gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2
   3    Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   4    1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   5
   6    Contributed by Cygnus Support.  Written by John Gilmore.
   7
   8    This file is part of GDB.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330,
  23    Boston, MA 02111-1307, USA.  */
  24
  25 #if !defined (TARGET_H)
  26 #define TARGET_H
  27
  28 struct objfile;
  29 struct ui_file;
  30 struct mem_attrib;
  31 struct target_ops;
  32
  33 /* This include file defines the interface between the main part
  34    of the debugger, and the part which is target-specific, or
  35    specific to the communications interface between us and the
  36    target.
  37
  38    A TARGET is an interface between the debugger and a particular
  39    kind of file or process.  Targets can be STACKED in STRATA,
  40    so that more than one target can potentially respond to a request.
  41    In particular, memory accesses will walk down the stack of targets
  42    until they find a target that is interested in handling that particular
  43    address.  STRATA are artificial boundaries on the stack, within
  44    which particular kinds of targets live.  Strata exist so that
  45    people don't get confused by pushing e.g. a process target and then
  46    a file target, and wondering why they can't see the current values
  47    of variables any more (the file target is handling them and they
  48    never get to the process target).  So when you push a file target,
  49    it goes into the file stratum, which is always below the process
  50    stratum.  */
  51
  52 #include "bfd.h"
  53 #include "symtab.h"
  54 #include "dcache.h"
  55 #include "memattr.h"
  56
  57 enum strata
  58   {
  59     dummy_stratum,              /* The lowest of the low */
  60     file_stratum,               /* Executable files, etc */
  61     core_stratum,               /* Core dump files */
  62     download_stratum,           /* Downloading of remote targets */
  63     process_stratum,            /* Executing processes */
  64     thread_stratum              /* Executing threads */
  65   };
  66
  67 enum thread_control_capabilities
  68   {
  69     tc_none = 0,                /* Default: can't control thread execution.  */
  70     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  71     tc_switch = 2               /* Can switch the running thread on demand.  */
  72   };
  73
  74 /* Stuff for target_wait.  */
  75
  76 /* Generally, what has the program done?  */
  77 enum target_waitkind
  78   {
  79     /* The program has exited.  The exit status is in value.integer.  */
  80     TARGET_WAITKIND_EXITED,
  81
  82     /* The program has stopped with a signal.  Which signal is in
  83        value.sig.  */
  84     TARGET_WAITKIND_STOPPED,
  85
  86     /* The program has terminated with a signal.  Which signal is in
  87        value.sig.  */
  88     TARGET_WAITKIND_SIGNALLED,
  89
  90     /* The program is letting us know that it dynamically loaded something
  91        (e.g. it called load(2) on AIX).  */
  92     TARGET_WAITKIND_LOADED,
  93
  94     /* The program has forked.  A "related" process' ID is in
  95        value.related_pid.  I.e., if the child forks, value.related_pid
  96        is the parent's ID.  */
  97
  98     TARGET_WAITKIND_FORKED,
  99
 100     /* The program has vforked.  A "related" process's ID is in
 101        value.related_pid.  */
 102
 103     TARGET_WAITKIND_VFORKED,
 104
 105     /* The program has exec'ed a new executable file.  The new file's
 106        pathname is pointed to by value.execd_pathname.  */
 107
 108     TARGET_WAITKIND_EXECD,
 109
 110     /* The program has entered or returned from a system call.  On
 111        HP-UX, this is used in the hardware watchpoint implementation.
 112        The syscall's unique integer ID number is in value.syscall_id */
 113
 114     TARGET_WAITKIND_SYSCALL_ENTRY,
 115     TARGET_WAITKIND_SYSCALL_RETURN,
 116
 117     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 118        within target_wait, but I'm not sure target_wait should be resuming the
 119        inferior.  */
 120     TARGET_WAITKIND_SPURIOUS,
 121
 122     /* An event has occured, but we should wait again.
 123        Remote_async_wait() returns this when there is an event
 124        on the inferior, but the rest of the world is not interested in
 125        it. The inferior has not stopped, but has just sent some output
 126        to the console, for instance. In this case, we want to go back
 127        to the event loop and wait there for another event from the
 128        inferior, rather than being stuck in the remote_async_wait()
 129        function. This way the event loop is responsive to other events,
 130        like for instance the user typing.  */
 131     TARGET_WAITKIND_IGNORE
 132   };
 133
 134 struct target_waitstatus
 135   {
 136     enum target_waitkind kind;
 137
 138     /* Forked child pid, execd pathname, exit status or signal number.  */
 139     union
 140       {
 141         int integer;
 142         enum target_signal sig;
 143         int related_pid;
 144         char *execd_pathname;
 145         int syscall_id;
 146       }
 147     value;
 148   };
 149
 150 /* Possible types of events that the inferior handler will have to
 151    deal with.  */
 152 enum inferior_event_type
 153   {
 154     /* There is a request to quit the inferior, abandon it.  */
 155     INF_QUIT_REQ,
 156     /* Process a normal inferior event which will result in target_wait
 157        being called.  */
 158     INF_REG_EVENT,
 159     /* Deal with an error on the inferior.  */
 160     INF_ERROR,
 161     /* We are called because a timer went off.  */
 162     INF_TIMER,
 163     /* We are called to do stuff after the inferior stops.  */
 164     INF_EXEC_COMPLETE,
 165     /* We are called to do some stuff after the inferior stops, but we
 166        are expected to reenter the proceed() and
 167        handle_inferior_event() functions. This is used only in case of
 168        'step n' like commands.  */
 169     INF_EXEC_CONTINUE
 170   };
 171
 172 /* Return the string for a signal.  */
 173 extern char *target_signal_to_string (enum target_signal);
 174
 175 /* Return the name (SIGHUP, etc.) for a signal.  */
 176 extern char *target_signal_to_name (enum target_signal);
 177
 178 /* Given a name (SIGHUP, etc.), return its signal.  */
 179 enum target_signal target_signal_from_name (char *);
 180 \f
 181 /* Request the transfer of up to LEN 8-bit bytes of the target's
 182    OBJECT.  The OFFSET, for a seekable object, specifies the starting
 183    point.  The ANNEX can be used to provide additional data-specific
 184    information to the target.
 185
 186    Return the number of bytes actually transfered, zero when no
 187    further transfer is possible, and -1 when the transfer is not
 188    supported.
 189
 190    NOTE: cagney/2003-10-17: The current interface does not support a
 191    "retry" mechanism.  Instead it assumes that at least one byte will
 192    be transfered on each call.
 193
 194    NOTE: cagney/2003-10-17: The current interface can lead to
 195    fragmented transfers.  Lower target levels should not implement
 196    hacks, such as enlarging the transfer, in an attempt to compensate
 197    for this.  Instead, the target stack should be extended so that it
 198    implements supply/collect methods and a look-aside object cache.
 199    With that available, the lowest target can safely and freely "push"
 200    data up the stack.
 201
 202    NOTE: cagney/2003-10-17: Unlike the old query and the memory
 203    transfer mechanisms, these methods are explicitly parameterized by
 204    the target that it should be applied to.
 205
 206    NOTE: cagney/2003-10-17: Just like the old query and memory xfer
 207    methods, these new methods perform partial transfers.  The only
 208    difference is that these new methods thought to include "partial"
 209    in the name.  The old code's failure to do this lead to much
 210    confusion and duplication of effort as each target object attempted
 211    to locally take responsibility for something it didn't have to
 212    worry about.
 213
 214    NOTE: cagney/2003-10-17: With a TARGET_OBJECT_KOD object, for
 215    backward compatibility with the "target_query" method that this
 216    replaced, when OFFSET and LEN are both zero, return the "minimum"
 217    buffer size.  See "remote.c" for further information.  */
 218
 219 enum target_object
 220 {
 221   /* Kernel Object Display transfer.  See "kod.c" and "remote.c".  */
 222   TARGET_OBJECT_KOD,
 223   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 224   TARGET_OBJECT_AVR,
 225   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 226   TARGET_OBJECT_MEMORY,
 227   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 228   TARGET_OBJECT_UNWIND_TABLE,
 229   /* Transfer auxilliary vector.  */
 230   TARGET_OBJECT_AUXV,
 231   /* StackGhost cookie.  See "sparc-tdep.c".  */
 232   TARGET_OBJECT_WCOOKIE
 233
 234   /* Possible future objects: TARGET_OBJECT_FILE, TARGET_OBJECT_PROC, ... */
 235 };
 236
 237 extern LONGEST target_read_partial (struct target_ops *ops,
 238                                     enum target_object object,
 239                                     const char *annex, void *buf,
 240                                     ULONGEST offset, LONGEST len);
 241
 242 extern LONGEST target_write_partial (struct target_ops *ops,
 243                                      enum target_object object,
 244                                      const char *annex, const void *buf,
 245                                      ULONGEST offset, LONGEST len);
 246
 247 /* Wrappers to perform the full transfer.  */
 248 extern LONGEST target_read (struct target_ops *ops,
 249                             enum target_object object,
 250                             const char *annex, void *buf,
 251                             ULONGEST offset, LONGEST len);
 252
 253 extern LONGEST target_write (struct target_ops *ops,
 254                              enum target_object object,
 255                              const char *annex, const void *buf,
 256                              ULONGEST offset, LONGEST len);
 257
 258 /* Wrappers to target read/write that perform memory transfers.  They
 259    throw an error if the memory transfer fails.
 260
 261    NOTE: cagney/2003-10-23: The naming schema is lifted from
 262    "frame.h".  The parameter order is lifted from get_frame_memory,
 263    which in turn lifted it from read_memory.  */
 264
 265 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 266                                void *buf, LONGEST len);
 267 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 268                                             CORE_ADDR addr, int len);
 269 \f
 270
 271 /* If certain kinds of activity happen, target_wait should perform
 272    callbacks.  */
 273 /* Right now we just call (*TARGET_ACTIVITY_FUNCTION) if I/O is possible
 274    on TARGET_ACTIVITY_FD.  */
 275 extern int target_activity_fd;
 276 /* Returns zero to leave the inferior alone, one to interrupt it.  */
 277 extern int (*target_activity_function) (void);
 278 \f
 279 struct thread_info;             /* fwd decl for parameter list below: */
 280
 281 struct target_ops
 282   {
 283     struct target_ops *beneath; /* To the target under this one.  */
 284     char *to_shortname;         /* Name this target type */
 285     char *to_longname;          /* Name for printing */
 286     char *to_doc;               /* Documentation.  Does not include trailing
 287                                    newline, and starts with a one-line descrip-
 288                                    tion (probably similar to to_longname).  */
 289     /* Per-target scratch pad.  */
 290     void *to_data;
 291     /* The open routine takes the rest of the parameters from the
 292        command, and (if successful) pushes a new target onto the
 293        stack.  Targets should supply this routine, if only to provide
 294        an error message.  */
 295     void (*to_open) (char *, int);
 296     /* Old targets with a static target vector provide "to_close".
 297        New re-entrant targets provide "to_xclose" and that is expected
 298        to xfree everything (including the "struct target_ops").  */
 299     void (*to_xclose) (struct target_ops *targ, int quitting);
 300     void (*to_close) (int);
 301     void (*to_attach) (char *, int);
 302     void (*to_post_attach) (int);
 303     void (*to_detach) (char *, int);
 304     void (*to_disconnect) (char *, int);
 305     void (*to_resume) (ptid_t, int, enum target_signal);
 306     ptid_t (*to_wait) (ptid_t, struct target_waitstatus *);
 307     void (*to_fetch_registers) (int);
 308     void (*to_store_registers) (int);
 309     void (*to_prepare_to_store) (void);
 310
 311     /* Transfer LEN bytes of memory between GDB address MYADDR and
 312        target address MEMADDR.  If WRITE, transfer them to the target, else
 313        transfer them from the target.  TARGET is the target from which we
 314        get this function.
 315
 316        Return value, N, is one of the following:
 317
 318        0 means that we can't handle this.  If errno has been set, it is the
 319        error which prevented us from doing it (FIXME: What about bfd_error?).
 320
 321        positive (call it N) means that we have transferred N bytes
 322        starting at MEMADDR.  We might be able to handle more bytes
 323        beyond this length, but no promises.
 324
 325        negative (call its absolute value N) means that we cannot
 326        transfer right at MEMADDR, but we could transfer at least
 327        something at MEMADDR + N.  */
 328
 329     int (*to_xfer_memory) (CORE_ADDR memaddr, char *myaddr,
 330                            int len, int write,
 331                            struct mem_attrib *attrib,
 332                            struct target_ops *target);
 333
 334     void (*to_files_info) (struct target_ops *);
 335     int (*to_insert_breakpoint) (CORE_ADDR, char *);
 336     int (*to_remove_breakpoint) (CORE_ADDR, char *);
 337     int (*to_can_use_hw_breakpoint) (int, int, int);
 338     int (*to_insert_hw_breakpoint) (CORE_ADDR, char *);
 339     int (*to_remove_hw_breakpoint) (CORE_ADDR, char *);
 340     int (*to_remove_watchpoint) (CORE_ADDR, int, int);
 341     int (*to_insert_watchpoint) (CORE_ADDR, int, int);
 342     int (*to_stopped_by_watchpoint) (void);
 343     int to_have_continuable_watchpoint;
 344     CORE_ADDR (*to_stopped_data_address) (void);
 345     int (*to_region_size_ok_for_hw_watchpoint) (int);
 346     void (*to_terminal_init) (void);
 347     void (*to_terminal_inferior) (void);
 348     void (*to_terminal_ours_for_output) (void);
 349     void (*to_terminal_ours) (void);
 350     void (*to_terminal_save_ours) (void);
 351     void (*to_terminal_info) (char *, int);
 352     void (*to_kill) (void);
 353     void (*to_load) (char *, int);
 354     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 355     void (*to_create_inferior) (char *, char *, char **, int);
 356     void (*to_post_startup_inferior) (ptid_t);
 357     void (*to_acknowledge_created_inferior) (int);
 358     int (*to_insert_fork_catchpoint) (int);
 359     int (*to_remove_fork_catchpoint) (int);
 360     int (*to_insert_vfork_catchpoint) (int);
 361     int (*to_remove_vfork_catchpoint) (int);
 362     int (*to_follow_fork) (int);
 363     int (*to_insert_exec_catchpoint) (int);
 364     int (*to_remove_exec_catchpoint) (int);
 365     int (*to_reported_exec_events_per_exec_call) (void);
 366     int (*to_has_exited) (int, int, int *);
 367     void (*to_mourn_inferior) (void);
 368     int (*to_can_run) (void);
 369     void (*to_notice_signals) (ptid_t ptid);
 370     int (*to_thread_alive) (ptid_t ptid);
 371     void (*to_find_new_threads) (void);
 372     char *(*to_pid_to_str) (ptid_t);
 373     char *(*to_extra_thread_info) (struct thread_info *);
 374     void (*to_stop) (void);
 375     void (*to_rcmd) (char *command, struct ui_file *output);
 376     struct symtab_and_line *(*to_enable_exception_callback) (enum
 377                                                              exception_event_kind,
 378                                                              int);
 379     struct exception_event_record *(*to_get_current_exception_event) (void);
 380     char *(*to_pid_to_exec_file) (int pid);
 381     enum strata to_stratum;
 382     int to_has_all_memory;
 383     int to_has_memory;
 384     int to_has_stack;
 385     int to_has_registers;
 386     int to_has_execution;
 387     int to_has_thread_control;  /* control thread execution */
 388     struct section_table
 389      *to_sections;
 390     struct section_table
 391      *to_sections_end;
 392     /* ASYNC target controls */
 393     int (*to_can_async_p) (void);
 394     int (*to_is_async_p) (void);
 395     void (*to_async) (void (*cb) (enum inferior_event_type, void *context),
 396                       void *context);
 397     int to_async_mask_value;
 398     int (*to_find_memory_regions) (int (*) (CORE_ADDR,
 399                                             unsigned long,
 400                                             int, int, int,
 401                                             void *),
 402                                    void *);
 403     char * (*to_make_corefile_notes) (bfd *, int *);
 404
 405     /* Return the thread-local address at OFFSET in the
 406        thread-local storage for the thread PTID and the shared library
 407        or executable file given by OBJFILE.  If that block of
 408        thread-local storage hasn't been allocated yet, this function
 409        may return an error.  */
 410     CORE_ADDR (*to_get_thread_local_address) (ptid_t ptid,
 411                                               struct objfile *objfile,
 412                                               CORE_ADDR offset);
 413
 414     /* Perform partial transfers on OBJECT.  See target_read_partial
 415        and target_write_partial for details of each variant.  One, and
 416        only one, of readbuf or writebuf must be non-NULL.  */
 417     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 418                                 enum target_object object, const char *annex,
 419                                 void *readbuf, const void *writebuf,
 420                                 ULONGEST offset, LONGEST len);
 421
 422     int to_magic;
 423     /* Need sub-structure for target machine related rather than comm related?
 424      */
 425   };
 426
 427 /* Magic number for checking ops size.  If a struct doesn't end with this
 428    number, somebody changed the declaration but didn't change all the
 429    places that initialize one.  */
 430
 431 #define OPS_MAGIC       3840
 432
 433 /* The ops structure for our "current" target process.  This should
 434    never be NULL.  If there is no target, it points to the dummy_target.  */
 435
 436 extern struct target_ops current_target;
 437
 438 /* Define easy words for doing these operations on our current target.  */
 439
 440 #define target_shortname        (current_target.to_shortname)
 441 #define target_longname         (current_target.to_longname)
 442
 443 /* Does whatever cleanup is required for a target that we are no
 444    longer going to be calling.  QUITTING indicates that GDB is exiting
 445    and should not get hung on an error (otherwise it is important to
 446    perform clean termination, even if it takes a while).  This routine
 447    is automatically always called when popping the target off the
 448    target stack (to_beneath is undefined).  Closing file descriptors
 449    and freeing all memory allocated memory are typical things it
 450    should do.  */
 451
 452 void target_close (struct target_ops *targ, int quitting);
 453
 454 /* Attaches to a process on the target side.  Arguments are as passed
 455    to the `attach' command by the user.  This routine can be called
 456    when the target is not on the target-stack, if the target_can_run
 457    routine returns 1; in that case, it must push itself onto the stack.
 458    Upon exit, the target should be ready for normal operations, and
 459    should be ready to deliver the status of the process immediately
 460    (without waiting) to an upcoming target_wait call.  */
 461
 462 #define target_attach(args, from_tty)   \
 463      (*current_target.to_attach) (args, from_tty)
 464
 465 /* The target_attach operation places a process under debugger control,
 466    and stops the process.
 467
 468    This operation provides a target-specific hook that allows the
 469    necessary bookkeeping to be performed after an attach completes.  */
 470 #define target_post_attach(pid) \
 471      (*current_target.to_post_attach) (pid)
 472
 473 /* Takes a program previously attached to and detaches it.
 474    The program may resume execution (some targets do, some don't) and will
 475    no longer stop on signals, etc.  We better not have left any breakpoints
 476    in the program or it'll die when it hits one.  ARGS is arguments
 477    typed by the user (e.g. a signal to send the process).  FROM_TTY
 478    says whether to be verbose or not.  */
 479
 480 extern void target_detach (char *, int);
 481
 482 /* Disconnect from the current target without resuming it (leaving it
 483    waiting for a debugger).  */
 484
 485 extern void target_disconnect (char *, int);
 486
 487 /* Resume execution of the target process PTID.  STEP says whether to
 488    single-step or to run free; SIGGNAL is the signal to be given to
 489    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 490    pass TARGET_SIGNAL_DEFAULT.  */
 491
 492 #define target_resume(ptid, step, siggnal)                              \
 493   do {                                                                  \
 494     dcache_invalidate(target_dcache);                                   \
 495     (*current_target.to_resume) (ptid, step, siggnal);                  \
 496   } while (0)
 497
 498 /* Wait for process pid to do something.  PTID = -1 to wait for any
 499    pid to do something.  Return pid of child, or -1 in case of error;
 500    store status through argument pointer STATUS.  Note that it is
 501    _NOT_ OK to throw_exception() out of target_wait() without popping
 502    the debugging target from the stack; GDB isn't prepared to get back
 503    to the prompt with a debugging target but without the frame cache,
 504    stop_pc, etc., set up.  */
 505
 506 #define target_wait(ptid, status)               \
 507      (*current_target.to_wait) (ptid, status)
 508
 509 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 510
 511 #define target_fetch_registers(regno)   \
 512      (*current_target.to_fetch_registers) (regno)
 513
 514 /* Store at least register REGNO, or all regs if REGNO == -1.
 515    It can store as many registers as it wants to, so target_prepare_to_store
 516    must have been previously called.  Calls error() if there are problems.  */
 517
 518 #define target_store_registers(regs)    \
 519      (*current_target.to_store_registers) (regs)
 520
 521 /* Get ready to modify the registers array.  On machines which store
 522    individual registers, this doesn't need to do anything.  On machines
 523    which store all the registers in one fell swoop, this makes sure
 524    that REGISTERS contains all the registers from the program being
 525    debugged.  */
 526
 527 #define target_prepare_to_store()       \
 528      (*current_target.to_prepare_to_store) ()
 529
 530 extern DCACHE *target_dcache;
 531
 532 extern int do_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
 533                            struct mem_attrib *attrib);
 534
 535 extern int target_read_string (CORE_ADDR, char **, int, int *);
 536
 537 extern int target_read_memory (CORE_ADDR memaddr, char *myaddr, int len);
 538
 539 extern int target_write_memory (CORE_ADDR memaddr, char *myaddr, int len);
 540
 541 extern int xfer_memory (CORE_ADDR, char *, int, int,
 542                         struct mem_attrib *, struct target_ops *);
 543
 544 extern int child_xfer_memory (CORE_ADDR, char *, int, int,
 545                               struct mem_attrib *, struct target_ops *);
 546
 547 /* Make a single attempt at transfering LEN bytes.  On a successful
 548    transfer, the number of bytes actually transfered is returned and
 549    ERR is set to 0.  When a transfer fails, -1 is returned (the number
 550    of bytes actually transfered is not defined) and ERR is set to a
 551    non-zero error indication.  */
 552
 553 extern int target_read_memory_partial (CORE_ADDR addr, char *buf, int len,
 554                                        int *err);
 555
 556 extern int target_write_memory_partial (CORE_ADDR addr, char *buf, int len,
 557                                         int *err);
 558
 559 extern char *child_pid_to_exec_file (int);
 560
 561 extern char *child_core_file_to_sym_file (char *);
 562
 563 #if defined(CHILD_POST_ATTACH)
 564 extern void child_post_attach (int);
 565 #endif
 566
 567 extern void child_post_startup_inferior (ptid_t);
 568
 569 extern void child_acknowledge_created_inferior (int);
 570
 571 extern int child_insert_fork_catchpoint (int);
 572
 573 extern int child_remove_fork_catchpoint (int);
 574
 575 extern int child_insert_vfork_catchpoint (int);
 576
 577 extern int child_remove_vfork_catchpoint (int);
 578
 579 extern void child_acknowledge_created_inferior (int);
 580
 581 extern int child_follow_fork (int);
 582
 583 extern int child_insert_exec_catchpoint (int);
 584
 585 extern int child_remove_exec_catchpoint (int);
 586
 587 extern int child_reported_exec_events_per_exec_call (void);
 588
 589 extern int child_has_exited (int, int, int *);
 590
 591 extern int child_thread_alive (ptid_t);
 592
 593 /* From infrun.c.  */
 594
 595 extern int inferior_has_forked (int pid, int *child_pid);
 596
 597 extern int inferior_has_vforked (int pid, int *child_pid);
 598
 599 extern int inferior_has_execd (int pid, char **execd_pathname);
 600
 601 /* From exec.c */
 602
 603 extern void print_section_info (struct target_ops *, bfd *);
 604
 605 /* Print a line about the current target.  */
 606
 607 #define target_files_info()     \
 608      (*current_target.to_files_info) (&current_target)
 609
 610 /* Insert a breakpoint at address ADDR in the target machine.  SAVE is
 611    a pointer to memory allocated for saving the target contents.  It
 612    is guaranteed by the caller to be long enough to save the number of
 613    breakpoint bytes indicated by BREAKPOINT_FROM_PC.  Result is 0 for
 614    success, or an errno value.  */
 615
 616 #define target_insert_breakpoint(addr, save)    \
 617      (*current_target.to_insert_breakpoint) (addr, save)
 618
 619 /* Remove a breakpoint at address ADDR in the target machine.
 620    SAVE is a pointer to the same save area
 621    that was previously passed to target_insert_breakpoint.
 622    Result is 0 for success, or an errno value.  */
 623
 624 #define target_remove_breakpoint(addr, save)    \
 625      (*current_target.to_remove_breakpoint) (addr, save)
 626
 627 /* Initialize the terminal settings we record for the inferior,
 628    before we actually run the inferior.  */
 629
 630 #define target_terminal_init() \
 631      (*current_target.to_terminal_init) ()
 632
 633 /* Put the inferior's terminal settings into effect.
 634    This is preparation for starting or resuming the inferior.  */
 635
 636 #define target_terminal_inferior() \
 637      (*current_target.to_terminal_inferior) ()
 638
 639 /* Put some of our terminal settings into effect,
 640    enough to get proper results from our output,
 641    but do not change into or out of RAW mode
 642    so that no input is discarded.
 643
 644    After doing this, either terminal_ours or terminal_inferior
 645    should be called to get back to a normal state of affairs.  */
 646
 647 #define target_terminal_ours_for_output() \
 648      (*current_target.to_terminal_ours_for_output) ()
 649
 650 /* Put our terminal settings into effect.
 651    First record the inferior's terminal settings
 652    so they can be restored properly later.  */
 653
 654 #define target_terminal_ours() \
 655      (*current_target.to_terminal_ours) ()
 656
 657 /* Save our terminal settings.
 658    This is called from TUI after entering or leaving the curses
 659    mode.  Since curses modifies our terminal this call is here
 660    to take this change into account.  */
 661
 662 #define target_terminal_save_ours() \
 663      (*current_target.to_terminal_save_ours) ()
 664
 665 /* Print useful information about our terminal status, if such a thing
 666    exists.  */
 667
 668 #define target_terminal_info(arg, from_tty) \
 669      (*current_target.to_terminal_info) (arg, from_tty)
 670
 671 /* Kill the inferior process.   Make it go away.  */
 672
 673 #define target_kill() \
 674      (*current_target.to_kill) ()
 675
 676 /* Load an executable file into the target process.  This is expected
 677    to not only bring new code into the target process, but also to
 678    update GDB's symbol tables to match.  */
 679
 680 extern void target_load (char *arg, int from_tty);
 681
 682 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 683    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 684    symbol should be returned.  The result is 0 if successful, nonzero
 685    if the symbol does not exist in the target environment.  This
 686    function should not call error() if communication with the target
 687    is interrupted, since it is called from symbol reading, but should
 688    return nonzero, possibly doing a complain().  */
 689
 690 #define target_lookup_symbol(name, addrp) \
 691      (*current_target.to_lookup_symbol) (name, addrp)
 692
 693 /* Start an inferior process and set inferior_ptid to its pid.
 694    EXEC_FILE is the file to run.
 695    ALLARGS is a string containing the arguments to the program.
 696    ENV is the environment vector to pass.  Errors reported with error().
 697    On VxWorks and various standalone systems, we ignore exec_file.  */
 698
 699 #define target_create_inferior(exec_file, args, env, FROM_TTY)  \
 700      (*current_target.to_create_inferior) (exec_file, args, env, (FROM_TTY))
 701
 702
 703 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 704    notification of inferior events such as fork and vork immediately
 705    after the inferior is created.  (This because of how gdb gets an
 706    inferior created via invoking a shell to do it.  In such a scenario,
 707    if the shell init file has commands in it, the shell will fork and
 708    exec for each of those commands, and we will see each such fork
 709    event.  Very bad.)
 710
 711    Such targets will supply an appropriate definition for this function.  */
 712
 713 #define target_post_startup_inferior(ptid) \
 714      (*current_target.to_post_startup_inferior) (ptid)
 715
 716 /* On some targets, the sequence of starting up an inferior requires
 717    some synchronization between gdb and the new inferior process, PID.  */
 718
 719 #define target_acknowledge_created_inferior(pid) \
 720      (*current_target.to_acknowledge_created_inferior) (pid)
 721
 722 /* On some targets, we can catch an inferior fork or vfork event when
 723    it occurs.  These functions insert/remove an already-created
 724    catchpoint for such events.  */
 725
 726 #define target_insert_fork_catchpoint(pid) \
 727      (*current_target.to_insert_fork_catchpoint) (pid)
 728
 729 #define target_remove_fork_catchpoint(pid) \
 730      (*current_target.to_remove_fork_catchpoint) (pid)
 731
 732 #define target_insert_vfork_catchpoint(pid) \
 733      (*current_target.to_insert_vfork_catchpoint) (pid)
 734
 735 #define target_remove_vfork_catchpoint(pid) \
 736      (*current_target.to_remove_vfork_catchpoint) (pid)
 737
 738 /* If the inferior forks or vforks, this function will be called at
 739    the next resume in order to perform any bookkeeping and fiddling
 740    necessary to continue debugging either the parent or child, as
 741    requested, and releasing the other.  Information about the fork
 742    or vfork event is available via get_last_target_status ().
 743    This function returns 1 if the inferior should not be resumed
 744    (i.e. there is another event pending).  */
 745
 746 #define target_follow_fork(follow_child) \
 747      (*current_target.to_follow_fork) (follow_child)
 748
 749 /* On some targets, we can catch an inferior exec event when it
 750    occurs.  These functions insert/remove an already-created
 751    catchpoint for such events.  */
 752
 753 #define target_insert_exec_catchpoint(pid) \
 754      (*current_target.to_insert_exec_catchpoint) (pid)
 755
 756 #define target_remove_exec_catchpoint(pid) \
 757      (*current_target.to_remove_exec_catchpoint) (pid)
 758
 759 /* Returns the number of exec events that are reported when a process
 760    invokes a flavor of the exec() system call on this target, if exec
 761    events are being reported.  */
 762
 763 #define target_reported_exec_events_per_exec_call() \
 764      (*current_target.to_reported_exec_events_per_exec_call) ()
 765
 766 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 767    exit code of PID, if any.  */
 768
 769 #define target_has_exited(pid,wait_status,exit_status) \
 770      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 771
 772 /* The debugger has completed a blocking wait() call.  There is now
 773    some process event that must be processed.  This function should
 774    be defined by those targets that require the debugger to perform
 775    cleanup or internal state changes in response to the process event.  */
 776
 777 /* The inferior process has died.  Do what is right.  */
 778
 779 #define target_mourn_inferior() \
 780      (*current_target.to_mourn_inferior) ()
 781
 782 /* Does target have enough data to do a run or attach command? */
 783
 784 #define target_can_run(t) \
 785      ((t)->to_can_run) ()
 786
 787 /* post process changes to signal handling in the inferior.  */
 788
 789 #define target_notice_signals(ptid) \
 790      (*current_target.to_notice_signals) (ptid)
 791
 792 /* Check to see if a thread is still alive.  */
 793
 794 #define target_thread_alive(ptid) \
 795      (*current_target.to_thread_alive) (ptid)
 796
 797 /* Query for new threads and add them to the thread list.  */
 798
 799 #define target_find_new_threads() \
 800      (*current_target.to_find_new_threads) (); \
 801
 802 /* Make target stop in a continuable fashion.  (For instance, under
 803    Unix, this should act like SIGSTOP).  This function is normally
 804    used by GUIs to implement a stop button.  */
 805
 806 #define target_stop current_target.to_stop
 807
 808 /* Send the specified COMMAND to the target's monitor
 809    (shell,interpreter) for execution.  The result of the query is
 810    placed in OUTBUF.  */
 811
 812 #define target_rcmd(command, outbuf) \
 813      (*current_target.to_rcmd) (command, outbuf)
 814
 815
 816 /* Get the symbol information for a breakpointable routine called when
 817    an exception event occurs.
 818    Intended mainly for C++, and for those
 819    platforms/implementations where such a callback mechanism is available,
 820    e.g. HP-UX with ANSI C++ (aCC).  Some compilers (e.g. g++) support
 821    different mechanisms for debugging exceptions.  */
 822
 823 #define target_enable_exception_callback(kind, enable) \
 824      (*current_target.to_enable_exception_callback) (kind, enable)
 825
 826 /* Get the current exception event kind -- throw or catch, etc.  */
 827
 828 #define target_get_current_exception_event() \
 829      (*current_target.to_get_current_exception_event) ()
 830
 831 /* Does the target include all of memory, or only part of it?  This
 832    determines whether we look up the target chain for other parts of
 833    memory if this target can't satisfy a request.  */
 834
 835 #define target_has_all_memory   \
 836      (current_target.to_has_all_memory)
 837
 838 /* Does the target include memory?  (Dummy targets don't.)  */
 839
 840 #define target_has_memory       \
 841      (current_target.to_has_memory)
 842
 843 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 844    we start a process.)  */
 845
 846 #define target_has_stack        \
 847      (current_target.to_has_stack)
 848
 849 /* Does the target have registers?  (Exec files don't.)  */
 850
 851 #define target_has_registers    \
 852      (current_target.to_has_registers)
 853
 854 /* Does the target have execution?  Can we make it jump (through
 855    hoops), or pop its stack a few times?  FIXME: If this is to work that
 856    way, it needs to check whether an inferior actually exists.
 857    remote-udi.c and probably other targets can be the current target
 858    when the inferior doesn't actually exist at the moment.  Right now
 859    this just tells us whether this target is *capable* of execution.  */
 860
 861 #define target_has_execution    \
 862      (current_target.to_has_execution)
 863
 864 /* Can the target support the debugger control of thread execution?
 865    a) Can it lock the thread scheduler?
 866    b) Can it switch the currently running thread?  */
 867
 868 #define target_can_lock_scheduler \
 869      (current_target.to_has_thread_control & tc_schedlock)
 870
 871 #define target_can_switch_threads \
 872      (current_target.to_has_thread_control & tc_switch)
 873
 874 /* Can the target support asynchronous execution? */
 875 #define target_can_async_p() (current_target.to_can_async_p ())
 876
 877 /* Is the target in asynchronous execution mode? */
 878 #define target_is_async_p() (current_target.to_is_async_p())
 879
 880 /* Put the target in async mode with the specified callback function. */
 881 #define target_async(CALLBACK,CONTEXT) \
 882      (current_target.to_async((CALLBACK), (CONTEXT)))
 883
 884 /* This is to be used ONLY within call_function_by_hand(). It provides
 885    a workaround, to have inferior function calls done in sychronous
 886    mode, even though the target is asynchronous. After
 887    target_async_mask(0) is called, calls to target_can_async_p() will
 888    return FALSE , so that target_resume() will not try to start the
 889    target asynchronously. After the inferior stops, we IMMEDIATELY
 890    restore the previous nature of the target, by calling
 891    target_async_mask(1). After that, target_can_async_p() will return
 892    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
 893
 894    FIXME ezannoni 1999-12-13: we won't need this once we move
 895    the turning async on and off to the single execution commands,
 896    from where it is done currently, in remote_resume().  */
 897
 898 #define target_async_mask_value \
 899      (current_target.to_async_mask_value)
 900
 901 extern int target_async_mask (int mask);
 902
 903 extern void target_link (char *, CORE_ADDR *);
 904
 905 /* Converts a process id to a string.  Usually, the string just contains
 906    `process xyz', but on some systems it may contain
 907    `process xyz thread abc'.  */
 908
 909 #undef target_pid_to_str
 910 #define target_pid_to_str(PID) current_target.to_pid_to_str (PID)
 911
 912 #ifndef target_tid_to_str
 913 #define target_tid_to_str(PID) \
 914      target_pid_to_str (PID)
 915 extern char *normal_pid_to_str (ptid_t ptid);
 916 #endif
 917
 918 /* Return a short string describing extra information about PID,
 919    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
 920    is okay.  */
 921
 922 #define target_extra_thread_info(TP) \
 923      (current_target.to_extra_thread_info (TP))
 924
 925 /*
 926  * New Objfile Event Hook:
 927  *
 928  * Sometimes a GDB component wants to get notified whenever a new
 929  * objfile is loaded.  Mainly this is used by thread-debugging
 930  * implementations that need to know when symbols for the target
 931  * thread implemenation are available.
 932  *
 933  * The old way of doing this is to define a macro 'target_new_objfile'
 934  * that points to the function that you want to be called on every
 935  * objfile/shlib load.
 936
 937    The new way is to grab the function pointer,
 938    'deprecated_target_new_objfile_hook', and point it to the function
 939    that you want to be called on every objfile/shlib load.
 940
 941    If multiple clients are willing to be cooperative, they can each
 942    save a pointer to the previous value of
 943    deprecated_target_new_objfile_hook before modifying it, and arrange
 944    for their function to call the previous function in the chain.  In
 945    that way, multiple clients can receive this notification (something
 946    like with signal handlers).  */
 947
 948 extern void (*deprecated_target_new_objfile_hook) (struct objfile *);
 949
 950 #ifndef target_pid_or_tid_to_str
 951 #define target_pid_or_tid_to_str(ID) \
 952      target_pid_to_str (ID)
 953 #endif
 954
 955 /* Attempts to find the pathname of the executable file
 956    that was run to create a specified process.
 957
 958    The process PID must be stopped when this operation is used.
 959
 960    If the executable file cannot be determined, NULL is returned.
 961
 962    Else, a pointer to a character string containing the pathname
 963    is returned.  This string should be copied into a buffer by
 964    the client if the string will not be immediately used, or if
 965    it must persist.  */
 966
 967 #define target_pid_to_exec_file(pid) \
 968      (current_target.to_pid_to_exec_file) (pid)
 969
 970 /*
 971  * Iterator function for target memory regions.
 972  * Calls a callback function once for each memory region 'mapped'
 973  * in the child process.  Defined as a simple macro rather than
 974  * as a function macro so that it can be tested for nullity.
 975  */
 976
 977 #define target_find_memory_regions(FUNC, DATA) \
 978      (current_target.to_find_memory_regions) (FUNC, DATA)
 979
 980 /*
 981  * Compose corefile .note section.
 982  */
 983
 984 #define target_make_corefile_notes(BFD, SIZE_P) \
 985      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
 986
 987 /* Thread-local values.  */
 988 #define target_get_thread_local_address \
 989     (current_target.to_get_thread_local_address)
 990 #define target_get_thread_local_address_p() \
 991     (target_get_thread_local_address != NULL)
 992
 993 /* Hook to call target dependent code just after inferior target process has
 994    started.  */
 995
 996 #ifndef TARGET_CREATE_INFERIOR_HOOK
 997 #define TARGET_CREATE_INFERIOR_HOOK(PID)
 998 #endif
 999
1000 /* Hardware watchpoint interfaces.  */
1001
1002 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1003    write).  */
1004
1005 #ifndef STOPPED_BY_WATCHPOINT
1006 #define STOPPED_BY_WATCHPOINT(w) \
1007    (*current_target.to_stopped_by_watchpoint) ()
1008 #endif
1009
1010 /* Non-zero if we have continuable watchpoints  */
1011
1012 #ifndef HAVE_CONTINUABLE_WATCHPOINT
1013 #define HAVE_CONTINUABLE_WATCHPOINT \
1014    (current_target.to_have_continuable_watchpoint)
1015 #endif
1016
1017 /* HP-UX supplies these operations, which respectively disable and enable
1018    the memory page-protections that are used to implement hardware watchpoints
1019    on that platform.  See wait_for_inferior's use of these.  */
1020
1021 #if !defined(TARGET_DISABLE_HW_WATCHPOINTS)
1022 #define TARGET_DISABLE_HW_WATCHPOINTS(pid)
1023 #endif
1024
1025 #if !defined(TARGET_ENABLE_HW_WATCHPOINTS)
1026 #define TARGET_ENABLE_HW_WATCHPOINTS(pid)
1027 #endif
1028
1029 /* Provide defaults for hardware watchpoint functions.  */
1030
1031 /* If the *_hw_beakpoint functions have not been defined
1032    elsewhere use the definitions in the target vector.  */
1033
1034 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1035    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1036    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1037    (including this one?).  OTHERTYPE is who knows what...  */
1038
1039 #ifndef TARGET_CAN_USE_HARDWARE_WATCHPOINT
1040 #define TARGET_CAN_USE_HARDWARE_WATCHPOINT(TYPE,CNT,OTHERTYPE) \
1041  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1042 #endif
1043
1044 #if !defined(TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT)
1045 #define TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT(byte_count) \
1046     (*current_target.to_region_size_ok_for_hw_watchpoint) (byte_count)
1047 #endif
1048
1049
1050 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1051    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1052    success, non-zero for failure.  */
1053
1054 #ifndef target_insert_watchpoint
1055 #define target_insert_watchpoint(addr, len, type)       \
1056      (*current_target.to_insert_watchpoint) (addr, len, type)
1057
1058 #define target_remove_watchpoint(addr, len, type)       \
1059      (*current_target.to_remove_watchpoint) (addr, len, type)
1060 #endif
1061
1062 #ifndef target_insert_hw_breakpoint
1063 #define target_insert_hw_breakpoint(addr, save) \
1064      (*current_target.to_insert_hw_breakpoint) (addr, save)
1065
1066 #define target_remove_hw_breakpoint(addr, save) \
1067      (*current_target.to_remove_hw_breakpoint) (addr, save)
1068 #endif
1069
1070 #ifndef target_stopped_data_address
1071 #define target_stopped_data_address() \
1072     (*current_target.to_stopped_data_address) ()
1073 #endif
1074
1075 /* This will only be defined by a target that supports catching vfork events,
1076    such as HP-UX.
1077
1078    On some targets (such as HP-UX 10.20 and earlier), resuming a newly vforked
1079    child process after it has exec'd, causes the parent process to resume as
1080    well.  To prevent the parent from running spontaneously, such targets should
1081    define this to a function that prevents that from happening.  */
1082 #if !defined(ENSURE_VFORKING_PARENT_REMAINS_STOPPED)
1083 #define ENSURE_VFORKING_PARENT_REMAINS_STOPPED(PID) (0)
1084 #endif
1085
1086 /* This will only be defined by a target that supports catching vfork events,
1087    such as HP-UX.
1088
1089    On some targets (such as HP-UX 10.20 and earlier), a newly vforked child
1090    process must be resumed when it delivers its exec event, before the parent
1091    vfork event will be delivered to us.  */
1092
1093 #if !defined(RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK)
1094 #define RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK() (0)
1095 #endif
1096
1097 /* Routines for maintenance of the target structures...
1098
1099    add_target:   Add a target to the list of all possible targets.
1100
1101    push_target:  Make this target the top of the stack of currently used
1102    targets, within its particular stratum of the stack.  Result
1103    is 0 if now atop the stack, nonzero if not on top (maybe
1104    should warn user).
1105
1106    unpush_target: Remove this from the stack of currently used targets,
1107    no matter where it is on the list.  Returns 0 if no
1108    change, 1 if removed from stack.
1109
1110    pop_target:   Remove the top thing on the stack of current targets.  */
1111
1112 extern void add_target (struct target_ops *);
1113
1114 extern int push_target (struct target_ops *);
1115
1116 extern int unpush_target (struct target_ops *);
1117
1118 extern void target_preopen (int);
1119
1120 extern void pop_target (void);
1121
1122 /* Struct section_table maps address ranges to file sections.  It is
1123    mostly used with BFD files, but can be used without (e.g. for handling
1124    raw disks, or files not in formats handled by BFD).  */
1125
1126 struct section_table
1127   {
1128     CORE_ADDR addr;             /* Lowest address in section */
1129     CORE_ADDR endaddr;          /* 1+highest address in section */
1130
1131     struct bfd_section *the_bfd_section;
1132
1133     bfd *bfd;                   /* BFD file pointer */
1134   };
1135
1136 /* Return the "section" containing the specified address.  */
1137 struct section_table *target_section_by_addr (struct target_ops *target,
1138                                               CORE_ADDR addr);
1139
1140
1141 /* From mem-break.c */
1142
1143 extern int memory_remove_breakpoint (CORE_ADDR, char *);
1144
1145 extern int memory_insert_breakpoint (CORE_ADDR, char *);
1146
1147 extern int default_memory_remove_breakpoint (CORE_ADDR, char *);
1148
1149 extern int default_memory_insert_breakpoint (CORE_ADDR, char *);
1150
1151
1152 /* From target.c */
1153
1154 extern void initialize_targets (void);
1155
1156 extern void noprocess (void);
1157
1158 extern void find_default_attach (char *, int);
1159
1160 extern void find_default_create_inferior (char *, char *, char **, int);
1161
1162 extern struct target_ops *find_run_target (void);
1163
1164 extern struct target_ops *find_core_target (void);
1165
1166 extern struct target_ops *find_target_beneath (struct target_ops *);
1167
1168 extern int target_resize_to_sections (struct target_ops *target,
1169                                       int num_added);
1170
1171 extern void remove_target_sections (bfd *abfd);
1172
1173 \f
1174 /* Stuff that should be shared among the various remote targets.  */
1175
1176 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1177    information (higher values, more information).  */
1178 extern int remote_debug;
1179
1180 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1181 extern int baud_rate;
1182 /* Timeout limit for response from target. */
1183 extern int remote_timeout;
1184
1185 \f
1186 /* Functions for helping to write a native target.  */
1187
1188 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1189 extern void store_waitstatus (struct target_waitstatus *, int);
1190
1191 /* Predicate to target_signal_to_host(). Return non-zero if the enum
1192    targ_signal SIGNO has an equivalent ``host'' representation.  */
1193 /* FIXME: cagney/1999-11-22: The name below was chosen in preference
1194    to the shorter target_signal_p() because it is far less ambigious.
1195    In this context ``target_signal'' refers to GDB's internal
1196    representation of the target's set of signals while ``host signal''
1197    refers to the target operating system's signal.  Confused?  */
1198
1199 extern int target_signal_to_host_p (enum target_signal signo);
1200
1201 /* Convert between host signal numbers and enum target_signal's.
1202    target_signal_to_host() returns 0 and prints a warning() on GDB's
1203    console if SIGNO has no equivalent host representation.  */
1204 /* FIXME: cagney/1999-11-22: Here ``host'' is used incorrectly, it is
1205    refering to the target operating system's signal numbering.
1206    Similarly, ``enum target_signal'' is named incorrectly, ``enum
1207    gdb_signal'' would probably be better as it is refering to GDB's
1208    internal representation of a target operating system's signal.  */
1209
1210 extern enum target_signal target_signal_from_host (int);
1211 extern int target_signal_to_host (enum target_signal);
1212
1213 /* Convert from a number used in a GDB command to an enum target_signal.  */
1214 extern enum target_signal target_signal_from_command (int);
1215
1216 /* Any target can call this to switch to remote protocol (in remote.c). */
1217 extern void push_remote_target (char *name, int from_tty);
1218 \f
1219 /* Imported from machine dependent code */
1220
1221 /* Blank target vector entries are initialized to target_ignore. */
1222 void target_ignore (void);
1223
1224 extern struct target_ops child_ops;
1225
1226 #endif /* !defined (TARGET_H) */