
 363   bool async (bool enable) override;
 364
 365   int start_non_stop (bool enable) override;
 366
 367   bool supports_multi_process () override;
 368
 369   bool supports_fork_events () override;
 370
 371   bool supports_vfork_events () override;
 372
 373   bool supports_exec_events () override;
 374
 375   void handle_new_gdb_connection () override;
 376
 377   int handle_monitor_command (char *mon) override;
 378
 379   int core_of_thread (ptid_t ptid) override;
 380
 381 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
 382   bool supports_read_loadmap () override;
 383
 384   int read_loadmap (const char *annex, CORE_ADDR offset,
 385                     unsigned char *myaddr, unsigned int len) override;
 386 #endif
 387
 388   void process_qsupported (char **features, int count) override;
 389
 390   bool supports_tracepoints () override;
 391
 392   CORE_ADDR read_pc (regcache *regcache) override;
 393
 394   void write_pc (regcache *regcache, CORE_ADDR pc) override;
 395
 396   bool supports_thread_stopped () override;
 397
 398   bool thread_stopped (thread_info *thread) override;
 399
 400   void pause_all (bool freeze) override;
 401
 402   void unpause_all (bool unfreeze) override;
 403
 404   void stabilize_threads () override;
 405
 406   bool supports_fast_tracepoints () override;
 407
 408   int install_fast_tracepoint_jump_pad (CORE_ADDR tpoint,
 409                                         CORE_ADDR tpaddr,
 410                                         CORE_ADDR collector,
 411                                         CORE_ADDR lockaddr,
 412                                         ULONGEST orig_size,
 413                                         CORE_ADDR *jump_entry,
 414                                         CORE_ADDR *trampoline,
 415                                         ULONGEST *trampoline_size,
 416                                         unsigned char *jjump_pad_insn,
 417                                         ULONGEST *jjump_pad_insn_size,
 418                                         CORE_ADDR *adjusted_insn_addr,
 419                                         CORE_ADDR *adjusted_insn_addr_end,
 420                                         char *err) override;
 421
 422   int get_min_fast_tracepoint_insn_len () override;
 423
 424   struct emit_ops *emit_ops () override;
 425
 426   bool supports_disable_randomization () override;
 427
 428   bool supports_qxfer_libraries_svr4 () override;
 429
 430   int qxfer_libraries_svr4 (const char *annex,
 431                             unsigned char *readbuf,
 432                             unsigned const char *writebuf,
 433                             CORE_ADDR offset, int len) override;
 434
 435   bool supports_agent () override;
 436
 437 #ifdef HAVE_LINUX_BTRACE
 438   btrace_target_info *enable_btrace (ptid_t ptid,
 439                                      const btrace_config *conf) override;
 440
 441   int disable_btrace (btrace_target_info *tinfo) override;
 442
 443   int read_btrace (btrace_target_info *tinfo, buffer *buf,
 444                    enum btrace_read_type type) override;
 445
 446   int read_btrace_conf (const btrace_target_info *tinfo,
 447                         buffer *buf) override;
 448 #endif
 449
 450   bool supports_range_stepping () override;
 451
 452   bool supports_pid_to_exec_file () override;
 453
 454   char *pid_to_exec_file (int pid) override;
 455
 456   bool supports_multifs () override;
 457
 458   int multifs_open (int pid, const char *filename, int flags,
 459                     mode_t mode) override;
 460
 461   int multifs_unlink (int pid, const char *filename) override;
 462
 463   ssize_t multifs_readlink (int pid, const char *filename, char *buf,
 464                             size_t bufsiz) override;
 465
 466   int breakpoint_kind_from_pc (CORE_ADDR *pcptr) override;
 467
 468   const gdb_byte *sw_breakpoint_from_kind (int kind, int *size) override;
 469
 470   int breakpoint_kind_from_current_state (CORE_ADDR *pcptr) override;
 471
 472   const char *thread_name (ptid_t thread) override;
 473
 474 #if USE_THREAD_DB
 475   bool thread_handle (ptid_t ptid, gdb_byte **handle,
 476                       int *handle_len) override;
 477 #endif
 478
 479   bool supports_software_single_step () override;
 480 };
 481
 482 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
 483 #define get_lwp_thread(lwp) ((lwp)->thread)
 484
 485 /* This struct is recorded in the target_data field of struct thread_info.
 486
 487    On linux ``all_threads'' is keyed by the LWP ID, which we use as the
 488    GDB protocol representation of the thread ID.  Threads also have
 489    a "process ID" (poorly named) which is (presently) the same as the
 490    LWP ID.
 491
 492    There is also ``all_processes'' is keyed by the "overall process ID",
 493    which GNU/Linux calls tgid, "thread group ID".  */
 494
 495 struct lwp_info
 496 {
 497   /* Backlink to the parent object.  */
 498   struct thread_info *thread;
 499
 500   /* If this flag is set, the next SIGSTOP will be ignored (the
 501      process will be immediately resumed).  This means that either we
 502      sent the SIGSTOP to it ourselves and got some other pending event
 503      (so the SIGSTOP is still pending), or that we stopped the
 504      inferior implicitly via PTRACE_ATTACH and have not waited for it
 505      yet.  */
 506   int stop_expected;
 507
 508   /* When this is true, we shall not try to resume this thread, even
 509      if last_resume_kind isn't resume_stop.  */
 510   int suspended;
 511
 512   /* If this flag is set, the lwp is known to be stopped right now (stop
 513      event already received in a wait()).  */
 514   int stopped;
 515
 516   /* Signal whether we are in a SYSCALL_ENTRY or
 517      in a SYSCALL_RETURN event.
 518      Values:
 519      - TARGET_WAITKIND_SYSCALL_ENTRY
 520      - TARGET_WAITKIND_SYSCALL_RETURN */
 521   enum target_waitkind syscall_state;
 522
 523   /* When stopped is set, the last wait status recorded for this lwp.  */
 524   int last_status;
 525
 526   /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
 527      this LWP's last event, to pass to GDB without any further
 528      processing.  This is used to store extended ptrace event
 529      information or exit status until it can be reported to GDB.  */
 530   struct target_waitstatus waitstatus;
 531
 532   /* A pointer to the fork child/parent relative.  Valid only while
 533      the parent fork event is not reported to higher layers.  Used to
 534      avoid wildcard vCont actions resuming a fork child before GDB is
 535      notified about the parent's fork event.  */
 536   struct lwp_info *fork_relative;
 537
 538   /* When stopped is set, this is where the lwp last stopped, with
 539      decr_pc_after_break already accounted for.  If the LWP is
 540      running, this is the address at which the lwp was resumed.  */
 541   CORE_ADDR stop_pc;
 542
 543   /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
 544      been reported.  */
 545   int status_pending_p;
 546   int status_pending;
 547
 548   /* The reason the LWP last stopped, if we need to track it
 549      (breakpoint, watchpoint, etc.)  */
 550   enum target_stop_reason stop_reason;
 551
 552   /* On architectures where it is possible to know the data address of
 553      a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
 554      contains such data address.  Only valid if STOPPED_BY_WATCHPOINT
 555      is true.  */
 556   CORE_ADDR stopped_data_address;
 557
 558   /* If this is non-zero, it is a breakpoint to be reinserted at our next
 559      stop (SIGTRAP stops only).  */
 560   CORE_ADDR bp_reinsert;
 561
 562   /* If this flag is set, the last continue operation at the ptrace
 563      level on this process was a single-step.  */
 564   int stepping;
 565
 566   /* Range to single step within.  This is a copy of the step range
 567      passed along the last resume request.  See 'struct
 568      thread_resume'.  */
 569   CORE_ADDR step_range_start;   /* Inclusive */
 570   CORE_ADDR step_range_end;     /* Exclusive */
 571
 572   /* If this flag is set, we need to set the event request flags the
 573      next time we see this LWP stop.  */
 574   int must_set_ptrace_flags;
 575
 576   /* If this is non-zero, it points to a chain of signals which need to
 577      be delivered to this process.  */
 578   struct pending_signals *pending_signals;
 579
 580   /* A link used when resuming.  It is initialized from the resume request,
 581      and then processed and cleared in linux_resume_one_lwp.  */
 582   struct thread_resume *resume;
 583
 584   /* Information bout this lwp's fast tracepoint collection status (is it
 585      currently stopped in the jump pad, and if so, before or at/after the
 586      relocated instruction).  Normally, we won't care about this, but we will
 587      if a signal arrives to this lwp while it is collecting.  */
 588   fast_tpoint_collect_result collecting_fast_tracepoint;
 589
 590   /* If this is non-zero, it points to a chain of signals which need
 591      to be reported to GDB.  These were deferred because the thread
 592      was doing a fast tracepoint collect when they arrived.  */
 593   struct pending_signals *pending_signals_to_report;
 594
 595   /* When collecting_fast_tracepoint is first found to be 1, we insert
 596      a exit-jump-pad-quickly breakpoint.  This is it.  */
 597   struct breakpoint *exit_jump_pad_bkpt;
 598
 599 #ifdef USE_THREAD_DB
 600   int thread_known;
 601   /* The thread handle, used for e.g. TLS access.  Only valid if
 602      THREAD_KNOWN is set.  */
 603   td_thrhandle_t th;
 604
 605   /* The pthread_t handle.  */
 606   thread_t thread_handle;
 607 #endif
 608
 609   /* Arch-specific additions.  */
 610   struct arch_lwp_info *arch_private;
 611 };
 612
 613 int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);
 614
 615 /* Attach to PTID.  Returns 0 on success, non-zero otherwise (an
 616    errno).  */
 617 int linux_attach_lwp (ptid_t ptid);
 618
 619 struct lwp_info *find_lwp_pid (ptid_t ptid);
 620 /* For linux_stop_lwp see nat/linux-nat.h.  */
 621
 622 #ifdef HAVE_LINUX_REGSETS
 623 void initialize_regsets_info (struct regsets_info *regsets_info);
 624 #endif
 625
 626 void initialize_low_arch (void);
 627
 628 void linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc);
 629 CORE_ADDR linux_get_pc_32bit (struct regcache *regcache);
 630
 631 void linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc);
 632 CORE_ADDR linux_get_pc_64bit (struct regcache *regcache);
 633
 634 /* From thread-db.c  */
 635 int thread_db_init (void);
 636 void thread_db_detach (struct process_info *);
 637 void thread_db_mourn (struct process_info *);
 638 int thread_db_handle_monitor_command (char *);
 639 int thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
 640                                CORE_ADDR load_module, CORE_ADDR *address);
 641 int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp);
 642
 643 /* Called from linux-low.c when a clone event is detected.  Upon entry,
 644    both the clone and the parent should be stopped.  This function does
 645    whatever is required have the clone under thread_db's control.  */
 646
 647 void thread_db_notice_clone (struct thread_info *parent_thr, ptid_t child_ptid);
 648
 649 bool thread_db_thread_handle (ptid_t ptid, gdb_byte **handle, int *handle_len);
 650
 651 extern int have_ptrace_getregset;
 652
 653 /* Search for the value with type MATCH in the auxv vector with
 654    entries of length WORDSIZE bytes.  If found, store the value in
 655    *VALP and return 1.  If not found or if there is an error, return
 656    0.  */
 657
 658 int linux_get_auxv (int wordsize, CORE_ADDR match,
 659                     CORE_ADDR *valp);
 660
 661 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
 662    WORDSIZE.  If no entry was found, return zero.  */
 663
 664 CORE_ADDR linux_get_hwcap (int wordsize);
 665
 666 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
 667    WORDSIZE.  If no entry was found, return zero.  */
 668
 669 CORE_ADDR linux_get_hwcap2 (int wordsize);
 670
 671 #endif /* GDBSERVER_LINUX_LOW_H */