gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2    Copyright 1990-1994, 1999, 2000 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., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #if !defined (TARGET_H)
  23 #define TARGET_H
  24
  25 /* This include file defines the interface between the main part
  26    of the debugger, and the part which is target-specific, or
  27    specific to the communications interface between us and the
  28    target.
  29
  30    A TARGET is an interface between the debugger and a particular
  31    kind of file or process.  Targets can be STACKED in STRATA,
  32    so that more than one target can potentially respond to a request.
  33    In particular, memory accesses will walk down the stack of targets
  34    until they find a target that is interested in handling that particular
  35    address.  STRATA are artificial boundaries on the stack, within
  36    which particular kinds of targets live.  Strata exist so that
  37    people don't get confused by pushing e.g. a process target and then
  38    a file target, and wondering why they can't see the current values
  39    of variables any more (the file target is handling them and they
  40    never get to the process target).  So when you push a file target,
  41    it goes into the file stratum, which is always below the process
  42    stratum.  */
  43
  44 #include "bfd.h"
  45 #include "symtab.h"
  46 #include "dcache.h"
  47
  48 enum strata
  49   {
  50     dummy_stratum,              /* The lowest of the low */
  51     file_stratum,               /* Executable files, etc */
  52     core_stratum,               /* Core dump files */
  53     download_stratum,           /* Downloading of remote targets */
  54     process_stratum,            /* Executing processes */
  55     thread_stratum              /* Executing threads */
  56   };
  57
  58 enum thread_control_capabilities
  59   {
  60     tc_none = 0,                /* Default: can't control thread execution.  */
  61     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  62     tc_switch = 2               /* Can switch the running thread on demand.  */
  63   };
  64
  65 /* Stuff for target_wait.  */
  66
  67 /* Generally, what has the program done?  */
  68 enum target_waitkind
  69   {
  70     /* The program has exited.  The exit status is in value.integer.  */
  71     TARGET_WAITKIND_EXITED,
  72
  73     /* The program has stopped with a signal.  Which signal is in
  74        value.sig.  */
  75     TARGET_WAITKIND_STOPPED,
  76
  77     /* The program has terminated with a signal.  Which signal is in
  78        value.sig.  */
  79     TARGET_WAITKIND_SIGNALLED,
  80
  81     /* The program is letting us know that it dynamically loaded something
  82        (e.g. it called load(2) on AIX).  */
  83     TARGET_WAITKIND_LOADED,
  84
  85     /* The program has forked.  A "related" process' ID is in
  86        value.related_pid.  I.e., if the child forks, value.related_pid
  87        is the parent's ID.  */
  88
  89     TARGET_WAITKIND_FORKED,
  90
  91     /* The program has vforked.  A "related" process's ID is in
  92        value.related_pid.  */
  93
  94     TARGET_WAITKIND_VFORKED,
  95
  96     /* The program has exec'ed a new executable file.  The new file's
  97        pathname is pointed to by value.execd_pathname.  */
  98
  99     TARGET_WAITKIND_EXECD,
 100
 101     /* The program has entered or returned from a system call.  On
 102        HP-UX, this is used in the hardware watchpoint implementation.
 103        The syscall's unique integer ID number is in value.syscall_id */
 104
 105     TARGET_WAITKIND_SYSCALL_ENTRY,
 106     TARGET_WAITKIND_SYSCALL_RETURN,
 107
 108     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 109        within target_wait, but I'm not sure target_wait should be resuming the
 110        inferior.  */
 111     TARGET_WAITKIND_SPURIOUS,
 112
 113     /* This is used for target async and extended-async
 114        only. Remote_async_wait() returns this when there is an event
 115        on the inferior, but the rest of the world is not interested in
 116        it. The inferior has not stopped, but has just sent some output
 117        to the console, for instance. In this case, we want to go back
 118        to the event loop and wait there for another event from the
 119        inferior, rather than being stuck in the remote_async_wait()
 120        function. This way the event loop is responsive to other events,
 121        like for instance the user typing.  */
 122     TARGET_WAITKIND_IGNORE
 123   };
 124
 125 /* The numbering of these signals is chosen to match traditional unix
 126    signals (insofar as various unices use the same numbers, anyway).
 127    It is also the numbering of the GDB remote protocol.  Other remote
 128    protocols, if they use a different numbering, should make sure to
 129    translate appropriately.
 130
 131    Since these numbers have actually made it out into other software
 132    (stubs, etc.), you mustn't disturb the assigned numbering.  If you
 133    need to add new signals here, add them to the end of the explicitly
 134    numbered signals.
 135
 136    This is based strongly on Unix/POSIX signals for several reasons:
 137    (1) This set of signals represents a widely-accepted attempt to
 138    represent events of this sort in a portable fashion, (2) we want a
 139    signal to make it from wait to child_wait to the user intact, (3) many
 140    remote protocols use a similar encoding.  However, it is
 141    recognized that this set of signals has limitations (such as not
 142    distinguishing between various kinds of SIGSEGV, or not
 143    distinguishing hitting a breakpoint from finishing a single step).
 144    So in the future we may get around this either by adding additional
 145    signals for breakpoint, single-step, etc., or by adding signal
 146    codes; the latter seems more in the spirit of what BSD, System V,
 147    etc. are doing to address these issues.  */
 148
 149 /* For an explanation of what each signal means, see
 150    target_signal_to_string.  */
 151
 152 enum target_signal
 153   {
 154     /* Used some places (e.g. stop_signal) to record the concept that
 155        there is no signal.  */
 156     TARGET_SIGNAL_0 = 0,
 157     TARGET_SIGNAL_FIRST = 0,
 158     TARGET_SIGNAL_HUP = 1,
 159     TARGET_SIGNAL_INT = 2,
 160     TARGET_SIGNAL_QUIT = 3,
 161     TARGET_SIGNAL_ILL = 4,
 162     TARGET_SIGNAL_TRAP = 5,
 163     TARGET_SIGNAL_ABRT = 6,
 164     TARGET_SIGNAL_EMT = 7,
 165     TARGET_SIGNAL_FPE = 8,
 166     TARGET_SIGNAL_KILL = 9,
 167     TARGET_SIGNAL_BUS = 10,
 168     TARGET_SIGNAL_SEGV = 11,
 169     TARGET_SIGNAL_SYS = 12,
 170     TARGET_SIGNAL_PIPE = 13,
 171     TARGET_SIGNAL_ALRM = 14,
 172     TARGET_SIGNAL_TERM = 15,
 173     TARGET_SIGNAL_URG = 16,
 174     TARGET_SIGNAL_STOP = 17,
 175     TARGET_SIGNAL_TSTP = 18,
 176     TARGET_SIGNAL_CONT = 19,
 177     TARGET_SIGNAL_CHLD = 20,
 178     TARGET_SIGNAL_TTIN = 21,
 179     TARGET_SIGNAL_TTOU = 22,
 180     TARGET_SIGNAL_IO = 23,
 181     TARGET_SIGNAL_XCPU = 24,
 182     TARGET_SIGNAL_XFSZ = 25,
 183     TARGET_SIGNAL_VTALRM = 26,
 184     TARGET_SIGNAL_PROF = 27,
 185     TARGET_SIGNAL_WINCH = 28,
 186     TARGET_SIGNAL_LOST = 29,
 187     TARGET_SIGNAL_USR1 = 30,
 188     TARGET_SIGNAL_USR2 = 31,
 189     TARGET_SIGNAL_PWR = 32,
 190     /* Similar to SIGIO.  Perhaps they should have the same number.  */
 191     TARGET_SIGNAL_POLL = 33,
 192     TARGET_SIGNAL_WIND = 34,
 193     TARGET_SIGNAL_PHONE = 35,
 194     TARGET_SIGNAL_WAITING = 36,
 195     TARGET_SIGNAL_LWP = 37,
 196     TARGET_SIGNAL_DANGER = 38,
 197     TARGET_SIGNAL_GRANT = 39,
 198     TARGET_SIGNAL_RETRACT = 40,
 199     TARGET_SIGNAL_MSG = 41,
 200     TARGET_SIGNAL_SOUND = 42,
 201     TARGET_SIGNAL_SAK = 43,
 202     TARGET_SIGNAL_PRIO = 44,
 203     TARGET_SIGNAL_REALTIME_33 = 45,
 204     TARGET_SIGNAL_REALTIME_34 = 46,
 205     TARGET_SIGNAL_REALTIME_35 = 47,
 206     TARGET_SIGNAL_REALTIME_36 = 48,
 207     TARGET_SIGNAL_REALTIME_37 = 49,
 208     TARGET_SIGNAL_REALTIME_38 = 50,
 209     TARGET_SIGNAL_REALTIME_39 = 51,
 210     TARGET_SIGNAL_REALTIME_40 = 52,
 211     TARGET_SIGNAL_REALTIME_41 = 53,
 212     TARGET_SIGNAL_REALTIME_42 = 54,
 213     TARGET_SIGNAL_REALTIME_43 = 55,
 214     TARGET_SIGNAL_REALTIME_44 = 56,
 215     TARGET_SIGNAL_REALTIME_45 = 57,
 216     TARGET_SIGNAL_REALTIME_46 = 58,
 217     TARGET_SIGNAL_REALTIME_47 = 59,
 218     TARGET_SIGNAL_REALTIME_48 = 60,
 219     TARGET_SIGNAL_REALTIME_49 = 61,
 220     TARGET_SIGNAL_REALTIME_50 = 62,
 221     TARGET_SIGNAL_REALTIME_51 = 63,
 222     TARGET_SIGNAL_REALTIME_52 = 64,
 223     TARGET_SIGNAL_REALTIME_53 = 65,
 224     TARGET_SIGNAL_REALTIME_54 = 66,
 225     TARGET_SIGNAL_REALTIME_55 = 67,
 226     TARGET_SIGNAL_REALTIME_56 = 68,
 227     TARGET_SIGNAL_REALTIME_57 = 69,
 228     TARGET_SIGNAL_REALTIME_58 = 70,
 229     TARGET_SIGNAL_REALTIME_59 = 71,
 230     TARGET_SIGNAL_REALTIME_60 = 72,
 231     TARGET_SIGNAL_REALTIME_61 = 73,
 232     TARGET_SIGNAL_REALTIME_62 = 74,
 233     TARGET_SIGNAL_REALTIME_63 = 75,
 234
 235     /* Used internally by Solaris threads.  See signal(5) on Solaris.  */
 236     TARGET_SIGNAL_CANCEL = 76,
 237
 238     /* Yes, this pains me, too.  But LynxOS didn't have SIG32, and now
 239        Linux does, and we can't disturb the numbering, since it's part
 240        of the protocol.  Note that in some GDB's TARGET_SIGNAL_REALTIME_32
 241        is number 76.  */
 242     TARGET_SIGNAL_REALTIME_32,
 243
 244 #if defined(MACH) || defined(__MACH__)
 245     /* Mach exceptions */
 246     TARGET_EXC_BAD_ACCESS,
 247     TARGET_EXC_BAD_INSTRUCTION,
 248     TARGET_EXC_ARITHMETIC,
 249     TARGET_EXC_EMULATION,
 250     TARGET_EXC_SOFTWARE,
 251     TARGET_EXC_BREAKPOINT,
 252 #endif
 253     TARGET_SIGNAL_INFO,
 254
 255     /* Some signal we don't know about.  */
 256     TARGET_SIGNAL_UNKNOWN,
 257
 258     /* Use whatever signal we use when one is not specifically specified
 259        (for passing to proceed and so on).  */
 260     TARGET_SIGNAL_DEFAULT,
 261
 262     /* Last and unused enum value, for sizing arrays, etc.  */
 263     TARGET_SIGNAL_LAST
 264   };
 265
 266 struct target_waitstatus
 267   {
 268     enum target_waitkind kind;
 269
 270     /* Forked child pid, execd pathname, exit status or signal number.  */
 271     union
 272       {
 273         int integer;
 274         enum target_signal sig;
 275         int related_pid;
 276         char *execd_pathname;
 277         int syscall_id;
 278       }
 279     value;
 280   };
 281
 282 /* Possible types of events that the inferior handler will have to
 283    deal with.  */
 284 enum inferior_event_type
 285   {
 286     /* There is a request to quit the inferior, abandon it.  */
 287     INF_QUIT_REQ,
 288     /* Process a normal inferior event which will result in target_wait
 289        being called.  */
 290     INF_REG_EVENT,
 291     /* Deal with an error on the inferior.  */
 292     INF_ERROR,
 293     /* We are called because a timer went off.  */
 294     INF_TIMER,
 295     /* We are called to do stuff after the inferior stops.  */
 296     INF_EXEC_COMPLETE,
 297     /* We are called to do some stuff after the inferior stops, but we
 298        are expected to reenter the proceed() and
 299        handle_inferior_event() functions. This is used only in case of
 300        'step n' like commands.  */
 301     INF_EXEC_CONTINUE
 302   };
 303
 304 /* Return the string for a signal.  */
 305 extern char *target_signal_to_string (enum target_signal);
 306
 307 /* Return the name (SIGHUP, etc.) for a signal.  */
 308 extern char *target_signal_to_name (enum target_signal);
 309
 310 /* Given a name (SIGHUP, etc.), return its signal.  */
 311 enum target_signal target_signal_from_name (char *);
 312 \f
 313
 314 /* If certain kinds of activity happen, target_wait should perform
 315    callbacks.  */
 316 /* Right now we just call (*TARGET_ACTIVITY_FUNCTION) if I/O is possible
 317    on TARGET_ACTIVITY_FD.  */
 318 extern int target_activity_fd;
 319 /* Returns zero to leave the inferior alone, one to interrupt it.  */
 320 extern int (*target_activity_function) (void);
 321 \f
 322 struct thread_info;             /* fwd decl for parameter list below: */
 323
 324 struct target_ops
 325   {
 326     char *to_shortname;         /* Name this target type */
 327     char *to_longname;          /* Name for printing */
 328     char *to_doc;               /* Documentation.  Does not include trailing
 329                                    newline, and starts with a one-line descrip-
 330                                    tion (probably similar to to_longname).  */
 331     void (*to_open) (char *, int);
 332     void (*to_close) (int);
 333     void (*to_attach) (char *, int);
 334     void (*to_post_attach) (int);
 335     void (*to_require_attach) (char *, int);
 336     void (*to_detach) (char *, int);
 337     void (*to_require_detach) (int, char *, int);
 338     void (*to_resume) (int, int, enum target_signal);
 339     int (*to_wait) (int, struct target_waitstatus *);
 340     void (*to_post_wait) (int, int);
 341     void (*to_fetch_registers) (int);
 342     void (*to_store_registers) (int);
 343     void (*to_prepare_to_store) (void);
 344
 345     /* Transfer LEN bytes of memory between GDB address MYADDR and
 346        target address MEMADDR.  If WRITE, transfer them to the target, else
 347        transfer them from the target.  TARGET is the target from which we
 348        get this function.
 349
 350        Return value, N, is one of the following:
 351
 352        0 means that we can't handle this.  If errno has been set, it is the
 353        error which prevented us from doing it (FIXME: What about bfd_error?).
 354
 355        positive (call it N) means that we have transferred N bytes
 356        starting at MEMADDR.  We might be able to handle more bytes
 357        beyond this length, but no promises.
 358
 359        negative (call its absolute value N) means that we cannot
 360        transfer right at MEMADDR, but we could transfer at least
 361        something at MEMADDR + N.  */
 362
 363     int (*to_xfer_memory) (CORE_ADDR memaddr, char *myaddr,
 364                            int len, int write, struct target_ops * target);
 365
 366 #if 0
 367     /* Enable this after 4.12.  */
 368
 369     /* Search target memory.  Start at STARTADDR and take LEN bytes of
 370        target memory, and them with MASK, and compare to DATA.  If they
 371        match, set *ADDR_FOUND to the address we found it at, store the data
 372        we found at LEN bytes starting at DATA_FOUND, and return.  If
 373        not, add INCREMENT to the search address and keep trying until
 374        the search address is outside of the range [LORANGE,HIRANGE).
 375
 376        If we don't find anything, set *ADDR_FOUND to (CORE_ADDR)0 and
 377        return.  */
 378
 379     void (*to_search) (int len, char *data, char *mask,
 380                        CORE_ADDR startaddr, int increment,
 381                        CORE_ADDR lorange, CORE_ADDR hirange,
 382                        CORE_ADDR * addr_found, char *data_found);
 383
 384 #define target_search(len, data, mask, startaddr, increment, lorange, hirange, addr_found, data_found)  \
 385     (*current_target.to_search) (len, data, mask, startaddr, increment, \
 386                                  lorange, hirange, addr_found, data_found)
 387 #endif                          /* 0 */
 388
 389     void (*to_files_info) (struct target_ops *);
 390     int (*to_insert_breakpoint) (CORE_ADDR, char *);
 391     int (*to_remove_breakpoint) (CORE_ADDR, char *);
 392     void (*to_terminal_init) (void);
 393     void (*to_terminal_inferior) (void);
 394     void (*to_terminal_ours_for_output) (void);
 395     void (*to_terminal_ours) (void);
 396     void (*to_terminal_info) (char *, int);
 397     void (*to_kill) (void);
 398     void (*to_load) (char *, int);
 399     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 400     void (*to_create_inferior) (char *, char *, char **);
 401     void (*to_post_startup_inferior) (int);
 402     void (*to_acknowledge_created_inferior) (int);
 403     void (*to_clone_and_follow_inferior) (int, int *);
 404     void (*to_post_follow_inferior_by_clone) (void);
 405     int (*to_insert_fork_catchpoint) (int);
 406     int (*to_remove_fork_catchpoint) (int);
 407     int (*to_insert_vfork_catchpoint) (int);
 408     int (*to_remove_vfork_catchpoint) (int);
 409     int (*to_has_forked) (int, int *);
 410     int (*to_has_vforked) (int, int *);
 411     int (*to_can_follow_vfork_prior_to_exec) (void);
 412     void (*to_post_follow_vfork) (int, int, int, int);
 413     int (*to_insert_exec_catchpoint) (int);
 414     int (*to_remove_exec_catchpoint) (int);
 415     int (*to_has_execd) (int, char **);
 416     int (*to_reported_exec_events_per_exec_call) (void);
 417     int (*to_has_syscall_event) (int, enum target_waitkind *, int *);
 418     int (*to_has_exited) (int, int, int *);
 419     void (*to_mourn_inferior) (void);
 420     int (*to_can_run) (void);
 421     void (*to_notice_signals) (int pid);
 422     int (*to_thread_alive) (int pid);
 423     void (*to_find_new_threads) (void);
 424     char *(*to_pid_to_str) (int);
 425     char *(*to_extra_thread_info) (struct thread_info *);
 426     void (*to_stop) (void);
 427     int (*to_query) (int /*char */ , char *, char *, int *);
 428     void (*to_rcmd) (char *command, struct ui_file *output);
 429     struct symtab_and_line *(*to_enable_exception_callback) (enum
 430                                                              exception_event_kind,
 431                                                              int);
 432     struct exception_event_record *(*to_get_current_exception_event) (void);
 433     char *(*to_pid_to_exec_file) (int pid);
 434     char *(*to_core_file_to_sym_file) (char *);
 435     enum strata to_stratum;
 436     struct target_ops
 437      *DONT_USE;                 /* formerly to_next */
 438     int to_has_all_memory;
 439     int to_has_memory;
 440     int to_has_stack;
 441     int to_has_registers;
 442     int to_has_execution;
 443     int to_has_thread_control;  /* control thread execution */
 444     struct section_table
 445      *to_sections;
 446     struct section_table
 447      *to_sections_end;
 448     /* ASYNC target controls */
 449     int (*to_can_async_p) (void);
 450     int (*to_is_async_p) (void);
 451     void (*to_async) (void (*cb) (enum inferior_event_type, void *context),
 452                       void *context);
 453     int to_async_mask_value;
 454     int to_magic;
 455     /* Need sub-structure for target machine related rather than comm related?
 456      */
 457   };
 458
 459 /* Magic number for checking ops size.  If a struct doesn't end with this
 460    number, somebody changed the declaration but didn't change all the
 461    places that initialize one.  */
 462
 463 #define OPS_MAGIC       3840
 464
 465 /* The ops structure for our "current" target process.  This should
 466    never be NULL.  If there is no target, it points to the dummy_target.  */
 467
 468 extern struct target_ops current_target;
 469
 470 /* An item on the target stack.  */
 471
 472 struct target_stack_item
 473   {
 474     struct target_stack_item *next;
 475     struct target_ops *target_ops;
 476   };
 477
 478 /* The target stack.  */
 479
 480 extern struct target_stack_item *target_stack;
 481
 482 /* Define easy words for doing these operations on our current target.  */
 483
 484 #define target_shortname        (current_target.to_shortname)
 485 #define target_longname         (current_target.to_longname)
 486
 487 /* The open routine takes the rest of the parameters from the command,
 488    and (if successful) pushes a new target onto the stack.
 489    Targets should supply this routine, if only to provide an error message.  */
 490
 491 #define target_open(name, from_tty)                                     \
 492   do {                                                                  \
 493     dcache_invalidate (target_dcache);                                  \
 494     (*current_target.to_open) (name, from_tty);                         \
 495   } while (0)
 496
 497 /* Does whatever cleanup is required for a target that we are no longer
 498    going to be calling.  Argument says whether we are quitting gdb and
 499    should not get hung in case of errors, or whether we want a clean
 500    termination even if it takes a while.  This routine is automatically
 501    always called just before a routine is popped off the target stack.
 502    Closing file descriptors and freeing memory are typical things it should
 503    do.  */
 504
 505 #define target_close(quitting)  \
 506      (*current_target.to_close) (quitting)
 507
 508 /* Attaches to a process on the target side.  Arguments are as passed
 509    to the `attach' command by the user.  This routine can be called
 510    when the target is not on the target-stack, if the target_can_run
 511    routine returns 1; in that case, it must push itself onto the stack.
 512    Upon exit, the target should be ready for normal operations, and
 513    should be ready to deliver the status of the process immediately
 514    (without waiting) to an upcoming target_wait call.  */
 515
 516 #define target_attach(args, from_tty)   \
 517      (*current_target.to_attach) (args, from_tty)
 518
 519 /* The target_attach operation places a process under debugger control,
 520    and stops the process.
 521
 522    This operation provides a target-specific hook that allows the
 523    necessary bookkeeping to be performed after an attach completes.  */
 524 #define target_post_attach(pid) \
 525      (*current_target.to_post_attach) (pid)
 526
 527 /* Attaches to a process on the target side, if not already attached.
 528    (If already attached, takes no action.)
 529
 530    This operation can be used to follow the child process of a fork.
 531    On some targets, such child processes of an original inferior process
 532    are automatically under debugger control, and thus do not require an
 533    actual attach operation.  */
 534
 535 #define target_require_attach(args, from_tty)   \
 536      (*current_target.to_require_attach) (args, from_tty)
 537
 538 /* Takes a program previously attached to and detaches it.
 539    The program may resume execution (some targets do, some don't) and will
 540    no longer stop on signals, etc.  We better not have left any breakpoints
 541    in the program or it'll die when it hits one.  ARGS is arguments
 542    typed by the user (e.g. a signal to send the process).  FROM_TTY
 543    says whether to be verbose or not.  */
 544
 545 extern void target_detach (char *, int);
 546
 547 /* Detaches from a process on the target side, if not already dettached.
 548    (If already detached, takes no action.)
 549
 550    This operation can be used to follow the parent process of a fork.
 551    On some targets, such child processes of an original inferior process
 552    are automatically under debugger control, and thus do require an actual
 553    detach operation.
 554
 555    PID is the process id of the child to detach from.
 556    ARGS is arguments typed by the user (e.g. a signal to send the process).
 557    FROM_TTY says whether to be verbose or not.  */
 558
 559 #define target_require_detach(pid, args, from_tty)      \
 560      (*current_target.to_require_detach) (pid, args, from_tty)
 561
 562 /* Resume execution of the target process PID.  STEP says whether to
 563    single-step or to run free; SIGGNAL is the signal to be given to
 564    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 565    pass TARGET_SIGNAL_DEFAULT.  */
 566
 567 #define target_resume(pid, step, siggnal)                               \
 568   do {                                                                  \
 569     dcache_invalidate(target_dcache);                                   \
 570     (*current_target.to_resume) (pid, step, siggnal);                   \
 571   } while (0)
 572
 573 /* Wait for process pid to do something.  Pid = -1 to wait for any pid
 574    to do something.  Return pid of child, or -1 in case of error;
 575    store status through argument pointer STATUS.  Note that it is
 576    *not* OK to return_to_top_level out of target_wait without popping
 577    the debugging target from the stack; GDB isn't prepared to get back
 578    to the prompt with a debugging target but without the frame cache,
 579    stop_pc, etc., set up.  */
 580
 581 #define target_wait(pid, status)                \
 582      (*current_target.to_wait) (pid, status)
 583
 584 /* The target_wait operation waits for a process event to occur, and
 585    thereby stop the process.
 586
 587    On some targets, certain events may happen in sequences.  gdb's
 588    correct response to any single event of such a sequence may require
 589    knowledge of what earlier events in the sequence have been seen.
 590
 591    This operation provides a target-specific hook that allows the
 592    necessary bookkeeping to be performed to track such sequences.  */
 593
 594 #define target_post_wait(pid, status) \
 595      (*current_target.to_post_wait) (pid, status)
 596
 597 /* Fetch register REGNO, or all regs if regno == -1.  No result.  */
 598
 599 #define target_fetch_registers(regno)   \
 600      (*current_target.to_fetch_registers) (regno)
 601
 602 /* Store at least register REGNO, or all regs if REGNO == -1.
 603    It can store as many registers as it wants to, so target_prepare_to_store
 604    must have been previously called.  Calls error() if there are problems.  */
 605
 606 #define target_store_registers(regs)    \
 607      (*current_target.to_store_registers) (regs)
 608
 609 /* Get ready to modify the registers array.  On machines which store
 610    individual registers, this doesn't need to do anything.  On machines
 611    which store all the registers in one fell swoop, this makes sure
 612    that REGISTERS contains all the registers from the program being
 613    debugged.  */
 614
 615 #define target_prepare_to_store()       \
 616      (*current_target.to_prepare_to_store) ()
 617
 618 extern DCACHE *target_dcache;
 619
 620 extern int do_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write);
 621
 622 extern int target_read_string (CORE_ADDR, char **, int, int *);
 623
 624 extern int target_read_memory (CORE_ADDR memaddr, char *myaddr, int len);
 625
 626 extern int target_write_memory (CORE_ADDR memaddr, char *myaddr, int len);
 627
 628 extern int xfer_memory (CORE_ADDR, char *, int, int, struct target_ops *);
 629
 630 extern int
 631 child_xfer_memory (CORE_ADDR, char *, int, int, struct target_ops *);
 632
 633 /* Make a single attempt at transfering LEN bytes.  On a successful
 634    transfer, the number of bytes actually transfered is returned and
 635    ERR is set to 0.  When a transfer fails, -1 is returned (the number
 636    of bytes actually transfered is not defined) and ERR is set to a
 637    non-zero error indication.  */
 638
 639 extern int
 640 target_read_memory_partial (CORE_ADDR addr, char *buf, int len, int *err);
 641
 642 extern int
 643 target_write_memory_partial (CORE_ADDR addr, char *buf, int len, int *err);
 644
 645 extern char *child_pid_to_exec_file (int);
 646
 647 extern char *child_core_file_to_sym_file (char *);
 648
 649 #if defined(CHILD_POST_ATTACH)
 650 extern void child_post_attach (int);
 651 #endif
 652
 653 extern void child_post_wait (int, int);
 654
 655 extern void child_post_startup_inferior (int);
 656
 657 extern void child_acknowledge_created_inferior (int);
 658
 659 extern void child_clone_and_follow_inferior (int, int *);
 660
 661 extern void child_post_follow_inferior_by_clone (void);
 662
 663 extern int child_insert_fork_catchpoint (int);
 664
 665 extern int child_remove_fork_catchpoint (int);
 666
 667 extern int child_insert_vfork_catchpoint (int);
 668
 669 extern int child_remove_vfork_catchpoint (int);
 670
 671 extern int child_has_forked (int, int *);
 672
 673 extern int child_has_vforked (int, int *);
 674
 675 extern void child_acknowledge_created_inferior (int);
 676
 677 extern int child_can_follow_vfork_prior_to_exec (void);
 678
 679 extern void child_post_follow_vfork (int, int, int, int);
 680
 681 extern int child_insert_exec_catchpoint (int);
 682
 683 extern int child_remove_exec_catchpoint (int);
 684
 685 extern int child_has_execd (int, char **);
 686
 687 extern int child_reported_exec_events_per_exec_call (void);
 688
 689 extern int child_has_syscall_event (int, enum target_waitkind *, int *);
 690
 691 extern int child_has_exited (int, int, int *);
 692
 693 extern int child_thread_alive (int);
 694
 695 /* From exec.c */
 696
 697 extern void print_section_info (struct target_ops *, bfd *);
 698
 699 /* Print a line about the current target.  */
 700
 701 #define target_files_info()     \
 702      (*current_target.to_files_info) (&current_target)
 703
 704 /* Insert a breakpoint at address ADDR in the target machine.
 705    SAVE is a pointer to memory allocated for saving the
 706    target contents.  It is guaranteed by the caller to be long enough
 707    to save "sizeof BREAKPOINT" bytes.  Result is 0 for success, or
 708    an errno value.  */
 709
 710 #define target_insert_breakpoint(addr, save)    \
 711      (*current_target.to_insert_breakpoint) (addr, save)
 712
 713 /* Remove a breakpoint at address ADDR in the target machine.
 714    SAVE is a pointer to the same save area
 715    that was previously passed to target_insert_breakpoint.
 716    Result is 0 for success, or an errno value.  */
 717
 718 #define target_remove_breakpoint(addr, save)    \
 719      (*current_target.to_remove_breakpoint) (addr, save)
 720
 721 /* Initialize the terminal settings we record for the inferior,
 722    before we actually run the inferior.  */
 723
 724 #define target_terminal_init() \
 725      (*current_target.to_terminal_init) ()
 726
 727 /* Put the inferior's terminal settings into effect.
 728    This is preparation for starting or resuming the inferior.  */
 729
 730 #define target_terminal_inferior() \
 731      (*current_target.to_terminal_inferior) ()
 732
 733 /* Put some of our terminal settings into effect,
 734    enough to get proper results from our output,
 735    but do not change into or out of RAW mode
 736    so that no input is discarded.
 737
 738    After doing this, either terminal_ours or terminal_inferior
 739    should be called to get back to a normal state of affairs.  */
 740
 741 #define target_terminal_ours_for_output() \
 742      (*current_target.to_terminal_ours_for_output) ()
 743
 744 /* Put our terminal settings into effect.
 745    First record the inferior's terminal settings
 746    so they can be restored properly later.  */
 747
 748 #define target_terminal_ours() \
 749      (*current_target.to_terminal_ours) ()
 750
 751 /* Print useful information about our terminal status, if such a thing
 752    exists.  */
 753
 754 #define target_terminal_info(arg, from_tty) \
 755      (*current_target.to_terminal_info) (arg, from_tty)
 756
 757 /* Kill the inferior process.   Make it go away.  */
 758
 759 #define target_kill() \
 760      (*current_target.to_kill) ()
 761
 762 /* Load an executable file into the target process.  This is expected
 763    to not only bring new code into the target process, but also to
 764    update GDB's symbol tables to match.  */
 765
 766 extern void target_load (char *arg, int from_tty);
 767
 768 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 769    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 770    symbol should be returned.  The result is 0 if successful, nonzero
 771    if the symbol does not exist in the target environment.  This
 772    function should not call error() if communication with the target
 773    is interrupted, since it is called from symbol reading, but should
 774    return nonzero, possibly doing a complain().  */
 775
 776 #define target_lookup_symbol(name, addrp) \
 777      (*current_target.to_lookup_symbol) (name, addrp)
 778
 779 /* Start an inferior process and set inferior_pid to its pid.
 780    EXEC_FILE is the file to run.
 781    ALLARGS is a string containing the arguments to the program.
 782    ENV is the environment vector to pass.  Errors reported with error().
 783    On VxWorks and various standalone systems, we ignore exec_file.  */
 784
 785 #define target_create_inferior(exec_file, args, env)    \
 786      (*current_target.to_create_inferior) (exec_file, args, env)
 787
 788
 789 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 790    notification of inferior events such as fork and vork immediately
 791    after the inferior is created.  (This because of how gdb gets an
 792    inferior created via invoking a shell to do it.  In such a scenario,
 793    if the shell init file has commands in it, the shell will fork and
 794    exec for each of those commands, and we will see each such fork
 795    event.  Very bad.)
 796
 797    Such targets will supply an appropriate definition for this function.  */
 798
 799 #define target_post_startup_inferior(pid) \
 800      (*current_target.to_post_startup_inferior) (pid)
 801
 802 /* On some targets, the sequence of starting up an inferior requires
 803    some synchronization between gdb and the new inferior process, PID.  */
 804
 805 #define target_acknowledge_created_inferior(pid) \
 806      (*current_target.to_acknowledge_created_inferior) (pid)
 807
 808 /* An inferior process has been created via a fork() or similar
 809    system call.  This function will clone the debugger, then ensure
 810    that CHILD_PID is attached to by that debugger.
 811
 812    FOLLOWED_CHILD is set TRUE on return *for the clone debugger only*,
 813    and FALSE otherwise.  (The original and clone debuggers can use this
 814    to determine which they are, if need be.)
 815
 816    (This is not a terribly useful feature without a GUI to prevent
 817    the two debuggers from competing for shell input.)  */
 818
 819 #define target_clone_and_follow_inferior(child_pid,followed_child) \
 820      (*current_target.to_clone_and_follow_inferior) (child_pid, followed_child)
 821
 822 /* This operation is intended to be used as the last in a sequence of
 823    steps taken when following both parent and child of a fork.  This
 824    is used by a clone of the debugger, which will follow the child.
 825
 826    The original debugger has detached from this process, and the
 827    clone has attached to it.
 828
 829    On some targets, this requires a bit of cleanup to make it work
 830    correctly.  */
 831
 832 #define target_post_follow_inferior_by_clone() \
 833      (*current_target.to_post_follow_inferior_by_clone) ()
 834
 835 /* On some targets, we can catch an inferior fork or vfork event when
 836    it occurs.  These functions insert/remove an already-created
 837    catchpoint for such events.  */
 838
 839 #define target_insert_fork_catchpoint(pid) \
 840      (*current_target.to_insert_fork_catchpoint) (pid)
 841
 842 #define target_remove_fork_catchpoint(pid) \
 843      (*current_target.to_remove_fork_catchpoint) (pid)
 844
 845 #define target_insert_vfork_catchpoint(pid) \
 846      (*current_target.to_insert_vfork_catchpoint) (pid)
 847
 848 #define target_remove_vfork_catchpoint(pid) \
 849      (*current_target.to_remove_vfork_catchpoint) (pid)
 850
 851 /* Returns TRUE if PID has invoked the fork() system call.  And,
 852    also sets CHILD_PID to the process id of the other ("child")
 853    inferior process that was created by that call.  */
 854
 855 #define target_has_forked(pid,child_pid) \
 856      (*current_target.to_has_forked) (pid,child_pid)
 857
 858 /* Returns TRUE if PID has invoked the vfork() system call.  And,
 859    also sets CHILD_PID to the process id of the other ("child")
 860    inferior process that was created by that call.  */
 861
 862 #define target_has_vforked(pid,child_pid) \
 863      (*current_target.to_has_vforked) (pid,child_pid)
 864
 865 /* Some platforms (such as pre-10.20 HP-UX) don't allow us to do
 866    anything to a vforked child before it subsequently calls exec().
 867    On such platforms, we say that the debugger cannot "follow" the
 868    child until it has vforked.
 869
 870    This function should be defined to return 1 by those targets
 871    which can allow the debugger to immediately follow a vforked
 872    child, and 0 if they cannot.  */
 873
 874 #define target_can_follow_vfork_prior_to_exec() \
 875      (*current_target.to_can_follow_vfork_prior_to_exec) ()
 876
 877 /* An inferior process has been created via a vfork() system call.
 878    The debugger has followed the parent, the child, or both.  The
 879    process of setting up for that follow may have required some
 880    target-specific trickery to track the sequence of reported events.
 881    If so, this function should be defined by those targets that
 882    require the debugger to perform cleanup or initialization after
 883    the vfork follow.  */
 884
 885 #define target_post_follow_vfork(parent_pid,followed_parent,child_pid,followed_child) \
 886      (*current_target.to_post_follow_vfork) (parent_pid,followed_parent,child_pid,followed_child)
 887
 888 /* On some targets, we can catch an inferior exec event when it
 889    occurs.  These functions insert/remove an already-created
 890    catchpoint for such events.  */
 891
 892 #define target_insert_exec_catchpoint(pid) \
 893      (*current_target.to_insert_exec_catchpoint) (pid)
 894
 895 #define target_remove_exec_catchpoint(pid) \
 896      (*current_target.to_remove_exec_catchpoint) (pid)
 897
 898 /* Returns TRUE if PID has invoked a flavor of the exec() system call.
 899    And, also sets EXECD_PATHNAME to the pathname of the executable
 900    file that was passed to exec(), and is now being executed.  */
 901
 902 #define target_has_execd(pid,execd_pathname) \
 903      (*current_target.to_has_execd) (pid,execd_pathname)
 904
 905 /* Returns the number of exec events that are reported when a process
 906    invokes a flavor of the exec() system call on this target, if exec
 907    events are being reported.  */
 908
 909 #define target_reported_exec_events_per_exec_call() \
 910      (*current_target.to_reported_exec_events_per_exec_call) ()
 911
 912 /* Returns TRUE if PID has reported a syscall event.  And, also sets
 913    KIND to the appropriate TARGET_WAITKIND_, and sets SYSCALL_ID to
 914    the unique integer ID of the syscall.  */
 915
 916 #define target_has_syscall_event(pid,kind,syscall_id) \
 917      (*current_target.to_has_syscall_event) (pid,kind,syscall_id)
 918
 919 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 920    exit code of PID, if any.  */
 921
 922 #define target_has_exited(pid,wait_status,exit_status) \
 923      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 924
 925 /* The debugger has completed a blocking wait() call.  There is now
 926    some process event that must be processed.  This function should
 927    be defined by those targets that require the debugger to perform
 928    cleanup or internal state changes in response to the process event.  */
 929
 930 /* The inferior process has died.  Do what is right.  */
 931
 932 #define target_mourn_inferior() \
 933      (*current_target.to_mourn_inferior) ()
 934
 935 /* Does target have enough data to do a run or attach command? */
 936
 937 #define target_can_run(t) \
 938      ((t)->to_can_run) ()
 939
 940 /* post process changes to signal handling in the inferior.  */
 941
 942 #define target_notice_signals(pid) \
 943      (*current_target.to_notice_signals) (pid)
 944
 945 /* Check to see if a thread is still alive.  */
 946
 947 #define target_thread_alive(pid) \
 948      (*current_target.to_thread_alive) (pid)
 949
 950 /* Query for new threads and add them to the thread list.  */
 951
 952 #define target_find_new_threads() \
 953      (*current_target.to_find_new_threads) (); \
 954
 955 /* Make target stop in a continuable fashion.  (For instance, under
 956    Unix, this should act like SIGSTOP).  This function is normally
 957    used by GUIs to implement a stop button.  */
 958
 959 #define target_stop current_target.to_stop
 960
 961 /* Queries the target side for some information.  The first argument is a
 962    letter specifying the type of the query, which is used to determine who
 963    should process it.  The second argument is a string that specifies which
 964    information is desired and the third is a buffer that carries back the
 965    response from the target side. The fourth parameter is the size of the
 966    output buffer supplied.  */
 967
 968 #define target_query(query_type, query, resp_buffer, bufffer_size)      \
 969      (*current_target.to_query) (query_type, query, resp_buffer, bufffer_size)
 970
 971 /* Send the specified COMMAND to the target's monitor
 972    (shell,interpreter) for execution.  The result of the query is
 973    placed in OUTBUF.  */
 974
 975 #define target_rcmd(command, outbuf) \
 976      (*current_target.to_rcmd) (command, outbuf)
 977
 978
 979 /* Get the symbol information for a breakpointable routine called when
 980    an exception event occurs.
 981    Intended mainly for C++, and for those
 982    platforms/implementations where such a callback mechanism is available,
 983    e.g. HP-UX with ANSI C++ (aCC).  Some compilers (e.g. g++) support
 984    different mechanisms for debugging exceptions.  */
 985
 986 #define target_enable_exception_callback(kind, enable) \
 987      (*current_target.to_enable_exception_callback) (kind, enable)
 988
 989 /* Get the current exception event kind -- throw or catch, etc.  */
 990
 991 #define target_get_current_exception_event() \
 992      (*current_target.to_get_current_exception_event) ()
 993
 994 /* Pointer to next target in the chain, e.g. a core file and an exec file.  */
 995
 996 #define target_next \
 997      (current_target.to_next)
 998
 999 /* Does the target include all of memory, or only part of it?  This
1000    determines whether we look up the target chain for other parts of
1001    memory if this target can't satisfy a request.  */
1002
1003 #define target_has_all_memory   \
1004      (current_target.to_has_all_memory)
1005
1006 /* Does the target include memory?  (Dummy targets don't.)  */
1007
1008 #define target_has_memory       \
1009      (current_target.to_has_memory)
1010
1011 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
1012    we start a process.)  */
1013
1014 #define target_has_stack        \
1015      (current_target.to_has_stack)
1016
1017 /* Does the target have registers?  (Exec files don't.)  */
1018
1019 #define target_has_registers    \
1020      (current_target.to_has_registers)
1021
1022 /* Does the target have execution?  Can we make it jump (through
1023    hoops), or pop its stack a few times?  FIXME: If this is to work that
1024    way, it needs to check whether an inferior actually exists.
1025    remote-udi.c and probably other targets can be the current target
1026    when the inferior doesn't actually exist at the moment.  Right now
1027    this just tells us whether this target is *capable* of execution.  */
1028
1029 #define target_has_execution    \
1030      (current_target.to_has_execution)
1031
1032 /* Can the target support the debugger control of thread execution?
1033    a) Can it lock the thread scheduler?
1034    b) Can it switch the currently running thread?  */
1035
1036 #define target_can_lock_scheduler \
1037      (current_target.to_has_thread_control & tc_schedlock)
1038
1039 #define target_can_switch_threads \
1040      (current_target.to_has_thread_control & tc_switch)
1041
1042 /* Can the target support asynchronous execution? */
1043 #define target_can_async_p() (current_target.to_can_async_p ())
1044
1045 /* Is the target in asynchronous execution mode? */
1046 #define target_is_async_p() (current_target.to_is_async_p())
1047
1048 /* Put the target in async mode with the specified callback function. */
1049 #define target_async(CALLBACK,CONTEXT) \
1050      (current_target.to_async((CALLBACK), (CONTEXT)))
1051
1052 /* This is to be used ONLY within run_stack_dummy(). It
1053    provides a workaround, to have inferior function calls done in
1054    sychronous mode, even though the target is asynchronous. After
1055    target_async_mask(0) is called, calls to target_can_async_p() will
1056    return FALSE , so that target_resume() will not try to start the
1057    target asynchronously. After the inferior stops, we IMMEDIATELY
1058    restore the previous nature of the target, by calling
1059    target_async_mask(1). After that, target_can_async_p() will return
1060    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
1061
1062    FIXME ezannoni 1999-12-13: we won't need this once we move
1063    the turning async on and off to the single execution commands,
1064    from where it is done currently, in remote_resume().  */
1065
1066 #define target_async_mask_value \
1067      (current_target.to_async_mask_value)
1068
1069 extern int target_async_mask (int mask);
1070
1071 extern void target_link (char *, CORE_ADDR *);
1072
1073 /* Converts a process id to a string.  Usually, the string just contains
1074    `process xyz', but on some systems it may contain
1075    `process xyz thread abc'.  */
1076
1077 #undef target_pid_to_str
1078 #define target_pid_to_str(PID) current_target.to_pid_to_str (PID)
1079
1080 #ifndef target_tid_to_str
1081 #define target_tid_to_str(PID) \
1082      target_pid_to_str (PID)
1083 extern char *normal_pid_to_str (int pid);
1084 #endif
1085
1086 /* Return a short string describing extra information about PID,
1087    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1088    is okay.  */
1089
1090 #define target_extra_thread_info(TP) \
1091      (current_target.to_extra_thread_info (TP))
1092
1093 /*
1094  * New Objfile Event Hook:
1095  *
1096  * Sometimes a GDB component wants to get notified whenever a new
1097  * objfile is loaded.  Mainly this is used by thread-debugging
1098  * implementations that need to know when symbols for the target
1099  * thread implemenation are available.
1100  *
1101  * The old way of doing this is to define a macro 'target_new_objfile'
1102  * that points to the function that you want to be called on every
1103  * objfile/shlib load.
1104  *
1105  * The new way is to grab the function pointer, 'target_new_objfile_hook',
1106  * and point it to the function that you want to be called on every
1107  * objfile/shlib load.
1108  *
1109  * If multiple clients are willing to be cooperative, they can each
1110  * save a pointer to the previous value of target_new_objfile_hook
1111  * before modifying it, and arrange for their function to call the
1112  * previous function in the chain.  In that way, multiple clients
1113  * can receive this notification (something like with signal handlers).
1114  */
1115
1116 extern void (*target_new_objfile_hook) (struct objfile *);
1117
1118 #ifndef target_pid_or_tid_to_str
1119 #define target_pid_or_tid_to_str(ID) \
1120      target_pid_to_str (ID)
1121 #endif
1122
1123 /* Attempts to find the pathname of the executable file
1124    that was run to create a specified process.
1125
1126    The process PID must be stopped when this operation is used.
1127
1128    If the executable file cannot be determined, NULL is returned.
1129
1130    Else, a pointer to a character string containing the pathname
1131    is returned.  This string should be copied into a buffer by
1132    the client if the string will not be immediately used, or if
1133    it must persist.  */
1134
1135 #define target_pid_to_exec_file(pid) \
1136      (current_target.to_pid_to_exec_file) (pid)
1137
1138 /* Hook to call target-dependent code after reading in a new symbol table.  */
1139
1140 #ifndef TARGET_SYMFILE_POSTREAD
1141 #define TARGET_SYMFILE_POSTREAD(OBJFILE)
1142 #endif
1143
1144 /* Hook to call target dependent code just after inferior target process has
1145    started.  */
1146
1147 #ifndef TARGET_CREATE_INFERIOR_HOOK
1148 #define TARGET_CREATE_INFERIOR_HOOK(PID)
1149 #endif
1150
1151 /* Hardware watchpoint interfaces.  */
1152
1153 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1154    write).  */
1155
1156 #ifndef STOPPED_BY_WATCHPOINT
1157 #define STOPPED_BY_WATCHPOINT(w) 0
1158 #endif
1159
1160 /* HP-UX supplies these operations, which respectively disable and enable
1161    the memory page-protections that are used to implement hardware watchpoints
1162    on that platform.  See wait_for_inferior's use of these.  */
1163
1164 #if !defined(TARGET_DISABLE_HW_WATCHPOINTS)
1165 #define TARGET_DISABLE_HW_WATCHPOINTS(pid)
1166 #endif
1167
1168 #if !defined(TARGET_ENABLE_HW_WATCHPOINTS)
1169 #define TARGET_ENABLE_HW_WATCHPOINTS(pid)
1170 #endif
1171
1172 /* Provide defaults for systems that don't support hardware watchpoints.  */
1173
1174 #ifndef TARGET_HAS_HARDWARE_WATCHPOINTS
1175
1176 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1177    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1178    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1179    (including this one?).  OTHERTYPE is who knows what...  */
1180
1181 #define TARGET_CAN_USE_HARDWARE_WATCHPOINT(TYPE,CNT,OTHERTYPE) 0
1182
1183 #if !defined(TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT)
1184 #define TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT(byte_count) \
1185      (LONGEST)(byte_count) <= REGISTER_SIZE
1186 #endif
1187
1188 /* However, some addresses may not be profitable to use hardware to watch,
1189    or may be difficult to understand when the addressed object is out of
1190    scope, and hence should be unwatched.  On some targets, this may have
1191    severe performance penalties, such that we might as well use regular
1192    watchpoints, and save (possibly precious) hardware watchpoints for other
1193    locations.  */
1194
1195 #if !defined(TARGET_RANGE_PROFITABLE_FOR_HW_WATCHPOINT)
1196 #define TARGET_RANGE_PROFITABLE_FOR_HW_WATCHPOINT(pid,start,len) 0
1197 #endif
1198
1199
1200 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1201    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1202    success, non-zero for failure.  */
1203
1204 #define target_remove_watchpoint(ADDR,LEN,TYPE) -1
1205 #define target_insert_watchpoint(ADDR,LEN,TYPE) -1
1206
1207 #endif /* TARGET_HAS_HARDWARE_WATCHPOINTS */
1208
1209 #ifndef target_insert_hw_breakpoint
1210 #define target_remove_hw_breakpoint(ADDR,SHADOW) -1
1211 #define target_insert_hw_breakpoint(ADDR,SHADOW) -1
1212 #endif
1213
1214 #ifndef target_stopped_data_address
1215 #define target_stopped_data_address() 0
1216 #endif
1217
1218 /* If defined, then we need to decr pc by this much after a hardware break-
1219    point.  Presumably this overrides DECR_PC_AFTER_BREAK...  */
1220
1221 #ifndef DECR_PC_AFTER_HW_BREAK
1222 #define DECR_PC_AFTER_HW_BREAK 0
1223 #endif
1224
1225 /* Sometimes gdb may pick up what appears to be a valid target address
1226    from a minimal symbol, but the value really means, essentially,
1227    "This is an index into a table which is populated when the inferior
1228    is run.  Therefore, do not attempt to use this as a PC."  */
1229
1230 #if !defined(PC_REQUIRES_RUN_BEFORE_USE)
1231 #define PC_REQUIRES_RUN_BEFORE_USE(pc) (0)
1232 #endif
1233
1234 /* This will only be defined by a target that supports catching vfork events,
1235    such as HP-UX.
1236
1237    On some targets (such as HP-UX 10.20 and earlier), resuming a newly vforked
1238    child process after it has exec'd, causes the parent process to resume as
1239    well.  To prevent the parent from running spontaneously, such targets should
1240    define this to a function that prevents that from happening.  */
1241 #if !defined(ENSURE_VFORKING_PARENT_REMAINS_STOPPED)
1242 #define ENSURE_VFORKING_PARENT_REMAINS_STOPPED(PID) (0)
1243 #endif
1244
1245 /* This will only be defined by a target that supports catching vfork events,
1246    such as HP-UX.
1247
1248    On some targets (such as HP-UX 10.20 and earlier), a newly vforked child
1249    process must be resumed when it delivers its exec event, before the parent
1250    vfork event will be delivered to us.  */
1251
1252 #if !defined(RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK)
1253 #define RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK() (0)
1254 #endif
1255
1256 /* Routines for maintenance of the target structures...
1257
1258    add_target:   Add a target to the list of all possible targets.
1259
1260    push_target:  Make this target the top of the stack of currently used
1261    targets, within its particular stratum of the stack.  Result
1262    is 0 if now atop the stack, nonzero if not on top (maybe
1263    should warn user).
1264
1265    unpush_target: Remove this from the stack of currently used targets,
1266    no matter where it is on the list.  Returns 0 if no
1267    change, 1 if removed from stack.
1268
1269    pop_target:   Remove the top thing on the stack of current targets.  */
1270
1271 extern void add_target (struct target_ops *);
1272
1273 extern int push_target (struct target_ops *);
1274
1275 extern int unpush_target (struct target_ops *);
1276
1277 extern void target_preopen (int);
1278
1279 extern void pop_target (void);
1280
1281 /* Struct section_table maps address ranges to file sections.  It is
1282    mostly used with BFD files, but can be used without (e.g. for handling
1283    raw disks, or files not in formats handled by BFD).  */
1284
1285 struct section_table
1286   {
1287     CORE_ADDR addr;             /* Lowest address in section */
1288     CORE_ADDR endaddr;          /* 1+highest address in section */
1289
1290     sec_ptr the_bfd_section;
1291
1292     bfd *bfd;                   /* BFD file pointer */
1293   };
1294
1295 /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR.
1296    Returns 0 if OK, 1 on error.  */
1297
1298 extern int
1299 build_section_table (bfd *, struct section_table **, struct section_table **);
1300
1301 /* From mem-break.c */
1302
1303 extern int memory_remove_breakpoint (CORE_ADDR, char *);
1304
1305 extern int memory_insert_breakpoint (CORE_ADDR, char *);
1306
1307 extern int default_memory_remove_breakpoint (CORE_ADDR, char *);
1308
1309 extern int default_memory_insert_breakpoint (CORE_ADDR, char *);
1310
1311 extern breakpoint_from_pc_fn memory_breakpoint_from_pc;
1312
1313
1314 /* From target.c */
1315
1316 extern void initialize_targets (void);
1317
1318 extern void noprocess (void);
1319
1320 extern void find_default_attach (char *, int);
1321
1322 extern void find_default_require_attach (char *, int);
1323
1324 extern void find_default_require_detach (int, char *, int);
1325
1326 extern void find_default_create_inferior (char *, char *, char **);
1327
1328 extern void find_default_clone_and_follow_inferior (int, int *);
1329
1330 extern struct target_ops *find_run_target (void);
1331
1332 extern struct target_ops *find_core_target (void);
1333
1334 extern struct target_ops *find_target_beneath (struct target_ops *);
1335
1336 extern int
1337 target_resize_to_sections (struct target_ops *target, int num_added);
1338
1339 extern void remove_target_sections (bfd *abfd);
1340
1341 \f
1342 /* Stuff that should be shared among the various remote targets.  */
1343
1344 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1345    information (higher values, more information).  */
1346 extern int remote_debug;
1347
1348 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1349 extern int baud_rate;
1350 /* Timeout limit for response from target. */
1351 extern int remote_timeout;
1352
1353 \f
1354 /* Functions for helping to write a native target.  */
1355
1356 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1357 extern void store_waitstatus (struct target_waitstatus *, int);
1358
1359 /* Predicate to target_signal_to_host(). Return non-zero if the enum
1360    targ_signal SIGNO has an equivalent ``host'' representation.  */
1361 /* FIXME: cagney/1999-11-22: The name below was chosen in preference
1362    to the shorter target_signal_p() because it is far less ambigious.
1363    In this context ``target_signal'' refers to GDB's internal
1364    representation of the target's set of signals while ``host signal''
1365    refers to the target operating system's signal.  Confused?  */
1366
1367 extern int target_signal_to_host_p (enum target_signal signo);
1368
1369 /* Convert between host signal numbers and enum target_signal's.
1370    target_signal_to_host() returns 0 and prints a warning() on GDB's
1371    console if SIGNO has no equivalent host representation.  */
1372 /* FIXME: cagney/1999-11-22: Here ``host'' is used incorrectly, it is
1373    refering to the target operating system's signal numbering.
1374    Similarly, ``enum target_signal'' is named incorrectly, ``enum
1375    gdb_signal'' would probably be better as it is refering to GDB's
1376    internal representation of a target operating system's signal.  */
1377
1378 extern enum target_signal target_signal_from_host (int);
1379 extern int target_signal_to_host (enum target_signal);
1380
1381 /* Convert from a number used in a GDB command to an enum target_signal.  */
1382 extern enum target_signal target_signal_from_command (int);
1383
1384 /* Any target can call this to switch to remote protocol (in remote.c). */
1385 extern void push_remote_target (char *name, int from_tty);
1386 \f
1387 /* Imported from machine dependent code */
1388
1389 #ifndef SOFTWARE_SINGLE_STEP_P
1390 #define SOFTWARE_SINGLE_STEP_P 0
1391 #define SOFTWARE_SINGLE_STEP(sig,bp_p)  \
1392      (internal_error ("SOFTWARE_SINGLE_STEP"), 0)
1393 #endif /* SOFTWARE_SINGLE_STEP_P */
1394
1395 /* Blank target vector entries are initialized to target_ignore. */
1396 void target_ignore (void);
1397
1398 /* Macro for getting target's idea of a frame pointer.
1399    FIXME: GDB's whole scheme for dealing with "frames" and
1400    "frame pointers" needs a serious shakedown.  */
1401 #ifndef TARGET_VIRTUAL_FRAME_POINTER
1402 #define TARGET_VIRTUAL_FRAME_POINTER(ADDR, REGP, OFFP) \
1403    do { *(REGP) = FP_REGNUM; *(OFFP) =  0; } while (0)
1404 #endif /* TARGET_VIRTUAL_FRAME_POINTER */
1405
1406 #endif /* !defined (TARGET_H) */