gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2
   3    Copyright (C) 1990-2012 Free Software Foundation, Inc.
   4
   5    Contributed by Cygnus Support.  Written by John Gilmore.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #if !defined (TARGET_H)
  23 #define TARGET_H
  24
  25 struct objfile;
  26 struct ui_file;
  27 struct mem_attrib;
  28 struct target_ops;
  29 struct bp_location;
  30 struct bp_target_info;
  31 struct regcache;
  32 struct target_section_table;
  33 struct trace_state_variable;
  34 struct trace_status;
  35 struct uploaded_tsv;
  36 struct uploaded_tp;
  37 struct static_tracepoint_marker;
  38 struct traceframe_info;
  39 struct expression;
  40
  41 /* This include file defines the interface between the main part
  42    of the debugger, and the part which is target-specific, or
  43    specific to the communications interface between us and the
  44    target.
  45
  46    A TARGET is an interface between the debugger and a particular
  47    kind of file or process.  Targets can be STACKED in STRATA,
  48    so that more than one target can potentially respond to a request.
  49    In particular, memory accesses will walk down the stack of targets
  50    until they find a target that is interested in handling that particular
  51    address.  STRATA are artificial boundaries on the stack, within
  52    which particular kinds of targets live.  Strata exist so that
  53    people don't get confused by pushing e.g. a process target and then
  54    a file target, and wondering why they can't see the current values
  55    of variables any more (the file target is handling them and they
  56    never get to the process target).  So when you push a file target,
  57    it goes into the file stratum, which is always below the process
  58    stratum.  */
  59
  60 #include "bfd.h"
  61 #include "symtab.h"
  62 #include "memattr.h"
  63 #include "vec.h"
  64 #include "gdb_signals.h"
  65
  66 enum strata
  67   {
  68     dummy_stratum,              /* The lowest of the low */
  69     file_stratum,               /* Executable files, etc */
  70     process_stratum,            /* Executing processes or core dump files */
  71     thread_stratum,             /* Executing threads */
  72     record_stratum,             /* Support record debugging */
  73     arch_stratum                /* Architecture overrides */
  74   };
  75
  76 enum thread_control_capabilities
  77   {
  78     tc_none = 0,                /* Default: can't control thread execution.  */
  79     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  80   };
  81
  82 /* Stuff for target_wait.  */
  83
  84 /* Generally, what has the program done?  */
  85 enum target_waitkind
  86   {
  87     /* The program has exited.  The exit status is in value.integer.  */
  88     TARGET_WAITKIND_EXITED,
  89
  90     /* The program has stopped with a signal.  Which signal is in
  91        value.sig.  */
  92     TARGET_WAITKIND_STOPPED,
  93
  94     /* The program has terminated with a signal.  Which signal is in
  95        value.sig.  */
  96     TARGET_WAITKIND_SIGNALLED,
  97
  98     /* The program is letting us know that it dynamically loaded something
  99        (e.g. it called load(2) on AIX).  */
 100     TARGET_WAITKIND_LOADED,
 101
 102     /* The program has forked.  A "related" process' PTID is in
 103        value.related_pid.  I.e., if the child forks, value.related_pid
 104        is the parent's ID.  */
 105
 106     TARGET_WAITKIND_FORKED,
 107
 108     /* The program has vforked.  A "related" process's PTID is in
 109        value.related_pid.  */
 110
 111     TARGET_WAITKIND_VFORKED,
 112
 113     /* The program has exec'ed a new executable file.  The new file's
 114        pathname is pointed to by value.execd_pathname.  */
 115
 116     TARGET_WAITKIND_EXECD,
 117
 118     /* The program had previously vforked, and now the child is done
 119        with the shared memory region, because it exec'ed or exited.
 120        Note that the event is reported to the vfork parent.  This is
 121        only used if GDB did not stay attached to the vfork child,
 122        otherwise, a TARGET_WAITKIND_EXECD or
 123        TARGET_WAITKIND_EXIT|SIGNALLED event associated with the child
 124        has the same effect.  */
 125     TARGET_WAITKIND_VFORK_DONE,
 126
 127     /* The program has entered or returned from a system call.  On
 128        HP-UX, this is used in the hardware watchpoint implementation.
 129        The syscall's unique integer ID number is in value.syscall_id.  */
 130
 131     TARGET_WAITKIND_SYSCALL_ENTRY,
 132     TARGET_WAITKIND_SYSCALL_RETURN,
 133
 134     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 135        within target_wait, but I'm not sure target_wait should be resuming the
 136        inferior.  */
 137     TARGET_WAITKIND_SPURIOUS,
 138
 139     /* An event has occured, but we should wait again.
 140        Remote_async_wait() returns this when there is an event
 141        on the inferior, but the rest of the world is not interested in
 142        it.  The inferior has not stopped, but has just sent some output
 143        to the console, for instance.  In this case, we want to go back
 144        to the event loop and wait there for another event from the
 145        inferior, rather than being stuck in the remote_async_wait()
 146        function. sThis way the event loop is responsive to other events,
 147        like for instance the user typing.  */
 148     TARGET_WAITKIND_IGNORE,
 149
 150     /* The target has run out of history information,
 151        and cannot run backward any further.  */
 152     TARGET_WAITKIND_NO_HISTORY,
 153
 154     /* There are no resumed children left in the program.  */
 155     TARGET_WAITKIND_NO_RESUMED
 156   };
 157
 158 struct target_waitstatus
 159   {
 160     enum target_waitkind kind;
 161
 162     /* Forked child pid, execd pathname, exit status, signal number or
 163        syscall number.  */
 164     union
 165       {
 166         int integer;
 167         enum target_signal sig;
 168         ptid_t related_pid;
 169         char *execd_pathname;
 170         int syscall_number;
 171       }
 172     value;
 173   };
 174
 175 /* Options that can be passed to target_wait.  */
 176
 177 /* Return immediately if there's no event already queued.  If this
 178    options is not requested, target_wait blocks waiting for an
 179    event.  */
 180 #define TARGET_WNOHANG 1
 181
 182 /* The structure below stores information about a system call.
 183    It is basically used in the "catch syscall" command, and in
 184    every function that gives information about a system call.
 185
 186    It's also good to mention that its fields represent everything
 187    that we currently know about a syscall in GDB.  */
 188 struct syscall
 189   {
 190     /* The syscall number.  */
 191     int number;
 192
 193     /* The syscall name.  */
 194     const char *name;
 195   };
 196
 197 /* Return a pretty printed form of target_waitstatus.
 198    Space for the result is malloc'd, caller must free.  */
 199 extern char *target_waitstatus_to_string (const struct target_waitstatus *);
 200
 201 /* Possible types of events that the inferior handler will have to
 202    deal with.  */
 203 enum inferior_event_type
 204   {
 205     /* Process a normal inferior event which will result in target_wait
 206        being called.  */
 207     INF_REG_EVENT,
 208     /* We are called because a timer went off.  */
 209     INF_TIMER,
 210     /* We are called to do stuff after the inferior stops.  */
 211     INF_EXEC_COMPLETE,
 212     /* We are called to do some stuff after the inferior stops, but we
 213        are expected to reenter the proceed() and
 214        handle_inferior_event() functions.  This is used only in case of
 215        'step n' like commands.  */
 216     INF_EXEC_CONTINUE
 217   };
 218 \f
 219 /* Target objects which can be transfered using target_read,
 220    target_write, et cetera.  */
 221
 222 enum target_object
 223 {
 224   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 225   TARGET_OBJECT_AVR,
 226   /* SPU target specific transfer.  See "spu-tdep.c".  */
 227   TARGET_OBJECT_SPU,
 228   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 229   TARGET_OBJECT_MEMORY,
 230   /* Memory, avoiding GDB's data cache and trusting the executable.
 231      Target implementations of to_xfer_partial never need to handle
 232      this object, and most callers should not use it.  */
 233   TARGET_OBJECT_RAW_MEMORY,
 234   /* Memory known to be part of the target's stack.  This is cached even
 235      if it is not in a region marked as such, since it is known to be
 236      "normal" RAM.  */
 237   TARGET_OBJECT_STACK_MEMORY,
 238   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 239   TARGET_OBJECT_UNWIND_TABLE,
 240   /* Transfer auxilliary vector.  */
 241   TARGET_OBJECT_AUXV,
 242   /* StackGhost cookie.  See "sparc-tdep.c".  */
 243   TARGET_OBJECT_WCOOKIE,
 244   /* Target memory map in XML format.  */
 245   TARGET_OBJECT_MEMORY_MAP,
 246   /* Flash memory.  This object can be used to write contents to
 247      a previously erased flash memory.  Using it without erasing
 248      flash can have unexpected results.  Addresses are physical
 249      address on target, and not relative to flash start.  */
 250   TARGET_OBJECT_FLASH,
 251   /* Available target-specific features, e.g. registers and coprocessors.
 252      See "target-descriptions.c".  ANNEX should never be empty.  */
 253   TARGET_OBJECT_AVAILABLE_FEATURES,
 254   /* Currently loaded libraries, in XML format.  */
 255   TARGET_OBJECT_LIBRARIES,
 256   /* Currently loaded libraries specific for SVR4 systems, in XML format.  */
 257   TARGET_OBJECT_LIBRARIES_SVR4,
 258   /* Get OS specific data.  The ANNEX specifies the type (running
 259      processes, etc.).  The data being transfered is expected to follow
 260      the DTD specified in features/osdata.dtd.  */
 261   TARGET_OBJECT_OSDATA,
 262   /* Extra signal info.  Usually the contents of `siginfo_t' on unix
 263      platforms.  */
 264   TARGET_OBJECT_SIGNAL_INFO,
 265   /* The list of threads that are being debugged.  */
 266   TARGET_OBJECT_THREADS,
 267   /* Collected static trace data.  */
 268   TARGET_OBJECT_STATIC_TRACE_DATA,
 269   /* The HP-UX registers (those that can be obtained or modified by using
 270      the TT_LWP_RUREGS/TT_LWP_WUREGS ttrace requests).  */
 271   TARGET_OBJECT_HPUX_UREGS,
 272   /* The HP-UX shared library linkage pointer.  ANNEX should be a string
 273      image of the code address whose linkage pointer we are looking for.
 274
 275      The size of the data transfered is always 8 bytes (the size of an
 276      address on ia64).  */
 277   TARGET_OBJECT_HPUX_SOLIB_GOT,
 278   /* Traceframe info, in XML format.  */
 279   TARGET_OBJECT_TRACEFRAME_INFO,
 280   /* Load maps for FDPIC systems.  */
 281   TARGET_OBJECT_FDPIC,
 282   /* Darwin dynamic linker info data.  */
 283   TARGET_OBJECT_DARWIN_DYLD_INFO
 284   /* Possible future objects: TARGET_OBJECT_FILE, ...  */
 285 };
 286
 287 /* Enumeration of the kinds of traceframe searches that a target may
 288    be able to perform.  */
 289
 290 enum trace_find_type
 291   {
 292     tfind_number,
 293     tfind_pc,
 294     tfind_tp,
 295     tfind_range,
 296     tfind_outside,
 297   };
 298
 299 typedef struct static_tracepoint_marker *static_tracepoint_marker_p;
 300 DEF_VEC_P(static_tracepoint_marker_p);
 301
 302 /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 303    OBJECT.  The OFFSET, for a seekable object, specifies the
 304    starting point.  The ANNEX can be used to provide additional
 305    data-specific information to the target.
 306
 307    Return the number of bytes actually transfered, or -1 if the
 308    transfer is not supported or otherwise fails.  Return of a positive
 309    value less than LEN indicates that no further transfer is possible.
 310    Unlike the raw to_xfer_partial interface, callers of these
 311    functions do not need to retry partial transfers.  */
 312
 313 extern LONGEST target_read (struct target_ops *ops,
 314                             enum target_object object,
 315                             const char *annex, gdb_byte *buf,
 316                             ULONGEST offset, LONGEST len);
 317
 318 struct memory_read_result
 319   {
 320     /* First address that was read.  */
 321     ULONGEST begin;
 322     /* Past-the-end address.  */
 323     ULONGEST end;
 324     /* The data.  */
 325     gdb_byte *data;
 326 };
 327 typedef struct memory_read_result memory_read_result_s;
 328 DEF_VEC_O(memory_read_result_s);
 329
 330 extern void free_memory_read_result_vector (void *);
 331
 332 extern VEC(memory_read_result_s)* read_memory_robust (struct target_ops *ops,
 333                                                       ULONGEST offset,
 334                                                       LONGEST len);
 335
 336 extern LONGEST target_write (struct target_ops *ops,
 337                              enum target_object object,
 338                              const char *annex, const gdb_byte *buf,
 339                              ULONGEST offset, LONGEST len);
 340
 341 /* Similar to target_write, except that it also calls PROGRESS with
 342    the number of bytes written and the opaque BATON after every
 343    successful partial write (and before the first write).  This is
 344    useful for progress reporting and user interaction while writing
 345    data.  To abort the transfer, the progress callback can throw an
 346    exception.  */
 347
 348 LONGEST target_write_with_progress (struct target_ops *ops,
 349                                     enum target_object object,
 350                                     const char *annex, const gdb_byte *buf,
 351                                     ULONGEST offset, LONGEST len,
 352                                     void (*progress) (ULONGEST, void *),
 353                                     void *baton);
 354
 355 /* Wrapper to perform a full read of unknown size.  OBJECT/ANNEX will
 356    be read using OPS.  The return value will be -1 if the transfer
 357    fails or is not supported; 0 if the object is empty; or the length
 358    of the object otherwise.  If a positive value is returned, a
 359    sufficiently large buffer will be allocated using xmalloc and
 360    returned in *BUF_P containing the contents of the object.
 361
 362    This method should be used for objects sufficiently small to store
 363    in a single xmalloc'd buffer, when no fixed bound on the object's
 364    size is known in advance.  Don't try to read TARGET_OBJECT_MEMORY
 365    through this function.  */
 366
 367 extern LONGEST target_read_alloc (struct target_ops *ops,
 368                                   enum target_object object,
 369                                   const char *annex, gdb_byte **buf_p);
 370
 371 /* Read OBJECT/ANNEX using OPS.  The result is NUL-terminated and
 372    returned as a string, allocated using xmalloc.  If an error occurs
 373    or the transfer is unsupported, NULL is returned.  Empty objects
 374    are returned as allocated but empty strings.  A warning is issued
 375    if the result contains any embedded NUL bytes.  */
 376
 377 extern char *target_read_stralloc (struct target_ops *ops,
 378                                    enum target_object object,
 379                                    const char *annex);
 380
 381 /* Wrappers to target read/write that perform memory transfers.  They
 382    throw an error if the memory transfer fails.
 383
 384    NOTE: cagney/2003-10-23: The naming schema is lifted from
 385    "frame.h".  The parameter order is lifted from get_frame_memory,
 386    which in turn lifted it from read_memory.  */
 387
 388 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 389                                gdb_byte *buf, LONGEST len);
 390 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 391                                             CORE_ADDR addr, int len,
 392                                             enum bfd_endian byte_order);
 393 \f
 394 struct thread_info;             /* fwd decl for parameter list below: */
 395
 396 struct target_ops
 397   {
 398     struct target_ops *beneath; /* To the target under this one.  */
 399     char *to_shortname;         /* Name this target type */
 400     char *to_longname;          /* Name for printing */
 401     char *to_doc;               /* Documentation.  Does not include trailing
 402                                    newline, and starts with a one-line descrip-
 403                                    tion (probably similar to to_longname).  */
 404     /* Per-target scratch pad.  */
 405     void *to_data;
 406     /* The open routine takes the rest of the parameters from the
 407        command, and (if successful) pushes a new target onto the
 408        stack.  Targets should supply this routine, if only to provide
 409        an error message.  */
 410     void (*to_open) (char *, int);
 411     /* Old targets with a static target vector provide "to_close".
 412        New re-entrant targets provide "to_xclose" and that is expected
 413        to xfree everything (including the "struct target_ops").  */
 414     void (*to_xclose) (struct target_ops *targ, int quitting);
 415     void (*to_close) (int);
 416     void (*to_attach) (struct target_ops *ops, char *, int);
 417     void (*to_post_attach) (int);
 418     void (*to_detach) (struct target_ops *ops, char *, int);
 419     void (*to_disconnect) (struct target_ops *, char *, int);
 420     void (*to_resume) (struct target_ops *, ptid_t, int, enum target_signal);
 421     ptid_t (*to_wait) (struct target_ops *,
 422                        ptid_t, struct target_waitstatus *, int);
 423     void (*to_fetch_registers) (struct target_ops *, struct regcache *, int);
 424     void (*to_store_registers) (struct target_ops *, struct regcache *, int);
 425     void (*to_prepare_to_store) (struct regcache *);
 426
 427     /* Transfer LEN bytes of memory between GDB address MYADDR and
 428        target address MEMADDR.  If WRITE, transfer them to the target, else
 429        transfer them from the target.  TARGET is the target from which we
 430        get this function.
 431
 432        Return value, N, is one of the following:
 433
 434        0 means that we can't handle this.  If errno has been set, it is the
 435        error which prevented us from doing it (FIXME: What about bfd_error?).
 436
 437        positive (call it N) means that we have transferred N bytes
 438        starting at MEMADDR.  We might be able to handle more bytes
 439        beyond this length, but no promises.
 440
 441        negative (call its absolute value N) means that we cannot
 442        transfer right at MEMADDR, but we could transfer at least
 443        something at MEMADDR + N.
 444
 445        NOTE: cagney/2004-10-01: This has been entirely superseeded by
 446        to_xfer_partial and inferior inheritance.  */
 447
 448     int (*deprecated_xfer_memory) (CORE_ADDR memaddr, gdb_byte *myaddr,
 449                                    int len, int write,
 450                                    struct mem_attrib *attrib,
 451                                    struct target_ops *target);
 452
 453     void (*to_files_info) (struct target_ops *);
 454     int (*to_insert_breakpoint) (struct gdbarch *, struct bp_target_info *);
 455     int (*to_remove_breakpoint) (struct gdbarch *, struct bp_target_info *);
 456     int (*to_can_use_hw_breakpoint) (int, int, int);
 457     int (*to_ranged_break_num_registers) (struct target_ops *);
 458     int (*to_insert_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 459     int (*to_remove_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 460
 461     /* Documentation of what the two routines below are expected to do is
 462        provided with the corresponding target_* macros.  */
 463     int (*to_remove_watchpoint) (CORE_ADDR, int, int, struct expression *);
 464     int (*to_insert_watchpoint) (CORE_ADDR, int, int, struct expression *);
 465
 466     int (*to_insert_mask_watchpoint) (struct target_ops *,
 467                                       CORE_ADDR, CORE_ADDR, int);
 468     int (*to_remove_mask_watchpoint) (struct target_ops *,
 469                                       CORE_ADDR, CORE_ADDR, int);
 470     int (*to_stopped_by_watchpoint) (void);
 471     int to_have_steppable_watchpoint;
 472     int to_have_continuable_watchpoint;
 473     int (*to_stopped_data_address) (struct target_ops *, CORE_ADDR *);
 474     int (*to_watchpoint_addr_within_range) (struct target_ops *,
 475                                             CORE_ADDR, CORE_ADDR, int);
 476
 477     /* Documentation of this routine is provided with the corresponding
 478        target_* macro.  */
 479     int (*to_region_ok_for_hw_watchpoint) (CORE_ADDR, int);
 480
 481     int (*to_can_accel_watchpoint_condition) (CORE_ADDR, int, int,
 482                                               struct expression *);
 483     int (*to_masked_watch_num_registers) (struct target_ops *,
 484                                           CORE_ADDR, CORE_ADDR);
 485     void (*to_terminal_init) (void);
 486     void (*to_terminal_inferior) (void);
 487     void (*to_terminal_ours_for_output) (void);
 488     void (*to_terminal_ours) (void);
 489     void (*to_terminal_save_ours) (void);
 490     void (*to_terminal_info) (char *, int);
 491     void (*to_kill) (struct target_ops *);
 492     void (*to_load) (char *, int);
 493     void (*to_create_inferior) (struct target_ops *,
 494                                 char *, char *, char **, int);
 495     void (*to_post_startup_inferior) (ptid_t);
 496     int (*to_insert_fork_catchpoint) (int);
 497     int (*to_remove_fork_catchpoint) (int);
 498     int (*to_insert_vfork_catchpoint) (int);
 499     int (*to_remove_vfork_catchpoint) (int);
 500     int (*to_follow_fork) (struct target_ops *, int);
 501     int (*to_insert_exec_catchpoint) (int);
 502     int (*to_remove_exec_catchpoint) (int);
 503     int (*to_set_syscall_catchpoint) (int, int, int, int, int *);
 504     int (*to_has_exited) (int, int, int *);
 505     void (*to_mourn_inferior) (struct target_ops *);
 506     int (*to_can_run) (void);
 507
 508     /* Documentation of this routine is provided with the corresponding
 509        target_* macro.  */
 510     void (*to_pass_signals) (int, unsigned char *);
 511
 512     int (*to_thread_alive) (struct target_ops *, ptid_t ptid);
 513     void (*to_find_new_threads) (struct target_ops *);
 514     char *(*to_pid_to_str) (struct target_ops *, ptid_t);
 515     char *(*to_extra_thread_info) (struct thread_info *);
 516     char *(*to_thread_name) (struct thread_info *);
 517     void (*to_stop) (ptid_t);
 518     void (*to_rcmd) (char *command, struct ui_file *output);
 519     char *(*to_pid_to_exec_file) (int pid);
 520     void (*to_log_command) (const char *);
 521     struct target_section_table *(*to_get_section_table) (struct target_ops *);
 522     enum strata to_stratum;
 523     int (*to_has_all_memory) (struct target_ops *);
 524     int (*to_has_memory) (struct target_ops *);
 525     int (*to_has_stack) (struct target_ops *);
 526     int (*to_has_registers) (struct target_ops *);
 527     int (*to_has_execution) (struct target_ops *, ptid_t);
 528     int to_has_thread_control;  /* control thread execution */
 529     int to_attach_no_wait;
 530     /* ASYNC target controls */
 531     int (*to_can_async_p) (void);
 532     int (*to_is_async_p) (void);
 533     void (*to_async) (void (*) (enum inferior_event_type, void *), void *);
 534     int (*to_supports_non_stop) (void);
 535     /* find_memory_regions support method for gcore */
 536     int (*to_find_memory_regions) (find_memory_region_ftype func, void *data);
 537     /* make_corefile_notes support method for gcore */
 538     char * (*to_make_corefile_notes) (bfd *, int *);
 539     /* get_bookmark support method for bookmarks */
 540     gdb_byte * (*to_get_bookmark) (char *, int);
 541     /* goto_bookmark support method for bookmarks */
 542     void (*to_goto_bookmark) (gdb_byte *, int);
 543     /* Return the thread-local address at OFFSET in the
 544        thread-local storage for the thread PTID and the shared library
 545        or executable file given by OBJFILE.  If that block of
 546        thread-local storage hasn't been allocated yet, this function
 547        may return an error.  */
 548     CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
 549                                               ptid_t ptid,
 550                                               CORE_ADDR load_module_addr,
 551                                               CORE_ADDR offset);
 552
 553     /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 554        OBJECT.  The OFFSET, for a seekable object, specifies the
 555        starting point.  The ANNEX can be used to provide additional
 556        data-specific information to the target.
 557
 558        Return the number of bytes actually transfered, zero when no
 559        further transfer is possible, and -1 when the transfer is not
 560        supported.  Return of a positive value smaller than LEN does
 561        not indicate the end of the object, only the end of the
 562        transfer; higher level code should continue transferring if
 563        desired.  This is handled in target.c.
 564
 565        The interface does not support a "retry" mechanism.  Instead it
 566        assumes that at least one byte will be transfered on each
 567        successful call.
 568
 569        NOTE: cagney/2003-10-17: The current interface can lead to
 570        fragmented transfers.  Lower target levels should not implement
 571        hacks, such as enlarging the transfer, in an attempt to
 572        compensate for this.  Instead, the target stack should be
 573        extended so that it implements supply/collect methods and a
 574        look-aside object cache.  With that available, the lowest
 575        target can safely and freely "push" data up the stack.
 576
 577        See target_read and target_write for more information.  One,
 578        and only one, of readbuf or writebuf must be non-NULL.  */
 579
 580     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 581                                 enum target_object object, const char *annex,
 582                                 gdb_byte *readbuf, const gdb_byte *writebuf,
 583                                 ULONGEST offset, LONGEST len);
 584
 585     /* Returns the memory map for the target.  A return value of NULL
 586        means that no memory map is available.  If a memory address
 587        does not fall within any returned regions, it's assumed to be
 588        RAM.  The returned memory regions should not overlap.
 589
 590        The order of regions does not matter; target_memory_map will
 591        sort regions by starting address.  For that reason, this
 592        function should not be called directly except via
 593        target_memory_map.
 594
 595        This method should not cache data; if the memory map could
 596        change unexpectedly, it should be invalidated, and higher
 597        layers will re-fetch it.  */
 598     VEC(mem_region_s) *(*to_memory_map) (struct target_ops *);
 599
 600     /* Erases the region of flash memory starting at ADDRESS, of
 601        length LENGTH.
 602
 603        Precondition: both ADDRESS and ADDRESS+LENGTH should be aligned
 604        on flash block boundaries, as reported by 'to_memory_map'.  */
 605     void (*to_flash_erase) (struct target_ops *,
 606                            ULONGEST address, LONGEST length);
 607
 608     /* Finishes a flash memory write sequence.  After this operation
 609        all flash memory should be available for writing and the result
 610        of reading from areas written by 'to_flash_write' should be
 611        equal to what was written.  */
 612     void (*to_flash_done) (struct target_ops *);
 613
 614     /* Describe the architecture-specific features of this target.
 615        Returns the description found, or NULL if no description
 616        was available.  */
 617     const struct target_desc *(*to_read_description) (struct target_ops *ops);
 618
 619     /* Build the PTID of the thread on which a given task is running,
 620        based on LWP and THREAD.  These values are extracted from the
 621        task Private_Data section of the Ada Task Control Block, and
 622        their interpretation depends on the target.  */
 623     ptid_t (*to_get_ada_task_ptid) (long lwp, long thread);
 624
 625     /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
 626        Return 0 if *READPTR is already at the end of the buffer.
 627        Return -1 if there is insufficient buffer for a whole entry.
 628        Return 1 if an entry was read into *TYPEP and *VALP.  */
 629     int (*to_auxv_parse) (struct target_ops *ops, gdb_byte **readptr,
 630                          gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 631
 632     /* Search SEARCH_SPACE_LEN bytes beginning at START_ADDR for the
 633        sequence of bytes in PATTERN with length PATTERN_LEN.
 634
 635        The result is 1 if found, 0 if not found, and -1 if there was an error
 636        requiring halting of the search (e.g. memory read error).
 637        If the pattern is found the address is recorded in FOUND_ADDRP.  */
 638     int (*to_search_memory) (struct target_ops *ops,
 639                              CORE_ADDR start_addr, ULONGEST search_space_len,
 640                              const gdb_byte *pattern, ULONGEST pattern_len,
 641                              CORE_ADDR *found_addrp);
 642
 643     /* Can target execute in reverse?  */
 644     int (*to_can_execute_reverse) (void);
 645
 646     /* The direction the target is currently executing.  Must be
 647        implemented on targets that support reverse execution and async
 648        mode.  The default simply returns forward execution.  */
 649     enum exec_direction_kind (*to_execution_direction) (void);
 650
 651     /* Does this target support debugging multiple processes
 652        simultaneously?  */
 653     int (*to_supports_multi_process) (void);
 654
 655     /* Does this target support enabling and disabling tracepoints while a trace
 656        experiment is running?  */
 657     int (*to_supports_enable_disable_tracepoint) (void);
 658
 659     /* Does this target support disabling address space randomization?  */
 660     int (*to_supports_disable_randomization) (void);
 661
 662     /* Does this target support the tracenz bytecode for string collection?  */
 663     int (*to_supports_string_tracing) (void);
 664
 665     /* Does this target support evaluation of breakpoint conditions on its
 666        end?  */
 667     int (*to_supports_evaluation_of_breakpoint_conditions) (void);
 668
 669     /* Determine current architecture of thread PTID.
 670
 671        The target is supposed to determine the architecture of the code where
 672        the target is currently stopped at (on Cell, if a target is in spu_run,
 673        to_thread_architecture would return SPU, otherwise PPC32 or PPC64).
 674        This is architecture used to perform decr_pc_after_break adjustment,
 675        and also determines the frame architecture of the innermost frame.
 676        ptrace operations need to operate according to target_gdbarch.
 677
 678        The default implementation always returns target_gdbarch.  */
 679     struct gdbarch *(*to_thread_architecture) (struct target_ops *, ptid_t);
 680
 681     /* Determine current address space of thread PTID.
 682
 683        The default implementation always returns the inferior's
 684        address space.  */
 685     struct address_space *(*to_thread_address_space) (struct target_ops *,
 686                                                       ptid_t);
 687
 688     /* Target file operations.  */
 689
 690     /* Open FILENAME on the target, using FLAGS and MODE.  Return a
 691        target file descriptor, or -1 if an error occurs (and set
 692        *TARGET_ERRNO).  */
 693     int (*to_fileio_open) (const char *filename, int flags, int mode,
 694                            int *target_errno);
 695
 696     /* Write up to LEN bytes from WRITE_BUF to FD on the target.
 697        Return the number of bytes written, or -1 if an error occurs
 698        (and set *TARGET_ERRNO).  */
 699     int (*to_fileio_pwrite) (int fd, const gdb_byte *write_buf, int len,
 700                              ULONGEST offset, int *target_errno);
 701
 702     /* Read up to LEN bytes FD on the target into READ_BUF.
 703        Return the number of bytes read, or -1 if an error occurs
 704        (and set *TARGET_ERRNO).  */
 705     int (*to_fileio_pread) (int fd, gdb_byte *read_buf, int len,
 706                             ULONGEST offset, int *target_errno);
 707
 708     /* Close FD on the target.  Return 0, or -1 if an error occurs
 709        (and set *TARGET_ERRNO).  */
 710     int (*to_fileio_close) (int fd, int *target_errno);
 711
 712     /* Unlink FILENAME on the target.  Return 0, or -1 if an error
 713        occurs (and set *TARGET_ERRNO).  */
 714     int (*to_fileio_unlink) (const char *filename, int *target_errno);
 715
 716     /* Read value of symbolic link FILENAME on the target.  Return a
 717        null-terminated string allocated via xmalloc, or NULL if an error
 718        occurs (and set *TARGET_ERRNO).  */
 719     char *(*to_fileio_readlink) (const char *filename, int *target_errno);
 720
 721
 722     /* Implement the "info proc" command.  */
 723     void (*to_info_proc) (struct target_ops *, char *, enum info_proc_what);
 724
 725     /* Tracepoint-related operations.  */
 726
 727     /* Prepare the target for a tracing run.  */
 728     void (*to_trace_init) (void);
 729
 730     /* Send full details of a tracepoint location to the target.  */
 731     void (*to_download_tracepoint) (struct bp_location *location);
 732
 733     /* Is the target able to download tracepoint locations in current
 734        state?  */
 735     int (*to_can_download_tracepoint) (void);
 736
 737     /* Send full details of a trace state variable to the target.  */
 738     void (*to_download_trace_state_variable) (struct trace_state_variable *tsv);
 739
 740     /* Enable a tracepoint on the target.  */
 741     void (*to_enable_tracepoint) (struct bp_location *location);
 742
 743     /* Disable a tracepoint on the target.  */
 744     void (*to_disable_tracepoint) (struct bp_location *location);
 745
 746     /* Inform the target info of memory regions that are readonly
 747        (such as text sections), and so it should return data from
 748        those rather than look in the trace buffer.  */
 749     void (*to_trace_set_readonly_regions) (void);
 750
 751     /* Start a trace run.  */
 752     void (*to_trace_start) (void);
 753
 754     /* Get the current status of a tracing run.  */
 755     int (*to_get_trace_status) (struct trace_status *ts);
 756
 757     void (*to_get_tracepoint_status) (struct breakpoint *tp,
 758                                       struct uploaded_tp *utp);
 759
 760     /* Stop a trace run.  */
 761     void (*to_trace_stop) (void);
 762
 763    /* Ask the target to find a trace frame of the given type TYPE,
 764       using NUM, ADDR1, and ADDR2 as search parameters.  Returns the
 765       number of the trace frame, and also the tracepoint number at
 766       TPP.  If no trace frame matches, return -1.  May throw if the
 767       operation fails.  */
 768     int (*to_trace_find) (enum trace_find_type type, int num,
 769                           ULONGEST addr1, ULONGEST addr2, int *tpp);
 770
 771     /* Get the value of the trace state variable number TSV, returning
 772        1 if the value is known and writing the value itself into the
 773        location pointed to by VAL, else returning 0.  */
 774     int (*to_get_trace_state_variable_value) (int tsv, LONGEST *val);
 775
 776     int (*to_save_trace_data) (const char *filename);
 777
 778     int (*to_upload_tracepoints) (struct uploaded_tp **utpp);
 779
 780     int (*to_upload_trace_state_variables) (struct uploaded_tsv **utsvp);
 781
 782     LONGEST (*to_get_raw_trace_data) (gdb_byte *buf,
 783                                       ULONGEST offset, LONGEST len);
 784
 785     /* Get the minimum length of instruction on which a fast tracepoint
 786        may be set on the target.  If this operation is unsupported,
 787        return -1.  If for some reason the minimum length cannot be
 788        determined, return 0.  */
 789     int (*to_get_min_fast_tracepoint_insn_len) (void);
 790
 791     /* Set the target's tracing behavior in response to unexpected
 792        disconnection - set VAL to 1 to keep tracing, 0 to stop.  */
 793     void (*to_set_disconnected_tracing) (int val);
 794     void (*to_set_circular_trace_buffer) (int val);
 795
 796     /* Add/change textual notes about the trace run, returning 1 if
 797        successful, 0 otherwise.  */
 798     int (*to_set_trace_notes) (char *user, char *notes, char* stopnotes);
 799
 800     /* Return the processor core that thread PTID was last seen on.
 801        This information is updated only when:
 802        - update_thread_list is called
 803        - thread stops
 804        If the core cannot be determined -- either for the specified
 805        thread, or right now, or in this debug session, or for this
 806        target -- return -1.  */
 807     int (*to_core_of_thread) (struct target_ops *, ptid_t ptid);
 808
 809     /* Verify that the memory in the [MEMADDR, MEMADDR+SIZE) range
 810        matches the contents of [DATA,DATA+SIZE).  Returns 1 if there's
 811        a match, 0 if there's a mismatch, and -1 if an error is
 812        encountered while reading memory.  */
 813     int (*to_verify_memory) (struct target_ops *, const gdb_byte *data,
 814                              CORE_ADDR memaddr, ULONGEST size);
 815
 816     /* Return the address of the start of the Thread Information Block
 817        a Windows OS specific feature.  */
 818     int (*to_get_tib_address) (ptid_t ptid, CORE_ADDR *addr);
 819
 820     /* Send the new settings of write permission variables.  */
 821     void (*to_set_permissions) (void);
 822
 823     /* Look for a static tracepoint marker at ADDR, and fill in MARKER
 824        with its details.  Return 1 on success, 0 on failure.  */
 825     int (*to_static_tracepoint_marker_at) (CORE_ADDR,
 826                                            struct static_tracepoint_marker *marker);
 827
 828     /* Return a vector of all tracepoints markers string id ID, or all
 829        markers if ID is NULL.  */
 830     VEC(static_tracepoint_marker_p) *(*to_static_tracepoint_markers_by_strid)
 831       (const char *id);
 832
 833     /* Return a traceframe info object describing the current
 834        traceframe's contents.  This method should not cache data;
 835        higher layers take care of caching, invalidating, and
 836        re-fetching when necessary.  */
 837     struct traceframe_info *(*to_traceframe_info) (void);
 838
 839     int to_magic;
 840     /* Need sub-structure for target machine related rather than comm related?
 841      */
 842   };
 843
 844 /* Magic number for checking ops size.  If a struct doesn't end with this
 845    number, somebody changed the declaration but didn't change all the
 846    places that initialize one.  */
 847
 848 #define OPS_MAGIC       3840
 849
 850 /* The ops structure for our "current" target process.  This should
 851    never be NULL.  If there is no target, it points to the dummy_target.  */
 852
 853 extern struct target_ops current_target;
 854
 855 /* Define easy words for doing these operations on our current target.  */
 856
 857 #define target_shortname        (current_target.to_shortname)
 858 #define target_longname         (current_target.to_longname)
 859
 860 /* Does whatever cleanup is required for a target that we are no
 861    longer going to be calling.  QUITTING indicates that GDB is exiting
 862    and should not get hung on an error (otherwise it is important to
 863    perform clean termination, even if it takes a while).  This routine
 864    is automatically always called after popping the target off the
 865    target stack - the target's own methods are no longer available
 866    through the target vector.  Closing file descriptors and freeing all
 867    memory allocated memory are typical things it should do.  */
 868
 869 void target_close (struct target_ops *targ, int quitting);
 870
 871 /* Attaches to a process on the target side.  Arguments are as passed
 872    to the `attach' command by the user.  This routine can be called
 873    when the target is not on the target-stack, if the target_can_run
 874    routine returns 1; in that case, it must push itself onto the stack.
 875    Upon exit, the target should be ready for normal operations, and
 876    should be ready to deliver the status of the process immediately
 877    (without waiting) to an upcoming target_wait call.  */
 878
 879 void target_attach (char *, int);
 880
 881 /* Some targets don't generate traps when attaching to the inferior,
 882    or their target_attach implementation takes care of the waiting.
 883    These targets must set to_attach_no_wait.  */
 884
 885 #define target_attach_no_wait \
 886      (current_target.to_attach_no_wait)
 887
 888 /* The target_attach operation places a process under debugger control,
 889    and stops the process.
 890
 891    This operation provides a target-specific hook that allows the
 892    necessary bookkeeping to be performed after an attach completes.  */
 893 #define target_post_attach(pid) \
 894      (*current_target.to_post_attach) (pid)
 895
 896 /* Takes a program previously attached to and detaches it.
 897    The program may resume execution (some targets do, some don't) and will
 898    no longer stop on signals, etc.  We better not have left any breakpoints
 899    in the program or it'll die when it hits one.  ARGS is arguments
 900    typed by the user (e.g. a signal to send the process).  FROM_TTY
 901    says whether to be verbose or not.  */
 902
 903 extern void target_detach (char *, int);
 904
 905 /* Disconnect from the current target without resuming it (leaving it
 906    waiting for a debugger).  */
 907
 908 extern void target_disconnect (char *, int);
 909
 910 /* Resume execution of the target process PTID.  STEP says whether to
 911    single-step or to run free; SIGGNAL is the signal to be given to
 912    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 913    pass TARGET_SIGNAL_DEFAULT.  */
 914
 915 extern void target_resume (ptid_t ptid, int step, enum target_signal signal);
 916
 917 /* Wait for process pid to do something.  PTID = -1 to wait for any
 918    pid to do something.  Return pid of child, or -1 in case of error;
 919    store status through argument pointer STATUS.  Note that it is
 920    _NOT_ OK to throw_exception() out of target_wait() without popping
 921    the debugging target from the stack; GDB isn't prepared to get back
 922    to the prompt with a debugging target but without the frame cache,
 923    stop_pc, etc., set up.  OPTIONS is a bitwise OR of TARGET_W*
 924    options.  */
 925
 926 extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status,
 927                            int options);
 928
 929 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 930
 931 extern void target_fetch_registers (struct regcache *regcache, int regno);
 932
 933 /* Store at least register REGNO, or all regs if REGNO == -1.
 934    It can store as many registers as it wants to, so target_prepare_to_store
 935    must have been previously called.  Calls error() if there are problems.  */
 936
 937 extern void target_store_registers (struct regcache *regcache, int regs);
 938
 939 /* Get ready to modify the registers array.  On machines which store
 940    individual registers, this doesn't need to do anything.  On machines
 941    which store all the registers in one fell swoop, this makes sure
 942    that REGISTERS contains all the registers from the program being
 943    debugged.  */
 944
 945 #define target_prepare_to_store(regcache)       \
 946      (*current_target.to_prepare_to_store) (regcache)
 947
 948 /* Determine current address space of thread PTID.  */
 949
 950 struct address_space *target_thread_address_space (ptid_t);
 951
 952 /* Implement the "info proc" command.  */
 953
 954 void target_info_proc (char *, enum info_proc_what);
 955
 956 /* Returns true if this target can debug multiple processes
 957    simultaneously.  */
 958
 959 #define target_supports_multi_process() \
 960      (*current_target.to_supports_multi_process) ()
 961
 962 /* Returns true if this target can disable address space randomization.  */
 963
 964 int target_supports_disable_randomization (void);
 965
 966 /* Returns true if this target can enable and disable tracepoints
 967    while a trace experiment is running.  */
 968
 969 #define target_supports_enable_disable_tracepoint() \
 970   (*current_target.to_supports_enable_disable_tracepoint) ()
 971
 972 #define target_supports_string_tracing() \
 973   (*current_target.to_supports_string_tracing) ()
 974
 975 /* Returns true if this target can handle breakpoint conditions
 976    on its end.  */
 977
 978 #define target_supports_evaluation_of_breakpoint_conditions() \
 979   (*current_target.to_supports_evaluation_of_breakpoint_conditions) ()
 980
 981 /* Invalidate all target dcaches.  */
 982 extern void target_dcache_invalidate (void);
 983
 984 extern int target_read_string (CORE_ADDR, char **, int, int *);
 985
 986 extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 987
 988 extern int target_read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 989
 990 extern int target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 991                                 int len);
 992
 993 extern int target_write_raw_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 994                                     int len);
 995
 996 /* Fetches the target's memory map.  If one is found it is sorted
 997    and returned, after some consistency checking.  Otherwise, NULL
 998    is returned.  */
 999 VEC(mem_region_s) *target_memory_map (void);
1000
1001 /* Erase the specified flash region.  */
1002 void target_flash_erase (ULONGEST address, LONGEST length);
1003
1004 /* Finish a sequence of flash operations.  */
1005 void target_flash_done (void);
1006
1007 /* Describes a request for a memory write operation.  */
1008 struct memory_write_request
1009   {
1010     /* Begining address that must be written.  */
1011     ULONGEST begin;
1012     /* Past-the-end address.  */
1013     ULONGEST end;
1014     /* The data to write.  */
1015     gdb_byte *data;
1016     /* A callback baton for progress reporting for this request.  */
1017     void *baton;
1018   };
1019 typedef struct memory_write_request memory_write_request_s;
1020 DEF_VEC_O(memory_write_request_s);
1021
1022 /* Enumeration specifying different flash preservation behaviour.  */
1023 enum flash_preserve_mode
1024   {
1025     flash_preserve,
1026     flash_discard
1027   };
1028
1029 /* Write several memory blocks at once.  This version can be more
1030    efficient than making several calls to target_write_memory, in
1031    particular because it can optimize accesses to flash memory.
1032
1033    Moreover, this is currently the only memory access function in gdb
1034    that supports writing to flash memory, and it should be used for
1035    all cases where access to flash memory is desirable.
1036
1037    REQUESTS is the vector (see vec.h) of memory_write_request.
1038    PRESERVE_FLASH_P indicates what to do with blocks which must be
1039      erased, but not completely rewritten.
1040    PROGRESS_CB is a function that will be periodically called to provide
1041      feedback to user.  It will be called with the baton corresponding
1042      to the request currently being written.  It may also be called
1043      with a NULL baton, when preserved flash sectors are being rewritten.
1044
1045    The function returns 0 on success, and error otherwise.  */
1046 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
1047                                 enum flash_preserve_mode preserve_flash_p,
1048                                 void (*progress_cb) (ULONGEST, void *));
1049
1050 /* From infrun.c.  */
1051
1052 extern int inferior_has_forked (ptid_t pid, ptid_t *child_pid);
1053
1054 extern int inferior_has_vforked (ptid_t pid, ptid_t *child_pid);
1055
1056 extern int inferior_has_execd (ptid_t pid, char **execd_pathname);
1057
1058 extern int inferior_has_called_syscall (ptid_t pid, int *syscall_number);
1059
1060 /* Print a line about the current target.  */
1061
1062 #define target_files_info()     \
1063      (*current_target.to_files_info) (&current_target)
1064
1065 /* Insert a breakpoint at address BP_TGT->placed_address in the target
1066    machine.  Result is 0 for success, or an errno value.  */
1067
1068 extern int target_insert_breakpoint (struct gdbarch *gdbarch,
1069                                      struct bp_target_info *bp_tgt);
1070
1071 /* Remove a breakpoint at address BP_TGT->placed_address in the target
1072    machine.  Result is 0 for success, or an errno value.  */
1073
1074 extern int target_remove_breakpoint (struct gdbarch *gdbarch,
1075                                      struct bp_target_info *bp_tgt);
1076
1077 /* Initialize the terminal settings we record for the inferior,
1078    before we actually run the inferior.  */
1079
1080 #define target_terminal_init() \
1081      (*current_target.to_terminal_init) ()
1082
1083 /* Put the inferior's terminal settings into effect.
1084    This is preparation for starting or resuming the inferior.  */
1085
1086 extern void target_terminal_inferior (void);
1087
1088 /* Put some of our terminal settings into effect,
1089    enough to get proper results from our output,
1090    but do not change into or out of RAW mode
1091    so that no input is discarded.
1092
1093    After doing this, either terminal_ours or terminal_inferior
1094    should be called to get back to a normal state of affairs.  */
1095
1096 #define target_terminal_ours_for_output() \
1097      (*current_target.to_terminal_ours_for_output) ()
1098
1099 /* Put our terminal settings into effect.
1100    First record the inferior's terminal settings
1101    so they can be restored properly later.  */
1102
1103 #define target_terminal_ours() \
1104      (*current_target.to_terminal_ours) ()
1105
1106 /* Save our terminal settings.
1107    This is called from TUI after entering or leaving the curses
1108    mode.  Since curses modifies our terminal this call is here
1109    to take this change into account.  */
1110
1111 #define target_terminal_save_ours() \
1112      (*current_target.to_terminal_save_ours) ()
1113
1114 /* Print useful information about our terminal status, if such a thing
1115    exists.  */
1116
1117 #define target_terminal_info(arg, from_tty) \
1118      (*current_target.to_terminal_info) (arg, from_tty)
1119
1120 /* Kill the inferior process.   Make it go away.  */
1121
1122 extern void target_kill (void);
1123
1124 /* Load an executable file into the target process.  This is expected
1125    to not only bring new code into the target process, but also to
1126    update GDB's symbol tables to match.
1127
1128    ARG contains command-line arguments, to be broken down with
1129    buildargv ().  The first non-switch argument is the filename to
1130    load, FILE; the second is a number (as parsed by strtoul (..., ...,
1131    0)), which is an offset to apply to the load addresses of FILE's
1132    sections.  The target may define switches, or other non-switch
1133    arguments, as it pleases.  */
1134
1135 extern void target_load (char *arg, int from_tty);
1136
1137 /* Start an inferior process and set inferior_ptid to its pid.
1138    EXEC_FILE is the file to run.
1139    ALLARGS is a string containing the arguments to the program.
1140    ENV is the environment vector to pass.  Errors reported with error().
1141    On VxWorks and various standalone systems, we ignore exec_file.  */
1142
1143 void target_create_inferior (char *exec_file, char *args,
1144                              char **env, int from_tty);
1145
1146 /* Some targets (such as ttrace-based HPUX) don't allow us to request
1147    notification of inferior events such as fork and vork immediately
1148    after the inferior is created.  (This because of how gdb gets an
1149    inferior created via invoking a shell to do it.  In such a scenario,
1150    if the shell init file has commands in it, the shell will fork and
1151    exec for each of those commands, and we will see each such fork
1152    event.  Very bad.)
1153
1154    Such targets will supply an appropriate definition for this function.  */
1155
1156 #define target_post_startup_inferior(ptid) \
1157      (*current_target.to_post_startup_inferior) (ptid)
1158
1159 /* On some targets, we can catch an inferior fork or vfork event when
1160    it occurs.  These functions insert/remove an already-created
1161    catchpoint for such events.  They return  0 for success, 1 if the
1162    catchpoint type is not supported and -1 for failure.  */
1163
1164 #define target_insert_fork_catchpoint(pid) \
1165      (*current_target.to_insert_fork_catchpoint) (pid)
1166
1167 #define target_remove_fork_catchpoint(pid) \
1168      (*current_target.to_remove_fork_catchpoint) (pid)
1169
1170 #define target_insert_vfork_catchpoint(pid) \
1171      (*current_target.to_insert_vfork_catchpoint) (pid)
1172
1173 #define target_remove_vfork_catchpoint(pid) \
1174      (*current_target.to_remove_vfork_catchpoint) (pid)
1175
1176 /* If the inferior forks or vforks, this function will be called at
1177    the next resume in order to perform any bookkeeping and fiddling
1178    necessary to continue debugging either the parent or child, as
1179    requested, and releasing the other.  Information about the fork
1180    or vfork event is available via get_last_target_status ().
1181    This function returns 1 if the inferior should not be resumed
1182    (i.e. there is another event pending).  */
1183
1184 int target_follow_fork (int follow_child);
1185
1186 /* On some targets, we can catch an inferior exec event when it
1187    occurs.  These functions insert/remove an already-created
1188    catchpoint for such events.  They return  0 for success, 1 if the
1189    catchpoint type is not supported and -1 for failure.  */
1190
1191 #define target_insert_exec_catchpoint(pid) \
1192      (*current_target.to_insert_exec_catchpoint) (pid)
1193
1194 #define target_remove_exec_catchpoint(pid) \
1195      (*current_target.to_remove_exec_catchpoint) (pid)
1196
1197 /* Syscall catch.
1198
1199    NEEDED is nonzero if any syscall catch (of any kind) is requested.
1200    If NEEDED is zero, it means the target can disable the mechanism to
1201    catch system calls because there are no more catchpoints of this type.
1202
1203    ANY_COUNT is nonzero if a generic (filter-less) syscall catch is
1204    being requested.  In this case, both TABLE_SIZE and TABLE should
1205    be ignored.
1206
1207    TABLE_SIZE is the number of elements in TABLE.  It only matters if
1208    ANY_COUNT is zero.
1209
1210    TABLE is an array of ints, indexed by syscall number.  An element in
1211    this array is nonzero if that syscall should be caught.  This argument
1212    only matters if ANY_COUNT is zero.
1213
1214    Return 0 for success, 1 if syscall catchpoints are not supported or -1
1215    for failure.  */
1216
1217 #define target_set_syscall_catchpoint(pid, needed, any_count, table_size, table) \
1218      (*current_target.to_set_syscall_catchpoint) (pid, needed, any_count, \
1219                                                   table_size, table)
1220
1221 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
1222    exit code of PID, if any.  */
1223
1224 #define target_has_exited(pid,wait_status,exit_status) \
1225      (*current_target.to_has_exited) (pid,wait_status,exit_status)
1226
1227 /* The debugger has completed a blocking wait() call.  There is now
1228    some process event that must be processed.  This function should
1229    be defined by those targets that require the debugger to perform
1230    cleanup or internal state changes in response to the process event.  */
1231
1232 /* The inferior process has died.  Do what is right.  */
1233
1234 void target_mourn_inferior (void);
1235
1236 /* Does target have enough data to do a run or attach command? */
1237
1238 #define target_can_run(t) \
1239      ((t)->to_can_run) ()
1240
1241 /* Set list of signals to be handled in the target.
1242
1243    PASS_SIGNALS is an array of size NSIG, indexed by target signal number
1244    (enum target_signal).  For every signal whose entry in this array is
1245    non-zero, the target is allowed -but not required- to skip reporting
1246    arrival of the signal to the GDB core by returning from target_wait,
1247    and to pass the signal directly to the inferior instead.
1248
1249    However, if the target is hardware single-stepping a thread that is
1250    about to receive a signal, it needs to be reported in any case, even
1251    if mentioned in a previous target_pass_signals call.   */
1252
1253 extern void target_pass_signals (int nsig, unsigned char *pass_signals);
1254
1255 /* Check to see if a thread is still alive.  */
1256
1257 extern int target_thread_alive (ptid_t ptid);
1258
1259 /* Query for new threads and add them to the thread list.  */
1260
1261 extern void target_find_new_threads (void);
1262
1263 /* Make target stop in a continuable fashion.  (For instance, under
1264    Unix, this should act like SIGSTOP).  This function is normally
1265    used by GUIs to implement a stop button.  */
1266
1267 extern void target_stop (ptid_t ptid);
1268
1269 /* Send the specified COMMAND to the target's monitor
1270    (shell,interpreter) for execution.  The result of the query is
1271    placed in OUTBUF.  */
1272
1273 #define target_rcmd(command, outbuf) \
1274      (*current_target.to_rcmd) (command, outbuf)
1275
1276
1277 /* Does the target include all of memory, or only part of it?  This
1278    determines whether we look up the target chain for other parts of
1279    memory if this target can't satisfy a request.  */
1280
1281 extern int target_has_all_memory_1 (void);
1282 #define target_has_all_memory target_has_all_memory_1 ()
1283
1284 /* Does the target include memory?  (Dummy targets don't.)  */
1285
1286 extern int target_has_memory_1 (void);
1287 #define target_has_memory target_has_memory_1 ()
1288
1289 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
1290    we start a process.)  */
1291
1292 extern int target_has_stack_1 (void);
1293 #define target_has_stack target_has_stack_1 ()
1294
1295 /* Does the target have registers?  (Exec files don't.)  */
1296
1297 extern int target_has_registers_1 (void);
1298 #define target_has_registers target_has_registers_1 ()
1299
1300 /* Does the target have execution?  Can we make it jump (through
1301    hoops), or pop its stack a few times?  This means that the current
1302    target is currently executing; for some targets, that's the same as
1303    whether or not the target is capable of execution, but there are
1304    also targets which can be current while not executing.  In that
1305    case this will become true after target_create_inferior or
1306    target_attach.  */
1307
1308 extern int target_has_execution_1 (ptid_t);
1309
1310 /* Like target_has_execution_1, but always passes inferior_ptid.  */
1311
1312 extern int target_has_execution_current (void);
1313
1314 #define target_has_execution target_has_execution_current ()
1315
1316 /* Default implementations for process_stratum targets.  Return true
1317    if there's a selected inferior, false otherwise.  */
1318
1319 extern int default_child_has_all_memory (struct target_ops *ops);
1320 extern int default_child_has_memory (struct target_ops *ops);
1321 extern int default_child_has_stack (struct target_ops *ops);
1322 extern int default_child_has_registers (struct target_ops *ops);
1323 extern int default_child_has_execution (struct target_ops *ops,
1324                                         ptid_t the_ptid);
1325
1326 /* Can the target support the debugger control of thread execution?
1327    Can it lock the thread scheduler?  */
1328
1329 #define target_can_lock_scheduler \
1330      (current_target.to_has_thread_control & tc_schedlock)
1331
1332 /* Should the target enable async mode if it is supported?  Temporary
1333    cludge until async mode is a strict superset of sync mode.  */
1334 extern int target_async_permitted;
1335
1336 /* Can the target support asynchronous execution?  */
1337 #define target_can_async_p() (current_target.to_can_async_p ())
1338
1339 /* Is the target in asynchronous execution mode?  */
1340 #define target_is_async_p() (current_target.to_is_async_p ())
1341
1342 int target_supports_non_stop (void);
1343
1344 /* Put the target in async mode with the specified callback function.  */
1345 #define target_async(CALLBACK,CONTEXT) \
1346      (current_target.to_async ((CALLBACK), (CONTEXT)))
1347
1348 #define target_execution_direction() \
1349   (current_target.to_execution_direction ())
1350
1351 /* Converts a process id to a string.  Usually, the string just contains
1352    `process xyz', but on some systems it may contain
1353    `process xyz thread abc'.  */
1354
1355 extern char *target_pid_to_str (ptid_t ptid);
1356
1357 extern char *normal_pid_to_str (ptid_t ptid);
1358
1359 /* Return a short string describing extra information about PID,
1360    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1361    is okay.  */
1362
1363 #define target_extra_thread_info(TP) \
1364      (current_target.to_extra_thread_info (TP))
1365
1366 /* Return the thread's name.  A NULL result means that the target
1367    could not determine this thread's name.  */
1368
1369 extern char *target_thread_name (struct thread_info *);
1370
1371 /* Attempts to find the pathname of the executable file
1372    that was run to create a specified process.
1373
1374    The process PID must be stopped when this operation is used.
1375
1376    If the executable file cannot be determined, NULL is returned.
1377
1378    Else, a pointer to a character string containing the pathname
1379    is returned.  This string should be copied into a buffer by
1380    the client if the string will not be immediately used, or if
1381    it must persist.  */
1382
1383 #define target_pid_to_exec_file(pid) \
1384      (current_target.to_pid_to_exec_file) (pid)
1385
1386 /* See the to_thread_architecture description in struct target_ops.  */
1387
1388 #define target_thread_architecture(ptid) \
1389      (current_target.to_thread_architecture (&current_target, ptid))
1390
1391 /*
1392  * Iterator function for target memory regions.
1393  * Calls a callback function once for each memory region 'mapped'
1394  * in the child process.  Defined as a simple macro rather than
1395  * as a function macro so that it can be tested for nullity.
1396  */
1397
1398 #define target_find_memory_regions(FUNC, DATA) \
1399      (current_target.to_find_memory_regions) (FUNC, DATA)
1400
1401 /*
1402  * Compose corefile .note section.
1403  */
1404
1405 #define target_make_corefile_notes(BFD, SIZE_P) \
1406      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
1407
1408 /* Bookmark interfaces.  */
1409 #define target_get_bookmark(ARGS, FROM_TTY) \
1410      (current_target.to_get_bookmark) (ARGS, FROM_TTY)
1411
1412 #define target_goto_bookmark(ARG, FROM_TTY) \
1413      (current_target.to_goto_bookmark) (ARG, FROM_TTY)
1414
1415 /* Hardware watchpoint interfaces.  */
1416
1417 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1418    write).  Only the INFERIOR_PTID task is being queried.  */
1419
1420 #define target_stopped_by_watchpoint \
1421    (*current_target.to_stopped_by_watchpoint)
1422
1423 /* Non-zero if we have steppable watchpoints  */
1424
1425 #define target_have_steppable_watchpoint \
1426    (current_target.to_have_steppable_watchpoint)
1427
1428 /* Non-zero if we have continuable watchpoints  */
1429
1430 #define target_have_continuable_watchpoint \
1431    (current_target.to_have_continuable_watchpoint)
1432
1433 /* Provide defaults for hardware watchpoint functions.  */
1434
1435 /* If the *_hw_beakpoint functions have not been defined
1436    elsewhere use the definitions in the target vector.  */
1437
1438 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1439    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1440    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1441    (including this one?).  OTHERTYPE is who knows what...  */
1442
1443 #define target_can_use_hardware_watchpoint(TYPE,CNT,OTHERTYPE) \
1444  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1445
1446 /* Returns the number of debug registers needed to watch the given
1447    memory region, or zero if not supported.  */
1448
1449 #define target_region_ok_for_hw_watchpoint(addr, len) \
1450     (*current_target.to_region_ok_for_hw_watchpoint) (addr, len)
1451
1452
1453 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.
1454    TYPE is 0 for write, 1 for read, and 2 for read/write accesses.
1455    COND is the expression for its condition, or NULL if there's none.
1456    Returns 0 for success, 1 if the watchpoint type is not supported,
1457    -1 for failure.  */
1458
1459 #define target_insert_watchpoint(addr, len, type, cond) \
1460      (*current_target.to_insert_watchpoint) (addr, len, type, cond)
1461
1462 #define target_remove_watchpoint(addr, len, type, cond) \
1463      (*current_target.to_remove_watchpoint) (addr, len, type, cond)
1464
1465 /* Insert a new masked watchpoint at ADDR using the mask MASK.
1466    RW may be hw_read for a read watchpoint, hw_write for a write watchpoint
1467    or hw_access for an access watchpoint.  Returns 0 for success, 1 if
1468    masked watchpoints are not supported, -1 for failure.  */
1469
1470 extern int target_insert_mask_watchpoint (CORE_ADDR, CORE_ADDR, int);
1471
1472 /* Remove a masked watchpoint at ADDR with the mask MASK.
1473    RW may be hw_read for a read watchpoint, hw_write for a write watchpoint
1474    or hw_access for an access watchpoint.  Returns 0 for success, non-zero
1475    for failure.  */
1476
1477 extern int target_remove_mask_watchpoint (CORE_ADDR, CORE_ADDR, int);
1478
1479 #define target_insert_hw_breakpoint(gdbarch, bp_tgt) \
1480      (*current_target.to_insert_hw_breakpoint) (gdbarch, bp_tgt)
1481
1482 #define target_remove_hw_breakpoint(gdbarch, bp_tgt) \
1483      (*current_target.to_remove_hw_breakpoint) (gdbarch, bp_tgt)
1484
1485 /* Return number of debug registers needed for a ranged breakpoint,
1486    or -1 if ranged breakpoints are not supported.  */
1487
1488 extern int target_ranged_break_num_registers (void);
1489
1490 /* Return non-zero if target knows the data address which triggered this
1491    target_stopped_by_watchpoint, in such case place it to *ADDR_P.  Only the
1492    INFERIOR_PTID task is being queried.  */
1493 #define target_stopped_data_address(target, addr_p) \
1494     (*target.to_stopped_data_address) (target, addr_p)
1495
1496 /* Return non-zero if ADDR is within the range of a watchpoint spanning
1497    LENGTH bytes beginning at START.  */
1498 #define target_watchpoint_addr_within_range(target, addr, start, length) \
1499   (*target.to_watchpoint_addr_within_range) (target, addr, start, length)
1500
1501 /* Return non-zero if the target is capable of using hardware to evaluate
1502    the condition expression.  In this case, if the condition is false when
1503    the watched memory location changes, execution may continue without the
1504    debugger being notified.
1505
1506    Due to limitations in the hardware implementation, it may be capable of
1507    avoiding triggering the watchpoint in some cases where the condition
1508    expression is false, but may report some false positives as well.
1509    For this reason, GDB will still evaluate the condition expression when
1510    the watchpoint triggers.  */
1511 #define target_can_accel_watchpoint_condition(addr, len, type, cond) \
1512   (*current_target.to_can_accel_watchpoint_condition) (addr, len, type, cond)
1513
1514 /* Return number of debug registers needed for a masked watchpoint,
1515    -1 if masked watchpoints are not supported or -2 if the given address
1516    and mask combination cannot be used.  */
1517
1518 extern int target_masked_watch_num_registers (CORE_ADDR addr, CORE_ADDR mask);
1519
1520 /* Target can execute in reverse?  */
1521 #define target_can_execute_reverse \
1522      (current_target.to_can_execute_reverse ? \
1523       current_target.to_can_execute_reverse () : 0)
1524
1525 extern const struct target_desc *target_read_description (struct target_ops *);
1526
1527 #define target_get_ada_task_ptid(lwp, tid) \
1528      (*current_target.to_get_ada_task_ptid) (lwp,tid)
1529
1530 /* Utility implementation of searching memory.  */
1531 extern int simple_search_memory (struct target_ops* ops,
1532                                  CORE_ADDR start_addr,
1533                                  ULONGEST search_space_len,
1534                                  const gdb_byte *pattern,
1535                                  ULONGEST pattern_len,
1536                                  CORE_ADDR *found_addrp);
1537
1538 /* Main entry point for searching memory.  */
1539 extern int target_search_memory (CORE_ADDR start_addr,
1540                                  ULONGEST search_space_len,
1541                                  const gdb_byte *pattern,
1542                                  ULONGEST pattern_len,
1543                                  CORE_ADDR *found_addrp);
1544
1545 /* Target file operations.  */
1546
1547 /* Open FILENAME on the target, using FLAGS and MODE.  Return a
1548    target file descriptor, or -1 if an error occurs (and set
1549    *TARGET_ERRNO).  */
1550 extern int target_fileio_open (const char *filename, int flags, int mode,
1551                                int *target_errno);
1552
1553 /* Write up to LEN bytes from WRITE_BUF to FD on the target.
1554    Return the number of bytes written, or -1 if an error occurs
1555    (and set *TARGET_ERRNO).  */
1556 extern int target_fileio_pwrite (int fd, const gdb_byte *write_buf, int len,
1557                                  ULONGEST offset, int *target_errno);
1558
1559 /* Read up to LEN bytes FD on the target into READ_BUF.
1560    Return the number of bytes read, or -1 if an error occurs
1561    (and set *TARGET_ERRNO).  */
1562 extern int target_fileio_pread (int fd, gdb_byte *read_buf, int len,
1563                                 ULONGEST offset, int *target_errno);
1564
1565 /* Close FD on the target.  Return 0, or -1 if an error occurs
1566    (and set *TARGET_ERRNO).  */
1567 extern int target_fileio_close (int fd, int *target_errno);
1568
1569 /* Unlink FILENAME on the target.  Return 0, or -1 if an error
1570    occurs (and set *TARGET_ERRNO).  */
1571 extern int target_fileio_unlink (const char *filename, int *target_errno);
1572
1573 /* Read value of symbolic link FILENAME on the target.  Return a
1574    null-terminated string allocated via xmalloc, or NULL if an error
1575    occurs (and set *TARGET_ERRNO).  */
1576 extern char *target_fileio_readlink (const char *filename, int *target_errno);
1577
1578 /* Read target file FILENAME.  The return value will be -1 if the transfer
1579    fails or is not supported; 0 if the object is empty; or the length
1580    of the object otherwise.  If a positive value is returned, a
1581    sufficiently large buffer will be allocated using xmalloc and
1582    returned in *BUF_P containing the contents of the object.
1583
1584    This method should be used for objects sufficiently small to store
1585    in a single xmalloc'd buffer, when no fixed bound on the object's
1586    size is known in advance.  */
1587 extern LONGEST target_fileio_read_alloc (const char *filename,
1588                                          gdb_byte **buf_p);
1589
1590 /* Read target file FILENAME.  The result is NUL-terminated and
1591    returned as a string, allocated using xmalloc.  If an error occurs
1592    or the transfer is unsupported, NULL is returned.  Empty objects
1593    are returned as allocated but empty strings.  A warning is issued
1594    if the result contains any embedded NUL bytes.  */
1595 extern char *target_fileio_read_stralloc (const char *filename);
1596
1597
1598 /* Tracepoint-related operations.  */
1599
1600 #define target_trace_init() \
1601   (*current_target.to_trace_init) ()
1602
1603 #define target_download_tracepoint(t) \
1604   (*current_target.to_download_tracepoint) (t)
1605
1606 #define target_can_download_tracepoint() \
1607   (*current_target.to_can_download_tracepoint) ()
1608
1609 #define target_download_trace_state_variable(tsv) \
1610   (*current_target.to_download_trace_state_variable) (tsv)
1611
1612 #define target_enable_tracepoint(loc) \
1613   (*current_target.to_enable_tracepoint) (loc)
1614
1615 #define target_disable_tracepoint(loc) \
1616   (*current_target.to_disable_tracepoint) (loc)
1617
1618 #define target_trace_start() \
1619   (*current_target.to_trace_start) ()
1620
1621 #define target_trace_set_readonly_regions() \
1622   (*current_target.to_trace_set_readonly_regions) ()
1623
1624 #define target_get_trace_status(ts) \
1625   (*current_target.to_get_trace_status) (ts)
1626
1627 #define target_get_tracepoint_status(tp,utp)            \
1628   (*current_target.to_get_tracepoint_status) (tp, utp)
1629
1630 #define target_trace_stop() \
1631   (*current_target.to_trace_stop) ()
1632
1633 #define target_trace_find(type,num,addr1,addr2,tpp) \
1634   (*current_target.to_trace_find) ((type), (num), (addr1), (addr2), (tpp))
1635
1636 #define target_get_trace_state_variable_value(tsv,val) \
1637   (*current_target.to_get_trace_state_variable_value) ((tsv), (val))
1638
1639 #define target_save_trace_data(filename) \
1640   (*current_target.to_save_trace_data) (filename)
1641
1642 #define target_upload_tracepoints(utpp) \
1643   (*current_target.to_upload_tracepoints) (utpp)
1644
1645 #define target_upload_trace_state_variables(utsvp) \
1646   (*current_target.to_upload_trace_state_variables) (utsvp)
1647
1648 #define target_get_raw_trace_data(buf,offset,len) \
1649   (*current_target.to_get_raw_trace_data) ((buf), (offset), (len))
1650
1651 #define target_get_min_fast_tracepoint_insn_len() \
1652   (*current_target.to_get_min_fast_tracepoint_insn_len) ()
1653
1654 #define target_set_disconnected_tracing(val) \
1655   (*current_target.to_set_disconnected_tracing) (val)
1656
1657 #define target_set_circular_trace_buffer(val)   \
1658   (*current_target.to_set_circular_trace_buffer) (val)
1659
1660 #define target_set_trace_notes(user,notes,stopnotes)            \
1661   (*current_target.to_set_trace_notes) ((user), (notes), (stopnotes))
1662
1663 #define target_get_tib_address(ptid, addr) \
1664   (*current_target.to_get_tib_address) ((ptid), (addr))
1665
1666 #define target_set_permissions() \
1667   (*current_target.to_set_permissions) ()
1668
1669 #define target_static_tracepoint_marker_at(addr, marker) \
1670   (*current_target.to_static_tracepoint_marker_at) (addr, marker)
1671
1672 #define target_static_tracepoint_markers_by_strid(marker_id) \
1673   (*current_target.to_static_tracepoint_markers_by_strid) (marker_id)
1674
1675 #define target_traceframe_info() \
1676   (*current_target.to_traceframe_info) ()
1677
1678 /* Command logging facility.  */
1679
1680 #define target_log_command(p)                                           \
1681   do                                                                    \
1682     if (current_target.to_log_command)                                  \
1683       (*current_target.to_log_command) (p);                             \
1684   while (0)
1685
1686
1687 extern int target_core_of_thread (ptid_t ptid);
1688
1689 /* Verify that the memory in the [MEMADDR, MEMADDR+SIZE) range matches
1690    the contents of [DATA,DATA+SIZE).  Returns 1 if there's a match, 0
1691    if there's a mismatch, and -1 if an error is encountered while
1692    reading memory.  Throws an error if the functionality is found not
1693    to be supported by the current target.  */
1694 int target_verify_memory (const gdb_byte *data,
1695                           CORE_ADDR memaddr, ULONGEST size);
1696
1697 /* Routines for maintenance of the target structures...
1698
1699    add_target:   Add a target to the list of all possible targets.
1700
1701    push_target:  Make this target the top of the stack of currently used
1702    targets, within its particular stratum of the stack.  Result
1703    is 0 if now atop the stack, nonzero if not on top (maybe
1704    should warn user).
1705
1706    unpush_target: Remove this from the stack of currently used targets,
1707    no matter where it is on the list.  Returns 0 if no
1708    change, 1 if removed from stack.
1709
1710    pop_target:   Remove the top thing on the stack of current targets.  */
1711
1712 extern void add_target (struct target_ops *);
1713
1714 extern void push_target (struct target_ops *);
1715
1716 extern int unpush_target (struct target_ops *);
1717
1718 extern void target_pre_inferior (int);
1719
1720 extern void target_preopen (int);
1721
1722 extern void pop_target (void);
1723
1724 /* Does whatever cleanup is required to get rid of all pushed targets.
1725    QUITTING is propagated to target_close; it indicates that GDB is
1726    exiting and should not get hung on an error (otherwise it is
1727    important to perform clean termination, even if it takes a
1728    while).  */
1729 extern void pop_all_targets (int quitting);
1730
1731 /* Like pop_all_targets, but pops only targets whose stratum is
1732    strictly above ABOVE_STRATUM.  */
1733 extern void pop_all_targets_above (enum strata above_stratum, int quitting);
1734
1735 extern int target_is_pushed (struct target_ops *t);
1736
1737 extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
1738                                                CORE_ADDR offset);
1739
1740 /* Struct target_section maps address ranges to file sections.  It is
1741    mostly used with BFD files, but can be used without (e.g. for handling
1742    raw disks, or files not in formats handled by BFD).  */
1743
1744 struct target_section
1745   {
1746     CORE_ADDR addr;             /* Lowest address in section */
1747     CORE_ADDR endaddr;          /* 1+highest address in section */
1748
1749     struct bfd_section *the_bfd_section;
1750
1751     bfd *bfd;                   /* BFD file pointer */
1752   };
1753
1754 /* Holds an array of target sections.  Defined by [SECTIONS..SECTIONS_END[.  */
1755
1756 struct target_section_table
1757 {
1758   struct target_section *sections;
1759   struct target_section *sections_end;
1760 };
1761
1762 /* Return the "section" containing the specified address.  */
1763 struct target_section *target_section_by_addr (struct target_ops *target,
1764                                                CORE_ADDR addr);
1765
1766 /* Return the target section table this target (or the targets
1767    beneath) currently manipulate.  */
1768
1769 extern struct target_section_table *target_get_section_table
1770   (struct target_ops *target);
1771
1772 /* From mem-break.c */
1773
1774 extern int memory_remove_breakpoint (struct gdbarch *,
1775                                      struct bp_target_info *);
1776
1777 extern int memory_insert_breakpoint (struct gdbarch *,
1778                                      struct bp_target_info *);
1779
1780 extern int default_memory_remove_breakpoint (struct gdbarch *,
1781                                              struct bp_target_info *);
1782
1783 extern int default_memory_insert_breakpoint (struct gdbarch *,
1784                                              struct bp_target_info *);
1785
1786
1787 /* From target.c */
1788
1789 extern void initialize_targets (void);
1790
1791 extern void noprocess (void) ATTRIBUTE_NORETURN;
1792
1793 extern void target_require_runnable (void);
1794
1795 extern void find_default_attach (struct target_ops *, char *, int);
1796
1797 extern void find_default_create_inferior (struct target_ops *,
1798                                           char *, char *, char **, int);
1799
1800 extern struct target_ops *find_run_target (void);
1801
1802 extern struct target_ops *find_target_beneath (struct target_ops *);
1803
1804 /* Read OS data object of type TYPE from the target, and return it in
1805    XML format.  The result is NUL-terminated and returned as a string,
1806    allocated using xmalloc.  If an error occurs or the transfer is
1807    unsupported, NULL is returned.  Empty objects are returned as
1808    allocated but empty strings.  */
1809
1810 extern char *target_get_osdata (const char *type);
1811
1812 \f
1813 /* Stuff that should be shared among the various remote targets.  */
1814
1815 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1816    information (higher values, more information).  */
1817 extern int remote_debug;
1818
1819 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1820 extern int baud_rate;
1821 /* Timeout limit for response from target.  */
1822 extern int remote_timeout;
1823
1824 \f
1825 /* Functions for helping to write a native target.  */
1826
1827 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1828 extern void store_waitstatus (struct target_waitstatus *, int);
1829
1830 /* Set the show memory breakpoints mode to show, and installs a cleanup
1831    to restore it back to the current value.  */
1832 extern struct cleanup *make_show_memory_breakpoints_cleanup (int show);
1833
1834 extern int may_write_registers;
1835 extern int may_write_memory;
1836 extern int may_insert_breakpoints;
1837 extern int may_insert_tracepoints;
1838 extern int may_insert_fast_tracepoints;
1839 extern int may_stop;
1840
1841 extern void update_target_permissions (void);
1842
1843 \f
1844 /* Imported from machine dependent code.  */
1845
1846 /* Blank target vector entries are initialized to target_ignore.  */
1847 void target_ignore (void);
1848
1849 #endif /* !defined (TARGET_H) */