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