gdb/gdbserver/target.h

   1 /* Target operations for the remote server for GDB.
   2    Copyright (C) 2002-2015 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 #ifndef TARGET_H
  22 #define TARGET_H
  23
  24 #include "target/target.h"
  25 #include "target/resume.h"
  26 #include "target/wait.h"
  27 #include "target/waitstatus.h"
  28 #include "mem-break.h"
  29 #include "btrace-common.h"
  30
  31 struct emit_ops;
  32 struct buffer;
  33 struct process_info;
  34
  35 /* This structure describes how to resume a particular thread (or all
  36    threads) based on the client's request.  If thread is -1, then this
  37    entry applies to all threads.  These are passed around as an
  38    array.  */
  39
  40 struct thread_resume
  41 {
  42   ptid_t thread;
  43
  44   /* How to "resume".  */
  45   enum resume_kind kind;
  46
  47   /* If non-zero, send this signal when we resume, or to stop the
  48      thread.  If stopping a thread, and this is 0, the target should
  49      stop the thread however it best decides to (e.g., SIGSTOP on
  50      linux; SuspendThread on win32).  This is a host signal value (not
  51      enum gdb_signal).  */
  52   int sig;
  53
  54   /* Range to single step within.  Valid only iff KIND is resume_step.
  55
  56      Single-step once, and then continuing stepping as long as the
  57      thread stops in this range.  (If the range is empty
  58      [STEP_RANGE_START == STEP_RANGE_END], then this is a single-step
  59      request.)  */
  60   CORE_ADDR step_range_start;   /* Inclusive */
  61   CORE_ADDR step_range_end;     /* Exclusive */
  62 };
  63
  64 struct target_ops
  65 {
  66   /* Start a new process.
  67
  68      PROGRAM is a path to the program to execute.
  69      ARGS is a standard NULL-terminated array of arguments,
  70      to be passed to the inferior as ``argv''.
  71
  72      Returns the new PID on success, -1 on failure.  Registers the new
  73      process with the process list.  */
  74
  75   int (*create_inferior) (char *program, char **args);
  76
  77   /* Attach to a running process.
  78
  79      PID is the process ID to attach to, specified by the user
  80      or a higher layer.
  81
  82      Returns -1 if attaching is unsupported, 0 on success, and calls
  83      error() otherwise.  */
  84
  85   int (*attach) (unsigned long pid);
  86
  87   /* Kill inferior PID.  Return -1 on failure, and 0 on success.  */
  88
  89   int (*kill) (int pid);
  90
  91   /* Detach from inferior PID. Return -1 on failure, and 0 on
  92      success.  */
  93
  94   int (*detach) (int pid);
  95
  96   /* The inferior process has died.  Do what is right.  */
  97
  98   void (*mourn) (struct process_info *proc);
  99
 100   /* Wait for inferior PID to exit.  */
 101   void (*join) (int pid);
 102
 103   /* Return 1 iff the thread with process ID PID is alive.  */
 104
 105   int (*thread_alive) (ptid_t pid);
 106
 107   /* Resume the inferior process.  */
 108
 109   void (*resume) (struct thread_resume *resume_info, size_t n);
 110
 111   /* Wait for the inferior process or thread to change state.  Store
 112      status through argument pointer STATUS.
 113
 114      PTID = -1 to wait for any pid to do something, PTID(pid,0,0) to
 115      wait for any thread of process pid to do something.  Return ptid
 116      of child, or -1 in case of error; store status through argument
 117      pointer STATUS.  OPTIONS is a bit set of options defined as
 118      TARGET_W* above.  If options contains TARGET_WNOHANG and there's
 119      no child stop to report, return is
 120      null_ptid/TARGET_WAITKIND_IGNORE.  */
 121
 122   ptid_t (*wait) (ptid_t ptid, struct target_waitstatus *status, int options);
 123
 124   /* Fetch registers from the inferior process.
 125
 126      If REGNO is -1, fetch all registers; otherwise, fetch at least REGNO.  */
 127
 128   void (*fetch_registers) (struct regcache *regcache, int regno);
 129
 130   /* Store registers to the inferior process.
 131
 132      If REGNO is -1, store all registers; otherwise, store at least REGNO.  */
 133
 134   void (*store_registers) (struct regcache *regcache, int regno);
 135
 136   /* Prepare to read or write memory from the inferior process.
 137      Targets use this to do what is necessary to get the state of the
 138      inferior such that it is possible to access memory.
 139
 140      This should generally only be called from client facing routines,
 141      such as gdb_read_memory/gdb_write_memory, or the GDB breakpoint
 142      insertion routine.
 143
 144      Like `read_memory' and `write_memory' below, returns 0 on success
 145      and errno on failure.  */
 146
 147   int (*prepare_to_access_memory) (void);
 148
 149   /* Undo the effects of prepare_to_access_memory.  */
 150
 151   void (*done_accessing_memory) (void);
 152
 153   /* Read memory from the inferior process.  This should generally be
 154      called through read_inferior_memory, which handles breakpoint shadowing.
 155
 156      Read LEN bytes at MEMADDR into a buffer at MYADDR.
 157
 158      Returns 0 on success and errno on failure.  */
 159
 160   int (*read_memory) (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 161
 162   /* Write memory to the inferior process.  This should generally be
 163      called through write_inferior_memory, which handles breakpoint shadowing.
 164
 165      Write LEN bytes from the buffer at MYADDR to MEMADDR.
 166
 167      Returns 0 on success and errno on failure.  */
 168
 169   int (*write_memory) (CORE_ADDR memaddr, const unsigned char *myaddr,
 170                        int len);
 171
 172   /* Query GDB for the values of any symbols we're interested in.
 173      This function is called whenever we receive a "qSymbols::"
 174      query, which corresponds to every time more symbols (might)
 175      become available.  NULL if we aren't interested in any
 176      symbols.  */
 177
 178   void (*look_up_symbols) (void);
 179
 180   /* Send an interrupt request to the inferior process,
 181      however is appropriate.  */
 182
 183   void (*request_interrupt) (void);
 184
 185   /* Read auxiliary vector data from the inferior process.
 186
 187      Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 188
 189   int (*read_auxv) (CORE_ADDR offset, unsigned char *myaddr,
 190                     unsigned int len);
 191
 192   /* Returns true if GDB Z breakpoint type TYPE is supported, false
 193      otherwise.  The type is coded as follows:
 194        '0' - software-breakpoint
 195        '1' - hardware-breakpoint
 196        '2' - write watchpoint
 197        '3' - read watchpoint
 198        '4' - access watchpoint
 199   */
 200   int (*supports_z_point_type) (char z_type);
 201
 202   /* Insert and remove a break or watchpoint.
 203      Returns 0 on success, -1 on failure and 1 on unsupported.  */
 204
 205   int (*insert_point) (enum raw_bkpt_type type, CORE_ADDR addr,
 206                        int size, struct raw_breakpoint *bp);
 207   int (*remove_point) (enum raw_bkpt_type type, CORE_ADDR addr,
 208                        int size, struct raw_breakpoint *bp);
 209
 210   /* Returns 1 if the target stopped because it executed a software
 211      breakpoint instruction, 0 otherwise.  */
 212   int (*stopped_by_sw_breakpoint) (void);
 213
 214   /* Returns true if the target knows whether a trap was caused by a
 215      SW breakpoint triggering.  */
 216   int (*supports_stopped_by_sw_breakpoint) (void);
 217
 218   /* Returns 1 if the target stopped for a hardware breakpoint.  */
 219   int (*stopped_by_hw_breakpoint) (void);
 220
 221   /* Returns true if the target knows whether a trap was caused by a
 222      HW breakpoint triggering.  */
 223   int (*supports_stopped_by_hw_breakpoint) (void);
 224
 225   /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise.  */
 226
 227   int (*stopped_by_watchpoint) (void);
 228
 229   /* Returns the address associated with the watchpoint that hit, if any;
 230      returns 0 otherwise.  */
 231
 232   CORE_ADDR (*stopped_data_address) (void);
 233
 234   /* Reports the text, data offsets of the executable.  This is
 235      needed for uclinux where the executable is relocated during load
 236      time.  */
 237
 238   int (*read_offsets) (CORE_ADDR *text, CORE_ADDR *data);
 239
 240   /* Fetch the address associated with a specific thread local storage
 241      area, determined by the specified THREAD, OFFSET, and LOAD_MODULE.
 242      Stores it in *ADDRESS and returns zero on success; otherwise returns
 243      an error code.  A return value of -1 means this system does not
 244      support the operation.  */
 245
 246   int (*get_tls_address) (struct thread_info *thread, CORE_ADDR offset,
 247                           CORE_ADDR load_module, CORE_ADDR *address);
 248
 249    /* Read/Write from/to spufs using qXfer packets.  */
 250   int (*qxfer_spu) (const char *annex, unsigned char *readbuf,
 251                     unsigned const char *writebuf, CORE_ADDR offset, int len);
 252
 253   /* Fill BUF with an hostio error packet representing the last hostio
 254      error.  */
 255   void (*hostio_last_error) (char *buf);
 256
 257   /* Read/Write OS data using qXfer packets.  */
 258   int (*qxfer_osdata) (const char *annex, unsigned char *readbuf,
 259                        unsigned const char *writebuf, CORE_ADDR offset,
 260                        int len);
 261
 262   /* Read/Write extra signal info.  */
 263   int (*qxfer_siginfo) (const char *annex, unsigned char *readbuf,
 264                         unsigned const char *writebuf,
 265                         CORE_ADDR offset, int len);
 266
 267   int (*supports_non_stop) (void);
 268
 269   /* Enables async target events.  Returns the previous enable
 270      state.  */
 271   int (*async) (int enable);
 272
 273   /* Switch to non-stop (1) or all-stop (0) mode.  Return 0 on
 274      success, -1 otherwise.  */
 275   int (*start_non_stop) (int);
 276
 277   /* Returns true if the target supports multi-process debugging.  */
 278   int (*supports_multi_process) (void);
 279
 280   /* If not NULL, target-specific routine to process monitor command.
 281      Returns 1 if handled, or 0 to perform default processing.  */
 282   int (*handle_monitor_command) (char *);
 283
 284   /* Returns the core given a thread, or -1 if not known.  */
 285   int (*core_of_thread) (ptid_t);
 286
 287   /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 288   int (*read_loadmap) (const char *annex, CORE_ADDR offset,
 289                        unsigned char *myaddr, unsigned int len);
 290
 291   /* Target specific qSupported support.  */
 292   void (*process_qsupported) (const char *);
 293
 294   /* Return 1 if the target supports tracepoints, 0 (or leave the
 295      callback NULL) otherwise.  */
 296   int (*supports_tracepoints) (void);
 297
 298   /* Read PC from REGCACHE.  */
 299   CORE_ADDR (*read_pc) (struct regcache *regcache);
 300
 301   /* Write PC to REGCACHE.  */
 302   void (*write_pc) (struct regcache *regcache, CORE_ADDR pc);
 303
 304   /* Return true if THREAD is known to be stopped now.  */
 305   int (*thread_stopped) (struct thread_info *thread);
 306
 307   /* Read Thread Information Block address.  */
 308   int (*get_tib_address) (ptid_t ptid, CORE_ADDR *address);
 309
 310   /* Pause all threads.  If FREEZE, arrange for any resume attempt to
 311      be ignored until an unpause_all call unfreezes threads again.
 312      There can be nested calls to pause_all, so a freeze counter
 313      should be maintained.  */
 314   void (*pause_all) (int freeze);
 315
 316   /* Unpause all threads.  Threads that hadn't been resumed by the
 317      client should be left stopped.  Basically a pause/unpause call
 318      pair should not end up resuming threads that were stopped before
 319      the pause call.  */
 320   void (*unpause_all) (int unfreeze);
 321
 322   /* Stabilize all threads.  That is, force them out of jump pads.  */
 323   void (*stabilize_threads) (void);
 324
 325   /* Install a fast tracepoint jump pad.  TPOINT is the address of the
 326      tracepoint internal object as used by the IPA agent.  TPADDR is
 327      the address of tracepoint.  COLLECTOR is address of the function
 328      the jump pad redirects to.  LOCKADDR is the address of the jump
 329      pad lock object.  ORIG_SIZE is the size in bytes of the
 330      instruction at TPADDR.  JUMP_ENTRY points to the address of the
 331      jump pad entry, and on return holds the address past the end of
 332      the created jump pad.  If a trampoline is created by the function,
 333      then TRAMPOLINE and TRAMPOLINE_SIZE return the address and size of
 334      the trampoline, else they remain unchanged.  JJUMP_PAD_INSN is a
 335      buffer containing a copy of the instruction at TPADDR.
 336      ADJUST_INSN_ADDR and ADJUST_INSN_ADDR_END are output parameters that
 337      return the address range where the instruction at TPADDR was relocated
 338      to.  If an error occurs, the ERR may be used to pass on an error
 339      message.  */
 340   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 341                                            CORE_ADDR collector,
 342                                            CORE_ADDR lockaddr,
 343                                            ULONGEST orig_size,
 344                                            CORE_ADDR *jump_entry,
 345                                            CORE_ADDR *trampoline,
 346                                            ULONGEST *trampoline_size,
 347                                            unsigned char *jjump_pad_insn,
 348                                            ULONGEST *jjump_pad_insn_size,
 349                                            CORE_ADDR *adjusted_insn_addr,
 350                                            CORE_ADDR *adjusted_insn_addr_end,
 351                                            char *err);
 352
 353   /* Return the bytecode operations vector for the current inferior.
 354      Returns NULL if bytecode compilation is not supported.  */
 355   struct emit_ops *(*emit_ops) (void);
 356
 357   /* Returns true if the target supports disabling randomization.  */
 358   int (*supports_disable_randomization) (void);
 359
 360   /* Return the minimum length of an instruction that can be safely overwritten
 361      for use as a fast tracepoint.  */
 362   int (*get_min_fast_tracepoint_insn_len) (void);
 363
 364   /* Read solib info on SVR4 platforms.  */
 365   int (*qxfer_libraries_svr4) (const char *annex, unsigned char *readbuf,
 366                                unsigned const char *writebuf,
 367                                CORE_ADDR offset, int len);
 368
 369   /* Return true if target supports debugging agent.  */
 370   int (*supports_agent) (void);
 371
 372   /* Check whether the target supports branch tracing.  */
 373   int (*supports_btrace) (struct target_ops *, enum btrace_format);
 374
 375   /* Enable branch tracing for PTID based on CONF and allocate a branch trace
 376      target information struct for reading and for disabling branch trace.  */
 377   struct btrace_target_info *(*enable_btrace)
 378     (ptid_t ptid, const struct btrace_config *conf);
 379
 380   /* Disable branch tracing.
 381      Returns zero on success, non-zero otherwise.  */
 382   int (*disable_btrace) (struct btrace_target_info *tinfo);
 383
 384   /* Read branch trace data into buffer.  We use an int to specify the type
 385      to break a cyclic dependency.
 386      Return 0 on success; print an error message into BUFFER and return -1,
 387      otherwise.  */
 388   int (*read_btrace) (struct btrace_target_info *, struct buffer *, int type);
 389
 390   /* Read the branch trace configuration into BUFFER.
 391      Return 0 on success; print an error message into BUFFER and return -1
 392      otherwise.  */
 393   int (*read_btrace_conf) (const struct btrace_target_info *, struct buffer *);
 394
 395   /* Return true if target supports range stepping.  */
 396   int (*supports_range_stepping) (void);
 397
 398   /* Return the full absolute name of the executable file that was
 399      run to create the process PID.  If the executable file cannot
 400      be determined, NULL is returned.  Otherwise, a pointer to a
 401      character string containing the pathname is returned.  This
 402      string should be copied into a buffer by the client if the string
 403      will not be immediately used, or if it must persist.  */
 404   char *(*pid_to_exec_file) (int pid);
 405 };
 406
 407 extern struct target_ops *the_target;
 408
 409 void set_target_ops (struct target_ops *);
 410
 411 #define create_inferior(program, args) \
 412   (*the_target->create_inferior) (program, args)
 413
 414 #define myattach(pid) \
 415   (*the_target->attach) (pid)
 416
 417 int kill_inferior (int);
 418
 419 #define detach_inferior(pid) \
 420   (*the_target->detach) (pid)
 421
 422 #define mourn_inferior(PROC) \
 423   (*the_target->mourn) (PROC)
 424
 425 #define mythread_alive(pid) \
 426   (*the_target->thread_alive) (pid)
 427
 428 #define fetch_inferior_registers(regcache, regno)       \
 429   (*the_target->fetch_registers) (regcache, regno)
 430
 431 #define store_inferior_registers(regcache, regno) \
 432   (*the_target->store_registers) (regcache, regno)
 433
 434 #define join_inferior(pid) \
 435   (*the_target->join) (pid)
 436
 437 #define target_supports_non_stop() \
 438   (the_target->supports_non_stop ? (*the_target->supports_non_stop ) () : 0)
 439
 440 #define target_async(enable) \
 441   (the_target->async ? (*the_target->async) (enable) : 0)
 442
 443 #define target_supports_multi_process() \
 444   (the_target->supports_multi_process ? \
 445    (*the_target->supports_multi_process) () : 0)
 446
 447 #define target_process_qsupported(query)                \
 448   do                                                    \
 449     {                                                   \
 450       if (the_target->process_qsupported)               \
 451         the_target->process_qsupported (query);         \
 452     } while (0)
 453
 454 #define target_supports_tracepoints()                   \
 455   (the_target->supports_tracepoints                     \
 456    ? (*the_target->supports_tracepoints) () : 0)
 457
 458 #define target_supports_fast_tracepoints()              \
 459   (the_target->install_fast_tracepoint_jump_pad != NULL)
 460
 461 #define target_get_min_fast_tracepoint_insn_len()       \
 462   (the_target->get_min_fast_tracepoint_insn_len         \
 463    ? (*the_target->get_min_fast_tracepoint_insn_len) () : 0)
 464
 465 #define thread_stopped(thread) \
 466   (*the_target->thread_stopped) (thread)
 467
 468 #define pause_all(freeze)                       \
 469   do                                            \
 470     {                                           \
 471       if (the_target->pause_all)                \
 472         (*the_target->pause_all) (freeze);      \
 473     } while (0)
 474
 475 #define unpause_all(unfreeze)                   \
 476   do                                            \
 477     {                                           \
 478       if (the_target->unpause_all)              \
 479         (*the_target->unpause_all) (unfreeze);  \
 480     } while (0)
 481
 482 #define stabilize_threads()                     \
 483   do                                            \
 484     {                                           \
 485       if (the_target->stabilize_threads)        \
 486         (*the_target->stabilize_threads) ();    \
 487     } while (0)
 488
 489 #define install_fast_tracepoint_jump_pad(tpoint, tpaddr,                \
 490                                          collector, lockaddr,           \
 491                                          orig_size,                     \
 492                                          jump_entry,                    \
 493                                          trampoline, trampoline_size,   \
 494                                          jjump_pad_insn,                \
 495                                          jjump_pad_insn_size,           \
 496                                          adjusted_insn_addr,            \
 497                                          adjusted_insn_addr_end,        \
 498                                          err)                           \
 499   (*the_target->install_fast_tracepoint_jump_pad) (tpoint, tpaddr,      \
 500                                                    collector,lockaddr,  \
 501                                                    orig_size, jump_entry, \
 502                                                    trampoline,          \
 503                                                    trampoline_size,     \
 504                                                    jjump_pad_insn,      \
 505                                                    jjump_pad_insn_size, \
 506                                                    adjusted_insn_addr,  \
 507                                                    adjusted_insn_addr_end, \
 508                                                    err)
 509
 510 #define target_emit_ops() \
 511   (the_target->emit_ops ? (*the_target->emit_ops) () : NULL)
 512
 513 #define target_supports_disable_randomization() \
 514   (the_target->supports_disable_randomization ? \
 515    (*the_target->supports_disable_randomization) () : 0)
 516
 517 #define target_supports_agent() \
 518   (the_target->supports_agent ? \
 519    (*the_target->supports_agent) () : 0)
 520
 521 #define target_supports_btrace(format)                  \
 522   (the_target->supports_btrace                          \
 523    ? (*the_target->supports_btrace) (the_target, format) : 0)
 524
 525 #define target_enable_btrace(ptid, conf) \
 526   (*the_target->enable_btrace) (ptid, conf)
 527
 528 #define target_disable_btrace(tinfo) \
 529   (*the_target->disable_btrace) (tinfo)
 530
 531 #define target_read_btrace(tinfo, buffer, type) \
 532   (*the_target->read_btrace) (tinfo, buffer, type)
 533
 534 #define target_read_btrace_conf(tinfo, buffer)  \
 535   (*the_target->read_btrace_conf) (tinfo, buffer)
 536
 537 #define target_supports_range_stepping() \
 538   (the_target->supports_range_stepping ? \
 539    (*the_target->supports_range_stepping) () : 0)
 540
 541 #define target_supports_stopped_by_sw_breakpoint() \
 542   (the_target->supports_stopped_by_sw_breakpoint ? \
 543    (*the_target->supports_stopped_by_sw_breakpoint) () : 0)
 544
 545 #define target_stopped_by_sw_breakpoint() \
 546   (the_target->stopped_by_sw_breakpoint ? \
 547    (*the_target->stopped_by_sw_breakpoint) () : 0)
 548
 549 #define target_supports_stopped_by_hw_breakpoint() \
 550   (the_target->supports_stopped_by_hw_breakpoint ? \
 551    (*the_target->supports_stopped_by_hw_breakpoint) () : 0)
 552
 553 #define target_stopped_by_hw_breakpoint() \
 554   (the_target->stopped_by_hw_breakpoint ? \
 555    (*the_target->stopped_by_hw_breakpoint) () : 0)
 556
 557 /* Start non-stop mode, returns 0 on success, -1 on failure.   */
 558
 559 int start_non_stop (int nonstop);
 560
 561 ptid_t mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options,
 562                int connected_wait);
 563
 564 #define prepare_to_access_memory()              \
 565   (the_target->prepare_to_access_memory         \
 566    ? (*the_target->prepare_to_access_memory) () \
 567    : 0)
 568
 569 #define done_accessing_memory()                         \
 570   do                                                    \
 571     {                                                   \
 572       if (the_target->done_accessing_memory)            \
 573         (*the_target->done_accessing_memory) ();        \
 574     } while (0)
 575
 576 #define target_core_of_thread(ptid)             \
 577   (the_target->core_of_thread ? (*the_target->core_of_thread) (ptid) \
 578    : -1)
 579
 580 int read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 581
 582 int write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
 583                            int len);
 584
 585 void set_desired_thread (int id);
 586
 587 const char *target_pid_to_str (ptid_t);
 588
 589 #endif /* TARGET_H */