gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2    Copyright 1990, 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support.  Written by John Gilmore.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #if !defined (TARGET_H)
  22 #define TARGET_H
  23
  24 /* This include file defines the interface between the main part
  25    of the debugger, and the part which is target-specific, or
  26    specific to the communications interface between us and the
  27    target.
  28
  29    A TARGET is an interface between the debugger and a particular
  30    kind of file or process.  Targets can be STACKED in STRATA,
  31    so that more than one target can potentially respond to a request.
  32    In particular, memory accesses will walk down the stack of targets
  33    until they find a target that is interested in handling that particular
  34    address.  STRATA are artificial boundaries on the stack, within
  35    which particular kinds of targets live.  Strata exist so that
  36    people don't get confused by pushing e.g. a process target and then
  37    a file target, and wondering why they can't see the current values
  38    of variables any more (the file target is handling them and they
  39    never get to the process target).  So when you push a file target,
  40    it goes into the file stratum, which is always below the process
  41    stratum.  */
  42
  43 #include "bfd.h"
  44
  45 enum strata {
  46         dummy_stratum,          /* The lowest of the low */
  47         file_stratum,           /* Executable files, etc */
  48         core_stratum,           /* Core dump files */
  49         download_stratum,       /* Downloading of remote targets */
  50         process_stratum         /* Executing processes */
  51 };
  52
  53 /* Stuff for target_wait.  */
  54
  55 /* Generally, what has the program done?  */
  56 enum target_waitkind {
  57   /* The program has exited.  The exit status is in value.integer.  */
  58   TARGET_WAITKIND_EXITED,
  59
  60   /* The program has stopped with a signal.  Which signal is in value.sig.  */
  61   TARGET_WAITKIND_STOPPED,
  62
  63   /* The program has terminated with a signal.  Which signal is in
  64      value.sig.  */
  65   TARGET_WAITKIND_SIGNALLED,
  66
  67   /* The program is letting us know that it dynamically loaded something
  68      (e.g. it called load(2) on AIX).  */
  69   TARGET_WAITKIND_LOADED,
  70
  71   /* Nothing happened, but we stopped anyway.  This perhaps should be handled
  72      within target_wait, but I'm not sure target_wait should be resuming the
  73      inferior.  */
  74   TARGET_WAITKIND_SPURIOUS
  75   };
  76
  77 /* The numbering of these signals is chosen to match traditional unix
  78    signals (insofar as various unices use the same numbers, anyway).
  79    It is also the numbering of the GDB remote protocol.  Other remote
  80    protocols, if they use a different numbering, should make sure to
  81    translate appropriately.  */
  82
  83 /* This is based strongly on Unix/POSIX signals for several reasons:
  84    (1) This set of signals represents a widely-accepted attempt to
  85    represent events of this sort in a portable fashion, (2) we want a
  86    signal to make it from wait to child_wait to the user intact, (3) many
  87    remote protocols use a similar encoding.  However, it is
  88    recognized that this set of signals has limitations (such as not
  89    distinguishing between various kinds of SIGSEGV, or not
  90    distinguishing hitting a breakpoint from finishing a single step).
  91    So in the future we may get around this either by adding additional
  92    signals for breakpoint, single-step, etc., or by adding signal
  93    codes; the latter seems more in the spirit of what BSD, System V,
  94    etc. are doing to address these issues.  */
  95
  96 /* For an explanation of what each signal means, see
  97    target_signal_to_string.  */
  98
  99 enum target_signal {
 100   /* Used some places (e.g. stop_signal) to record the concept that
 101      there is no signal.  */
 102   TARGET_SIGNAL_0 = 0,
 103   TARGET_SIGNAL_FIRST = 0,
 104   TARGET_SIGNAL_HUP = 1,
 105   TARGET_SIGNAL_INT = 2,
 106   TARGET_SIGNAL_QUIT = 3,
 107   TARGET_SIGNAL_ILL = 4,
 108   TARGET_SIGNAL_TRAP = 5,
 109   TARGET_SIGNAL_ABRT = 6,
 110   TARGET_SIGNAL_EMT = 7,
 111   TARGET_SIGNAL_FPE = 8,
 112   TARGET_SIGNAL_KILL = 9,
 113   TARGET_SIGNAL_BUS = 10,
 114   TARGET_SIGNAL_SEGV = 11,
 115   TARGET_SIGNAL_SYS = 12,
 116   TARGET_SIGNAL_PIPE = 13,
 117   TARGET_SIGNAL_ALRM = 14,
 118   TARGET_SIGNAL_TERM = 15,
 119   TARGET_SIGNAL_URG = 16,
 120   TARGET_SIGNAL_STOP = 17,
 121   TARGET_SIGNAL_TSTP = 18,
 122   TARGET_SIGNAL_CONT = 19,
 123   TARGET_SIGNAL_CHLD = 20,
 124   TARGET_SIGNAL_TTIN = 21,
 125   TARGET_SIGNAL_TTOU = 22,
 126   TARGET_SIGNAL_IO = 23,
 127   TARGET_SIGNAL_XCPU = 24,
 128   TARGET_SIGNAL_XFSZ = 25,
 129   TARGET_SIGNAL_VTALRM = 26,
 130   TARGET_SIGNAL_PROF = 27,
 131   TARGET_SIGNAL_WINCH = 28,
 132   TARGET_SIGNAL_LOST = 29,
 133   TARGET_SIGNAL_USR1 = 30,
 134   TARGET_SIGNAL_USR2 = 31,
 135   TARGET_SIGNAL_PWR = 32,
 136   /* Similar to SIGIO.  Perhaps they should have the same number.  */
 137   TARGET_SIGNAL_POLL = 33,
 138   TARGET_SIGNAL_WIND = 34,
 139   TARGET_SIGNAL_PHONE = 35,
 140   TARGET_SIGNAL_WAITING = 36,
 141   TARGET_SIGNAL_LWP = 37,
 142   TARGET_SIGNAL_DANGER = 38,
 143   TARGET_SIGNAL_GRANT = 39,
 144   TARGET_SIGNAL_RETRACT = 40,
 145   TARGET_SIGNAL_MSG = 41,
 146   TARGET_SIGNAL_SOUND = 42,
 147   TARGET_SIGNAL_SAK = 43,
 148   TARGET_SIGNAL_PRIO = 44,
 149   TARGET_SIGNAL_REALTIME_33 = 45,
 150   TARGET_SIGNAL_REALTIME_34 = 46,
 151   TARGET_SIGNAL_REALTIME_35 = 47,
 152   TARGET_SIGNAL_REALTIME_36 = 48,
 153   TARGET_SIGNAL_REALTIME_37 = 49,
 154   TARGET_SIGNAL_REALTIME_38 = 50,
 155   TARGET_SIGNAL_REALTIME_39 = 51,
 156   TARGET_SIGNAL_REALTIME_40 = 52,
 157   TARGET_SIGNAL_REALTIME_41 = 53,
 158   TARGET_SIGNAL_REALTIME_42 = 54,
 159   TARGET_SIGNAL_REALTIME_43 = 55,
 160   TARGET_SIGNAL_REALTIME_44 = 56,
 161   TARGET_SIGNAL_REALTIME_45 = 57,
 162   TARGET_SIGNAL_REALTIME_46 = 58,
 163   TARGET_SIGNAL_REALTIME_47 = 59,
 164   TARGET_SIGNAL_REALTIME_48 = 60,
 165   TARGET_SIGNAL_REALTIME_49 = 61,
 166   TARGET_SIGNAL_REALTIME_50 = 62,
 167   TARGET_SIGNAL_REALTIME_51 = 63,
 168   TARGET_SIGNAL_REALTIME_52 = 64,
 169   TARGET_SIGNAL_REALTIME_53 = 65,
 170   TARGET_SIGNAL_REALTIME_54 = 66,
 171   TARGET_SIGNAL_REALTIME_55 = 67,
 172   TARGET_SIGNAL_REALTIME_56 = 68,
 173   TARGET_SIGNAL_REALTIME_57 = 69,
 174   TARGET_SIGNAL_REALTIME_58 = 70,
 175   TARGET_SIGNAL_REALTIME_59 = 71,
 176   TARGET_SIGNAL_REALTIME_60 = 72,
 177   TARGET_SIGNAL_REALTIME_61 = 73,
 178   TARGET_SIGNAL_REALTIME_62 = 74,
 179   TARGET_SIGNAL_REALTIME_63 = 75,
 180
 181   /* Some signal we don't know about.  */
 182   TARGET_SIGNAL_UNKNOWN,
 183
 184   /* Use whatever signal we use when one is not specifically specified
 185      (for passing to proceed and so on).  */
 186   TARGET_SIGNAL_DEFAULT,
 187
 188   /* Last and unused enum value, for sizing arrays, etc.  */
 189   TARGET_SIGNAL_LAST
 190 };
 191
 192 struct target_waitstatus {
 193   enum target_waitkind kind;
 194
 195   /* Exit status or signal number.  */
 196   union {
 197     int integer;
 198     enum target_signal sig;
 199   } value;
 200 };
 201
 202 /* Return the string for a signal.  */
 203 extern char *target_signal_to_string PARAMS ((enum target_signal));
 204
 205 /* Return the name (SIGHUP, etc.) for a signal.  */
 206 extern char *target_signal_to_name PARAMS ((enum target_signal));
 207
 208 /* Given a name (SIGHUP, etc.), return its signal.  */
 209 enum target_signal target_signal_from_name PARAMS ((char *));
 210 \f
 211 /* If certain kinds of activity happen, target_wait should perform
 212    callbacks.  */
 213 /* Right now we just call (*TARGET_ACTIVITY_FUNCTION) if I/O is possible
 214    on TARGET_ACTIVITY_FD.   */
 215 extern int target_activity_fd;
 216 /* Returns zero to leave the inferior alone, one to interrupt it.  */
 217 extern int (*target_activity_function) PARAMS ((void));
 218 \f
 219 struct target_ops
 220 {
 221   char         *to_shortname;   /* Name this target type */
 222   char         *to_longname;    /* Name for printing */
 223   char         *to_doc;         /* Documentation.  Does not include trailing
 224                                    newline, and starts with a one-line descrip-
 225                                    tion (probably similar to to_longname). */
 226   void        (*to_open) PARAMS ((char *, int));
 227   void        (*to_close) PARAMS ((int));
 228   void        (*to_attach) PARAMS ((char *, int));
 229   void        (*to_detach) PARAMS ((char *, int));
 230   void        (*to_resume) PARAMS ((int, int, enum target_signal));
 231   int         (*to_wait) PARAMS ((int, struct target_waitstatus *));
 232   void        (*to_fetch_registers) PARAMS ((int));
 233   void        (*to_store_registers) PARAMS ((int));
 234   void        (*to_prepare_to_store) PARAMS ((void));
 235
 236   /* Transfer LEN bytes of memory between GDB address MYADDR and
 237      target address MEMADDR.  If WRITE, transfer them to the target, else
 238      transfer them from the target.  TARGET is the target from which we
 239      get this function.
 240
 241      Return value, N, is one of the following:
 242
 243      0 means that we can't handle this.  If errno has been set, it is the
 244      error which prevented us from doing it (FIXME: What about bfd_error?).
 245
 246      positive (call it N) means that we have transferred N bytes
 247      starting at MEMADDR.  We might be able to handle more bytes
 248      beyond this length, but no promises.
 249
 250      negative (call its absolute value N) means that we cannot
 251      transfer right at MEMADDR, but we could transfer at least
 252      something at MEMADDR + N.  */
 253
 254   int         (*to_xfer_memory) PARAMS ((CORE_ADDR memaddr, char *myaddr,
 255                                          int len, int write,
 256                                          struct target_ops * target));
 257
 258 #if 0
 259   /* Enable this after 4.12.  */
 260
 261   /* Search target memory.  Start at STARTADDR and take LEN bytes of
 262      target memory, and them with MASK, and compare to DATA.  If they
 263      match, set *ADDR_FOUND to the address we found it at, store the data
 264      we found at LEN bytes starting at DATA_FOUND, and return.  If
 265      not, add INCREMENT to the search address and keep trying until
 266      the search address is outside of the range [LORANGE,HIRANGE).
 267
 268      If we don't find anything, set *ADDR_FOUND to (CORE_ADDR)0 and return.  */
 269   void (*to_search) PARAMS ((int len, char *data, char *mask,
 270                              CORE_ADDR startaddr, int increment,
 271                              CORE_ADDR lorange, CORE_ADDR hirange,
 272                              CORE_ADDR *addr_found, char *data_found));
 273
 274 #define target_search(len, data, mask, startaddr, increment, lorange, hirange, addr_found, data_found)  \
 275   (*current_target.to_search) (len, data, mask, startaddr, increment, \
 276                                 lorange, hirange, addr_found, data_found)
 277 #endif /* 0 */
 278
 279   void        (*to_files_info) PARAMS ((struct target_ops *));
 280   int         (*to_insert_breakpoint) PARAMS ((CORE_ADDR, char *));
 281   int         (*to_remove_breakpoint) PARAMS ((CORE_ADDR, char *));
 282   void        (*to_terminal_init) PARAMS ((void));
 283   void        (*to_terminal_inferior) PARAMS ((void));
 284   void        (*to_terminal_ours_for_output) PARAMS ((void));
 285   void        (*to_terminal_ours) PARAMS ((void));
 286   void        (*to_terminal_info) PARAMS ((char *, int));
 287   void        (*to_kill) PARAMS ((void));
 288   void        (*to_load) PARAMS ((char *, int));
 289   int         (*to_lookup_symbol) PARAMS ((char *, CORE_ADDR *));
 290   void        (*to_create_inferior) PARAMS ((char *, char *, char **));
 291   void        (*to_mourn_inferior) PARAMS ((void));
 292   int         (*to_can_run) PARAMS ((void));
 293   void        (*to_notice_signals) PARAMS ((int pid));
 294   void        (*to_stop) PARAMS ((void));
 295   enum strata   to_stratum;
 296   struct target_ops
 297                 *DONT_USE;      /* formerly to_next */
 298   int           to_has_all_memory;
 299   int           to_has_memory;
 300   int           to_has_stack;
 301   int           to_has_registers;
 302   int           to_has_execution;
 303   struct section_table
 304                *to_sections;
 305   struct section_table
 306                *to_sections_end;
 307   int           to_magic;
 308   /* Need sub-structure for target machine related rather than comm related? */
 309 };
 310
 311 /* Magic number for checking ops size.  If a struct doesn't end with this
 312    number, somebody changed the declaration but didn't change all the
 313    places that initialize one.  */
 314
 315 #define OPS_MAGIC       3840
 316
 317 /* The ops structure for our "current" target process.  This should
 318    never be NULL.  If there is no target, it points to the dummy_target.  */
 319
 320 extern struct target_ops        current_target;
 321
 322 /* An item on the target stack.  */
 323
 324 struct target_stack_item
 325 {
 326   struct target_stack_item *next;
 327   struct target_ops *target_ops;
 328 };
 329
 330 /* The target stack.  */
 331
 332 extern struct target_stack_item *target_stack;
 333
 334 /* Define easy words for doing these operations on our current target.  */
 335
 336 #define target_shortname        (current_target.to_shortname)
 337 #define target_longname         (current_target.to_longname)
 338
 339 /* The open routine takes the rest of the parameters from the command,
 340    and (if successful) pushes a new target onto the stack.
 341    Targets should supply this routine, if only to provide an error message.  */
 342 #define target_open(name, from_tty)     \
 343         (*current_target.to_open) (name, from_tty)
 344
 345 /* Does whatever cleanup is required for a target that we are no longer
 346    going to be calling.  Argument says whether we are quitting gdb and
 347    should not get hung in case of errors, or whether we want a clean
 348    termination even if it takes a while.  This routine is automatically
 349    always called just before a routine is popped off the target stack.
 350    Closing file descriptors and freeing memory are typical things it should
 351    do.  */
 352
 353 #define target_close(quitting)  \
 354         (*current_target.to_close) (quitting)
 355
 356 /* Attaches to a process on the target side.  Arguments are as passed
 357    to the `attach' command by the user.  This routine can be called
 358    when the target is not on the target-stack, if the target_can_run
 359    routine returns 1; in that case, it must push itself onto the stack.
 360    Upon exit, the target should be ready for normal operations, and
 361    should be ready to deliver the status of the process immediately
 362    (without waiting) to an upcoming target_wait call.  */
 363
 364 #define target_attach(args, from_tty)   \
 365         (*current_target.to_attach) (args, from_tty)
 366
 367 /* Takes a program previously attached to and detaches it.
 368    The program may resume execution (some targets do, some don't) and will
 369    no longer stop on signals, etc.  We better not have left any breakpoints
 370    in the program or it'll die when it hits one.  ARGS is arguments
 371    typed by the user (e.g. a signal to send the process).  FROM_TTY
 372    says whether to be verbose or not.  */
 373
 374 extern void
 375 target_detach PARAMS ((char *, int));
 376
 377 /* Resume execution of the target process PID.  STEP says whether to
 378    single-step or to run free; SIGGNAL is the signal to be given to
 379    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 380    pass TARGET_SIGNAL_DEFAULT.  */
 381
 382 #define target_resume(pid, step, siggnal)       \
 383         (*current_target.to_resume) (pid, step, siggnal)
 384
 385 /* Wait for process pid to do something.  Pid = -1 to wait for any pid
 386    to do something.  Return pid of child, or -1 in case of error;
 387    store status through argument pointer STATUS.  Note that it is
 388    *not* OK to return_to_top_level out of target_wait without popping
 389    the debugging target from the stack; GDB isn't prepared to get back
 390    to the prompt with a debugging target but without the frame cache,
 391    stop_pc, etc., set up.  */
 392
 393 #define target_wait(pid, status)                \
 394         (*current_target.to_wait) (pid, status)
 395
 396 /* Fetch register REGNO, or all regs if regno == -1.  No result.  */
 397
 398 #define target_fetch_registers(regno)   \
 399         (*current_target.to_fetch_registers) (regno)
 400
 401 /* Store at least register REGNO, or all regs if REGNO == -1.
 402    It can store as many registers as it wants to, so target_prepare_to_store
 403    must have been previously called.  Calls error() if there are problems.  */
 404
 405 #define target_store_registers(regs)    \
 406         (*current_target.to_store_registers) (regs)
 407
 408 /* Get ready to modify the registers array.  On machines which store
 409    individual registers, this doesn't need to do anything.  On machines
 410    which store all the registers in one fell swoop, this makes sure
 411    that REGISTERS contains all the registers from the program being
 412    debugged.  */
 413
 414 #define target_prepare_to_store()       \
 415         (*current_target.to_prepare_to_store) ()
 416
 417 extern int target_read_string PARAMS ((CORE_ADDR, char **, int, int *));
 418
 419 extern int
 420 target_read_memory PARAMS ((CORE_ADDR, char *, int));
 421
 422 extern int
 423 target_read_memory_partial PARAMS ((CORE_ADDR, char *, int, int *));
 424
 425 extern int
 426 target_write_memory PARAMS ((CORE_ADDR, char *, int));
 427
 428 extern int
 429 xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
 430
 431 extern int
 432 child_xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
 433
 434 /* Transfer LEN bytes between target address MEMADDR and GDB address MYADDR.
 435    Returns 0 for success, errno code for failure (which includes partial
 436    transfers--if you want a more useful response to partial transfers, try
 437    target_read_memory_partial).  */
 438
 439 extern int target_xfer_memory PARAMS ((CORE_ADDR memaddr, char *myaddr,
 440                                        int len, int write));
 441
 442 /* From exec.c */
 443
 444 extern void
 445 print_section_info PARAMS ((struct target_ops *, bfd *));
 446
 447 /* Print a line about the current target.  */
 448
 449 #define target_files_info()     \
 450         (*current_target.to_files_info) (&current_target)
 451
 452 /* Insert a breakpoint at address ADDR in the target machine.
 453    SAVE is a pointer to memory allocated for saving the
 454    target contents.  It is guaranteed by the caller to be long enough
 455    to save "sizeof BREAKPOINT" bytes.  Result is 0 for success, or
 456    an errno value.  */
 457
 458 #define target_insert_breakpoint(addr, save)    \
 459         (*current_target.to_insert_breakpoint) (addr, save)
 460
 461 /* Remove a breakpoint at address ADDR in the target machine.
 462    SAVE is a pointer to the same save area
 463    that was previously passed to target_insert_breakpoint.
 464    Result is 0 for success, or an errno value.  */
 465
 466 #define target_remove_breakpoint(addr, save)    \
 467         (*current_target.to_remove_breakpoint) (addr, save)
 468
 469 /* Initialize the terminal settings we record for the inferior,
 470    before we actually run the inferior.  */
 471
 472 #define target_terminal_init() \
 473         (*current_target.to_terminal_init) ()
 474
 475 /* Put the inferior's terminal settings into effect.
 476    This is preparation for starting or resuming the inferior.  */
 477
 478 #define target_terminal_inferior() \
 479         (*current_target.to_terminal_inferior) ()
 480
 481 /* Put some of our terminal settings into effect,
 482    enough to get proper results from our output,
 483    but do not change into or out of RAW mode
 484    so that no input is discarded.
 485
 486    After doing this, either terminal_ours or terminal_inferior
 487    should be called to get back to a normal state of affairs.  */
 488
 489 #define target_terminal_ours_for_output() \
 490         (*current_target.to_terminal_ours_for_output) ()
 491
 492 /* Put our terminal settings into effect.
 493    First record the inferior's terminal settings
 494    so they can be restored properly later.  */
 495
 496 #define target_terminal_ours() \
 497         (*current_target.to_terminal_ours) ()
 498
 499 /* Print useful information about our terminal status, if such a thing
 500    exists.  */
 501
 502 #define target_terminal_info(arg, from_tty) \
 503         (*current_target.to_terminal_info) (arg, from_tty)
 504
 505 /* Kill the inferior process.   Make it go away.  */
 506
 507 #define target_kill() \
 508         (*current_target.to_kill) ()
 509
 510 /* Load an executable file into the target process.  This is expected to
 511    not only bring new code into the target process, but also to update
 512    GDB's symbol tables to match.  */
 513
 514 #define target_load(arg, from_tty) \
 515         (*current_target.to_load) (arg, from_tty)
 516
 517 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 518    name.  ADDRP is a CORE_ADDR * pointing to where the value of the symbol
 519    should be returned.  The result is 0 if successful, nonzero if the
 520    symbol does not exist in the target environment.  This function should
 521    not call error() if communication with the target is interrupted, since
 522    it is called from symbol reading, but should return nonzero, possibly
 523    doing a complain().  */
 524
 525 #define target_lookup_symbol(name, addrp)       \
 526   (*current_target.to_lookup_symbol) (name, addrp)
 527
 528 /* Start an inferior process and set inferior_pid to its pid.
 529    EXEC_FILE is the file to run.
 530    ALLARGS is a string containing the arguments to the program.
 531    ENV is the environment vector to pass.  Errors reported with error().
 532    On VxWorks and various standalone systems, we ignore exec_file.  */
 533
 534 #define target_create_inferior(exec_file, args, env)    \
 535         (*current_target.to_create_inferior) (exec_file, args, env)
 536
 537 /* The inferior process has died.  Do what is right.  */
 538
 539 #define target_mourn_inferior() \
 540         (*current_target.to_mourn_inferior) ()
 541
 542 /* Does target have enough data to do a run or attach command? */
 543
 544 #define target_can_run(t) \
 545         ((t)->to_can_run) ()
 546
 547 /* post process changes to signal handling in the inferior.  */
 548
 549 #define target_notice_signals(pid) \
 550         (*current_target.to_notice_signals) (pid)
 551
 552 /* Make target stop in a continuable fashion.  (For instance, under Unix, this
 553    should act like SIGSTOP).  This function is normally used by GUIs to
 554    implement a stop button.  */
 555
 556 #define target_stop() current_target.to_stop ()
 557
 558 /* Pointer to next target in the chain, e.g. a core file and an exec file.  */
 559
 560 #define target_next \
 561         (current_target.to_next)
 562
 563 /* Does the target include all of memory, or only part of it?  This
 564    determines whether we look up the target chain for other parts of
 565    memory if this target can't satisfy a request.  */
 566
 567 #define target_has_all_memory   \
 568         (current_target.to_has_all_memory)
 569
 570 /* Does the target include memory?  (Dummy targets don't.)  */
 571
 572 #define target_has_memory       \
 573         (current_target.to_has_memory)
 574
 575 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 576    we start a process.)  */
 577
 578 #define target_has_stack        \
 579         (current_target.to_has_stack)
 580
 581 /* Does the target have registers?  (Exec files don't.)  */
 582
 583 #define target_has_registers    \
 584         (current_target.to_has_registers)
 585
 586 /* Does the target have execution?  Can we make it jump (through
 587    hoops), or pop its stack a few times?  FIXME: If this is to work that
 588    way, it needs to check whether an inferior actually exists.
 589    remote-udi.c and probably other targets can be the current target
 590    when the inferior doesn't actually exist at the moment.  Right now
 591    this just tells us whether this target is *capable* of execution.  */
 592
 593 #define target_has_execution    \
 594         (current_target.to_has_execution)
 595
 596 extern void target_link PARAMS ((char *, CORE_ADDR *));
 597
 598 /* Converts a process id to a string.  Usually, the string just contains
 599    `process xyz', but on some systems it may contain
 600    `process xyz thread abc'.  */
 601
 602 #ifndef target_pid_to_str
 603 #define target_pid_to_str(PID) \
 604         normal_pid_to_str (PID)
 605 extern char *normal_pid_to_str PARAMS ((int pid));
 606 #endif
 607
 608 /* Hardware watchpoint interfaces.  */
 609
 610 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
 611    write).  */
 612
 613 #ifndef STOPPED_BY_WATCHPOINT
 614 #define STOPPED_BY_WATCHPOINT(w) 0
 615 #endif
 616
 617 /* Routines for maintenance of the target structures...
 618
 619    add_target:   Add a target to the list of all possible targets.
 620
 621    push_target:  Make this target the top of the stack of currently used
 622                  targets, within its particular stratum of the stack.  Result
 623                  is 0 if now atop the stack, nonzero if not on top (maybe
 624                  should warn user).
 625
 626    unpush_target: Remove this from the stack of currently used targets,
 627                  no matter where it is on the list.  Returns 0 if no
 628                  change, 1 if removed from stack.
 629
 630    pop_target:   Remove the top thing on the stack of current targets.  */
 631
 632 extern void
 633 add_target PARAMS ((struct target_ops *));
 634
 635 extern int
 636 push_target PARAMS ((struct target_ops *));
 637
 638 extern int
 639 unpush_target PARAMS ((struct target_ops *));
 640
 641 extern void
 642 target_preopen PARAMS ((int));
 643
 644 extern void
 645 pop_target PARAMS ((void));
 646
 647 /* Struct section_table maps address ranges to file sections.  It is
 648    mostly used with BFD files, but can be used without (e.g. for handling
 649    raw disks, or files not in formats handled by BFD).  */
 650
 651 struct section_table {
 652   CORE_ADDR addr;               /* Lowest address in section */
 653   CORE_ADDR endaddr;            /* 1+highest address in section */
 654
 655   sec_ptr the_bfd_section;
 656
 657   bfd      *bfd;                /* BFD file pointer */
 658 };
 659
 660 /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR.
 661    Returns 0 if OK, 1 on error.  */
 662
 663 extern int
 664 build_section_table PARAMS ((bfd *, struct section_table **,
 665                              struct section_table **));
 666
 667 /* From mem-break.c */
 668
 669 extern int
 670 memory_remove_breakpoint PARAMS ((CORE_ADDR, char *));
 671
 672 extern int
 673 memory_insert_breakpoint PARAMS ((CORE_ADDR, char *));
 674
 675 /* From target.c */
 676
 677 void
 678 noprocess PARAMS ((void));
 679
 680 void
 681 find_default_attach PARAMS ((char *, int));
 682
 683 void
 684 find_default_create_inferior PARAMS ((char *, char *, char **));
 685
 686 struct target_ops *
 687 find_core_target PARAMS ((void));
 688 \f
 689 /* Stuff that should be shared among the various remote targets.  */
 690
 691 /* Debugging level.  0 is off, and non-zero values mean to print some debug
 692    information (higher values, more information).  */
 693 extern int remote_debug;
 694
 695 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
 696 extern int baud_rate;
 697 \f
 698 /* Functions for helping to write a native target.  */
 699
 700 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
 701 extern void store_waitstatus PARAMS ((struct target_waitstatus *, int));
 702
 703 /* Convert between host signal numbers and enum target_signal's.  */
 704 extern enum target_signal target_signal_from_host PARAMS ((int));
 705 extern int target_signal_to_host PARAMS ((enum target_signal));
 706
 707 /* Convert from a number used in a GDB command to an enum target_signal.  */
 708 extern enum target_signal target_signal_from_command PARAMS ((int));
 709
 710 #endif  /* !defined (TARGET_H) */