gdb/breakpoint.h

   1 /* Data structures associated with breakpoints in GDB.
   2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
   3    2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #if !defined (BREAKPOINT_H)
  21 #define BREAKPOINT_H 1
  22
  23 #include "frame.h"
  24 #include "value.h"
  25 #include "vec.h"
  26
  27 #include "gdb-events.h"
  28
  29 struct value;
  30 struct block;
  31
  32 /* This is the maximum number of bytes a breakpoint instruction can take.
  33    Feel free to increase it.  It's just used in a few places to size
  34    arrays that should be independent of the target architecture.  */
  35
  36 #define BREAKPOINT_MAX  16
  37 \f
  38 /* Type of breakpoint. */
  39 /* FIXME In the future, we should fold all other breakpoint-like things into
  40    here.  This includes:
  41
  42    * single-step (for machines where we have to simulate single stepping)
  43    (probably, though perhaps it is better for it to look as much as
  44    possible like a single-step to wait_for_inferior).  */
  45
  46 enum bptype
  47   {
  48     bp_none = 0,                /* Eventpoint has been deleted. */
  49     bp_breakpoint,              /* Normal breakpoint */
  50     bp_hardware_breakpoint,     /* Hardware assisted breakpoint */
  51     bp_until,                   /* used by until command */
  52     bp_finish,                  /* used by finish command */
  53     bp_watchpoint,              /* Watchpoint */
  54     bp_hardware_watchpoint,     /* Hardware assisted watchpoint */
  55     bp_read_watchpoint,         /* read watchpoint, (hardware assisted) */
  56     bp_access_watchpoint,       /* access watchpoint, (hardware assisted) */
  57     bp_longjmp,                 /* secret breakpoint to find longjmp() */
  58     bp_longjmp_resume,          /* secret breakpoint to escape longjmp() */
  59
  60     /* Used by wait_for_inferior for stepping over subroutine calls, for
  61        stepping over signal handlers, and for skipping prologues.  */
  62     bp_step_resume,
  63
  64     /* Used to detect when a watchpoint expression has gone out of
  65        scope.  These breakpoints are usually not visible to the user.
  66
  67        This breakpoint has some interesting properties:
  68
  69        1) There's always a 1:1 mapping between watchpoints
  70        on local variables and watchpoint_scope breakpoints.
  71
  72        2) It automatically deletes itself and the watchpoint it's
  73        associated with when hit.
  74
  75        3) It can never be disabled.  */
  76     bp_watchpoint_scope,
  77
  78     /* The breakpoint at the end of a call dummy.  */
  79     /* FIXME: What if the function we are calling longjmp()s out of the
  80        call, or the user gets out with the "return" command?  We currently
  81        have no way of cleaning up the breakpoint in these (obscure) situations.
  82        (Probably can solve this by noticing longjmp, "return", etc., it's
  83        similar to noticing when a watchpoint on a local variable goes out
  84        of scope (with hardware support for watchpoints)).  */
  85     bp_call_dummy,
  86
  87     /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
  88        code in the inferior to run when significant events occur in the
  89        dynamic linker (for example a library is loaded or unloaded).
  90
  91        By placing a breakpoint in this magic code GDB will get control
  92        when these significant events occur.  GDB can then re-examine
  93        the dynamic linker's data structures to discover any newly loaded
  94        dynamic libraries.  */
  95     bp_shlib_event,
  96
  97     /* Some multi-threaded systems can arrange for a location in the
  98        inferior to be executed when certain thread-related events occur
  99        (such as thread creation or thread death).
 100
 101        By placing a breakpoint at one of these locations, GDB will get
 102        control when these events occur.  GDB can then update its thread
 103        lists etc.  */
 104
 105     bp_thread_event,
 106
 107     /* On the same principal, an overlay manager can arrange to call a
 108        magic location in the inferior whenever there is an interesting
 109        change in overlay status.  GDB can update its overlay tables
 110        and fiddle with breakpoints in overlays when this breakpoint
 111        is hit.  */
 112
 113     bp_overlay_event,
 114
 115     /* These breakpoints are used to implement the "catch load" command
 116        on platforms whose dynamic linkers support such functionality.  */
 117     bp_catch_load,
 118
 119     /* These breakpoints are used to implement the "catch unload" command
 120        on platforms whose dynamic linkers support such functionality.  */
 121     bp_catch_unload,
 122
 123     /* These are not really breakpoints, but are catchpoints that
 124        implement the "catch fork", "catch vfork" and "catch exec" commands
 125        on platforms whose kernel support such functionality.  (I.e.,
 126        kernels which can raise an event when a fork or exec occurs, as
 127        opposed to the debugger setting breakpoints on functions named
 128        "fork" or "exec".) */
 129     bp_catch_fork,
 130     bp_catch_vfork,
 131     bp_catch_exec,
 132   };
 133
 134 /* States of enablement of breakpoint. */
 135
 136 enum enable_state
 137   {
 138     bp_disabled,        /* The eventpoint is inactive, and cannot trigger. */
 139     bp_enabled,         /* The eventpoint is active, and can trigger. */
 140     bp_call_disabled,   /* The eventpoint has been disabled while a call
 141                            into the inferior is "in flight", because some
 142                            eventpoints interfere with the implementation of
 143                            a call on some targets.  The eventpoint will be
 144                            automatically enabled and reset when the call
 145                            "lands" (either completes, or stops at another
 146                            eventpoint). */
 147     bp_permanent        /* There is a breakpoint instruction hard-wired into
 148                            the target's code.  Don't try to write another
 149                            breakpoint instruction on top of it, or restore
 150                            its value.  Step over it using the architecture's
 151                            SKIP_INSN macro.  */
 152   };
 153
 154
 155 /* Disposition of breakpoint.  Ie: what to do after hitting it. */
 156
 157 enum bpdisp
 158   {
 159     disp_del,                   /* Delete it */
 160     disp_del_at_next_stop,      /* Delete at next stop, whether hit or not */
 161     disp_disable,               /* Disable it */
 162     disp_donttouch              /* Leave it alone */
 163   };
 164
 165 enum target_hw_bp_type
 166   {
 167     hw_write   = 0,             /* Common  HW watchpoint */
 168     hw_read    = 1,             /* Read    HW watchpoint */
 169     hw_access  = 2,             /* Access  HW watchpoint */
 170     hw_execute = 3              /* Execute HW breakpoint */
 171   };
 172
 173
 174 /* Information used by targets to insert and remove breakpoints.  */
 175
 176 struct bp_target_info
 177 {
 178   /* Address at which the breakpoint was placed.  This is normally the
 179      same as ADDRESS from the bp_location, except when adjustment
 180      happens in gdbarch_breakpoint_from_pc.  The most common form of
 181      adjustment is stripping an alternate ISA marker from the PC which
 182      is used to determine the type of breakpoint to insert.  */
 183   CORE_ADDR placed_address;
 184
 185   /* If the breakpoint lives in memory and reading that memory would
 186      give back the breakpoint, instead of the original contents, then
 187      the original contents are cached here.  Only SHADOW_LEN bytes of
 188      this buffer are valid, and only when the breakpoint is inserted.  */
 189   gdb_byte shadow_contents[BREAKPOINT_MAX];
 190
 191   /* The length of the data cached in SHADOW_CONTENTS.  */
 192   int shadow_len;
 193
 194   /* The size of the placed breakpoint, according to
 195      gdbarch_breakpoint_from_pc, when the breakpoint was inserted.  This is
 196      generally the same as SHADOW_LEN, unless we did not need
 197      to read from the target to implement the memory breakpoint
 198      (e.g. if a remote stub handled the details).  We may still
 199      need the size to remove the breakpoint safely.  */
 200   int placed_size;
 201 };
 202
 203 /* GDB maintains two types of information about each breakpoint (or
 204    watchpoint, or other related event).  The first type corresponds
 205    to struct breakpoint; this is a relatively high-level structure
 206    which contains the source location(s), stopping conditions, user
 207    commands to execute when the breakpoint is hit, and so forth.
 208
 209    The second type of information corresponds to struct bp_location.
 210    Each breakpoint has one or (eventually) more locations associated
 211    with it, which represent target-specific and machine-specific
 212    mechanisms for stopping the program.  For instance, a watchpoint
 213    expression may require multiple hardware watchpoints in order to
 214    catch all changes in the value of the expression being watched.  */
 215
 216 enum bp_loc_type
 217 {
 218   bp_loc_software_breakpoint,
 219   bp_loc_hardware_breakpoint,
 220   bp_loc_hardware_watchpoint,
 221   bp_loc_other                  /* Miscellaneous...  */
 222 };
 223
 224 struct bp_location
 225 {
 226   /* Chain pointer to the next breakpoint location for
 227      the same parent breakpoint.  */
 228   struct bp_location *next;
 229
 230   /* Pointer to the next breakpoint location, in a global
 231      list of all breakpoint locations.  */
 232   struct bp_location *global_next;
 233
 234   /* Type of this breakpoint location.  */
 235   enum bp_loc_type loc_type;
 236
 237   /* Each breakpoint location must belong to exactly one higher-level
 238      breakpoint.  This and the DUPLICATE flag are more straightforward
 239      than reference counting.  */
 240   struct breakpoint *owner;
 241
 242   /* Conditional.  Break only if this expression's value is nonzero.
 243      Unlike string form of condition, which is associated with breakpoint,
 244      this is associated with location, since if breakpoint has several
 245      locations,  the evaluation of expression can be different for
 246      different locations.  */
 247   struct expression *cond;
 248
 249   /* This location's address is in an unloaded solib, and so this
 250      location should not be inserted.  It will be automatically
 251      enabled when that solib is loaded.  */
 252   char shlib_disabled;
 253
 254   /* Is this particular location enabled.  */
 255   char enabled;
 256
 257   /* Nonzero if this breakpoint is now inserted.  */
 258   char inserted;
 259
 260   /* Nonzero if this is not the first breakpoint in the list
 261      for the given address.  */
 262   char duplicate;
 263
 264   /* If we someday support real thread-specific breakpoints, then
 265      the breakpoint location will need a thread identifier.  */
 266
 267   /* Data for specific breakpoint types.  These could be a union, but
 268      simplicity is more important than memory usage for breakpoints.  */
 269
 270   /* Note that zero is a perfectly valid code address on some platforms
 271      (for example, the mn10200 (OBSOLETE) and mn10300 simulators).  NULL
 272      is not a special value for this field.  Valid for all types except
 273      bp_loc_other.  */
 274   CORE_ADDR address;
 275
 276   /* For any breakpoint type with an address, this is the BFD section
 277      associated with the address.  Used primarily for overlay debugging.  */
 278   asection *section;
 279
 280   /* Address at which breakpoint was requested, either by the user or
 281      by GDB for internal breakpoints.  This will usually be the same
 282      as ``address'' (above) except for cases in which
 283      ADJUST_BREAKPOINT_ADDRESS has computed a different address at
 284      which to place the breakpoint in order to comply with a
 285      processor's architectual constraints.  */
 286   CORE_ADDR requested_address;
 287
 288   char *function_name;
 289
 290   /* Details of the placed breakpoint, when inserted.  */
 291   struct bp_target_info target_info;
 292
 293   /* Similarly, for the breakpoint at an overlay's LMA, if necessary.  */
 294   struct bp_target_info overlay_target_info;
 295 };
 296
 297 /* This structure is a collection of function pointers that, if available,
 298    will be called instead of the performing the default action for this
 299    bptype.  */
 300
 301 struct breakpoint_ops
 302 {
 303   /* The normal print routine for this breakpoint, called when we
 304      hit it.  */
 305   enum print_stop_action (*print_it) (struct breakpoint *);
 306
 307   /* Display information about this breakpoint, for "info breakpoints".  */
 308   void (*print_one) (struct breakpoint *, CORE_ADDR *);
 309
 310   /* Display information about this breakpoint after setting it (roughly
 311      speaking; this is called from "mention").  */
 312   void (*print_mention) (struct breakpoint *);
 313 };
 314
 315 enum watchpoint_triggered
 316 {
 317   /* This watchpoint definitely did not trigger.  */
 318   watch_triggered_no = 0,
 319
 320   /* Some hardware watchpoint triggered, and it might have been this
 321      one, but we do not know which it was.  */
 322   watch_triggered_unknown,
 323
 324   /* This hardware watchpoint definitely did trigger.  */
 325   watch_triggered_yes
 326 };
 327
 328 /* Note that the ->silent field is not currently used by any commands
 329    (though the code is in there if it was to be, and set_raw_breakpoint
 330    does set it to 0).  I implemented it because I thought it would be
 331    useful for a hack I had to put in; I'm going to leave it in because
 332    I can see how there might be times when it would indeed be useful */
 333
 334 /* This is for a breakpoint or a watchpoint.  */
 335
 336 struct breakpoint
 337   {
 338     struct breakpoint *next;
 339     /* Type of breakpoint. */
 340     enum bptype type;
 341     /* Zero means disabled; remember the info but don't break here.  */
 342     enum enable_state enable_state;
 343     /* What to do with this breakpoint after we hit it. */
 344     enum bpdisp disposition;
 345     /* Number assigned to distinguish breakpoints.  */
 346     int number;
 347
 348     /* Location(s) associated with this high-level breakpoint.  */
 349     struct bp_location *loc;
 350
 351     /* Line number of this address.  */
 352
 353     int line_number;
 354
 355     /* Source file name of this address.  */
 356
 357     char *source_file;
 358
 359     /* Non-zero means a silent breakpoint (don't print frame info
 360        if we stop here). */
 361     unsigned char silent;
 362     /* Number of stops at this breakpoint that should
 363        be continued automatically before really stopping.  */
 364     int ignore_count;
 365     /* Chain of command lines to execute when this breakpoint is hit.  */
 366     struct command_line *commands;
 367     /* Stack depth (address of frame).  If nonzero, break only if fp
 368        equals this.  */
 369     struct frame_id frame_id;
 370
 371     /* String we used to set the breakpoint (malloc'd).  */
 372     char *addr_string;
 373     /* Language we used to set the breakpoint.  */
 374     enum language language;
 375     /* Input radix we used to set the breakpoint.  */
 376     int input_radix;
 377     /* String form of the breakpoint condition (malloc'd), or NULL if there
 378        is no condition.  */
 379     char *cond_string;
 380     /* String form of exp (malloc'd), or NULL if none.  */
 381     char *exp_string;
 382
 383     /* The expression we are watching, or NULL if not a watchpoint.  */
 384     struct expression *exp;
 385     /* The largest block within which it is valid, or NULL if it is
 386        valid anywhere (e.g. consists just of global symbols).  */
 387     struct block *exp_valid_block;
 388     /* Value of the watchpoint the last time we checked it.  */
 389     struct value *val;
 390
 391     /* Holds the value chain for a hardware watchpoint expression.  */
 392     struct value *val_chain;
 393
 394     /* Holds the address of the related watchpoint_scope breakpoint
 395        when using watchpoints on local variables (might the concept
 396        of a related breakpoint be useful elsewhere, if not just call
 397        it the watchpoint_scope breakpoint or something like that. FIXME).  */
 398     struct breakpoint *related_breakpoint;
 399
 400     /* Holds the frame address which identifies the frame this
 401        watchpoint should be evaluated in, or `null' if the watchpoint
 402        should be evaluated on the outermost frame.  */
 403     struct frame_id watchpoint_frame;
 404
 405     /* For hardware watchpoints, the triggered status according to the
 406        hardware.  */
 407     enum watchpoint_triggered watchpoint_triggered;
 408
 409     /* Thread number for thread-specific breakpoint, or -1 if don't care */
 410     int thread;
 411
 412     /* Count of the number of times this breakpoint was taken, dumped
 413        with the info, but not used for anything else.  Useful for
 414        seeing how many times you hit a break prior to the program
 415        aborting, so you can back up to just before the abort.  */
 416     int hit_count;
 417
 418     /* Filename of a dynamically-linked library (dll), used for
 419        bp_catch_load and bp_catch_unload (malloc'd), or NULL if any
 420        library is significant.  */
 421     char *dll_pathname;
 422
 423     /* Filename of a dll whose state change (e.g., load or unload)
 424        triggered this catchpoint.  This field is only valid immediately
 425        after this catchpoint has triggered.  */
 426     char *triggered_dll_pathname;
 427
 428     /* Process id of a child process whose forking triggered this
 429        catchpoint.  This field is only valid immediately after this
 430        catchpoint has triggered.  */
 431     int forked_inferior_pid;
 432
 433     /* Filename of a program whose exec triggered this catchpoint.
 434        This field is only valid immediately after this catchpoint has
 435        triggered.  */
 436     char *exec_pathname;
 437
 438     /* Methods associated with this breakpoint.  */
 439     struct breakpoint_ops *ops;
 440
 441     /* Is breakpoint's condition not yet parsed because we found
 442        no location initially so had no context to parse
 443        the condition in.  */
 444     int condition_not_parsed;
 445   };
 446
 447 typedef struct breakpoint *breakpoint_p;
 448 DEF_VEC_P(breakpoint_p);
 449 \f
 450 /* The following stuff is an abstract data type "bpstat" ("breakpoint
 451    status").  This provides the ability to determine whether we have
 452    stopped at a breakpoint, and what we should do about it.  */
 453
 454 typedef struct bpstats *bpstat;
 455
 456 /* Frees any storage that is part of a bpstat.
 457    Does not walk the 'next' chain.  */
 458 extern void bpstat_free (bpstat);
 459
 460 /* Clears a chain of bpstat, freeing storage
 461    of each.  */
 462 extern void bpstat_clear (bpstat *);
 463
 464 /* Return a copy of a bpstat.  Like "bs1 = bs2" but all storage that
 465    is part of the bpstat is copied as well.  */
 466 extern bpstat bpstat_copy (bpstat);
 467
 468 extern bpstat bpstat_stop_status (CORE_ADDR pc, ptid_t ptid);
 469 \f
 470 /* This bpstat_what stuff tells wait_for_inferior what to do with a
 471    breakpoint (a challenging task).  */
 472
 473 enum bpstat_what_main_action
 474   {
 475     /* Perform various other tests; that is, this bpstat does not
 476        say to perform any action (e.g. failed watchpoint and nothing
 477        else).  */
 478     BPSTAT_WHAT_KEEP_CHECKING,
 479
 480     /* Rather than distinguish between noisy and silent stops here, it
 481        might be cleaner to have bpstat_print make that decision (also
 482        taking into account stop_print_frame and source_only).  But the
 483        implications are a bit scary (interaction with auto-displays, etc.),
 484        so I won't try it.  */
 485
 486     /* Stop silently.  */
 487     BPSTAT_WHAT_STOP_SILENT,
 488
 489     /* Stop and print.  */
 490     BPSTAT_WHAT_STOP_NOISY,
 491
 492     /* Remove breakpoints, single step once, then put them back in and
 493        go back to what we were doing.  It's possible that this should be
 494        removed from the main_action and put into a separate field, to more
 495        cleanly handle BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE.  */
 496     BPSTAT_WHAT_SINGLE,
 497
 498     /* Set longjmp_resume breakpoint, remove all other breakpoints,
 499        and continue.  The "remove all other breakpoints" part is required
 500        if we are also stepping over another breakpoint as well as doing
 501        the longjmp handling.  */
 502     BPSTAT_WHAT_SET_LONGJMP_RESUME,
 503
 504     /* Clear longjmp_resume breakpoint, then handle as
 505        BPSTAT_WHAT_KEEP_CHECKING.  */
 506     BPSTAT_WHAT_CLEAR_LONGJMP_RESUME,
 507
 508     /* Clear longjmp_resume breakpoint, then handle as BPSTAT_WHAT_SINGLE.  */
 509     BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE,
 510
 511     /* Clear step resume breakpoint, and keep checking.  */
 512     BPSTAT_WHAT_STEP_RESUME,
 513
 514     /* Check the dynamic linker's data structures for new libraries, then
 515        keep checking.  */
 516     BPSTAT_WHAT_CHECK_SHLIBS,
 517
 518     /* Check the dynamic linker's data structures for new libraries, then
 519        resume out of the dynamic linker's callback, stop and print.  */
 520     BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK,
 521
 522     /* This is just used to keep track of how many enums there are.  */
 523     BPSTAT_WHAT_LAST
 524   };
 525
 526 struct bpstat_what
 527   {
 528     enum bpstat_what_main_action main_action;
 529
 530     /* Did we hit a call dummy breakpoint?  This only goes with a main_action
 531        of BPSTAT_WHAT_STOP_SILENT or BPSTAT_WHAT_STOP_NOISY (the concept of
 532        continuing from a call dummy without popping the frame is not a
 533        useful one).  */
 534     int call_dummy;
 535   };
 536
 537 /* The possible return values for print_bpstat, print_it_normal,
 538    print_it_done, print_it_noop. */
 539 enum print_stop_action
 540   {
 541     PRINT_UNKNOWN = -1,
 542     PRINT_SRC_AND_LOC,
 543     PRINT_SRC_ONLY,
 544     PRINT_NOTHING
 545   };
 546
 547 /* Tell what to do about this bpstat.  */
 548 struct bpstat_what bpstat_what (bpstat);
 549 \f
 550 /* Find the bpstat associated with a breakpoint.  NULL otherwise. */
 551 bpstat bpstat_find_breakpoint (bpstat, struct breakpoint *);
 552
 553 /* Find a step_resume breakpoint associated with this bpstat.
 554    (If there are multiple step_resume bp's on the list, this function
 555    will arbitrarily pick one.)
 556
 557    It is an error to use this function if BPSTAT doesn't contain a
 558    step_resume breakpoint.
 559
 560    See wait_for_inferior's use of this function.
 561  */
 562 extern struct breakpoint *bpstat_find_step_resume_breakpoint (bpstat);
 563
 564 /* Nonzero if a signal that we got in wait() was due to circumstances
 565    explained by the BS.  */
 566 /* Currently that is true if we have hit a breakpoint, or if there is
 567    a watchpoint enabled.  */
 568 #define bpstat_explains_signal(bs) ((bs) != NULL)
 569
 570 /* Nonzero if we should step constantly (e.g. watchpoints on machines
 571    without hardware support).  This isn't related to a specific bpstat,
 572    just to things like whether watchpoints are set.  */
 573 extern int bpstat_should_step (void);
 574
 575 /* Print a message indicating what happened.  Returns nonzero to
 576    say that only the source line should be printed after this (zero
 577    return means print the frame as well as the source line).  */
 578 extern enum print_stop_action bpstat_print (bpstat);
 579
 580 /* Put in *NUM the breakpoint number of the first breakpoint we are stopped
 581    at.  *BSP upon return is a bpstat which points to the remaining
 582    breakpoints stopped at (but which is not guaranteed to be good for
 583    anything but further calls to bpstat_num).
 584    Return 0 if passed a bpstat which does not indicate any breakpoints.
 585    Return -1 if stopped at a breakpoint that has been deleted since
 586    we set it.
 587    Return 1 otherwise.  */
 588 extern int bpstat_num (bpstat *, int *);
 589
 590 /* Perform actions associated with having stopped at *BSP.  Actually, we just
 591    use this for breakpoint commands.  Perhaps other actions will go here
 592    later, but this is executed at a late time (from the command loop).  */
 593 extern void bpstat_do_actions (bpstat *);
 594
 595 /* Modify BS so that the actions will not be performed.  */
 596 extern void bpstat_clear_actions (bpstat);
 597
 598 /* Given a bpstat that records zero or more triggered eventpoints, this
 599    function returns another bpstat which contains only the catchpoints
 600    on that first list, if any.
 601  */
 602 extern void bpstat_get_triggered_catchpoints (bpstat, bpstat *);
 603
 604 /* Implementation:  */
 605
 606 /* Values used to tell the printing routine how to behave for this bpstat. */
 607 enum bp_print_how
 608   {
 609     /* This is used when we want to do a normal printing of the reason
 610        for stopping. The output will depend on the type of eventpoint
 611        we are dealing with. This is the default value, most commonly
 612        used. */
 613     print_it_normal,
 614     /* This is used when nothing should be printed for this bpstat entry.  */
 615     print_it_noop,
 616     /* This is used when everything which needs to be printed has
 617        already been printed.  But we still want to print the frame.  */
 618     print_it_done
 619   };
 620
 621 struct bpstats
 622   {
 623     /* Linked list because there can be two breakpoints at the same
 624        place, and a bpstat reflects the fact that both have been hit.  */
 625     bpstat next;
 626     /* Breakpoint that we are at.  */
 627     const struct bp_location *breakpoint_at;
 628     /* Commands left to be done.  */
 629     struct command_line *commands;
 630     /* Old value associated with a watchpoint.  */
 631     struct value *old_val;
 632
 633     /* Nonzero if this breakpoint tells us to print the frame.  */
 634     char print;
 635
 636     /* Nonzero if this breakpoint tells us to stop.  */
 637     char stop;
 638
 639     /* Tell bpstat_print and print_bp_stop_message how to print stuff
 640        associated with this element of the bpstat chain.  */
 641     enum bp_print_how print_it;
 642   };
 643
 644 enum inf_context
 645   {
 646     inf_starting,
 647     inf_running,
 648     inf_exited
 649   };
 650
 651 /* The possible return values for breakpoint_here_p.
 652    We guarantee that zero always means "no breakpoint here".  */
 653 enum breakpoint_here
 654   {
 655     no_breakpoint_here = 0,
 656     ordinary_breakpoint_here,
 657     permanent_breakpoint_here
 658   };
 659 \f
 660
 661 /* Prototypes for breakpoint-related functions.  */
 662
 663 extern enum breakpoint_here breakpoint_here_p (CORE_ADDR);
 664
 665 extern int breakpoint_inserted_here_p (CORE_ADDR);
 666
 667 extern int regular_breakpoint_inserted_here_p (CORE_ADDR);
 668
 669 extern int software_breakpoint_inserted_here_p (CORE_ADDR);
 670
 671 extern int breakpoint_thread_match (CORE_ADDR, ptid_t);
 672
 673 extern void until_break_command (char *, int, int);
 674
 675 extern void breakpoint_re_set (void);
 676
 677 extern void breakpoint_re_set_thread (struct breakpoint *);
 678
 679 extern int ep_is_exception_catchpoint (struct breakpoint *);
 680
 681 extern struct breakpoint *set_momentary_breakpoint
 682   (struct symtab_and_line, struct frame_id, enum bptype);
 683
 684 extern void set_ignore_count (int, int, int);
 685
 686 extern void set_default_breakpoint (int, CORE_ADDR, struct symtab *, int);
 687
 688 extern void breakpoint_init_inferior (enum inf_context);
 689
 690 extern struct cleanup *make_cleanup_delete_breakpoint (struct breakpoint *);
 691
 692 extern struct cleanup *make_exec_cleanup_delete_breakpoint (struct breakpoint *);
 693
 694 extern void delete_breakpoint (struct breakpoint *);
 695
 696 extern void breakpoint_auto_delete (bpstat);
 697
 698 extern void breakpoint_clear_ignore_counts (void);
 699
 700 extern void break_command (char *, int);
 701
 702 extern void hbreak_command_wrapper (char *, int);
 703 extern void thbreak_command_wrapper (char *, int);
 704 extern void rbreak_command_wrapper (char *, int);
 705 extern void watch_command_wrapper (char *, int);
 706 extern void awatch_command_wrapper (char *, int);
 707 extern void rwatch_command_wrapper (char *, int);
 708 extern void tbreak_command (char *, int);
 709
 710 extern void insert_breakpoints (void);
 711
 712 extern int remove_breakpoints (void);
 713
 714 /* This function can be used to physically insert eventpoints from the
 715    specified traced inferior process, without modifying the breakpoint
 716    package's state.  This can be useful for those targets which support
 717    following the processes of a fork() or vfork() system call, when both
 718    of the resulting two processes are to be followed.  */
 719 extern int reattach_breakpoints (int);
 720
 721 /* This function can be used to update the breakpoint package's state
 722    after an exec() system call has been executed.
 723
 724    This function causes the following:
 725
 726    - All eventpoints are marked "not inserted".
 727    - All eventpoints with a symbolic address are reset such that
 728    the symbolic address must be reevaluated before the eventpoints
 729    can be reinserted.
 730    - The solib breakpoints are explicitly removed from the breakpoint
 731    list.
 732    - A step-resume breakpoint, if any, is explicitly removed from the
 733    breakpoint list.
 734    - All eventpoints without a symbolic address are removed from the
 735    breakpoint list. */
 736 extern void update_breakpoints_after_exec (void);
 737
 738 /* This function can be used to physically remove hardware breakpoints
 739    and watchpoints from the specified traced inferior process, without
 740    modifying the breakpoint package's state.  This can be useful for
 741    those targets which support following the processes of a fork() or
 742    vfork() system call, when one of the resulting two processes is to
 743    be detached and allowed to run free.
 744
 745    It is an error to use this function on the process whose id is
 746    inferior_ptid.  */
 747 extern int detach_breakpoints (int);
 748
 749 extern void enable_longjmp_breakpoint (void);
 750 extern void disable_longjmp_breakpoint (void);
 751 extern void enable_overlay_breakpoints (void);
 752 extern void disable_overlay_breakpoints (void);
 753
 754 extern void set_longjmp_resume_breakpoint (CORE_ADDR, struct frame_id);
 755 /* These functions respectively disable or reenable all currently
 756    enabled watchpoints.  When disabled, the watchpoints are marked
 757    call_disabled.  When reenabled, they are marked enabled.
 758
 759    The intended client of these functions is call_function_by_hand.
 760
 761    The inferior must be stopped, and all breakpoints removed, when
 762    these functions are used.
 763
 764    The need for these functions is that on some targets (e.g., HP-UX),
 765    gdb is unable to unwind through the dummy frame that is pushed as
 766    part of the implementation of a call command.  Watchpoints can
 767    cause the inferior to stop in places where this frame is visible,
 768    and that can cause execution control to become very confused.
 769
 770    Note that if a user sets breakpoints in an interactively called
 771    function, the call_disabled watchpoints will have been reenabled
 772    when the first such breakpoint is reached.  However, on targets
 773    that are unable to unwind through the call dummy frame, watches
 774    of stack-based storage may then be deleted, because gdb will
 775    believe that their watched storage is out of scope.  (Sigh.) */
 776 extern void disable_watchpoints_before_interactive_call_start (void);
 777
 778 extern void enable_watchpoints_after_interactive_call_stop (void);
 779
 780 /* For script interpreters that need to define breakpoint commands
 781    after they've already read the commands into a struct command_line.  */
 782 extern enum command_control_type commands_from_control_command
 783   (char *arg, struct command_line *cmd);
 784
 785 extern void clear_breakpoint_hit_counts (void);
 786
 787 extern int get_number (char **);
 788
 789 extern int get_number_or_range (char **);
 790
 791 /* The following are for displays, which aren't really breakpoints, but
 792    here is as good a place as any for them.  */
 793
 794 extern void disable_current_display (void);
 795
 796 extern void do_displays (void);
 797
 798 extern void disable_display (int);
 799
 800 extern void clear_displays (void);
 801
 802 extern void disable_breakpoint (struct breakpoint *);
 803
 804 extern void enable_breakpoint (struct breakpoint *);
 805
 806 extern void make_breakpoint_permanent (struct breakpoint *);
 807
 808 extern struct breakpoint *create_solib_event_breakpoint (CORE_ADDR);
 809
 810 extern struct breakpoint *create_thread_event_breakpoint (CORE_ADDR);
 811
 812 extern void remove_solib_event_breakpoints (void);
 813
 814 extern void remove_thread_event_breakpoints (void);
 815
 816 extern void disable_breakpoints_in_shlibs (void);
 817
 818 /* This function returns TRUE if ep is a catchpoint. */
 819 extern int ep_is_catchpoint (struct breakpoint *);
 820
 821 /* This function returns TRUE if ep is a catchpoint of a
 822    shared library (aka dynamically-linked library) event,
 823    such as a library load or unload. */
 824 extern int ep_is_shlib_catchpoint (struct breakpoint *);
 825
 826 /* Enable breakpoints and delete when hit.  Called with ARG == NULL
 827    deletes all breakpoints. */
 828 extern void delete_command (char *arg, int from_tty);
 829
 830 /* Pull all H/W watchpoints from the target. Return non-zero if the
 831    remove fails. */
 832 extern int remove_hw_watchpoints (void);
 833
 834 /* Manage a software single step breakpoint (or two).  Insert may be called
 835    twice before remove is called.  */
 836 extern void insert_single_step_breakpoint (CORE_ADDR);
 837 extern void remove_single_step_breakpoints (void);
 838
 839 /* Manage manual breakpoints, separate from the normal chain of
 840    breakpoints.  These functions are used in murky target-specific
 841    ways.  Please do not add more uses!  */
 842 extern void *deprecated_insert_raw_breakpoint (CORE_ADDR);
 843 extern int deprecated_remove_raw_breakpoint (void *);
 844
 845 /* Check if any hardware watchpoints have triggered, according to the
 846    target.  */
 847 int watchpoints_triggered (struct target_waitstatus *);
 848
 849 #endif /* !defined (BREAKPOINT_H) */