gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2    Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   3    2000, 2001, 2002 Free Software Foundation, Inc.
   4    Contributed by Cygnus Support.  Written by John Gilmore.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #if !defined (TARGET_H)
  24 #define TARGET_H
  25
  26 /* This include file defines the interface between the main part
  27    of the debugger, and the part which is target-specific, or
  28    specific to the communications interface between us and the
  29    target.
  30
  31    A TARGET is an interface between the debugger and a particular
  32    kind of file or process.  Targets can be STACKED in STRATA,
  33    so that more than one target can potentially respond to a request.
  34    In particular, memory accesses will walk down the stack of targets
  35    until they find a target that is interested in handling that particular
  36    address.  STRATA are artificial boundaries on the stack, within
  37    which particular kinds of targets live.  Strata exist so that
  38    people don't get confused by pushing e.g. a process target and then
  39    a file target, and wondering why they can't see the current values
  40    of variables any more (the file target is handling them and they
  41    never get to the process target).  So when you push a file target,
  42    it goes into the file stratum, which is always below the process
  43    stratum.  */
  44
  45 #include "bfd.h"
  46 #include "symtab.h"
  47 #include "dcache.h"
  48 #include "memattr.h"
  49
  50 enum strata
  51   {
  52     dummy_stratum,              /* The lowest of the low */
  53     file_stratum,               /* Executable files, etc */
  54     core_stratum,               /* Core dump files */
  55     download_stratum,           /* Downloading of remote targets */
  56     process_stratum,            /* Executing processes */
  57     thread_stratum              /* Executing threads */
  58   };
  59
  60 enum thread_control_capabilities
  61   {
  62     tc_none = 0,                /* Default: can't control thread execution.  */
  63     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  64     tc_switch = 2               /* Can switch the running thread on demand.  */
  65   };
  66
  67 /* Stuff for target_wait.  */
  68
  69 /* Generally, what has the program done?  */
  70 enum target_waitkind
  71   {
  72     /* The program has exited.  The exit status is in value.integer.  */
  73     TARGET_WAITKIND_EXITED,
  74
  75     /* The program has stopped with a signal.  Which signal is in
  76        value.sig.  */
  77     TARGET_WAITKIND_STOPPED,
  78
  79     /* The program has terminated with a signal.  Which signal is in
  80        value.sig.  */
  81     TARGET_WAITKIND_SIGNALLED,
  82
  83     /* The program is letting us know that it dynamically loaded something
  84        (e.g. it called load(2) on AIX).  */
  85     TARGET_WAITKIND_LOADED,
  86
  87     /* The program has forked.  A "related" process' ID is in
  88        value.related_pid.  I.e., if the child forks, value.related_pid
  89        is the parent's ID.  */
  90
  91     TARGET_WAITKIND_FORKED,
  92
  93     /* The program has vforked.  A "related" process's ID is in
  94        value.related_pid.  */
  95
  96     TARGET_WAITKIND_VFORKED,
  97
  98     /* The program has exec'ed a new executable file.  The new file's
  99        pathname is pointed to by value.execd_pathname.  */
 100
 101     TARGET_WAITKIND_EXECD,
 102
 103     /* The program has entered or returned from a system call.  On
 104        HP-UX, this is used in the hardware watchpoint implementation.
 105        The syscall's unique integer ID number is in value.syscall_id */
 106
 107     TARGET_WAITKIND_SYSCALL_ENTRY,
 108     TARGET_WAITKIND_SYSCALL_RETURN,
 109
 110     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 111        within target_wait, but I'm not sure target_wait should be resuming the
 112        inferior.  */
 113     TARGET_WAITKIND_SPURIOUS,
 114
 115     /* An event has occured, but we should wait again.
 116        Remote_async_wait() returns this when there is an event
 117        on the inferior, but the rest of the world is not interested in
 118        it. The inferior has not stopped, but has just sent some output
 119        to the console, for instance. In this case, we want to go back
 120        to the event loop and wait there for another event from the
 121        inferior, rather than being stuck in the remote_async_wait()
 122        function. This way the event loop is responsive to other events,
 123        like for instance the user typing.  */
 124     TARGET_WAITKIND_IGNORE
 125   };
 126
 127 struct target_waitstatus
 128   {
 129     enum target_waitkind kind;
 130
 131     /* Forked child pid, execd pathname, exit status or signal number.  */
 132     union
 133       {
 134         int integer;
 135         enum target_signal sig;
 136         int related_pid;
 137         char *execd_pathname;
 138         int syscall_id;
 139       }
 140     value;
 141   };
 142
 143 /* Possible types of events that the inferior handler will have to
 144    deal with.  */
 145 enum inferior_event_type
 146   {
 147     /* There is a request to quit the inferior, abandon it.  */
 148     INF_QUIT_REQ,
 149     /* Process a normal inferior event which will result in target_wait
 150        being called.  */
 151     INF_REG_EVENT,
 152     /* Deal with an error on the inferior.  */
 153     INF_ERROR,
 154     /* We are called because a timer went off.  */
 155     INF_TIMER,
 156     /* We are called to do stuff after the inferior stops.  */
 157     INF_EXEC_COMPLETE,
 158     /* We are called to do some stuff after the inferior stops, but we
 159        are expected to reenter the proceed() and
 160        handle_inferior_event() functions. This is used only in case of
 161        'step n' like commands.  */
 162     INF_EXEC_CONTINUE
 163   };
 164
 165 /* Return the string for a signal.  */
 166 extern char *target_signal_to_string (enum target_signal);
 167
 168 /* Return the name (SIGHUP, etc.) for a signal.  */
 169 extern char *target_signal_to_name (enum target_signal);
 170
 171 /* Given a name (SIGHUP, etc.), return its signal.  */
 172 enum target_signal target_signal_from_name (char *);
 173 \f
 174
 175 /* If certain kinds of activity happen, target_wait should perform
 176    callbacks.  */
 177 /* Right now we just call (*TARGET_ACTIVITY_FUNCTION) if I/O is possible
 178    on TARGET_ACTIVITY_FD.  */
 179 extern int target_activity_fd;
 180 /* Returns zero to leave the inferior alone, one to interrupt it.  */
 181 extern int (*target_activity_function) (void);
 182 \f
 183 struct thread_info;             /* fwd decl for parameter list below: */
 184
 185 struct target_ops
 186   {
 187     char *to_shortname;         /* Name this target type */
 188     char *to_longname;          /* Name for printing */
 189     char *to_doc;               /* Documentation.  Does not include trailing
 190                                    newline, and starts with a one-line descrip-
 191                                    tion (probably similar to to_longname).  */
 192     void (*to_open) (char *, int);
 193     void (*to_close) (int);
 194     void (*to_attach) (char *, int);
 195     void (*to_post_attach) (int);
 196     void (*to_detach) (char *, int);
 197     void (*to_resume) (ptid_t, int, enum target_signal);
 198     ptid_t (*to_wait) (ptid_t, struct target_waitstatus *);
 199     void (*to_post_wait) (ptid_t, int);
 200     void (*to_fetch_registers) (int);
 201     void (*to_store_registers) (int);
 202     void (*to_prepare_to_store) (void);
 203
 204     /* Transfer LEN bytes of memory between GDB address MYADDR and
 205        target address MEMADDR.  If WRITE, transfer them to the target, else
 206        transfer them from the target.  TARGET is the target from which we
 207        get this function.
 208
 209        Return value, N, is one of the following:
 210
 211        0 means that we can't handle this.  If errno has been set, it is the
 212        error which prevented us from doing it (FIXME: What about bfd_error?).
 213
 214        positive (call it N) means that we have transferred N bytes
 215        starting at MEMADDR.  We might be able to handle more bytes
 216        beyond this length, but no promises.
 217
 218        negative (call its absolute value N) means that we cannot
 219        transfer right at MEMADDR, but we could transfer at least
 220        something at MEMADDR + N.  */
 221
 222     int (*to_xfer_memory) (CORE_ADDR memaddr, char *myaddr,
 223                            int len, int write,
 224                            struct mem_attrib *attrib,
 225                            struct target_ops *target);
 226
 227 #if 0
 228     /* Enable this after 4.12.  */
 229
 230     /* Search target memory.  Start at STARTADDR and take LEN bytes of
 231        target memory, and them with MASK, and compare to DATA.  If they
 232        match, set *ADDR_FOUND to the address we found it at, store the data
 233        we found at LEN bytes starting at DATA_FOUND, and return.  If
 234        not, add INCREMENT to the search address and keep trying until
 235        the search address is outside of the range [LORANGE,HIRANGE).
 236
 237        If we don't find anything, set *ADDR_FOUND to (CORE_ADDR)0 and
 238        return.  */
 239
 240     void (*to_search) (int len, char *data, char *mask,
 241                        CORE_ADDR startaddr, int increment,
 242                        CORE_ADDR lorange, CORE_ADDR hirange,
 243                        CORE_ADDR * addr_found, char *data_found);
 244
 245 #define target_search(len, data, mask, startaddr, increment, lorange, hirange, addr_found, data_found)  \
 246     (*current_target.to_search) (len, data, mask, startaddr, increment, \
 247                                  lorange, hirange, addr_found, data_found)
 248 #endif                          /* 0 */
 249
 250     void (*to_files_info) (struct target_ops *);
 251     int (*to_insert_breakpoint) (CORE_ADDR, char *);
 252     int (*to_remove_breakpoint) (CORE_ADDR, char *);
 253     int (*to_can_use_hw_breakpoint) (int, int, int);
 254     int (*to_insert_hw_breakpoint) (CORE_ADDR, char *);
 255     int (*to_remove_hw_breakpoint) (CORE_ADDR, char *);
 256     int (*to_remove_watchpoint) (CORE_ADDR, int, int);
 257     int (*to_insert_watchpoint) (CORE_ADDR, int, int);
 258     int (*to_stopped_by_watchpoint) (void);
 259     CORE_ADDR (*to_stopped_data_address) (void);
 260     int (*to_region_size_ok_for_hw_watchpoint) (int);
 261     void (*to_terminal_init) (void);
 262     void (*to_terminal_inferior) (void);
 263     void (*to_terminal_ours_for_output) (void);
 264     void (*to_terminal_ours) (void);
 265     void (*to_terminal_save_ours) (void);
 266     void (*to_terminal_info) (char *, int);
 267     void (*to_kill) (void);
 268     void (*to_load) (char *, int);
 269     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 270     void (*to_create_inferior) (char *, char *, char **);
 271     void (*to_post_startup_inferior) (ptid_t);
 272     void (*to_acknowledge_created_inferior) (int);
 273     int (*to_insert_fork_catchpoint) (int);
 274     int (*to_remove_fork_catchpoint) (int);
 275     int (*to_insert_vfork_catchpoint) (int);
 276     int (*to_remove_vfork_catchpoint) (int);
 277     int (*to_follow_fork) (int);
 278     int (*to_insert_exec_catchpoint) (int);
 279     int (*to_remove_exec_catchpoint) (int);
 280     int (*to_reported_exec_events_per_exec_call) (void);
 281     int (*to_has_exited) (int, int, int *);
 282     void (*to_mourn_inferior) (void);
 283     int (*to_can_run) (void);
 284     void (*to_notice_signals) (ptid_t ptid);
 285     int (*to_thread_alive) (ptid_t ptid);
 286     void (*to_find_new_threads) (void);
 287     char *(*to_pid_to_str) (ptid_t);
 288     char *(*to_extra_thread_info) (struct thread_info *);
 289     void (*to_stop) (void);
 290     int (*to_query) (int /*char */ , char *, char *, int *);
 291     void (*to_rcmd) (char *command, struct ui_file *output);
 292     struct symtab_and_line *(*to_enable_exception_callback) (enum
 293                                                              exception_event_kind,
 294                                                              int);
 295     struct exception_event_record *(*to_get_current_exception_event) (void);
 296     char *(*to_pid_to_exec_file) (int pid);
 297     enum strata to_stratum;
 298     struct target_ops
 299      *DONT_USE;                 /* formerly to_next */
 300     int to_has_all_memory;
 301     int to_has_memory;
 302     int to_has_stack;
 303     int to_has_registers;
 304     int to_has_execution;
 305     int to_has_thread_control;  /* control thread execution */
 306     struct section_table
 307      *to_sections;
 308     struct section_table
 309      *to_sections_end;
 310     /* ASYNC target controls */
 311     int (*to_can_async_p) (void);
 312     int (*to_is_async_p) (void);
 313     void (*to_async) (void (*cb) (enum inferior_event_type, void *context),
 314                       void *context);
 315     int to_async_mask_value;
 316     int (*to_find_memory_regions) (int (*) (CORE_ADDR,
 317                                             unsigned long,
 318                                             int, int, int,
 319                                             void *),
 320                                    void *);
 321     char * (*to_make_corefile_notes) (bfd *, int *);
 322
 323     /* Return the thread-local address at OFFSET in the
 324        thread-local storage for the thread PTID and the shared library
 325        or executable file given by OBJFILE.  If that block of
 326        thread-local storage hasn't been allocated yet, this function
 327        may return an error.  */
 328     CORE_ADDR (*to_get_thread_local_address) (ptid_t ptid,
 329                                               struct objfile *objfile,
 330                                               CORE_ADDR offset);
 331
 332     int to_magic;
 333     /* Need sub-structure for target machine related rather than comm related?
 334      */
 335   };
 336
 337 /* Magic number for checking ops size.  If a struct doesn't end with this
 338    number, somebody changed the declaration but didn't change all the
 339    places that initialize one.  */
 340
 341 #define OPS_MAGIC       3840
 342
 343 /* The ops structure for our "current" target process.  This should
 344    never be NULL.  If there is no target, it points to the dummy_target.  */
 345
 346 extern struct target_ops current_target;
 347
 348 /* An item on the target stack.  */
 349
 350 struct target_stack_item
 351   {
 352     struct target_stack_item *next;
 353     struct target_ops *target_ops;
 354   };
 355
 356 /* The target stack.  */
 357
 358 extern struct target_stack_item *target_stack;
 359
 360 /* Define easy words for doing these operations on our current target.  */
 361
 362 #define target_shortname        (current_target.to_shortname)
 363 #define target_longname         (current_target.to_longname)
 364
 365 /* The open routine takes the rest of the parameters from the command,
 366    and (if successful) pushes a new target onto the stack.
 367    Targets should supply this routine, if only to provide an error message.  */
 368
 369 #define target_open(name, from_tty)                                     \
 370   do {                                                                  \
 371     dcache_invalidate (target_dcache);                                  \
 372     (*current_target.to_open) (name, from_tty);                         \
 373   } while (0)
 374
 375 /* Does whatever cleanup is required for a target that we are no longer
 376    going to be calling.  Argument says whether we are quitting gdb and
 377    should not get hung in case of errors, or whether we want a clean
 378    termination even if it takes a while.  This routine is automatically
 379    always called just before a routine is popped off the target stack.
 380    Closing file descriptors and freeing memory are typical things it should
 381    do.  */
 382
 383 #define target_close(quitting)  \
 384      (*current_target.to_close) (quitting)
 385
 386 /* Attaches to a process on the target side.  Arguments are as passed
 387    to the `attach' command by the user.  This routine can be called
 388    when the target is not on the target-stack, if the target_can_run
 389    routine returns 1; in that case, it must push itself onto the stack.
 390    Upon exit, the target should be ready for normal operations, and
 391    should be ready to deliver the status of the process immediately
 392    (without waiting) to an upcoming target_wait call.  */
 393
 394 #define target_attach(args, from_tty)   \
 395      (*current_target.to_attach) (args, from_tty)
 396
 397 /* The target_attach operation places a process under debugger control,
 398    and stops the process.
 399
 400    This operation provides a target-specific hook that allows the
 401    necessary bookkeeping to be performed after an attach completes.  */
 402 #define target_post_attach(pid) \
 403      (*current_target.to_post_attach) (pid)
 404
 405 /* Takes a program previously attached to and detaches it.
 406    The program may resume execution (some targets do, some don't) and will
 407    no longer stop on signals, etc.  We better not have left any breakpoints
 408    in the program or it'll die when it hits one.  ARGS is arguments
 409    typed by the user (e.g. a signal to send the process).  FROM_TTY
 410    says whether to be verbose or not.  */
 411
 412 extern void target_detach (char *, int);
 413
 414 /* Resume execution of the target process PTID.  STEP says whether to
 415    single-step or to run free; SIGGNAL is the signal to be given to
 416    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 417    pass TARGET_SIGNAL_DEFAULT.  */
 418
 419 #define target_resume(ptid, step, siggnal)                              \
 420   do {                                                                  \
 421     dcache_invalidate(target_dcache);                                   \
 422     (*current_target.to_resume) (ptid, step, siggnal);                  \
 423   } while (0)
 424
 425 /* Wait for process pid to do something.  PTID = -1 to wait for any
 426    pid to do something.  Return pid of child, or -1 in case of error;
 427    store status through argument pointer STATUS.  Note that it is
 428    _NOT_ OK to throw_exception() out of target_wait() without popping
 429    the debugging target from the stack; GDB isn't prepared to get back
 430    to the prompt with a debugging target but without the frame cache,
 431    stop_pc, etc., set up.  */
 432
 433 #define target_wait(ptid, status)               \
 434      (*current_target.to_wait) (ptid, status)
 435
 436 /* The target_wait operation waits for a process event to occur, and
 437    thereby stop the process.
 438
 439    On some targets, certain events may happen in sequences.  gdb's
 440    correct response to any single event of such a sequence may require
 441    knowledge of what earlier events in the sequence have been seen.
 442
 443    This operation provides a target-specific hook that allows the
 444    necessary bookkeeping to be performed to track such sequences.  */
 445
 446 #define target_post_wait(ptid, status) \
 447      (*current_target.to_post_wait) (ptid, status)
 448
 449 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 450
 451 #define target_fetch_registers(regno)   \
 452      (*current_target.to_fetch_registers) (regno)
 453
 454 /* Store at least register REGNO, or all regs if REGNO == -1.
 455    It can store as many registers as it wants to, so target_prepare_to_store
 456    must have been previously called.  Calls error() if there are problems.  */
 457
 458 #define target_store_registers(regs)    \
 459      (*current_target.to_store_registers) (regs)
 460
 461 /* Get ready to modify the registers array.  On machines which store
 462    individual registers, this doesn't need to do anything.  On machines
 463    which store all the registers in one fell swoop, this makes sure
 464    that REGISTERS contains all the registers from the program being
 465    debugged.  */
 466
 467 #define target_prepare_to_store()       \
 468      (*current_target.to_prepare_to_store) ()
 469
 470 extern DCACHE *target_dcache;
 471
 472 extern int do_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
 473                            struct mem_attrib *attrib);
 474
 475 extern int target_read_string (CORE_ADDR, char **, int, int *);
 476
 477 extern int target_read_memory (CORE_ADDR memaddr, char *myaddr, int len);
 478
 479 extern int target_write_memory (CORE_ADDR memaddr, char *myaddr, int len);
 480
 481 extern int xfer_memory (CORE_ADDR, char *, int, int,
 482                         struct mem_attrib *, struct target_ops *);
 483
 484 extern int child_xfer_memory (CORE_ADDR, char *, int, int,
 485                               struct mem_attrib *, struct target_ops *);
 486
 487 /* Make a single attempt at transfering LEN bytes.  On a successful
 488    transfer, the number of bytes actually transfered is returned and
 489    ERR is set to 0.  When a transfer fails, -1 is returned (the number
 490    of bytes actually transfered is not defined) and ERR is set to a
 491    non-zero error indication.  */
 492
 493 extern int
 494 target_read_memory_partial (CORE_ADDR addr, char *buf, int len, int *err);
 495
 496 extern int
 497 target_write_memory_partial (CORE_ADDR addr, char *buf, int len, int *err);
 498
 499 extern char *child_pid_to_exec_file (int);
 500
 501 extern char *child_core_file_to_sym_file (char *);
 502
 503 #if defined(CHILD_POST_ATTACH)
 504 extern void child_post_attach (int);
 505 #endif
 506
 507 extern void child_post_wait (ptid_t, int);
 508
 509 extern void child_post_startup_inferior (ptid_t);
 510
 511 extern void child_acknowledge_created_inferior (int);
 512
 513 extern int child_insert_fork_catchpoint (int);
 514
 515 extern int child_remove_fork_catchpoint (int);
 516
 517 extern int child_insert_vfork_catchpoint (int);
 518
 519 extern int child_remove_vfork_catchpoint (int);
 520
 521 extern void child_acknowledge_created_inferior (int);
 522
 523 extern int child_follow_fork (int);
 524
 525 extern int child_insert_exec_catchpoint (int);
 526
 527 extern int child_remove_exec_catchpoint (int);
 528
 529 extern int child_reported_exec_events_per_exec_call (void);
 530
 531 extern int child_has_exited (int, int, int *);
 532
 533 extern int child_thread_alive (ptid_t);
 534
 535 /* From infrun.c.  */
 536
 537 extern int inferior_has_forked (int pid, int *child_pid);
 538
 539 extern int inferior_has_vforked (int pid, int *child_pid);
 540
 541 extern int inferior_has_execd (int pid, char **execd_pathname);
 542
 543 /* From exec.c */
 544
 545 extern void print_section_info (struct target_ops *, bfd *);
 546
 547 /* Print a line about the current target.  */
 548
 549 #define target_files_info()     \
 550      (*current_target.to_files_info) (&current_target)
 551
 552 /* Insert a breakpoint at address ADDR in the target machine.
 553    SAVE is a pointer to memory allocated for saving the
 554    target contents.  It is guaranteed by the caller to be long enough
 555    to save "sizeof BREAKPOINT" bytes.  Result is 0 for success, or
 556    an errno value.  */
 557
 558 #define target_insert_breakpoint(addr, save)    \
 559      (*current_target.to_insert_breakpoint) (addr, save)
 560
 561 /* Remove a breakpoint at address ADDR in the target machine.
 562    SAVE is a pointer to the same save area
 563    that was previously passed to target_insert_breakpoint.
 564    Result is 0 for success, or an errno value.  */
 565
 566 #define target_remove_breakpoint(addr, save)    \
 567      (*current_target.to_remove_breakpoint) (addr, save)
 568
 569 /* Initialize the terminal settings we record for the inferior,
 570    before we actually run the inferior.  */
 571
 572 #define target_terminal_init() \
 573      (*current_target.to_terminal_init) ()
 574
 575 /* Put the inferior's terminal settings into effect.
 576    This is preparation for starting or resuming the inferior.  */
 577
 578 #define target_terminal_inferior() \
 579      (*current_target.to_terminal_inferior) ()
 580
 581 /* Put some of our terminal settings into effect,
 582    enough to get proper results from our output,
 583    but do not change into or out of RAW mode
 584    so that no input is discarded.
 585
 586    After doing this, either terminal_ours or terminal_inferior
 587    should be called to get back to a normal state of affairs.  */
 588
 589 #define target_terminal_ours_for_output() \
 590      (*current_target.to_terminal_ours_for_output) ()
 591
 592 /* Put our terminal settings into effect.
 593    First record the inferior's terminal settings
 594    so they can be restored properly later.  */
 595
 596 #define target_terminal_ours() \
 597      (*current_target.to_terminal_ours) ()
 598
 599 /* Save our terminal settings.
 600    This is called from TUI after entering or leaving the curses
 601    mode.  Since curses modifies our terminal this call is here
 602    to take this change into account.  */
 603
 604 #define target_terminal_save_ours() \
 605      (*current_target.to_terminal_save_ours) ()
 606
 607 /* Print useful information about our terminal status, if such a thing
 608    exists.  */
 609
 610 #define target_terminal_info(arg, from_tty) \
 611      (*current_target.to_terminal_info) (arg, from_tty)
 612
 613 /* Kill the inferior process.   Make it go away.  */
 614
 615 #define target_kill() \
 616      (*current_target.to_kill) ()
 617
 618 /* Load an executable file into the target process.  This is expected
 619    to not only bring new code into the target process, but also to
 620    update GDB's symbol tables to match.  */
 621
 622 extern void target_load (char *arg, int from_tty);
 623
 624 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 625    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 626    symbol should be returned.  The result is 0 if successful, nonzero
 627    if the symbol does not exist in the target environment.  This
 628    function should not call error() if communication with the target
 629    is interrupted, since it is called from symbol reading, but should
 630    return nonzero, possibly doing a complain().  */
 631
 632 #define target_lookup_symbol(name, addrp) \
 633      (*current_target.to_lookup_symbol) (name, addrp)
 634
 635 /* Start an inferior process and set inferior_ptid to its pid.
 636    EXEC_FILE is the file to run.
 637    ALLARGS is a string containing the arguments to the program.
 638    ENV is the environment vector to pass.  Errors reported with error().
 639    On VxWorks and various standalone systems, we ignore exec_file.  */
 640
 641 #define target_create_inferior(exec_file, args, env)    \
 642      (*current_target.to_create_inferior) (exec_file, args, env)
 643
 644
 645 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 646    notification of inferior events such as fork and vork immediately
 647    after the inferior is created.  (This because of how gdb gets an
 648    inferior created via invoking a shell to do it.  In such a scenario,
 649    if the shell init file has commands in it, the shell will fork and
 650    exec for each of those commands, and we will see each such fork
 651    event.  Very bad.)
 652
 653    Such targets will supply an appropriate definition for this function.  */
 654
 655 #define target_post_startup_inferior(ptid) \
 656      (*current_target.to_post_startup_inferior) (ptid)
 657
 658 /* On some targets, the sequence of starting up an inferior requires
 659    some synchronization between gdb and the new inferior process, PID.  */
 660
 661 #define target_acknowledge_created_inferior(pid) \
 662      (*current_target.to_acknowledge_created_inferior) (pid)
 663
 664 /* On some targets, we can catch an inferior fork or vfork event when
 665    it occurs.  These functions insert/remove an already-created
 666    catchpoint for such events.  */
 667
 668 #define target_insert_fork_catchpoint(pid) \
 669      (*current_target.to_insert_fork_catchpoint) (pid)
 670
 671 #define target_remove_fork_catchpoint(pid) \
 672      (*current_target.to_remove_fork_catchpoint) (pid)
 673
 674 #define target_insert_vfork_catchpoint(pid) \
 675      (*current_target.to_insert_vfork_catchpoint) (pid)
 676
 677 #define target_remove_vfork_catchpoint(pid) \
 678      (*current_target.to_remove_vfork_catchpoint) (pid)
 679
 680 /* If the inferior forks or vforks, this function will be called at
 681    the next resume in order to perform any bookkeeping and fiddling
 682    necessary to continue debugging either the parent or child, as
 683    requested, and releasing the other.  Information about the fork
 684    or vfork event is available via get_last_target_status ().
 685    This function returns 1 if the inferior should not be resumed
 686    (i.e. there is another event pending).  */
 687
 688 #define target_follow_fork(follow_child) \
 689      (*current_target.to_follow_fork) (follow_child)
 690
 691 /* On some targets, we can catch an inferior exec event when it
 692    occurs.  These functions insert/remove an already-created
 693    catchpoint for such events.  */
 694
 695 #define target_insert_exec_catchpoint(pid) \
 696      (*current_target.to_insert_exec_catchpoint) (pid)
 697
 698 #define target_remove_exec_catchpoint(pid) \
 699      (*current_target.to_remove_exec_catchpoint) (pid)
 700
 701 /* Returns the number of exec events that are reported when a process
 702    invokes a flavor of the exec() system call on this target, if exec
 703    events are being reported.  */
 704
 705 #define target_reported_exec_events_per_exec_call() \
 706      (*current_target.to_reported_exec_events_per_exec_call) ()
 707
 708 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 709    exit code of PID, if any.  */
 710
 711 #define target_has_exited(pid,wait_status,exit_status) \
 712      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 713
 714 /* The debugger has completed a blocking wait() call.  There is now
 715    some process event that must be processed.  This function should
 716    be defined by those targets that require the debugger to perform
 717    cleanup or internal state changes in response to the process event.  */
 718
 719 /* The inferior process has died.  Do what is right.  */
 720
 721 #define target_mourn_inferior() \
 722      (*current_target.to_mourn_inferior) ()
 723
 724 /* Does target have enough data to do a run or attach command? */
 725
 726 #define target_can_run(t) \
 727      ((t)->to_can_run) ()
 728
 729 /* post process changes to signal handling in the inferior.  */
 730
 731 #define target_notice_signals(ptid) \
 732      (*current_target.to_notice_signals) (ptid)
 733
 734 /* Check to see if a thread is still alive.  */
 735
 736 #define target_thread_alive(ptid) \
 737      (*current_target.to_thread_alive) (ptid)
 738
 739 /* Query for new threads and add them to the thread list.  */
 740
 741 #define target_find_new_threads() \
 742      (*current_target.to_find_new_threads) (); \
 743
 744 /* Make target stop in a continuable fashion.  (For instance, under
 745    Unix, this should act like SIGSTOP).  This function is normally
 746    used by GUIs to implement a stop button.  */
 747
 748 #define target_stop current_target.to_stop
 749
 750 /* Queries the target side for some information.  The first argument is a
 751    letter specifying the type of the query, which is used to determine who
 752    should process it.  The second argument is a string that specifies which
 753    information is desired and the third is a buffer that carries back the
 754    response from the target side. The fourth parameter is the size of the
 755    output buffer supplied.  */
 756
 757 #define target_query(query_type, query, resp_buffer, bufffer_size)      \
 758      (*current_target.to_query) (query_type, query, resp_buffer, bufffer_size)
 759
 760 /* Send the specified COMMAND to the target's monitor
 761    (shell,interpreter) for execution.  The result of the query is
 762    placed in OUTBUF.  */
 763
 764 #define target_rcmd(command, outbuf) \
 765      (*current_target.to_rcmd) (command, outbuf)
 766
 767
 768 /* Get the symbol information for a breakpointable routine called when
 769    an exception event occurs.
 770    Intended mainly for C++, and for those
 771    platforms/implementations where such a callback mechanism is available,
 772    e.g. HP-UX with ANSI C++ (aCC).  Some compilers (e.g. g++) support
 773    different mechanisms for debugging exceptions.  */
 774
 775 #define target_enable_exception_callback(kind, enable) \
 776      (*current_target.to_enable_exception_callback) (kind, enable)
 777
 778 /* Get the current exception event kind -- throw or catch, etc.  */
 779
 780 #define target_get_current_exception_event() \
 781      (*current_target.to_get_current_exception_event) ()
 782
 783 /* Pointer to next target in the chain, e.g. a core file and an exec file.  */
 784
 785 #define target_next \
 786      (current_target.to_next)
 787
 788 /* Does the target include all of memory, or only part of it?  This
 789    determines whether we look up the target chain for other parts of
 790    memory if this target can't satisfy a request.  */
 791
 792 #define target_has_all_memory   \
 793      (current_target.to_has_all_memory)
 794
 795 /* Does the target include memory?  (Dummy targets don't.)  */
 796
 797 #define target_has_memory       \
 798      (current_target.to_has_memory)
 799
 800 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 801    we start a process.)  */
 802
 803 #define target_has_stack        \
 804      (current_target.to_has_stack)
 805
 806 /* Does the target have registers?  (Exec files don't.)  */
 807
 808 #define target_has_registers    \
 809      (current_target.to_has_registers)
 810
 811 /* Does the target have execution?  Can we make it jump (through
 812    hoops), or pop its stack a few times?  FIXME: If this is to work that
 813    way, it needs to check whether an inferior actually exists.
 814    remote-udi.c and probably other targets can be the current target
 815    when the inferior doesn't actually exist at the moment.  Right now
 816    this just tells us whether this target is *capable* of execution.  */
 817
 818 #define target_has_execution    \
 819      (current_target.to_has_execution)
 820
 821 /* Can the target support the debugger control of thread execution?
 822    a) Can it lock the thread scheduler?
 823    b) Can it switch the currently running thread?  */
 824
 825 #define target_can_lock_scheduler \
 826      (current_target.to_has_thread_control & tc_schedlock)
 827
 828 #define target_can_switch_threads \
 829      (current_target.to_has_thread_control & tc_switch)
 830
 831 /* Can the target support asynchronous execution? */
 832 #define target_can_async_p() (current_target.to_can_async_p ())
 833
 834 /* Is the target in asynchronous execution mode? */
 835 #define target_is_async_p() (current_target.to_is_async_p())
 836
 837 /* Put the target in async mode with the specified callback function. */
 838 #define target_async(CALLBACK,CONTEXT) \
 839      (current_target.to_async((CALLBACK), (CONTEXT)))
 840
 841 /* This is to be used ONLY within run_stack_dummy(). It
 842    provides a workaround, to have inferior function calls done in
 843    sychronous mode, even though the target is asynchronous. After
 844    target_async_mask(0) is called, calls to target_can_async_p() will
 845    return FALSE , so that target_resume() will not try to start the
 846    target asynchronously. After the inferior stops, we IMMEDIATELY
 847    restore the previous nature of the target, by calling
 848    target_async_mask(1). After that, target_can_async_p() will return
 849    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
 850
 851    FIXME ezannoni 1999-12-13: we won't need this once we move
 852    the turning async on and off to the single execution commands,
 853    from where it is done currently, in remote_resume().  */
 854
 855 #define target_async_mask_value \
 856      (current_target.to_async_mask_value)
 857
 858 extern int target_async_mask (int mask);
 859
 860 extern void target_link (char *, CORE_ADDR *);
 861
 862 /* Converts a process id to a string.  Usually, the string just contains
 863    `process xyz', but on some systems it may contain
 864    `process xyz thread abc'.  */
 865
 866 #undef target_pid_to_str
 867 #define target_pid_to_str(PID) current_target.to_pid_to_str (PID)
 868
 869 #ifndef target_tid_to_str
 870 #define target_tid_to_str(PID) \
 871      target_pid_to_str (PID)
 872 extern char *normal_pid_to_str (ptid_t ptid);
 873 #endif
 874
 875 /* Return a short string describing extra information about PID,
 876    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
 877    is okay.  */
 878
 879 #define target_extra_thread_info(TP) \
 880      (current_target.to_extra_thread_info (TP))
 881
 882 /*
 883  * New Objfile Event Hook:
 884  *
 885  * Sometimes a GDB component wants to get notified whenever a new
 886  * objfile is loaded.  Mainly this is used by thread-debugging
 887  * implementations that need to know when symbols for the target
 888  * thread implemenation are available.
 889  *
 890  * The old way of doing this is to define a macro 'target_new_objfile'
 891  * that points to the function that you want to be called on every
 892  * objfile/shlib load.
 893  *
 894  * The new way is to grab the function pointer, 'target_new_objfile_hook',
 895  * and point it to the function that you want to be called on every
 896  * objfile/shlib load.
 897  *
 898  * If multiple clients are willing to be cooperative, they can each
 899  * save a pointer to the previous value of target_new_objfile_hook
 900  * before modifying it, and arrange for their function to call the
 901  * previous function in the chain.  In that way, multiple clients
 902  * can receive this notification (something like with signal handlers).
 903  */
 904
 905 extern void (*target_new_objfile_hook) (struct objfile *);
 906
 907 #ifndef target_pid_or_tid_to_str
 908 #define target_pid_or_tid_to_str(ID) \
 909      target_pid_to_str (ID)
 910 #endif
 911
 912 /* Attempts to find the pathname of the executable file
 913    that was run to create a specified process.
 914
 915    The process PID must be stopped when this operation is used.
 916
 917    If the executable file cannot be determined, NULL is returned.
 918
 919    Else, a pointer to a character string containing the pathname
 920    is returned.  This string should be copied into a buffer by
 921    the client if the string will not be immediately used, or if
 922    it must persist.  */
 923
 924 #define target_pid_to_exec_file(pid) \
 925      (current_target.to_pid_to_exec_file) (pid)
 926
 927 /*
 928  * Iterator function for target memory regions.
 929  * Calls a callback function once for each memory region 'mapped'
 930  * in the child process.  Defined as a simple macro rather than
 931  * as a function macro so that it can be tested for nullity.
 932  */
 933
 934 #define target_find_memory_regions(FUNC, DATA) \
 935      (current_target.to_find_memory_regions) (FUNC, DATA)
 936
 937 /*
 938  * Compose corefile .note section.
 939  */
 940
 941 #define target_make_corefile_notes(BFD, SIZE_P) \
 942      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
 943
 944 /* Thread-local values.  */
 945 #define target_get_thread_local_address \
 946     (current_target.to_get_thread_local_address)
 947 #define target_get_thread_local_address_p() \
 948     (target_get_thread_local_address != NULL)
 949
 950 /* Hook to call target-dependent code after reading in a new symbol table.  */
 951
 952 #ifndef TARGET_SYMFILE_POSTREAD
 953 #define TARGET_SYMFILE_POSTREAD(OBJFILE)
 954 #endif
 955
 956 /* Hook to call target dependent code just after inferior target process has
 957    started.  */
 958
 959 #ifndef TARGET_CREATE_INFERIOR_HOOK
 960 #define TARGET_CREATE_INFERIOR_HOOK(PID)
 961 #endif
 962
 963 /* Hardware watchpoint interfaces.  */
 964
 965 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
 966    write).  */
 967
 968 #ifndef STOPPED_BY_WATCHPOINT
 969 #define STOPPED_BY_WATCHPOINT(w) \
 970    (*current_target.to_stopped_by_watchpoint) ()
 971 #endif
 972
 973 /* HP-UX supplies these operations, which respectively disable and enable
 974    the memory page-protections that are used to implement hardware watchpoints
 975    on that platform.  See wait_for_inferior's use of these.  */
 976
 977 #if !defined(TARGET_DISABLE_HW_WATCHPOINTS)
 978 #define TARGET_DISABLE_HW_WATCHPOINTS(pid)
 979 #endif
 980
 981 #if !defined(TARGET_ENABLE_HW_WATCHPOINTS)
 982 #define TARGET_ENABLE_HW_WATCHPOINTS(pid)
 983 #endif
 984
 985 /* Provide defaults for hardware watchpoint functions.  */
 986
 987 /* If the *_hw_beakpoint functions have not been defined
 988    elsewhere use the definitions in the target vector.  */
 989
 990 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
 991    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
 992    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
 993    (including this one?).  OTHERTYPE is who knows what...  */
 994
 995 #ifndef TARGET_CAN_USE_HARDWARE_WATCHPOINT
 996 #define TARGET_CAN_USE_HARDWARE_WATCHPOINT(TYPE,CNT,OTHERTYPE) \
 997  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
 998 #endif
 999
1000 #if !defined(TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT)
1001 #define TARGET_REGION_SIZE_OK_FOR_HW_WATCHPOINT(byte_count) \
1002     (*current_target.to_region_size_ok_for_hw_watchpoint) (byte_count)
1003 #endif
1004
1005
1006 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1007    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1008    success, non-zero for failure.  */
1009
1010 #ifndef target_insert_watchpoint
1011 #define target_insert_watchpoint(addr, len, type)       \
1012      (*current_target.to_insert_watchpoint) (addr, len, type)
1013
1014 #define target_remove_watchpoint(addr, len, type)       \
1015      (*current_target.to_remove_watchpoint) (addr, len, type)
1016 #endif
1017
1018 #ifndef target_insert_hw_breakpoint
1019 #define target_insert_hw_breakpoint(addr, save) \
1020      (*current_target.to_insert_hw_breakpoint) (addr, save)
1021
1022 #define target_remove_hw_breakpoint(addr, save) \
1023      (*current_target.to_remove_hw_breakpoint) (addr, save)
1024 #endif
1025
1026 #ifndef target_stopped_data_address
1027 #define target_stopped_data_address() \
1028     (*current_target.to_stopped_data_address) ()
1029 #endif
1030
1031 /* If defined, then we need to decr pc by this much after a hardware break-
1032    point.  Presumably this overrides DECR_PC_AFTER_BREAK...  */
1033
1034 #ifndef DECR_PC_AFTER_HW_BREAK
1035 #define DECR_PC_AFTER_HW_BREAK 0
1036 #endif
1037
1038 /* Sometimes gdb may pick up what appears to be a valid target address
1039    from a minimal symbol, but the value really means, essentially,
1040    "This is an index into a table which is populated when the inferior
1041    is run.  Therefore, do not attempt to use this as a PC."  */
1042
1043 #if !defined(PC_REQUIRES_RUN_BEFORE_USE)
1044 #define PC_REQUIRES_RUN_BEFORE_USE(pc) (0)
1045 #endif
1046
1047 /* This will only be defined by a target that supports catching vfork events,
1048    such as HP-UX.
1049
1050    On some targets (such as HP-UX 10.20 and earlier), resuming a newly vforked
1051    child process after it has exec'd, causes the parent process to resume as
1052    well.  To prevent the parent from running spontaneously, such targets should
1053    define this to a function that prevents that from happening.  */
1054 #if !defined(ENSURE_VFORKING_PARENT_REMAINS_STOPPED)
1055 #define ENSURE_VFORKING_PARENT_REMAINS_STOPPED(PID) (0)
1056 #endif
1057
1058 /* This will only be defined by a target that supports catching vfork events,
1059    such as HP-UX.
1060
1061    On some targets (such as HP-UX 10.20 and earlier), a newly vforked child
1062    process must be resumed when it delivers its exec event, before the parent
1063    vfork event will be delivered to us.  */
1064
1065 #if !defined(RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK)
1066 #define RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK() (0)
1067 #endif
1068
1069 /* Routines for maintenance of the target structures...
1070
1071    add_target:   Add a target to the list of all possible targets.
1072
1073    push_target:  Make this target the top of the stack of currently used
1074    targets, within its particular stratum of the stack.  Result
1075    is 0 if now atop the stack, nonzero if not on top (maybe
1076    should warn user).
1077
1078    unpush_target: Remove this from the stack of currently used targets,
1079    no matter where it is on the list.  Returns 0 if no
1080    change, 1 if removed from stack.
1081
1082    pop_target:   Remove the top thing on the stack of current targets.  */
1083
1084 extern void add_target (struct target_ops *);
1085
1086 extern int push_target (struct target_ops *);
1087
1088 extern int unpush_target (struct target_ops *);
1089
1090 extern void target_preopen (int);
1091
1092 extern void pop_target (void);
1093
1094 /* Struct section_table maps address ranges to file sections.  It is
1095    mostly used with BFD files, but can be used without (e.g. for handling
1096    raw disks, or files not in formats handled by BFD).  */
1097
1098 struct section_table
1099   {
1100     CORE_ADDR addr;             /* Lowest address in section */
1101     CORE_ADDR endaddr;          /* 1+highest address in section */
1102
1103     sec_ptr the_bfd_section;
1104
1105     bfd *bfd;                   /* BFD file pointer */
1106   };
1107
1108 /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR.
1109    Returns 0 if OK, 1 on error.  */
1110
1111 extern int
1112 build_section_table (bfd *, struct section_table **, struct section_table **);
1113
1114 /* From mem-break.c */
1115
1116 extern int memory_remove_breakpoint (CORE_ADDR, char *);
1117
1118 extern int memory_insert_breakpoint (CORE_ADDR, char *);
1119
1120 extern int default_memory_remove_breakpoint (CORE_ADDR, char *);
1121
1122 extern int default_memory_insert_breakpoint (CORE_ADDR, char *);
1123
1124 extern const unsigned char *memory_breakpoint_from_pc (CORE_ADDR *pcptr,
1125                                                        int *lenptr);
1126
1127
1128 /* From target.c */
1129
1130 extern void initialize_targets (void);
1131
1132 extern void noprocess (void);
1133
1134 extern void find_default_attach (char *, int);
1135
1136 extern void find_default_create_inferior (char *, char *, char **);
1137
1138 extern struct target_ops *find_run_target (void);
1139
1140 extern struct target_ops *find_core_target (void);
1141
1142 extern struct target_ops *find_target_beneath (struct target_ops *);
1143
1144 extern int
1145 target_resize_to_sections (struct target_ops *target, int num_added);
1146
1147 extern void remove_target_sections (bfd *abfd);
1148
1149 \f
1150 /* Stuff that should be shared among the various remote targets.  */
1151
1152 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1153    information (higher values, more information).  */
1154 extern int remote_debug;
1155
1156 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1157 extern int baud_rate;
1158 /* Timeout limit for response from target. */
1159 extern int remote_timeout;
1160
1161 \f
1162 /* Functions for helping to write a native target.  */
1163
1164 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1165 extern void store_waitstatus (struct target_waitstatus *, int);
1166
1167 /* Predicate to target_signal_to_host(). Return non-zero if the enum
1168    targ_signal SIGNO has an equivalent ``host'' representation.  */
1169 /* FIXME: cagney/1999-11-22: The name below was chosen in preference
1170    to the shorter target_signal_p() because it is far less ambigious.
1171    In this context ``target_signal'' refers to GDB's internal
1172    representation of the target's set of signals while ``host signal''
1173    refers to the target operating system's signal.  Confused?  */
1174
1175 extern int target_signal_to_host_p (enum target_signal signo);
1176
1177 /* Convert between host signal numbers and enum target_signal's.
1178    target_signal_to_host() returns 0 and prints a warning() on GDB's
1179    console if SIGNO has no equivalent host representation.  */
1180 /* FIXME: cagney/1999-11-22: Here ``host'' is used incorrectly, it is
1181    refering to the target operating system's signal numbering.
1182    Similarly, ``enum target_signal'' is named incorrectly, ``enum
1183    gdb_signal'' would probably be better as it is refering to GDB's
1184    internal representation of a target operating system's signal.  */
1185
1186 extern enum target_signal target_signal_from_host (int);
1187 extern int target_signal_to_host (enum target_signal);
1188
1189 /* Convert from a number used in a GDB command to an enum target_signal.  */
1190 extern enum target_signal target_signal_from_command (int);
1191
1192 /* Any target can call this to switch to remote protocol (in remote.c). */
1193 extern void push_remote_target (char *name, int from_tty);
1194 \f
1195 /* Imported from machine dependent code */
1196
1197 /* Blank target vector entries are initialized to target_ignore. */
1198 void target_ignore (void);
1199
1200 #endif /* !defined (TARGET_H) */