gdb/gdbserver/target.h

   1 /* Target operations for the remote server for GDB.
   2    Copyright (C) 2002-2013 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/resume.h"
  25 #include "target/wait.h"
  26 #include "target/waitstatus.h"
  27
  28 struct emit_ops;
  29 struct btrace_target_info;
  30 struct buffer;
  31
  32 /* This structure describes how to resume a particular thread (or all
  33    threads) based on the client's request.  If thread is -1, then this
  34    entry applies to all threads.  These are passed around as an
  35    array.  */
  36
  37 struct thread_resume
  38 {
  39   ptid_t thread;
  40
  41   /* How to "resume".  */
  42   enum resume_kind kind;
  43
  44   /* If non-zero, send this signal when we resume, or to stop the
  45      thread.  If stopping a thread, and this is 0, the target should
  46      stop the thread however it best decides to (e.g., SIGSTOP on
  47      linux; SuspendThread on win32).  This is a host signal value (not
  48      enum gdb_signal).  */
  49   int sig;
  50
  51   /* Range to single step within.  Valid only iff KIND is resume_step.
  52
  53      Single-step once, and then continuing stepping as long as the
  54      thread stops in this range.  (If the range is empty
  55      [STEP_RANGE_START == STEP_RANGE_END], then this is a single-step
  56      request.)  */
  57   CORE_ADDR step_range_start;   /* Inclusive */
  58   CORE_ADDR step_range_end;     /* Exclusive */
  59 };
  60
  61 struct target_ops
  62 {
  63   /* Start a new process.
  64
  65      PROGRAM is a path to the program to execute.
  66      ARGS is a standard NULL-terminated array of arguments,
  67      to be passed to the inferior as ``argv''.
  68
  69      Returns the new PID on success, -1 on failure.  Registers the new
  70      process with the process list.  */
  71
  72   int (*create_inferior) (char *program, char **args);
  73
  74   /* Attach to a running process.
  75
  76      PID is the process ID to attach to, specified by the user
  77      or a higher layer.
  78
  79      Returns -1 if attaching is unsupported, 0 on success, and calls
  80      error() otherwise.  */
  81
  82   int (*attach) (unsigned long pid);
  83
  84   /* Kill inferior PID.  Return -1 on failure, and 0 on success.  */
  85
  86   int (*kill) (int pid);
  87
  88   /* Detach from inferior PID. Return -1 on failure, and 0 on
  89      success.  */
  90
  91   int (*detach) (int pid);
  92
  93   /* The inferior process has died.  Do what is right.  */
  94
  95   void (*mourn) (struct process_info *proc);
  96
  97   /* Wait for inferior PID to exit.  */
  98   void (*join) (int pid);
  99
 100   /* Return 1 iff the thread with process ID PID is alive.  */
 101
 102   int (*thread_alive) (ptid_t pid);
 103
 104   /* Resume the inferior process.  */
 105
 106   void (*resume) (struct thread_resume *resume_info, size_t n);
 107
 108   /* Wait for the inferior process or thread to change state.  Store
 109      status through argument pointer STATUS.
 110
 111      PTID = -1 to wait for any pid to do something, PTID(pid,0,0) to
 112      wait for any thread of process pid to do something.  Return ptid
 113      of child, or -1 in case of error; store status through argument
 114      pointer STATUS.  OPTIONS is a bit set of options defined as
 115      TARGET_W* above.  If options contains TARGET_WNOHANG and there's
 116      no child stop to report, return is
 117      null_ptid/TARGET_WAITKIND_IGNORE.  */
 118
 119   ptid_t (*wait) (ptid_t ptid, struct target_waitstatus *status, int options);
 120
 121   /* Fetch registers from the inferior process.
 122
 123      If REGNO is -1, fetch all registers; otherwise, fetch at least REGNO.  */
 124
 125   void (*fetch_registers) (struct regcache *regcache, int regno);
 126
 127   /* Store registers to the inferior process.
 128
 129      If REGNO is -1, store all registers; otherwise, store at least REGNO.  */
 130
 131   void (*store_registers) (struct regcache *regcache, int regno);
 132
 133   /* Prepare to read or write memory from the inferior process.
 134      Targets use this to do what is necessary to get the state of the
 135      inferior such that it is possible to access memory.
 136
 137      This should generally only be called from client facing routines,
 138      such as gdb_read_memory/gdb_write_memory, or the insert_point
 139      callbacks.
 140
 141      Like `read_memory' and `write_memory' below, returns 0 on success
 142      and errno on failure.  */
 143
 144   int (*prepare_to_access_memory) (void);
 145
 146   /* Undo the effects of prepare_to_access_memory.  */
 147
 148   void (*done_accessing_memory) (void);
 149
 150   /* Read memory from the inferior process.  This should generally be
 151      called through read_inferior_memory, which handles breakpoint shadowing.
 152
 153      Read LEN bytes at MEMADDR into a buffer at MYADDR.
 154
 155      Returns 0 on success and errno on failure.  */
 156
 157   int (*read_memory) (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 158
 159   /* Write memory to the inferior process.  This should generally be
 160      called through write_inferior_memory, which handles breakpoint shadowing.
 161
 162      Write LEN bytes from the buffer at MYADDR to MEMADDR.
 163
 164      Returns 0 on success and errno on failure.  */
 165
 166   int (*write_memory) (CORE_ADDR memaddr, const unsigned char *myaddr,
 167                        int len);
 168
 169   /* Query GDB for the values of any symbols we're interested in.
 170      This function is called whenever we receive a "qSymbols::"
 171      query, which corresponds to every time more symbols (might)
 172      become available.  NULL if we aren't interested in any
 173      symbols.  */
 174
 175   void (*look_up_symbols) (void);
 176
 177   /* Send an interrupt request to the inferior process,
 178      however is appropriate.  */
 179
 180   void (*request_interrupt) (void);
 181
 182   /* Read auxiliary vector data from the inferior process.
 183
 184      Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 185
 186   int (*read_auxv) (CORE_ADDR offset, unsigned char *myaddr,
 187                     unsigned int len);
 188
 189   /* Insert and remove a break or watchpoint.
 190      Returns 0 on success, -1 on failure and 1 on unsupported.
 191      The type is coded as follows:
 192        '0' - software-breakpoint
 193        '1' - hardware-breakpoint
 194        '2' - write watchpoint
 195        '3' - read watchpoint
 196        '4' - access watchpoint  */
 197
 198   int (*insert_point) (char type, CORE_ADDR addr, int len);
 199   int (*remove_point) (char type, CORE_ADDR addr, int len);
 200
 201   /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise.  */
 202
 203   int (*stopped_by_watchpoint) (void);
 204
 205   /* Returns the address associated with the watchpoint that hit, if any;
 206      returns 0 otherwise.  */
 207
 208   CORE_ADDR (*stopped_data_address) (void);
 209
 210   /* Reports the text, data offsets of the executable.  This is
 211      needed for uclinux where the executable is relocated during load
 212      time.  */
 213
 214   int (*read_offsets) (CORE_ADDR *text, CORE_ADDR *data);
 215
 216   /* Fetch the address associated with a specific thread local storage
 217      area, determined by the specified THREAD, OFFSET, and LOAD_MODULE.
 218      Stores it in *ADDRESS and returns zero on success; otherwise returns
 219      an error code.  A return value of -1 means this system does not
 220      support the operation.  */
 221
 222   int (*get_tls_address) (struct thread_info *thread, CORE_ADDR offset,
 223                           CORE_ADDR load_module, CORE_ADDR *address);
 224
 225    /* Read/Write from/to spufs using qXfer packets.  */
 226   int (*qxfer_spu) (const char *annex, unsigned char *readbuf,
 227                     unsigned const char *writebuf, CORE_ADDR offset, int len);
 228
 229   /* Fill BUF with an hostio error packet representing the last hostio
 230      error.  */
 231   void (*hostio_last_error) (char *buf);
 232
 233   /* Read/Write OS data using qXfer packets.  */
 234   int (*qxfer_osdata) (const char *annex, unsigned char *readbuf,
 235                        unsigned const char *writebuf, CORE_ADDR offset,
 236                        int len);
 237
 238   /* Read/Write extra signal info.  */
 239   int (*qxfer_siginfo) (const char *annex, unsigned char *readbuf,
 240                         unsigned const char *writebuf,
 241                         CORE_ADDR offset, int len);
 242
 243   int (*supports_non_stop) (void);
 244
 245   /* Enables async target events.  Returns the previous enable
 246      state.  */
 247   int (*async) (int enable);
 248
 249   /* Switch to non-stop (1) or all-stop (0) mode.  Return 0 on
 250      success, -1 otherwise.  */
 251   int (*start_non_stop) (int);
 252
 253   /* Returns true if the target supports multi-process debugging.  */
 254   int (*supports_multi_process) (void);
 255
 256   /* If not NULL, target-specific routine to process monitor command.
 257      Returns 1 if handled, or 0 to perform default processing.  */
 258   int (*handle_monitor_command) (char *);
 259
 260   /* Returns the core given a thread, or -1 if not known.  */
 261   int (*core_of_thread) (ptid_t);
 262
 263   /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 264   int (*read_loadmap) (const char *annex, CORE_ADDR offset,
 265                        unsigned char *myaddr, unsigned int len);
 266
 267   /* Target specific qSupported support.  */
 268   void (*process_qsupported) (const char *);
 269
 270   /* Return 1 if the target supports tracepoints, 0 (or leave the
 271      callback NULL) otherwise.  */
 272   int (*supports_tracepoints) (void);
 273
 274   /* Read PC from REGCACHE.  */
 275   CORE_ADDR (*read_pc) (struct regcache *regcache);
 276
 277   /* Write PC to REGCACHE.  */
 278   void (*write_pc) (struct regcache *regcache, CORE_ADDR pc);
 279
 280   /* Return true if THREAD is known to be stopped now.  */
 281   int (*thread_stopped) (struct thread_info *thread);
 282
 283   /* Read Thread Information Block address.  */
 284   int (*get_tib_address) (ptid_t ptid, CORE_ADDR *address);
 285
 286   /* Pause all threads.  If FREEZE, arrange for any resume attempt to
 287      be ignored until an unpause_all call unfreezes threads again.
 288      There can be nested calls to pause_all, so a freeze counter
 289      should be maintained.  */
 290   void (*pause_all) (int freeze);
 291
 292   /* Unpause all threads.  Threads that hadn't been resumed by the
 293      client should be left stopped.  Basically a pause/unpause call
 294      pair should not end up resuming threads that were stopped before
 295      the pause call.  */
 296   void (*unpause_all) (int unfreeze);
 297
 298   /* Cancel all pending breakpoints hits in all threads.  */
 299   void (*cancel_breakpoints) (void);
 300
 301   /* Stabilize all threads.  That is, force them out of jump pads.  */
 302   void (*stabilize_threads) (void);
 303
 304   /* Install a fast tracepoint jump pad.  TPOINT is the address of the
 305      tracepoint internal object as used by the IPA agent.  TPADDR is
 306      the address of tracepoint.  COLLECTOR is address of the function
 307      the jump pad redirects to.  LOCKADDR is the address of the jump
 308      pad lock object.  ORIG_SIZE is the size in bytes of the
 309      instruction at TPADDR.  JUMP_ENTRY points to the address of the
 310      jump pad entry, and on return holds the address past the end of
 311      the created jump pad.  If a trampoline is created by the function,
 312      then TRAMPOLINE and TRAMPOLINE_SIZE return the address and size of
 313      the trampoline, else they remain unchanged.  JJUMP_PAD_INSN is a
 314      buffer containing a copy of the instruction at TPADDR.
 315      ADJUST_INSN_ADDR and ADJUST_INSN_ADDR_END are output parameters that
 316      return the address range where the instruction at TPADDR was relocated
 317      to.  If an error occurs, the ERR may be used to pass on an error
 318      message.  */
 319   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 320                                            CORE_ADDR collector,
 321                                            CORE_ADDR lockaddr,
 322                                            ULONGEST orig_size,
 323                                            CORE_ADDR *jump_entry,
 324                                            CORE_ADDR *trampoline,
 325                                            ULONGEST *trampoline_size,
 326                                            unsigned char *jjump_pad_insn,
 327                                            ULONGEST *jjump_pad_insn_size,
 328                                            CORE_ADDR *adjusted_insn_addr,
 329                                            CORE_ADDR *adjusted_insn_addr_end,
 330                                            char *err);
 331
 332   /* Return the bytecode operations vector for the current inferior.
 333      Returns NULL if bytecode compilation is not supported.  */
 334   struct emit_ops *(*emit_ops) (void);
 335
 336   /* Returns true if the target supports disabling randomization.  */
 337   int (*supports_disable_randomization) (void);
 338
 339   /* Return the minimum length of an instruction that can be safely overwritten
 340      for use as a fast tracepoint.  */
 341   int (*get_min_fast_tracepoint_insn_len) (void);
 342
 343   /* Read solib info on SVR4 platforms.  */
 344   int (*qxfer_libraries_svr4) (const char *annex, unsigned char *readbuf,
 345                                unsigned const char *writebuf,
 346                                CORE_ADDR offset, int len);
 347
 348   /* Return true if target supports debugging agent.  */
 349   int (*supports_agent) (void);
 350
 351   /* Check whether the target supports branch tracing.  */
 352   int (*supports_btrace) (void);
 353
 354   /* Enable branch tracing for @ptid and allocate a branch trace target
 355      information struct for reading and for disabling branch trace.  */
 356   struct btrace_target_info *(*enable_btrace) (ptid_t ptid);
 357
 358   /* Disable branch tracing.  */
 359   int (*disable_btrace) (struct btrace_target_info *tinfo);
 360
 361   /* Read branch trace data into buffer.  We use an int to specify the type
 362      to break a cyclic dependency.  */
 363   void (*read_btrace) (struct btrace_target_info *, struct buffer *, int type);
 364
 365   /* Return true if target supports range stepping.  */
 366   int (*supports_range_stepping) (void);
 367 };
 368
 369 extern struct target_ops *the_target;
 370
 371 void set_target_ops (struct target_ops *);
 372
 373 #define create_inferior(program, args) \
 374   (*the_target->create_inferior) (program, args)
 375
 376 #define myattach(pid) \
 377   (*the_target->attach) (pid)
 378
 379 int kill_inferior (int);
 380
 381 #define detach_inferior(pid) \
 382   (*the_target->detach) (pid)
 383
 384 #define mourn_inferior(PROC) \
 385   (*the_target->mourn) (PROC)
 386
 387 #define mythread_alive(pid) \
 388   (*the_target->thread_alive) (pid)
 389
 390 #define fetch_inferior_registers(regcache, regno)       \
 391   (*the_target->fetch_registers) (regcache, regno)
 392
 393 #define store_inferior_registers(regcache, regno) \
 394   (*the_target->store_registers) (regcache, regno)
 395
 396 #define join_inferior(pid) \
 397   (*the_target->join) (pid)
 398
 399 #define target_supports_non_stop() \
 400   (the_target->supports_non_stop ? (*the_target->supports_non_stop ) () : 0)
 401
 402 #define target_async(enable) \
 403   (the_target->async ? (*the_target->async) (enable) : 0)
 404
 405 #define target_supports_multi_process() \
 406   (the_target->supports_multi_process ? \
 407    (*the_target->supports_multi_process) () : 0)
 408
 409 #define target_process_qsupported(query)                \
 410   do                                                    \
 411     {                                                   \
 412       if (the_target->process_qsupported)               \
 413         the_target->process_qsupported (query);         \
 414     } while (0)
 415
 416 #define target_supports_tracepoints()                   \
 417   (the_target->supports_tracepoints                     \
 418    ? (*the_target->supports_tracepoints) () : 0)
 419
 420 #define target_supports_fast_tracepoints()              \
 421   (the_target->install_fast_tracepoint_jump_pad != NULL)
 422
 423 #define target_get_min_fast_tracepoint_insn_len()       \
 424   (the_target->get_min_fast_tracepoint_insn_len         \
 425    ? (*the_target->get_min_fast_tracepoint_insn_len) () : 0)
 426
 427 #define thread_stopped(thread) \
 428   (*the_target->thread_stopped) (thread)
 429
 430 #define pause_all(freeze)                       \
 431   do                                            \
 432     {                                           \
 433       if (the_target->pause_all)                \
 434         (*the_target->pause_all) (freeze);      \
 435     } while (0)
 436
 437 #define unpause_all(unfreeze)                   \
 438   do                                            \
 439     {                                           \
 440       if (the_target->unpause_all)              \
 441         (*the_target->unpause_all) (unfreeze);  \
 442     } while (0)
 443
 444 #define cancel_breakpoints()                    \
 445   do                                            \
 446     {                                           \
 447       if (the_target->cancel_breakpoints)       \
 448         (*the_target->cancel_breakpoints) ();   \
 449     } while (0)
 450
 451 #define stabilize_threads()                     \
 452   do                                            \
 453     {                                           \
 454       if (the_target->stabilize_threads)        \
 455         (*the_target->stabilize_threads) ();    \
 456     } while (0)
 457
 458 #define install_fast_tracepoint_jump_pad(tpoint, tpaddr,                \
 459                                          collector, lockaddr,           \
 460                                          orig_size,                     \
 461                                          jump_entry,                    \
 462                                          trampoline, trampoline_size,   \
 463                                          jjump_pad_insn,                \
 464                                          jjump_pad_insn_size,           \
 465                                          adjusted_insn_addr,            \
 466                                          adjusted_insn_addr_end,        \
 467                                          err)                           \
 468   (*the_target->install_fast_tracepoint_jump_pad) (tpoint, tpaddr,      \
 469                                                    collector,lockaddr,  \
 470                                                    orig_size, jump_entry, \
 471                                                    trampoline,          \
 472                                                    trampoline_size,     \
 473                                                    jjump_pad_insn,      \
 474                                                    jjump_pad_insn_size, \
 475                                                    adjusted_insn_addr,  \
 476                                                    adjusted_insn_addr_end, \
 477                                                    err)
 478
 479 #define target_emit_ops() \
 480   (the_target->emit_ops ? (*the_target->emit_ops) () : NULL)
 481
 482 #define target_supports_disable_randomization() \
 483   (the_target->supports_disable_randomization ? \
 484    (*the_target->supports_disable_randomization) () : 0)
 485
 486 #define target_supports_agent() \
 487   (the_target->supports_agent ? \
 488    (*the_target->supports_agent) () : 0)
 489
 490 #define target_supports_btrace() \
 491   (the_target->supports_btrace ? (*the_target->supports_btrace) () : 0)
 492
 493 #define target_enable_btrace(ptid) \
 494   (*the_target->enable_btrace) (ptid)
 495
 496 #define target_disable_btrace(tinfo) \
 497   (*the_target->disable_btrace) (tinfo)
 498
 499 #define target_read_btrace(tinfo, buffer, type) \
 500   (*the_target->read_btrace) (tinfo, buffer, type)
 501
 502 #define target_supports_range_stepping() \
 503   (the_target->supports_range_stepping ? \
 504    (*the_target->supports_range_stepping) () : 0)
 505
 506 /* Start non-stop mode, returns 0 on success, -1 on failure.   */
 507
 508 int start_non_stop (int nonstop);
 509
 510 ptid_t mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options,
 511                int connected_wait);
 512
 513 #define prepare_to_access_memory()              \
 514   (the_target->prepare_to_access_memory         \
 515    ? (*the_target->prepare_to_access_memory) () \
 516    : 0)
 517
 518 #define done_accessing_memory()                         \
 519   do                                                    \
 520     {                                                   \
 521       if (the_target->done_accessing_memory)            \
 522         (*the_target->done_accessing_memory) ();        \
 523     } while (0)
 524
 525 #define target_core_of_thread(ptid)             \
 526   (the_target->core_of_thread ? (*the_target->core_of_thread) (ptid) \
 527    : -1)
 528
 529 int read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 530
 531 int write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
 532                            int len);
 533
 534 void set_desired_inferior (int id);
 535
 536 const char *target_pid_to_str (ptid_t);
 537
 538 #endif /* TARGET_H */