gdb/gdbserver/target.h

   1 /* Target operations for the remote server for GDB.
   2    Copyright (C) 2002-2014 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 struct process_info;
  32
  33 /* This structure describes how to resume a particular thread (or all
  34    threads) based on the client's request.  If thread is -1, then this
  35    entry applies to all threads.  These are passed around as an
  36    array.  */
  37
  38 struct thread_resume
  39 {
  40   ptid_t thread;
  41
  42   /* How to "resume".  */
  43   enum resume_kind kind;
  44
  45   /* If non-zero, send this signal when we resume, or to stop the
  46      thread.  If stopping a thread, and this is 0, the target should
  47      stop the thread however it best decides to (e.g., SIGSTOP on
  48      linux; SuspendThread on win32).  This is a host signal value (not
  49      enum gdb_signal).  */
  50   int sig;
  51
  52   /* Range to single step within.  Valid only iff KIND is resume_step.
  53
  54      Single-step once, and then continuing stepping as long as the
  55      thread stops in this range.  (If the range is empty
  56      [STEP_RANGE_START == STEP_RANGE_END], then this is a single-step
  57      request.)  */
  58   CORE_ADDR step_range_start;   /* Inclusive */
  59   CORE_ADDR step_range_end;     /* Exclusive */
  60 };
  61
  62 struct target_ops
  63 {
  64   /* Start a new process.
  65
  66      PROGRAM is a path to the program to execute.
  67      ARGS is a standard NULL-terminated array of arguments,
  68      to be passed to the inferior as ``argv''.
  69
  70      Returns the new PID on success, -1 on failure.  Registers the new
  71      process with the process list.  */
  72
  73   int (*create_inferior) (char *program, char **args);
  74
  75   /* Attach to a running process.
  76
  77      PID is the process ID to attach to, specified by the user
  78      or a higher layer.
  79
  80      Returns -1 if attaching is unsupported, 0 on success, and calls
  81      error() otherwise.  */
  82
  83   int (*attach) (unsigned long pid);
  84
  85   /* Kill inferior PID.  Return -1 on failure, and 0 on success.  */
  86
  87   int (*kill) (int pid);
  88
  89   /* Detach from inferior PID. Return -1 on failure, and 0 on
  90      success.  */
  91
  92   int (*detach) (int pid);
  93
  94   /* The inferior process has died.  Do what is right.  */
  95
  96   void (*mourn) (struct process_info *proc);
  97
  98   /* Wait for inferior PID to exit.  */
  99   void (*join) (int pid);
 100
 101   /* Return 1 iff the thread with process ID PID is alive.  */
 102
 103   int (*thread_alive) (ptid_t pid);
 104
 105   /* Resume the inferior process.  */
 106
 107   void (*resume) (struct thread_resume *resume_info, size_t n);
 108
 109   /* Wait for the inferior process or thread to change state.  Store
 110      status through argument pointer STATUS.
 111
 112      PTID = -1 to wait for any pid to do something, PTID(pid,0,0) to
 113      wait for any thread of process pid to do something.  Return ptid
 114      of child, or -1 in case of error; store status through argument
 115      pointer STATUS.  OPTIONS is a bit set of options defined as
 116      TARGET_W* above.  If options contains TARGET_WNOHANG and there's
 117      no child stop to report, return is
 118      null_ptid/TARGET_WAITKIND_IGNORE.  */
 119
 120   ptid_t (*wait) (ptid_t ptid, struct target_waitstatus *status, int options);
 121
 122   /* Fetch registers from the inferior process.
 123
 124      If REGNO is -1, fetch all registers; otherwise, fetch at least REGNO.  */
 125
 126   void (*fetch_registers) (struct regcache *regcache, int regno);
 127
 128   /* Store registers to the inferior process.
 129
 130      If REGNO is -1, store all registers; otherwise, store at least REGNO.  */
 131
 132   void (*store_registers) (struct regcache *regcache, int regno);
 133
 134   /* Prepare to read or write memory from the inferior process.
 135      Targets use this to do what is necessary to get the state of the
 136      inferior such that it is possible to access memory.
 137
 138      This should generally only be called from client facing routines,
 139      such as gdb_read_memory/gdb_write_memory, or the insert_point
 140      callbacks.
 141
 142      Like `read_memory' and `write_memory' below, returns 0 on success
 143      and errno on failure.  */
 144
 145   int (*prepare_to_access_memory) (void);
 146
 147   /* Undo the effects of prepare_to_access_memory.  */
 148
 149   void (*done_accessing_memory) (void);
 150
 151   /* Read memory from the inferior process.  This should generally be
 152      called through read_inferior_memory, which handles breakpoint shadowing.
 153
 154      Read LEN bytes at MEMADDR into a buffer at MYADDR.
 155
 156      Returns 0 on success and errno on failure.  */
 157
 158   int (*read_memory) (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 159
 160   /* Write memory to the inferior process.  This should generally be
 161      called through write_inferior_memory, which handles breakpoint shadowing.
 162
 163      Write LEN bytes from the buffer at MYADDR to MEMADDR.
 164
 165      Returns 0 on success and errno on failure.  */
 166
 167   int (*write_memory) (CORE_ADDR memaddr, const unsigned char *myaddr,
 168                        int len);
 169
 170   /* Query GDB for the values of any symbols we're interested in.
 171      This function is called whenever we receive a "qSymbols::"
 172      query, which corresponds to every time more symbols (might)
 173      become available.  NULL if we aren't interested in any
 174      symbols.  */
 175
 176   void (*look_up_symbols) (void);
 177
 178   /* Send an interrupt request to the inferior process,
 179      however is appropriate.  */
 180
 181   void (*request_interrupt) (void);
 182
 183   /* Read auxiliary vector data from the inferior process.
 184
 185      Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 186
 187   int (*read_auxv) (CORE_ADDR offset, unsigned char *myaddr,
 188                     unsigned int len);
 189
 190   /* Insert and remove a break or watchpoint.
 191      Returns 0 on success, -1 on failure and 1 on unsupported.
 192      The type is coded as follows:
 193        '0' - software-breakpoint
 194        '1' - hardware-breakpoint
 195        '2' - write watchpoint
 196        '3' - read watchpoint
 197        '4' - access watchpoint  */
 198
 199   int (*insert_point) (char type, CORE_ADDR addr, int len);
 200   int (*remove_point) (char type, CORE_ADDR addr, int len);
 201
 202   /* Returns 1 if target was stopped due to a watchpoint hit, 0 otherwise.  */
 203
 204   int (*stopped_by_watchpoint) (void);
 205
 206   /* Returns the address associated with the watchpoint that hit, if any;
 207      returns 0 otherwise.  */
 208
 209   CORE_ADDR (*stopped_data_address) (void);
 210
 211   /* Reports the text, data offsets of the executable.  This is
 212      needed for uclinux where the executable is relocated during load
 213      time.  */
 214
 215   int (*read_offsets) (CORE_ADDR *text, CORE_ADDR *data);
 216
 217   /* Fetch the address associated with a specific thread local storage
 218      area, determined by the specified THREAD, OFFSET, and LOAD_MODULE.
 219      Stores it in *ADDRESS and returns zero on success; otherwise returns
 220      an error code.  A return value of -1 means this system does not
 221      support the operation.  */
 222
 223   int (*get_tls_address) (struct thread_info *thread, CORE_ADDR offset,
 224                           CORE_ADDR load_module, CORE_ADDR *address);
 225
 226    /* Read/Write from/to spufs using qXfer packets.  */
 227   int (*qxfer_spu) (const char *annex, unsigned char *readbuf,
 228                     unsigned const char *writebuf, CORE_ADDR offset, int len);
 229
 230   /* Fill BUF with an hostio error packet representing the last hostio
 231      error.  */
 232   void (*hostio_last_error) (char *buf);
 233
 234   /* Read/Write OS data using qXfer packets.  */
 235   int (*qxfer_osdata) (const char *annex, unsigned char *readbuf,
 236                        unsigned const char *writebuf, CORE_ADDR offset,
 237                        int len);
 238
 239   /* Read/Write extra signal info.  */
 240   int (*qxfer_siginfo) (const char *annex, unsigned char *readbuf,
 241                         unsigned const char *writebuf,
 242                         CORE_ADDR offset, int len);
 243
 244   int (*supports_non_stop) (void);
 245
 246   /* Enables async target events.  Returns the previous enable
 247      state.  */
 248   int (*async) (int enable);
 249
 250   /* Switch to non-stop (1) or all-stop (0) mode.  Return 0 on
 251      success, -1 otherwise.  */
 252   int (*start_non_stop) (int);
 253
 254   /* Returns true if the target supports multi-process debugging.  */
 255   int (*supports_multi_process) (void);
 256
 257   /* If not NULL, target-specific routine to process monitor command.
 258      Returns 1 if handled, or 0 to perform default processing.  */
 259   int (*handle_monitor_command) (char *);
 260
 261   /* Returns the core given a thread, or -1 if not known.  */
 262   int (*core_of_thread) (ptid_t);
 263
 264   /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 265   int (*read_loadmap) (const char *annex, CORE_ADDR offset,
 266                        unsigned char *myaddr, unsigned int len);
 267
 268   /* Target specific qSupported support.  */
 269   void (*process_qsupported) (const char *);
 270
 271   /* Return 1 if the target supports tracepoints, 0 (or leave the
 272      callback NULL) otherwise.  */
 273   int (*supports_tracepoints) (void);
 274
 275   /* Read PC from REGCACHE.  */
 276   CORE_ADDR (*read_pc) (struct regcache *regcache);
 277
 278   /* Write PC to REGCACHE.  */
 279   void (*write_pc) (struct regcache *regcache, CORE_ADDR pc);
 280
 281   /* Return true if THREAD is known to be stopped now.  */
 282   int (*thread_stopped) (struct thread_info *thread);
 283
 284   /* Read Thread Information Block address.  */
 285   int (*get_tib_address) (ptid_t ptid, CORE_ADDR *address);
 286
 287   /* Pause all threads.  If FREEZE, arrange for any resume attempt to
 288      be ignored until an unpause_all call unfreezes threads again.
 289      There can be nested calls to pause_all, so a freeze counter
 290      should be maintained.  */
 291   void (*pause_all) (int freeze);
 292
 293   /* Unpause all threads.  Threads that hadn't been resumed by the
 294      client should be left stopped.  Basically a pause/unpause call
 295      pair should not end up resuming threads that were stopped before
 296      the pause call.  */
 297   void (*unpause_all) (int unfreeze);
 298
 299   /* Cancel all pending breakpoints hits in all threads.  */
 300   void (*cancel_breakpoints) (void);
 301
 302   /* Stabilize all threads.  That is, force them out of jump pads.  */
 303   void (*stabilize_threads) (void);
 304
 305   /* Install a fast tracepoint jump pad.  TPOINT is the address of the
 306      tracepoint internal object as used by the IPA agent.  TPADDR is
 307      the address of tracepoint.  COLLECTOR is address of the function
 308      the jump pad redirects to.  LOCKADDR is the address of the jump
 309      pad lock object.  ORIG_SIZE is the size in bytes of the
 310      instruction at TPADDR.  JUMP_ENTRY points to the address of the
 311      jump pad entry, and on return holds the address past the end of
 312      the created jump pad.  If a trampoline is created by the function,
 313      then TRAMPOLINE and TRAMPOLINE_SIZE return the address and size of
 314      the trampoline, else they remain unchanged.  JJUMP_PAD_INSN is a
 315      buffer containing a copy of the instruction at TPADDR.
 316      ADJUST_INSN_ADDR and ADJUST_INSN_ADDR_END are output parameters that
 317      return the address range where the instruction at TPADDR was relocated
 318      to.  If an error occurs, the ERR may be used to pass on an error
 319      message.  */
 320   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 321                                            CORE_ADDR collector,
 322                                            CORE_ADDR lockaddr,
 323                                            ULONGEST orig_size,
 324                                            CORE_ADDR *jump_entry,
 325                                            CORE_ADDR *trampoline,
 326                                            ULONGEST *trampoline_size,
 327                                            unsigned char *jjump_pad_insn,
 328                                            ULONGEST *jjump_pad_insn_size,
 329                                            CORE_ADDR *adjusted_insn_addr,
 330                                            CORE_ADDR *adjusted_insn_addr_end,
 331                                            char *err);
 332
 333   /* Return the bytecode operations vector for the current inferior.
 334      Returns NULL if bytecode compilation is not supported.  */
 335   struct emit_ops *(*emit_ops) (void);
 336
 337   /* Returns true if the target supports disabling randomization.  */
 338   int (*supports_disable_randomization) (void);
 339
 340   /* Return the minimum length of an instruction that can be safely overwritten
 341      for use as a fast tracepoint.  */
 342   int (*get_min_fast_tracepoint_insn_len) (void);
 343
 344   /* Read solib info on SVR4 platforms.  */
 345   int (*qxfer_libraries_svr4) (const char *annex, unsigned char *readbuf,
 346                                unsigned const char *writebuf,
 347                                CORE_ADDR offset, int len);
 348
 349   /* Return true if target supports debugging agent.  */
 350   int (*supports_agent) (void);
 351
 352   /* Check whether the target supports branch tracing.  */
 353   int (*supports_btrace) (void);
 354
 355   /* Enable branch tracing for @ptid and allocate a branch trace target
 356      information struct for reading and for disabling branch trace.  */
 357   struct btrace_target_info *(*enable_btrace) (ptid_t ptid);
 358
 359   /* Disable branch tracing.
 360      Returns zero on success, non-zero otherwise.  */
 361   int (*disable_btrace) (struct btrace_target_info *tinfo);
 362
 363   /* Read branch trace data into buffer.  We use an int to specify the type
 364      to break a cyclic dependency.
 365      Return 0 on success; print an error message into BUFFER and return -1,
 366      otherwise.  */
 367   int (*read_btrace) (struct btrace_target_info *, struct buffer *, int type);
 368
 369   /* Return true if target supports range stepping.  */
 370   int (*supports_range_stepping) (void);
 371 };
 372
 373 extern struct target_ops *the_target;
 374
 375 void set_target_ops (struct target_ops *);
 376
 377 #define create_inferior(program, args) \
 378   (*the_target->create_inferior) (program, args)
 379
 380 #define myattach(pid) \
 381   (*the_target->attach) (pid)
 382
 383 int kill_inferior (int);
 384
 385 #define detach_inferior(pid) \
 386   (*the_target->detach) (pid)
 387
 388 #define mourn_inferior(PROC) \
 389   (*the_target->mourn) (PROC)
 390
 391 #define mythread_alive(pid) \
 392   (*the_target->thread_alive) (pid)
 393
 394 #define fetch_inferior_registers(regcache, regno)       \
 395   (*the_target->fetch_registers) (regcache, regno)
 396
 397 #define store_inferior_registers(regcache, regno) \
 398   (*the_target->store_registers) (regcache, regno)
 399
 400 #define join_inferior(pid) \
 401   (*the_target->join) (pid)
 402
 403 #define target_supports_non_stop() \
 404   (the_target->supports_non_stop ? (*the_target->supports_non_stop ) () : 0)
 405
 406 #define target_async(enable) \
 407   (the_target->async ? (*the_target->async) (enable) : 0)
 408
 409 #define target_supports_multi_process() \
 410   (the_target->supports_multi_process ? \
 411    (*the_target->supports_multi_process) () : 0)
 412
 413 #define target_process_qsupported(query)                \
 414   do                                                    \
 415     {                                                   \
 416       if (the_target->process_qsupported)               \
 417         the_target->process_qsupported (query);         \
 418     } while (0)
 419
 420 #define target_supports_tracepoints()                   \
 421   (the_target->supports_tracepoints                     \
 422    ? (*the_target->supports_tracepoints) () : 0)
 423
 424 #define target_supports_fast_tracepoints()              \
 425   (the_target->install_fast_tracepoint_jump_pad != NULL)
 426
 427 #define target_get_min_fast_tracepoint_insn_len()       \
 428   (the_target->get_min_fast_tracepoint_insn_len         \
 429    ? (*the_target->get_min_fast_tracepoint_insn_len) () : 0)
 430
 431 #define thread_stopped(thread) \
 432   (*the_target->thread_stopped) (thread)
 433
 434 #define pause_all(freeze)                       \
 435   do                                            \
 436     {                                           \
 437       if (the_target->pause_all)                \
 438         (*the_target->pause_all) (freeze);      \
 439     } while (0)
 440
 441 #define unpause_all(unfreeze)                   \
 442   do                                            \
 443     {                                           \
 444       if (the_target->unpause_all)              \
 445         (*the_target->unpause_all) (unfreeze);  \
 446     } while (0)
 447
 448 #define cancel_breakpoints()                    \
 449   do                                            \
 450     {                                           \
 451       if (the_target->cancel_breakpoints)       \
 452         (*the_target->cancel_breakpoints) ();   \
 453     } while (0)
 454
 455 #define stabilize_threads()                     \
 456   do                                            \
 457     {                                           \
 458       if (the_target->stabilize_threads)        \
 459         (*the_target->stabilize_threads) ();    \
 460     } while (0)
 461
 462 #define install_fast_tracepoint_jump_pad(tpoint, tpaddr,                \
 463                                          collector, lockaddr,           \
 464                                          orig_size,                     \
 465                                          jump_entry,                    \
 466                                          trampoline, trampoline_size,   \
 467                                          jjump_pad_insn,                \
 468                                          jjump_pad_insn_size,           \
 469                                          adjusted_insn_addr,            \
 470                                          adjusted_insn_addr_end,        \
 471                                          err)                           \
 472   (*the_target->install_fast_tracepoint_jump_pad) (tpoint, tpaddr,      \
 473                                                    collector,lockaddr,  \
 474                                                    orig_size, jump_entry, \
 475                                                    trampoline,          \
 476                                                    trampoline_size,     \
 477                                                    jjump_pad_insn,      \
 478                                                    jjump_pad_insn_size, \
 479                                                    adjusted_insn_addr,  \
 480                                                    adjusted_insn_addr_end, \
 481                                                    err)
 482
 483 #define target_emit_ops() \
 484   (the_target->emit_ops ? (*the_target->emit_ops) () : NULL)
 485
 486 #define target_supports_disable_randomization() \
 487   (the_target->supports_disable_randomization ? \
 488    (*the_target->supports_disable_randomization) () : 0)
 489
 490 #define target_supports_agent() \
 491   (the_target->supports_agent ? \
 492    (*the_target->supports_agent) () : 0)
 493
 494 #define target_supports_btrace() \
 495   (the_target->supports_btrace ? (*the_target->supports_btrace) () : 0)
 496
 497 #define target_enable_btrace(ptid) \
 498   (*the_target->enable_btrace) (ptid)
 499
 500 #define target_disable_btrace(tinfo) \
 501   (*the_target->disable_btrace) (tinfo)
 502
 503 #define target_read_btrace(tinfo, buffer, type) \
 504   (*the_target->read_btrace) (tinfo, buffer, type)
 505
 506 #define target_supports_range_stepping() \
 507   (the_target->supports_range_stepping ? \
 508    (*the_target->supports_range_stepping) () : 0)
 509
 510 /* Start non-stop mode, returns 0 on success, -1 on failure.   */
 511
 512 int start_non_stop (int nonstop);
 513
 514 ptid_t mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options,
 515                int connected_wait);
 516
 517 #define prepare_to_access_memory()              \
 518   (the_target->prepare_to_access_memory         \
 519    ? (*the_target->prepare_to_access_memory) () \
 520    : 0)
 521
 522 #define done_accessing_memory()                         \
 523   do                                                    \
 524     {                                                   \
 525       if (the_target->done_accessing_memory)            \
 526         (*the_target->done_accessing_memory) ();        \
 527     } while (0)
 528
 529 #define target_core_of_thread(ptid)             \
 530   (the_target->core_of_thread ? (*the_target->core_of_thread) (ptid) \
 531    : -1)
 532
 533 int read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 534
 535 int write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
 536                            int len);
 537
 538 void set_desired_inferior (int id);
 539
 540 const char *target_pid_to_str (ptid_t);
 541
 542 #endif /* TARGET_H */