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