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
  30 struct emit_ops;
  31 struct btrace_target_info;
  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 target was stopped due to a watchpoint hit, 0 otherwise.  */
 211
 212   int (*stopped_by_watchpoint) (void);
 213
 214   /* Returns the address associated with the watchpoint that hit, if any;
 215      returns 0 otherwise.  */
 216
 217   CORE_ADDR (*stopped_data_address) (void);
 218
 219   /* Reports the text, data offsets of the executable.  This is
 220      needed for uclinux where the executable is relocated during load
 221      time.  */
 222
 223   int (*read_offsets) (CORE_ADDR *text, CORE_ADDR *data);
 224
 225   /* Fetch the address associated with a specific thread local storage
 226      area, determined by the specified THREAD, OFFSET, and LOAD_MODULE.
 227      Stores it in *ADDRESS and returns zero on success; otherwise returns
 228      an error code.  A return value of -1 means this system does not
 229      support the operation.  */
 230
 231   int (*get_tls_address) (struct thread_info *thread, CORE_ADDR offset,
 232                           CORE_ADDR load_module, CORE_ADDR *address);
 233
 234    /* Read/Write from/to spufs using qXfer packets.  */
 235   int (*qxfer_spu) (const char *annex, unsigned char *readbuf,
 236                     unsigned const char *writebuf, CORE_ADDR offset, int len);
 237
 238   /* Fill BUF with an hostio error packet representing the last hostio
 239      error.  */
 240   void (*hostio_last_error) (char *buf);
 241
 242   /* Read/Write OS data using qXfer packets.  */
 243   int (*qxfer_osdata) (const char *annex, unsigned char *readbuf,
 244                        unsigned const char *writebuf, CORE_ADDR offset,
 245                        int len);
 246
 247   /* Read/Write extra signal info.  */
 248   int (*qxfer_siginfo) (const char *annex, unsigned char *readbuf,
 249                         unsigned const char *writebuf,
 250                         CORE_ADDR offset, int len);
 251
 252   int (*supports_non_stop) (void);
 253
 254   /* Enables async target events.  Returns the previous enable
 255      state.  */
 256   int (*async) (int enable);
 257
 258   /* Switch to non-stop (1) or all-stop (0) mode.  Return 0 on
 259      success, -1 otherwise.  */
 260   int (*start_non_stop) (int);
 261
 262   /* Returns true if the target supports multi-process debugging.  */
 263   int (*supports_multi_process) (void);
 264
 265   /* If not NULL, target-specific routine to process monitor command.
 266      Returns 1 if handled, or 0 to perform default processing.  */
 267   int (*handle_monitor_command) (char *);
 268
 269   /* Returns the core given a thread, or -1 if not known.  */
 270   int (*core_of_thread) (ptid_t);
 271
 272   /* Read loadmaps.  Read LEN bytes at OFFSET into a buffer at MYADDR.  */
 273   int (*read_loadmap) (const char *annex, CORE_ADDR offset,
 274                        unsigned char *myaddr, unsigned int len);
 275
 276   /* Target specific qSupported support.  */
 277   void (*process_qsupported) (const char *);
 278
 279   /* Return 1 if the target supports tracepoints, 0 (or leave the
 280      callback NULL) otherwise.  */
 281   int (*supports_tracepoints) (void);
 282
 283   /* Read PC from REGCACHE.  */
 284   CORE_ADDR (*read_pc) (struct regcache *regcache);
 285
 286   /* Write PC to REGCACHE.  */
 287   void (*write_pc) (struct regcache *regcache, CORE_ADDR pc);
 288
 289   /* Return true if THREAD is known to be stopped now.  */
 290   int (*thread_stopped) (struct thread_info *thread);
 291
 292   /* Read Thread Information Block address.  */
 293   int (*get_tib_address) (ptid_t ptid, CORE_ADDR *address);
 294
 295   /* Pause all threads.  If FREEZE, arrange for any resume attempt to
 296      be ignored until an unpause_all call unfreezes threads again.
 297      There can be nested calls to pause_all, so a freeze counter
 298      should be maintained.  */
 299   void (*pause_all) (int freeze);
 300
 301   /* Unpause all threads.  Threads that hadn't been resumed by the
 302      client should be left stopped.  Basically a pause/unpause call
 303      pair should not end up resuming threads that were stopped before
 304      the pause call.  */
 305   void (*unpause_all) (int unfreeze);
 306
 307   /* Cancel all pending breakpoints hits in all threads.  */
 308   void (*cancel_breakpoints) (void);
 309
 310   /* Stabilize all threads.  That is, force them out of jump pads.  */
 311   void (*stabilize_threads) (void);
 312
 313   /* Install a fast tracepoint jump pad.  TPOINT is the address of the
 314      tracepoint internal object as used by the IPA agent.  TPADDR is
 315      the address of tracepoint.  COLLECTOR is address of the function
 316      the jump pad redirects to.  LOCKADDR is the address of the jump
 317      pad lock object.  ORIG_SIZE is the size in bytes of the
 318      instruction at TPADDR.  JUMP_ENTRY points to the address of the
 319      jump pad entry, and on return holds the address past the end of
 320      the created jump pad.  If a trampoline is created by the function,
 321      then TRAMPOLINE and TRAMPOLINE_SIZE return the address and size of
 322      the trampoline, else they remain unchanged.  JJUMP_PAD_INSN is a
 323      buffer containing a copy of the instruction at TPADDR.
 324      ADJUST_INSN_ADDR and ADJUST_INSN_ADDR_END are output parameters that
 325      return the address range where the instruction at TPADDR was relocated
 326      to.  If an error occurs, the ERR may be used to pass on an error
 327      message.  */
 328   int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
 329                                            CORE_ADDR collector,
 330                                            CORE_ADDR lockaddr,
 331                                            ULONGEST orig_size,
 332                                            CORE_ADDR *jump_entry,
 333                                            CORE_ADDR *trampoline,
 334                                            ULONGEST *trampoline_size,
 335                                            unsigned char *jjump_pad_insn,
 336                                            ULONGEST *jjump_pad_insn_size,
 337                                            CORE_ADDR *adjusted_insn_addr,
 338                                            CORE_ADDR *adjusted_insn_addr_end,
 339                                            char *err);
 340
 341   /* Return the bytecode operations vector for the current inferior.
 342      Returns NULL if bytecode compilation is not supported.  */
 343   struct emit_ops *(*emit_ops) (void);
 344
 345   /* Returns true if the target supports disabling randomization.  */
 346   int (*supports_disable_randomization) (void);
 347
 348   /* Return the minimum length of an instruction that can be safely overwritten
 349      for use as a fast tracepoint.  */
 350   int (*get_min_fast_tracepoint_insn_len) (void);
 351
 352   /* Read solib info on SVR4 platforms.  */
 353   int (*qxfer_libraries_svr4) (const char *annex, unsigned char *readbuf,
 354                                unsigned const char *writebuf,
 355                                CORE_ADDR offset, int len);
 356
 357   /* Return true if target supports debugging agent.  */
 358   int (*supports_agent) (void);
 359
 360   /* Check whether the target supports branch tracing.  */
 361   int (*supports_btrace) (struct target_ops *);
 362
 363   /* Enable branch tracing for @ptid and allocate a branch trace target
 364      information struct for reading and for disabling branch trace.  */
 365   struct btrace_target_info *(*enable_btrace) (ptid_t ptid);
 366
 367   /* Disable branch tracing.
 368      Returns zero on success, non-zero otherwise.  */
 369   int (*disable_btrace) (struct btrace_target_info *tinfo);
 370
 371   /* Read branch trace data into buffer.  We use an int to specify the type
 372      to break a cyclic dependency.
 373      Return 0 on success; print an error message into BUFFER and return -1,
 374      otherwise.  */
 375   int (*read_btrace) (struct btrace_target_info *, struct buffer *, int type);
 376
 377   /* Return true if target supports range stepping.  */
 378   int (*supports_range_stepping) (void);
 379 };
 380
 381 extern struct target_ops *the_target;
 382
 383 void set_target_ops (struct target_ops *);
 384
 385 #define create_inferior(program, args) \
 386   (*the_target->create_inferior) (program, args)
 387
 388 #define myattach(pid) \
 389   (*the_target->attach) (pid)
 390
 391 int kill_inferior (int);
 392
 393 #define detach_inferior(pid) \
 394   (*the_target->detach) (pid)
 395
 396 #define mourn_inferior(PROC) \
 397   (*the_target->mourn) (PROC)
 398
 399 #define mythread_alive(pid) \
 400   (*the_target->thread_alive) (pid)
 401
 402 #define fetch_inferior_registers(regcache, regno)       \
 403   (*the_target->fetch_registers) (regcache, regno)
 404
 405 #define store_inferior_registers(regcache, regno) \
 406   (*the_target->store_registers) (regcache, regno)
 407
 408 #define join_inferior(pid) \
 409   (*the_target->join) (pid)
 410
 411 #define target_supports_non_stop() \
 412   (the_target->supports_non_stop ? (*the_target->supports_non_stop ) () : 0)
 413
 414 #define target_async(enable) \
 415   (the_target->async ? (*the_target->async) (enable) : 0)
 416
 417 #define target_supports_multi_process() \
 418   (the_target->supports_multi_process ? \
 419    (*the_target->supports_multi_process) () : 0)
 420
 421 #define target_process_qsupported(query)                \
 422   do                                                    \
 423     {                                                   \
 424       if (the_target->process_qsupported)               \
 425         the_target->process_qsupported (query);         \
 426     } while (0)
 427
 428 #define target_supports_tracepoints()                   \
 429   (the_target->supports_tracepoints                     \
 430    ? (*the_target->supports_tracepoints) () : 0)
 431
 432 #define target_supports_fast_tracepoints()              \
 433   (the_target->install_fast_tracepoint_jump_pad != NULL)
 434
 435 #define target_get_min_fast_tracepoint_insn_len()       \
 436   (the_target->get_min_fast_tracepoint_insn_len         \
 437    ? (*the_target->get_min_fast_tracepoint_insn_len) () : 0)
 438
 439 #define thread_stopped(thread) \
 440   (*the_target->thread_stopped) (thread)
 441
 442 #define pause_all(freeze)                       \
 443   do                                            \
 444     {                                           \
 445       if (the_target->pause_all)                \
 446         (*the_target->pause_all) (freeze);      \
 447     } while (0)
 448
 449 #define unpause_all(unfreeze)                   \
 450   do                                            \
 451     {                                           \
 452       if (the_target->unpause_all)              \
 453         (*the_target->unpause_all) (unfreeze);  \
 454     } while (0)
 455
 456 #define cancel_breakpoints()                    \
 457   do                                            \
 458     {                                           \
 459       if (the_target->cancel_breakpoints)       \
 460         (*the_target->cancel_breakpoints) ();   \
 461     } while (0)
 462
 463 #define stabilize_threads()                     \
 464   do                                            \
 465     {                                           \
 466       if (the_target->stabilize_threads)        \
 467         (*the_target->stabilize_threads) ();    \
 468     } while (0)
 469
 470 #define install_fast_tracepoint_jump_pad(tpoint, tpaddr,                \
 471                                          collector, lockaddr,           \
 472                                          orig_size,                     \
 473                                          jump_entry,                    \
 474                                          trampoline, trampoline_size,   \
 475                                          jjump_pad_insn,                \
 476                                          jjump_pad_insn_size,           \
 477                                          adjusted_insn_addr,            \
 478                                          adjusted_insn_addr_end,        \
 479                                          err)                           \
 480   (*the_target->install_fast_tracepoint_jump_pad) (tpoint, tpaddr,      \
 481                                                    collector,lockaddr,  \
 482                                                    orig_size, jump_entry, \
 483                                                    trampoline,          \
 484                                                    trampoline_size,     \
 485                                                    jjump_pad_insn,      \
 486                                                    jjump_pad_insn_size, \
 487                                                    adjusted_insn_addr,  \
 488                                                    adjusted_insn_addr_end, \
 489                                                    err)
 490
 491 #define target_emit_ops() \
 492   (the_target->emit_ops ? (*the_target->emit_ops) () : NULL)
 493
 494 #define target_supports_disable_randomization() \
 495   (the_target->supports_disable_randomization ? \
 496    (*the_target->supports_disable_randomization) () : 0)
 497
 498 #define target_supports_agent() \
 499   (the_target->supports_agent ? \
 500    (*the_target->supports_agent) () : 0)
 501
 502 #define target_supports_btrace()                        \
 503   (the_target->supports_btrace                          \
 504    ? (*the_target->supports_btrace) (the_target) : 0)
 505
 506 #define target_enable_btrace(ptid) \
 507   (*the_target->enable_btrace) (ptid)
 508
 509 #define target_disable_btrace(tinfo) \
 510   (*the_target->disable_btrace) (tinfo)
 511
 512 #define target_read_btrace(tinfo, buffer, type) \
 513   (*the_target->read_btrace) (tinfo, buffer, type)
 514
 515 #define target_supports_range_stepping() \
 516   (the_target->supports_range_stepping ? \
 517    (*the_target->supports_range_stepping) () : 0)
 518
 519 /* Start non-stop mode, returns 0 on success, -1 on failure.   */
 520
 521 int start_non_stop (int nonstop);
 522
 523 ptid_t mywait (ptid_t ptid, struct target_waitstatus *ourstatus, int options,
 524                int connected_wait);
 525
 526 #define prepare_to_access_memory()              \
 527   (the_target->prepare_to_access_memory         \
 528    ? (*the_target->prepare_to_access_memory) () \
 529    : 0)
 530
 531 #define done_accessing_memory()                         \
 532   do                                                    \
 533     {                                                   \
 534       if (the_target->done_accessing_memory)            \
 535         (*the_target->done_accessing_memory) ();        \
 536     } while (0)
 537
 538 #define target_core_of_thread(ptid)             \
 539   (the_target->core_of_thread ? (*the_target->core_of_thread) (ptid) \
 540    : -1)
 541
 542 int read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len);
 543
 544 int write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr,
 545                            int len);
 546
 547 void set_desired_thread (int id);
 548
 549 const char *target_pid_to_str (ptid_t);
 550
 551 #endif /* TARGET_H */