gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2
   3    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   5    Free Software Foundation, Inc.
   6
   7    Contributed by Cygnus Support.  Written by John Gilmore.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #if !defined (TARGET_H)
  25 #define TARGET_H
  26
  27 struct objfile;
  28 struct ui_file;
  29 struct mem_attrib;
  30 struct target_ops;
  31 struct bp_target_info;
  32 struct regcache;
  33 struct target_section_table;
  34
  35 /* This include file defines the interface between the main part
  36    of the debugger, and the part which is target-specific, or
  37    specific to the communications interface between us and the
  38    target.
  39
  40    A TARGET is an interface between the debugger and a particular
  41    kind of file or process.  Targets can be STACKED in STRATA,
  42    so that more than one target can potentially respond to a request.
  43    In particular, memory accesses will walk down the stack of targets
  44    until they find a target that is interested in handling that particular
  45    address.  STRATA are artificial boundaries on the stack, within
  46    which particular kinds of targets live.  Strata exist so that
  47    people don't get confused by pushing e.g. a process target and then
  48    a file target, and wondering why they can't see the current values
  49    of variables any more (the file target is handling them and they
  50    never get to the process target).  So when you push a file target,
  51    it goes into the file stratum, which is always below the process
  52    stratum.  */
  53
  54 #include "bfd.h"
  55 #include "symtab.h"
  56 #include "dcache.h"
  57 #include "memattr.h"
  58 #include "vec.h"
  59 #include "gdb_signals.h"
  60
  61 enum strata
  62   {
  63     dummy_stratum,              /* The lowest of the low */
  64     file_stratum,               /* Executable files, etc */
  65     core_stratum,               /* Core dump files */
  66     process_stratum,            /* Executing processes */
  67     thread_stratum,             /* Executing threads */
  68     record_stratum              /* Support record debugging */
  69   };
  70
  71 enum thread_control_capabilities
  72   {
  73     tc_none = 0,                /* Default: can't control thread execution.  */
  74     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  75   };
  76
  77 /* Stuff for target_wait.  */
  78
  79 /* Generally, what has the program done?  */
  80 enum target_waitkind
  81   {
  82     /* The program has exited.  The exit status is in value.integer.  */
  83     TARGET_WAITKIND_EXITED,
  84
  85     /* The program has stopped with a signal.  Which signal is in
  86        value.sig.  */
  87     TARGET_WAITKIND_STOPPED,
  88
  89     /* The program has terminated with a signal.  Which signal is in
  90        value.sig.  */
  91     TARGET_WAITKIND_SIGNALLED,
  92
  93     /* The program is letting us know that it dynamically loaded something
  94        (e.g. it called load(2) on AIX).  */
  95     TARGET_WAITKIND_LOADED,
  96
  97     /* The program has forked.  A "related" process' PTID is in
  98        value.related_pid.  I.e., if the child forks, value.related_pid
  99        is the parent's ID.  */
 100
 101     TARGET_WAITKIND_FORKED,
 102
 103     /* The program has vforked.  A "related" process's PTID is in
 104        value.related_pid.  */
 105
 106     TARGET_WAITKIND_VFORKED,
 107
 108     /* The program has exec'ed a new executable file.  The new file's
 109        pathname is pointed to by value.execd_pathname.  */
 110
 111     TARGET_WAITKIND_EXECD,
 112
 113     /* The program has entered or returned from a system call.  On
 114        HP-UX, this is used in the hardware watchpoint implementation.
 115        The syscall's unique integer ID number is in value.syscall_id */
 116
 117     TARGET_WAITKIND_SYSCALL_ENTRY,
 118     TARGET_WAITKIND_SYSCALL_RETURN,
 119
 120     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 121        within target_wait, but I'm not sure target_wait should be resuming the
 122        inferior.  */
 123     TARGET_WAITKIND_SPURIOUS,
 124
 125     /* An event has occured, but we should wait again.
 126        Remote_async_wait() returns this when there is an event
 127        on the inferior, but the rest of the world is not interested in
 128        it. The inferior has not stopped, but has just sent some output
 129        to the console, for instance. In this case, we want to go back
 130        to the event loop and wait there for another event from the
 131        inferior, rather than being stuck in the remote_async_wait()
 132        function. This way the event loop is responsive to other events,
 133        like for instance the user typing.  */
 134     TARGET_WAITKIND_IGNORE,
 135
 136     /* The target has run out of history information,
 137        and cannot run backward any further.  */
 138     TARGET_WAITKIND_NO_HISTORY
 139   };
 140
 141 struct target_waitstatus
 142   {
 143     enum target_waitkind kind;
 144
 145     /* Forked child pid, execd pathname, exit status or signal number.  */
 146     union
 147       {
 148         int integer;
 149         enum target_signal sig;
 150         ptid_t related_pid;
 151         char *execd_pathname;
 152         int syscall_id;
 153       }
 154     value;
 155   };
 156
 157 /* Options that can be passed to target_wait.  */
 158
 159 /* Return immediately if there's no event already queued.  If this
 160    options is not requested, target_wait blocks waiting for an
 161    event.  */
 162 #define TARGET_WNOHANG 1
 163
 164 /* Return a pretty printed form of target_waitstatus.
 165    Space for the result is malloc'd, caller must free.  */
 166 extern char *target_waitstatus_to_string (const struct target_waitstatus *);
 167
 168 /* Possible types of events that the inferior handler will have to
 169    deal with.  */
 170 enum inferior_event_type
 171   {
 172     /* There is a request to quit the inferior, abandon it.  */
 173     INF_QUIT_REQ,
 174     /* Process a normal inferior event which will result in target_wait
 175        being called.  */
 176     INF_REG_EVENT,
 177     /* Deal with an error on the inferior.  */
 178     INF_ERROR,
 179     /* We are called because a timer went off.  */
 180     INF_TIMER,
 181     /* We are called to do stuff after the inferior stops.  */
 182     INF_EXEC_COMPLETE,
 183     /* We are called to do some stuff after the inferior stops, but we
 184        are expected to reenter the proceed() and
 185        handle_inferior_event() functions. This is used only in case of
 186        'step n' like commands.  */
 187     INF_EXEC_CONTINUE
 188   };
 189 \f
 190 /* Target objects which can be transfered using target_read,
 191    target_write, et cetera.  */
 192
 193 enum target_object
 194 {
 195   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 196   TARGET_OBJECT_AVR,
 197   /* SPU target specific transfer.  See "spu-tdep.c".  */
 198   TARGET_OBJECT_SPU,
 199   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 200   TARGET_OBJECT_MEMORY,
 201   /* Memory, avoiding GDB's data cache and trusting the executable.
 202      Target implementations of to_xfer_partial never need to handle
 203      this object, and most callers should not use it.  */
 204   TARGET_OBJECT_RAW_MEMORY,
 205   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 206   TARGET_OBJECT_UNWIND_TABLE,
 207   /* Transfer auxilliary vector.  */
 208   TARGET_OBJECT_AUXV,
 209   /* StackGhost cookie.  See "sparc-tdep.c".  */
 210   TARGET_OBJECT_WCOOKIE,
 211   /* Target memory map in XML format.  */
 212   TARGET_OBJECT_MEMORY_MAP,
 213   /* Flash memory.  This object can be used to write contents to
 214      a previously erased flash memory.  Using it without erasing
 215      flash can have unexpected results.  Addresses are physical
 216      address on target, and not relative to flash start.  */
 217   TARGET_OBJECT_FLASH,
 218   /* Available target-specific features, e.g. registers and coprocessors.
 219      See "target-descriptions.c".  ANNEX should never be empty.  */
 220   TARGET_OBJECT_AVAILABLE_FEATURES,
 221   /* Currently loaded libraries, in XML format.  */
 222   TARGET_OBJECT_LIBRARIES,
 223   /* Get OS specific data.  The ANNEX specifies the type (running
 224      processes, etc.).  */
 225   TARGET_OBJECT_OSDATA,
 226   /* Extra signal info.  Usually the contents of `siginfo_t' on unix
 227      platforms.  */
 228   TARGET_OBJECT_SIGNAL_INFO,
 229   /* Possible future objects: TARGET_OBJECT_FILE, ... */
 230 };
 231
 232 /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 233    OBJECT.  The OFFSET, for a seekable object, specifies the
 234    starting point.  The ANNEX can be used to provide additional
 235    data-specific information to the target.
 236
 237    Return the number of bytes actually transfered, or -1 if the
 238    transfer is not supported or otherwise fails.  Return of a positive
 239    value less than LEN indicates that no further transfer is possible.
 240    Unlike the raw to_xfer_partial interface, callers of these
 241    functions do not need to retry partial transfers.  */
 242
 243 extern LONGEST target_read (struct target_ops *ops,
 244                             enum target_object object,
 245                             const char *annex, gdb_byte *buf,
 246                             ULONGEST offset, LONGEST len);
 247
 248 extern LONGEST target_read_until_error (struct target_ops *ops,
 249                                         enum target_object object,
 250                                         const char *annex, gdb_byte *buf,
 251                                         ULONGEST offset, LONGEST len);
 252
 253 extern LONGEST target_write (struct target_ops *ops,
 254                              enum target_object object,
 255                              const char *annex, const gdb_byte *buf,
 256                              ULONGEST offset, LONGEST len);
 257
 258 /* Similar to target_write, except that it also calls PROGRESS with
 259    the number of bytes written and the opaque BATON after every
 260    successful partial write (and before the first write).  This is
 261    useful for progress reporting and user interaction while writing
 262    data.  To abort the transfer, the progress callback can throw an
 263    exception.  */
 264
 265 LONGEST target_write_with_progress (struct target_ops *ops,
 266                                     enum target_object object,
 267                                     const char *annex, const gdb_byte *buf,
 268                                     ULONGEST offset, LONGEST len,
 269                                     void (*progress) (ULONGEST, void *),
 270                                     void *baton);
 271
 272 /* Wrapper to perform a full read of unknown size.  OBJECT/ANNEX will
 273    be read using OPS.  The return value will be -1 if the transfer
 274    fails or is not supported; 0 if the object is empty; or the length
 275    of the object otherwise.  If a positive value is returned, a
 276    sufficiently large buffer will be allocated using xmalloc and
 277    returned in *BUF_P containing the contents of the object.
 278
 279    This method should be used for objects sufficiently small to store
 280    in a single xmalloc'd buffer, when no fixed bound on the object's
 281    size is known in advance.  Don't try to read TARGET_OBJECT_MEMORY
 282    through this function.  */
 283
 284 extern LONGEST target_read_alloc (struct target_ops *ops,
 285                                   enum target_object object,
 286                                   const char *annex, gdb_byte **buf_p);
 287
 288 /* Read OBJECT/ANNEX using OPS.  The result is NUL-terminated and
 289    returned as a string, allocated using xmalloc.  If an error occurs
 290    or the transfer is unsupported, NULL is returned.  Empty objects
 291    are returned as allocated but empty strings.  A warning is issued
 292    if the result contains any embedded NUL bytes.  */
 293
 294 extern char *target_read_stralloc (struct target_ops *ops,
 295                                    enum target_object object,
 296                                    const char *annex);
 297
 298 /* Wrappers to target read/write that perform memory transfers.  They
 299    throw an error if the memory transfer fails.
 300
 301    NOTE: cagney/2003-10-23: The naming schema is lifted from
 302    "frame.h".  The parameter order is lifted from get_frame_memory,
 303    which in turn lifted it from read_memory.  */
 304
 305 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 306                                gdb_byte *buf, LONGEST len);
 307 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 308                                             CORE_ADDR addr, int len);
 309 \f
 310 struct thread_info;             /* fwd decl for parameter list below: */
 311
 312 struct target_ops
 313   {
 314     struct target_ops *beneath; /* To the target under this one.  */
 315     char *to_shortname;         /* Name this target type */
 316     char *to_longname;          /* Name for printing */
 317     char *to_doc;               /* Documentation.  Does not include trailing
 318                                    newline, and starts with a one-line descrip-
 319                                    tion (probably similar to to_longname).  */
 320     /* Per-target scratch pad.  */
 321     void *to_data;
 322     /* The open routine takes the rest of the parameters from the
 323        command, and (if successful) pushes a new target onto the
 324        stack.  Targets should supply this routine, if only to provide
 325        an error message.  */
 326     void (*to_open) (char *, int);
 327     /* Old targets with a static target vector provide "to_close".
 328        New re-entrant targets provide "to_xclose" and that is expected
 329        to xfree everything (including the "struct target_ops").  */
 330     void (*to_xclose) (struct target_ops *targ, int quitting);
 331     void (*to_close) (int);
 332     void (*to_attach) (struct target_ops *ops, char *, int);
 333     void (*to_post_attach) (int);
 334     void (*to_detach) (struct target_ops *ops, char *, int);
 335     void (*to_disconnect) (struct target_ops *, char *, int);
 336     void (*to_resume) (struct target_ops *, ptid_t, int, enum target_signal);
 337     ptid_t (*to_wait) (struct target_ops *,
 338                        ptid_t, struct target_waitstatus *, int);
 339     void (*to_fetch_registers) (struct target_ops *, struct regcache *, int);
 340     void (*to_store_registers) (struct target_ops *, struct regcache *, int);
 341     void (*to_prepare_to_store) (struct regcache *);
 342
 343     /* Transfer LEN bytes of memory between GDB address MYADDR and
 344        target address MEMADDR.  If WRITE, transfer them to the target, else
 345        transfer them from the target.  TARGET is the target from which we
 346        get this function.
 347
 348        Return value, N, is one of the following:
 349
 350        0 means that we can't handle this.  If errno has been set, it is the
 351        error which prevented us from doing it (FIXME: What about bfd_error?).
 352
 353        positive (call it N) means that we have transferred N bytes
 354        starting at MEMADDR.  We might be able to handle more bytes
 355        beyond this length, but no promises.
 356
 357        negative (call its absolute value N) means that we cannot
 358        transfer right at MEMADDR, but we could transfer at least
 359        something at MEMADDR + N.
 360
 361        NOTE: cagney/2004-10-01: This has been entirely superseeded by
 362        to_xfer_partial and inferior inheritance.  */
 363
 364     int (*deprecated_xfer_memory) (CORE_ADDR memaddr, gdb_byte *myaddr,
 365                                    int len, int write,
 366                                    struct mem_attrib *attrib,
 367                                    struct target_ops *target);
 368
 369     void (*to_files_info) (struct target_ops *);
 370     int (*to_insert_breakpoint) (struct bp_target_info *);
 371     int (*to_remove_breakpoint) (struct bp_target_info *);
 372     int (*to_can_use_hw_breakpoint) (int, int, int);
 373     int (*to_insert_hw_breakpoint) (struct bp_target_info *);
 374     int (*to_remove_hw_breakpoint) (struct bp_target_info *);
 375     int (*to_remove_watchpoint) (CORE_ADDR, int, int);
 376     int (*to_insert_watchpoint) (CORE_ADDR, int, int);
 377     int (*to_stopped_by_watchpoint) (void);
 378     int to_have_steppable_watchpoint;
 379     int to_have_continuable_watchpoint;
 380     int (*to_stopped_data_address) (struct target_ops *, CORE_ADDR *);
 381     int (*to_watchpoint_addr_within_range) (struct target_ops *,
 382                                             CORE_ADDR, CORE_ADDR, int);
 383     int (*to_region_ok_for_hw_watchpoint) (CORE_ADDR, int);
 384     void (*to_terminal_init) (void);
 385     void (*to_terminal_inferior) (void);
 386     void (*to_terminal_ours_for_output) (void);
 387     void (*to_terminal_ours) (void);
 388     void (*to_terminal_save_ours) (void);
 389     void (*to_terminal_info) (char *, int);
 390     void (*to_kill) (struct target_ops *);
 391     void (*to_load) (char *, int);
 392     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 393     void (*to_create_inferior) (struct target_ops *,
 394                                 char *, char *, char **, int);
 395     void (*to_post_startup_inferior) (ptid_t);
 396     void (*to_acknowledge_created_inferior) (int);
 397     void (*to_insert_fork_catchpoint) (int);
 398     int (*to_remove_fork_catchpoint) (int);
 399     void (*to_insert_vfork_catchpoint) (int);
 400     int (*to_remove_vfork_catchpoint) (int);
 401     int (*to_follow_fork) (struct target_ops *, int);
 402     void (*to_insert_exec_catchpoint) (int);
 403     int (*to_remove_exec_catchpoint) (int);
 404     int (*to_has_exited) (int, int, int *);
 405     void (*to_mourn_inferior) (struct target_ops *);
 406     int (*to_can_run) (void);
 407     void (*to_notice_signals) (ptid_t ptid);
 408     int (*to_thread_alive) (struct target_ops *, ptid_t ptid);
 409     void (*to_find_new_threads) (struct target_ops *);
 410     char *(*to_pid_to_str) (struct target_ops *, ptid_t);
 411     char *(*to_extra_thread_info) (struct thread_info *);
 412     void (*to_stop) (ptid_t);
 413     void (*to_rcmd) (char *command, struct ui_file *output);
 414     char *(*to_pid_to_exec_file) (int pid);
 415     void (*to_log_command) (const char *);
 416     struct target_section_table *(*to_get_section_table) (struct target_ops *);
 417     enum strata to_stratum;
 418     int (*to_has_all_memory) (struct target_ops *);
 419     int (*to_has_memory) (struct target_ops *);
 420     int (*to_has_stack) (struct target_ops *);
 421     int (*to_has_registers) (struct target_ops *);
 422     int (*to_has_execution) (struct target_ops *);
 423     int to_has_thread_control;  /* control thread execution */
 424     int to_attach_no_wait;
 425     /* ASYNC target controls */
 426     int (*to_can_async_p) (void);
 427     int (*to_is_async_p) (void);
 428     void (*to_async) (void (*) (enum inferior_event_type, void *), void *);
 429     int (*to_async_mask) (int);
 430     int (*to_supports_non_stop) (void);
 431     int (*to_find_memory_regions) (int (*) (CORE_ADDR,
 432                                             unsigned long,
 433                                             int, int, int,
 434                                             void *),
 435                                    void *);
 436     char * (*to_make_corefile_notes) (bfd *, int *);
 437
 438     /* Return the thread-local address at OFFSET in the
 439        thread-local storage for the thread PTID and the shared library
 440        or executable file given by OBJFILE.  If that block of
 441        thread-local storage hasn't been allocated yet, this function
 442        may return an error.  */
 443     CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
 444                                               ptid_t ptid,
 445                                               CORE_ADDR load_module_addr,
 446                                               CORE_ADDR offset);
 447
 448     /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 449        OBJECT.  The OFFSET, for a seekable object, specifies the
 450        starting point.  The ANNEX can be used to provide additional
 451        data-specific information to the target.
 452
 453        Return the number of bytes actually transfered, zero when no
 454        further transfer is possible, and -1 when the transfer is not
 455        supported.  Return of a positive value smaller than LEN does
 456        not indicate the end of the object, only the end of the
 457        transfer; higher level code should continue transferring if
 458        desired.  This is handled in target.c.
 459
 460        The interface does not support a "retry" mechanism.  Instead it
 461        assumes that at least one byte will be transfered on each
 462        successful call.
 463
 464        NOTE: cagney/2003-10-17: The current interface can lead to
 465        fragmented transfers.  Lower target levels should not implement
 466        hacks, such as enlarging the transfer, in an attempt to
 467        compensate for this.  Instead, the target stack should be
 468        extended so that it implements supply/collect methods and a
 469        look-aside object cache.  With that available, the lowest
 470        target can safely and freely "push" data up the stack.
 471
 472        See target_read and target_write for more information.  One,
 473        and only one, of readbuf or writebuf must be non-NULL.  */
 474
 475     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 476                                 enum target_object object, const char *annex,
 477                                 gdb_byte *readbuf, const gdb_byte *writebuf,
 478                                 ULONGEST offset, LONGEST len);
 479
 480     /* Returns the memory map for the target.  A return value of NULL
 481        means that no memory map is available.  If a memory address
 482        does not fall within any returned regions, it's assumed to be
 483        RAM.  The returned memory regions should not overlap.
 484
 485        The order of regions does not matter; target_memory_map will
 486        sort regions by starting address. For that reason, this
 487        function should not be called directly except via
 488        target_memory_map.
 489
 490        This method should not cache data; if the memory map could
 491        change unexpectedly, it should be invalidated, and higher
 492        layers will re-fetch it.  */
 493     VEC(mem_region_s) *(*to_memory_map) (struct target_ops *);
 494
 495     /* Erases the region of flash memory starting at ADDRESS, of
 496        length LENGTH.
 497
 498        Precondition: both ADDRESS and ADDRESS+LENGTH should be aligned
 499        on flash block boundaries, as reported by 'to_memory_map'.  */
 500     void (*to_flash_erase) (struct target_ops *,
 501                            ULONGEST address, LONGEST length);
 502
 503     /* Finishes a flash memory write sequence.  After this operation
 504        all flash memory should be available for writing and the result
 505        of reading from areas written by 'to_flash_write' should be
 506        equal to what was written.  */
 507     void (*to_flash_done) (struct target_ops *);
 508
 509     /* Describe the architecture-specific features of this target.
 510        Returns the description found, or NULL if no description
 511        was available.  */
 512     const struct target_desc *(*to_read_description) (struct target_ops *ops);
 513
 514     /* Build the PTID of the thread on which a given task is running,
 515        based on LWP and THREAD.  These values are extracted from the
 516        task Private_Data section of the Ada Task Control Block, and
 517        their interpretation depends on the target.  */
 518     ptid_t (*to_get_ada_task_ptid) (long lwp, long thread);
 519
 520     /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
 521        Return 0 if *READPTR is already at the end of the buffer.
 522        Return -1 if there is insufficient buffer for a whole entry.
 523        Return 1 if an entry was read into *TYPEP and *VALP.  */
 524     int (*to_auxv_parse) (struct target_ops *ops, gdb_byte **readptr,
 525                          gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 526
 527     /* Search SEARCH_SPACE_LEN bytes beginning at START_ADDR for the
 528        sequence of bytes in PATTERN with length PATTERN_LEN.
 529
 530        The result is 1 if found, 0 if not found, and -1 if there was an error
 531        requiring halting of the search (e.g. memory read error).
 532        If the pattern is found the address is recorded in FOUND_ADDRP.  */
 533     int (*to_search_memory) (struct target_ops *ops,
 534                              CORE_ADDR start_addr, ULONGEST search_space_len,
 535                              const gdb_byte *pattern, ULONGEST pattern_len,
 536                              CORE_ADDR *found_addrp);
 537
 538     /* Can target execute in reverse?  */
 539     int (*to_can_execute_reverse) (void);
 540
 541     /* Does this target support debugging multiple processes
 542        simultaneously?  */
 543     int (*to_supports_multi_process) (void);
 544
 545     int to_magic;
 546     /* Need sub-structure for target machine related rather than comm related?
 547      */
 548   };
 549
 550 /* Magic number for checking ops size.  If a struct doesn't end with this
 551    number, somebody changed the declaration but didn't change all the
 552    places that initialize one.  */
 553
 554 #define OPS_MAGIC       3840
 555
 556 /* The ops structure for our "current" target process.  This should
 557    never be NULL.  If there is no target, it points to the dummy_target.  */
 558
 559 extern struct target_ops current_target;
 560
 561 /* Define easy words for doing these operations on our current target.  */
 562
 563 #define target_shortname        (current_target.to_shortname)
 564 #define target_longname         (current_target.to_longname)
 565
 566 /* Does whatever cleanup is required for a target that we are no
 567    longer going to be calling.  QUITTING indicates that GDB is exiting
 568    and should not get hung on an error (otherwise it is important to
 569    perform clean termination, even if it takes a while).  This routine
 570    is automatically always called when popping the target off the
 571    target stack (to_beneath is undefined).  Closing file descriptors
 572    and freeing all memory allocated memory are typical things it
 573    should do.  */
 574
 575 void target_close (struct target_ops *targ, int quitting);
 576
 577 /* Attaches to a process on the target side.  Arguments are as passed
 578    to the `attach' command by the user.  This routine can be called
 579    when the target is not on the target-stack, if the target_can_run
 580    routine returns 1; in that case, it must push itself onto the stack.
 581    Upon exit, the target should be ready for normal operations, and
 582    should be ready to deliver the status of the process immediately
 583    (without waiting) to an upcoming target_wait call.  */
 584
 585 void target_attach (char *, int);
 586
 587 /* Some targets don't generate traps when attaching to the inferior,
 588    or their target_attach implementation takes care of the waiting.
 589    These targets must set to_attach_no_wait.  */
 590
 591 #define target_attach_no_wait \
 592      (current_target.to_attach_no_wait)
 593
 594 /* The target_attach operation places a process under debugger control,
 595    and stops the process.
 596
 597    This operation provides a target-specific hook that allows the
 598    necessary bookkeeping to be performed after an attach completes.  */
 599 #define target_post_attach(pid) \
 600      (*current_target.to_post_attach) (pid)
 601
 602 /* Takes a program previously attached to and detaches it.
 603    The program may resume execution (some targets do, some don't) and will
 604    no longer stop on signals, etc.  We better not have left any breakpoints
 605    in the program or it'll die when it hits one.  ARGS is arguments
 606    typed by the user (e.g. a signal to send the process).  FROM_TTY
 607    says whether to be verbose or not.  */
 608
 609 extern void target_detach (char *, int);
 610
 611 /* Disconnect from the current target without resuming it (leaving it
 612    waiting for a debugger).  */
 613
 614 extern void target_disconnect (char *, int);
 615
 616 /* Resume execution of the target process PTID.  STEP says whether to
 617    single-step or to run free; SIGGNAL is the signal to be given to
 618    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 619    pass TARGET_SIGNAL_DEFAULT.  */
 620
 621 extern void target_resume (ptid_t ptid, int step, enum target_signal signal);
 622
 623 /* Wait for process pid to do something.  PTID = -1 to wait for any
 624    pid to do something.  Return pid of child, or -1 in case of error;
 625    store status through argument pointer STATUS.  Note that it is
 626    _NOT_ OK to throw_exception() out of target_wait() without popping
 627    the debugging target from the stack; GDB isn't prepared to get back
 628    to the prompt with a debugging target but without the frame cache,
 629    stop_pc, etc., set up.  OPTIONS is a bitwise OR of TARGET_W*
 630    options.  */
 631
 632 extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status,
 633                            int options);
 634
 635 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 636
 637 extern void target_fetch_registers (struct regcache *regcache, int regno);
 638
 639 /* Store at least register REGNO, or all regs if REGNO == -1.
 640    It can store as many registers as it wants to, so target_prepare_to_store
 641    must have been previously called.  Calls error() if there are problems.  */
 642
 643 extern void target_store_registers (struct regcache *regcache, int regs);
 644
 645 /* Get ready to modify the registers array.  On machines which store
 646    individual registers, this doesn't need to do anything.  On machines
 647    which store all the registers in one fell swoop, this makes sure
 648    that REGISTERS contains all the registers from the program being
 649    debugged.  */
 650
 651 #define target_prepare_to_store(regcache)       \
 652      (*current_target.to_prepare_to_store) (regcache)
 653
 654 /* Returns true if this target can debug multiple processes
 655    simultaneously.  */
 656
 657 #define target_supports_multi_process() \
 658      (*current_target.to_supports_multi_process) ()
 659
 660 extern DCACHE *target_dcache;
 661
 662 extern int target_read_string (CORE_ADDR, char **, int, int *);
 663
 664 extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 665
 666 extern int target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 667                                 int len);
 668
 669 /* Fetches the target's memory map.  If one is found it is sorted
 670    and returned, after some consistency checking.  Otherwise, NULL
 671    is returned.  */
 672 VEC(mem_region_s) *target_memory_map (void);
 673
 674 /* Erase the specified flash region.  */
 675 void target_flash_erase (ULONGEST address, LONGEST length);
 676
 677 /* Finish a sequence of flash operations.  */
 678 void target_flash_done (void);
 679
 680 /* Describes a request for a memory write operation.  */
 681 struct memory_write_request
 682   {
 683     /* Begining address that must be written. */
 684     ULONGEST begin;
 685     /* Past-the-end address. */
 686     ULONGEST end;
 687     /* The data to write. */
 688     gdb_byte *data;
 689     /* A callback baton for progress reporting for this request.  */
 690     void *baton;
 691   };
 692 typedef struct memory_write_request memory_write_request_s;
 693 DEF_VEC_O(memory_write_request_s);
 694
 695 /* Enumeration specifying different flash preservation behaviour.  */
 696 enum flash_preserve_mode
 697   {
 698     flash_preserve,
 699     flash_discard
 700   };
 701
 702 /* Write several memory blocks at once.  This version can be more
 703    efficient than making several calls to target_write_memory, in
 704    particular because it can optimize accesses to flash memory.
 705
 706    Moreover, this is currently the only memory access function in gdb
 707    that supports writing to flash memory, and it should be used for
 708    all cases where access to flash memory is desirable.
 709
 710    REQUESTS is the vector (see vec.h) of memory_write_request.
 711    PRESERVE_FLASH_P indicates what to do with blocks which must be
 712      erased, but not completely rewritten.
 713    PROGRESS_CB is a function that will be periodically called to provide
 714      feedback to user.  It will be called with the baton corresponding
 715      to the request currently being written.  It may also be called
 716      with a NULL baton, when preserved flash sectors are being rewritten.
 717
 718    The function returns 0 on success, and error otherwise.  */
 719 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 720                                 enum flash_preserve_mode preserve_flash_p,
 721                                 void (*progress_cb) (ULONGEST, void *));
 722
 723 /* From infrun.c.  */
 724
 725 extern int inferior_has_forked (ptid_t pid, ptid_t *child_pid);
 726
 727 extern int inferior_has_vforked (ptid_t pid, ptid_t *child_pid);
 728
 729 extern int inferior_has_execd (ptid_t pid, char **execd_pathname);
 730
 731 /* Print a line about the current target.  */
 732
 733 #define target_files_info()     \
 734      (*current_target.to_files_info) (&current_target)
 735
 736 /* Insert a breakpoint at address BP_TGT->placed_address in the target
 737    machine.  Result is 0 for success, or an errno value.  */
 738
 739 #define target_insert_breakpoint(bp_tgt)        \
 740      (*current_target.to_insert_breakpoint) (bp_tgt)
 741
 742 /* Remove a breakpoint at address BP_TGT->placed_address in the target
 743    machine.  Result is 0 for success, or an errno value.  */
 744
 745 #define target_remove_breakpoint(bp_tgt)        \
 746      (*current_target.to_remove_breakpoint) (bp_tgt)
 747
 748 /* Initialize the terminal settings we record for the inferior,
 749    before we actually run the inferior.  */
 750
 751 #define target_terminal_init() \
 752      (*current_target.to_terminal_init) ()
 753
 754 /* Put the inferior's terminal settings into effect.
 755    This is preparation for starting or resuming the inferior.  */
 756
 757 extern void target_terminal_inferior (void);
 758
 759 /* Put some of our terminal settings into effect,
 760    enough to get proper results from our output,
 761    but do not change into or out of RAW mode
 762    so that no input is discarded.
 763
 764    After doing this, either terminal_ours or terminal_inferior
 765    should be called to get back to a normal state of affairs.  */
 766
 767 #define target_terminal_ours_for_output() \
 768      (*current_target.to_terminal_ours_for_output) ()
 769
 770 /* Put our terminal settings into effect.
 771    First record the inferior's terminal settings
 772    so they can be restored properly later.  */
 773
 774 #define target_terminal_ours() \
 775      (*current_target.to_terminal_ours) ()
 776
 777 /* Save our terminal settings.
 778    This is called from TUI after entering or leaving the curses
 779    mode.  Since curses modifies our terminal this call is here
 780    to take this change into account.  */
 781
 782 #define target_terminal_save_ours() \
 783      (*current_target.to_terminal_save_ours) ()
 784
 785 /* Print useful information about our terminal status, if such a thing
 786    exists.  */
 787
 788 #define target_terminal_info(arg, from_tty) \
 789      (*current_target.to_terminal_info) (arg, from_tty)
 790
 791 /* Kill the inferior process.   Make it go away.  */
 792
 793 extern void target_kill (void);
 794
 795 /* Load an executable file into the target process.  This is expected
 796    to not only bring new code into the target process, but also to
 797    update GDB's symbol tables to match.
 798
 799    ARG contains command-line arguments, to be broken down with
 800    buildargv ().  The first non-switch argument is the filename to
 801    load, FILE; the second is a number (as parsed by strtoul (..., ...,
 802    0)), which is an offset to apply to the load addresses of FILE's
 803    sections.  The target may define switches, or other non-switch
 804    arguments, as it pleases.  */
 805
 806 extern void target_load (char *arg, int from_tty);
 807
 808 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 809    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 810    symbol should be returned.  The result is 0 if successful, nonzero
 811    if the symbol does not exist in the target environment.  This
 812    function should not call error() if communication with the target
 813    is interrupted, since it is called from symbol reading, but should
 814    return nonzero, possibly doing a complain().  */
 815
 816 #define target_lookup_symbol(name, addrp) \
 817      (*current_target.to_lookup_symbol) (name, addrp)
 818
 819 /* Start an inferior process and set inferior_ptid to its pid.
 820    EXEC_FILE is the file to run.
 821    ALLARGS is a string containing the arguments to the program.
 822    ENV is the environment vector to pass.  Errors reported with error().
 823    On VxWorks and various standalone systems, we ignore exec_file.  */
 824
 825 void target_create_inferior (char *exec_file, char *args,
 826                              char **env, int from_tty);
 827
 828 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 829    notification of inferior events such as fork and vork immediately
 830    after the inferior is created.  (This because of how gdb gets an
 831    inferior created via invoking a shell to do it.  In such a scenario,
 832    if the shell init file has commands in it, the shell will fork and
 833    exec for each of those commands, and we will see each such fork
 834    event.  Very bad.)
 835
 836    Such targets will supply an appropriate definition for this function.  */
 837
 838 #define target_post_startup_inferior(ptid) \
 839      (*current_target.to_post_startup_inferior) (ptid)
 840
 841 /* On some targets, the sequence of starting up an inferior requires
 842    some synchronization between gdb and the new inferior process, PID.  */
 843
 844 #define target_acknowledge_created_inferior(pid) \
 845      (*current_target.to_acknowledge_created_inferior) (pid)
 846
 847 /* On some targets, we can catch an inferior fork or vfork event when
 848    it occurs.  These functions insert/remove an already-created
 849    catchpoint for such events.  */
 850
 851 #define target_insert_fork_catchpoint(pid) \
 852      (*current_target.to_insert_fork_catchpoint) (pid)
 853
 854 #define target_remove_fork_catchpoint(pid) \
 855      (*current_target.to_remove_fork_catchpoint) (pid)
 856
 857 #define target_insert_vfork_catchpoint(pid) \
 858      (*current_target.to_insert_vfork_catchpoint) (pid)
 859
 860 #define target_remove_vfork_catchpoint(pid) \
 861      (*current_target.to_remove_vfork_catchpoint) (pid)
 862
 863 /* If the inferior forks or vforks, this function will be called at
 864    the next resume in order to perform any bookkeeping and fiddling
 865    necessary to continue debugging either the parent or child, as
 866    requested, and releasing the other.  Information about the fork
 867    or vfork event is available via get_last_target_status ().
 868    This function returns 1 if the inferior should not be resumed
 869    (i.e. there is another event pending).  */
 870
 871 int target_follow_fork (int follow_child);
 872
 873 /* On some targets, we can catch an inferior exec event when it
 874    occurs.  These functions insert/remove an already-created
 875    catchpoint for such events.  */
 876
 877 #define target_insert_exec_catchpoint(pid) \
 878      (*current_target.to_insert_exec_catchpoint) (pid)
 879
 880 #define target_remove_exec_catchpoint(pid) \
 881      (*current_target.to_remove_exec_catchpoint) (pid)
 882
 883 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 884    exit code of PID, if any.  */
 885
 886 #define target_has_exited(pid,wait_status,exit_status) \
 887      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 888
 889 /* The debugger has completed a blocking wait() call.  There is now
 890    some process event that must be processed.  This function should
 891    be defined by those targets that require the debugger to perform
 892    cleanup or internal state changes in response to the process event.  */
 893
 894 /* The inferior process has died.  Do what is right.  */
 895
 896 void target_mourn_inferior (void);
 897
 898 /* Does target have enough data to do a run or attach command? */
 899
 900 #define target_can_run(t) \
 901      ((t)->to_can_run) ()
 902
 903 /* post process changes to signal handling in the inferior.  */
 904
 905 #define target_notice_signals(ptid) \
 906      (*current_target.to_notice_signals) (ptid)
 907
 908 /* Check to see if a thread is still alive.  */
 909
 910 extern int target_thread_alive (ptid_t ptid);
 911
 912 /* Query for new threads and add them to the thread list.  */
 913
 914 extern void target_find_new_threads (void);
 915
 916 /* Make target stop in a continuable fashion.  (For instance, under
 917    Unix, this should act like SIGSTOP).  This function is normally
 918    used by GUIs to implement a stop button.  */
 919
 920 #define target_stop(ptid) (*current_target.to_stop) (ptid)
 921
 922 /* Send the specified COMMAND to the target's monitor
 923    (shell,interpreter) for execution.  The result of the query is
 924    placed in OUTBUF.  */
 925
 926 #define target_rcmd(command, outbuf) \
 927      (*current_target.to_rcmd) (command, outbuf)
 928
 929
 930 /* Does the target include all of memory, or only part of it?  This
 931    determines whether we look up the target chain for other parts of
 932    memory if this target can't satisfy a request.  */
 933
 934 extern int target_has_all_memory_1 (void);
 935 #define target_has_all_memory target_has_all_memory_1 ()
 936
 937 /* Does the target include memory?  (Dummy targets don't.)  */
 938
 939 extern int target_has_memory_1 (void);
 940 #define target_has_memory target_has_memory_1 ()
 941
 942 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 943    we start a process.)  */
 944
 945 extern int target_has_stack_1 (void);
 946 #define target_has_stack target_has_stack_1 ()
 947
 948 /* Does the target have registers?  (Exec files don't.)  */
 949
 950 extern int target_has_registers_1 (void);
 951 #define target_has_registers target_has_registers_1 ()
 952
 953 /* Does the target have execution?  Can we make it jump (through
 954    hoops), or pop its stack a few times?  This means that the current
 955    target is currently executing; for some targets, that's the same as
 956    whether or not the target is capable of execution, but there are
 957    also targets which can be current while not executing.  In that
 958    case this will become true after target_create_inferior or
 959    target_attach.  */
 960
 961 extern int target_has_execution_1 (void);
 962 #define target_has_execution target_has_execution_1 ()
 963
 964 /* Default implementations for process_stratum targets.  Return true
 965    if there's a selected inferior, false otherwise.  */
 966
 967 extern int default_child_has_all_memory (struct target_ops *ops);
 968 extern int default_child_has_memory (struct target_ops *ops);
 969 extern int default_child_has_stack (struct target_ops *ops);
 970 extern int default_child_has_registers (struct target_ops *ops);
 971 extern int default_child_has_execution (struct target_ops *ops);
 972
 973 /* Can the target support the debugger control of thread execution?
 974    Can it lock the thread scheduler?  */
 975
 976 #define target_can_lock_scheduler \
 977      (current_target.to_has_thread_control & tc_schedlock)
 978
 979 /* Should the target enable async mode if it is supported?  Temporary
 980    cludge until async mode is a strict superset of sync mode.  */
 981 extern int target_async_permitted;
 982
 983 /* Can the target support asynchronous execution? */
 984 #define target_can_async_p() (current_target.to_can_async_p ())
 985
 986 /* Is the target in asynchronous execution mode? */
 987 #define target_is_async_p() (current_target.to_is_async_p ())
 988
 989 int target_supports_non_stop (void);
 990
 991 /* Put the target in async mode with the specified callback function. */
 992 #define target_async(CALLBACK,CONTEXT) \
 993      (current_target.to_async ((CALLBACK), (CONTEXT)))
 994
 995 /* This is to be used ONLY within call_function_by_hand(). It provides
 996    a workaround, to have inferior function calls done in sychronous
 997    mode, even though the target is asynchronous. After
 998    target_async_mask(0) is called, calls to target_can_async_p() will
 999    return FALSE , so that target_resume() will not try to start the
1000    target asynchronously. After the inferior stops, we IMMEDIATELY
1001    restore the previous nature of the target, by calling
1002    target_async_mask(1). After that, target_can_async_p() will return
1003    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
1004
1005    FIXME ezannoni 1999-12-13: we won't need this once we move
1006    the turning async on and off to the single execution commands,
1007    from where it is done currently, in remote_resume().  */
1008
1009 #define target_async_mask(MASK) \
1010   (current_target.to_async_mask (MASK))
1011
1012 /* Converts a process id to a string.  Usually, the string just contains
1013    `process xyz', but on some systems it may contain
1014    `process xyz thread abc'.  */
1015
1016 extern char *target_pid_to_str (ptid_t ptid);
1017
1018 extern char *normal_pid_to_str (ptid_t ptid);
1019
1020 /* Return a short string describing extra information about PID,
1021    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1022    is okay.  */
1023
1024 #define target_extra_thread_info(TP) \
1025      (current_target.to_extra_thread_info (TP))
1026
1027 /* Attempts to find the pathname of the executable file
1028    that was run to create a specified process.
1029
1030    The process PID must be stopped when this operation is used.
1031
1032    If the executable file cannot be determined, NULL is returned.
1033
1034    Else, a pointer to a character string containing the pathname
1035    is returned.  This string should be copied into a buffer by
1036    the client if the string will not be immediately used, or if
1037    it must persist.  */
1038
1039 #define target_pid_to_exec_file(pid) \
1040      (current_target.to_pid_to_exec_file) (pid)
1041
1042 /*
1043  * Iterator function for target memory regions.
1044  * Calls a callback function once for each memory region 'mapped'
1045  * in the child process.  Defined as a simple macro rather than
1046  * as a function macro so that it can be tested for nullity.
1047  */
1048
1049 #define target_find_memory_regions(FUNC, DATA) \
1050      (current_target.to_find_memory_regions) (FUNC, DATA)
1051
1052 /*
1053  * Compose corefile .note section.
1054  */
1055
1056 #define target_make_corefile_notes(BFD, SIZE_P) \
1057      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
1058
1059 /* Hardware watchpoint interfaces.  */
1060
1061 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1062    write).  */
1063
1064 #define target_stopped_by_watchpoint \
1065    (*current_target.to_stopped_by_watchpoint)
1066
1067 /* Non-zero if we have steppable watchpoints  */
1068
1069 #define target_have_steppable_watchpoint \
1070    (current_target.to_have_steppable_watchpoint)
1071
1072 /* Non-zero if we have continuable watchpoints  */
1073
1074 #define target_have_continuable_watchpoint \
1075    (current_target.to_have_continuable_watchpoint)
1076
1077 /* Provide defaults for hardware watchpoint functions.  */
1078
1079 /* If the *_hw_beakpoint functions have not been defined
1080    elsewhere use the definitions in the target vector.  */
1081
1082 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1083    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1084    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1085    (including this one?).  OTHERTYPE is who knows what...  */
1086
1087 #define target_can_use_hardware_watchpoint(TYPE,CNT,OTHERTYPE) \
1088  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1089
1090 #define target_region_ok_for_hw_watchpoint(addr, len) \
1091     (*current_target.to_region_ok_for_hw_watchpoint) (addr, len)
1092
1093
1094 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1095    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1096    success, non-zero for failure.  */
1097
1098 #define target_insert_watchpoint(addr, len, type)       \
1099      (*current_target.to_insert_watchpoint) (addr, len, type)
1100
1101 #define target_remove_watchpoint(addr, len, type)       \
1102      (*current_target.to_remove_watchpoint) (addr, len, type)
1103
1104 #define target_insert_hw_breakpoint(bp_tgt) \
1105      (*current_target.to_insert_hw_breakpoint) (bp_tgt)
1106
1107 #define target_remove_hw_breakpoint(bp_tgt) \
1108      (*current_target.to_remove_hw_breakpoint) (bp_tgt)
1109
1110 #define target_stopped_data_address(target, x) \
1111     (*target.to_stopped_data_address) (target, x)
1112
1113 #define target_watchpoint_addr_within_range(target, addr, start, length) \
1114   (*target.to_watchpoint_addr_within_range) (target, addr, start, length)
1115
1116 /* Target can execute in reverse?  */
1117 #define target_can_execute_reverse \
1118      (current_target.to_can_execute_reverse ? \
1119       current_target.to_can_execute_reverse () : 0)
1120
1121 extern const struct target_desc *target_read_description (struct target_ops *);
1122
1123 #define target_get_ada_task_ptid(lwp, tid) \
1124      (*current_target.to_get_ada_task_ptid) (lwp,tid)
1125
1126 /* Utility implementation of searching memory.  */
1127 extern int simple_search_memory (struct target_ops* ops,
1128                                  CORE_ADDR start_addr,
1129                                  ULONGEST search_space_len,
1130                                  const gdb_byte *pattern,
1131                                  ULONGEST pattern_len,
1132                                  CORE_ADDR *found_addrp);
1133
1134 /* Main entry point for searching memory.  */
1135 extern int target_search_memory (CORE_ADDR start_addr,
1136                                  ULONGEST search_space_len,
1137                                  const gdb_byte *pattern,
1138                                  ULONGEST pattern_len,
1139                                  CORE_ADDR *found_addrp);
1140
1141 /* Command logging facility.  */
1142
1143 #define target_log_command(p)                                           \
1144   do                                                                    \
1145     if (current_target.to_log_command)                                  \
1146       (*current_target.to_log_command) (p);                             \
1147   while (0)
1148
1149 /* Routines for maintenance of the target structures...
1150
1151    add_target:   Add a target to the list of all possible targets.
1152
1153    push_target:  Make this target the top of the stack of currently used
1154    targets, within its particular stratum of the stack.  Result
1155    is 0 if now atop the stack, nonzero if not on top (maybe
1156    should warn user).
1157
1158    unpush_target: Remove this from the stack of currently used targets,
1159    no matter where it is on the list.  Returns 0 if no
1160    change, 1 if removed from stack.
1161
1162    pop_target:   Remove the top thing on the stack of current targets.  */
1163
1164 extern void add_target (struct target_ops *);
1165
1166 extern int push_target (struct target_ops *);
1167
1168 extern int unpush_target (struct target_ops *);
1169
1170 extern void target_pre_inferior (int);
1171
1172 extern void target_preopen (int);
1173
1174 extern void pop_target (void);
1175
1176 /* Does whatever cleanup is required to get rid of all pushed targets.
1177    QUITTING is propagated to target_close; it indicates that GDB is
1178    exiting and should not get hung on an error (otherwise it is
1179    important to perform clean termination, even if it takes a
1180    while).  */
1181 extern void pop_all_targets (int quitting);
1182
1183 /* Like pop_all_targets, but pops only targets whose stratum is
1184    strictly above ABOVE_STRATUM.  */
1185 extern void pop_all_targets_above (enum strata above_stratum, int quitting);
1186
1187 extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
1188                                                CORE_ADDR offset);
1189
1190 /* Struct target_section maps address ranges to file sections.  It is
1191    mostly used with BFD files, but can be used without (e.g. for handling
1192    raw disks, or files not in formats handled by BFD).  */
1193
1194 struct target_section
1195   {
1196     CORE_ADDR addr;             /* Lowest address in section */
1197     CORE_ADDR endaddr;          /* 1+highest address in section */
1198
1199     struct bfd_section *the_bfd_section;
1200
1201     bfd *bfd;                   /* BFD file pointer */
1202   };
1203
1204 /* Holds an array of target sections.  Defined by [SECTIONS..SECTIONS_END[.  */
1205
1206 struct target_section_table
1207 {
1208   struct target_section *sections;
1209   struct target_section *sections_end;
1210 };
1211
1212 /* Return the "section" containing the specified address.  */
1213 struct target_section *target_section_by_addr (struct target_ops *target,
1214                                                CORE_ADDR addr);
1215
1216 /* Return the target section table this target (or the targets
1217    beneath) currently manipulate.  */
1218
1219 extern struct target_section_table *target_get_section_table
1220   (struct target_ops *target);
1221
1222 /* From mem-break.c */
1223
1224 extern int memory_remove_breakpoint (struct bp_target_info *);
1225
1226 extern int memory_insert_breakpoint (struct bp_target_info *);
1227
1228 extern int default_memory_remove_breakpoint (struct gdbarch *, struct bp_target_info *);
1229
1230 extern int default_memory_insert_breakpoint (struct gdbarch *, struct bp_target_info *);
1231
1232
1233 /* From target.c */
1234
1235 extern void initialize_targets (void);
1236
1237 extern NORETURN void noprocess (void) ATTR_NORETURN;
1238
1239 extern void target_require_runnable (void);
1240
1241 extern void find_default_attach (struct target_ops *, char *, int);
1242
1243 extern void find_default_create_inferior (struct target_ops *,
1244                                           char *, char *, char **, int);
1245
1246 extern struct target_ops *find_run_target (void);
1247
1248 extern struct target_ops *find_core_target (void);
1249
1250 extern struct target_ops *find_target_beneath (struct target_ops *);
1251
1252 /* Read OS data object of type TYPE from the target, and return it in
1253    XML format.  The result is NUL-terminated and returned as a string,
1254    allocated using xmalloc.  If an error occurs or the transfer is
1255    unsupported, NULL is returned.  Empty objects are returned as
1256    allocated but empty strings.  */
1257
1258 extern char *target_get_osdata (const char *type);
1259
1260 \f
1261 /* Stuff that should be shared among the various remote targets.  */
1262
1263 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1264    information (higher values, more information).  */
1265 extern int remote_debug;
1266
1267 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1268 extern int baud_rate;
1269 /* Timeout limit for response from target. */
1270 extern int remote_timeout;
1271
1272 \f
1273 /* Functions for helping to write a native target.  */
1274
1275 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1276 extern void store_waitstatus (struct target_waitstatus *, int);
1277
1278 /* These are in common/signals.c, but they're only used by gdb.  */
1279 extern enum target_signal default_target_signal_from_host (struct gdbarch *,
1280                                                            int);
1281 extern int default_target_signal_to_host (struct gdbarch *,
1282                                           enum target_signal);
1283
1284 /* Convert from a number used in a GDB command to an enum target_signal.  */
1285 extern enum target_signal target_signal_from_command (int);
1286 /* End of files in common/signals.c.  */
1287
1288 /* Set the show memory breakpoints mode to show, and installs a cleanup
1289    to restore it back to the current value.  */
1290 extern struct cleanup *make_show_memory_breakpoints_cleanup (int show);
1291
1292 \f
1293 /* Imported from machine dependent code */
1294
1295 /* Blank target vector entries are initialized to target_ignore. */
1296 void target_ignore (void);
1297
1298 extern struct target_ops deprecated_child_ops;
1299
1300 #endif /* !defined (TARGET_H) */