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, 2010, 2011
   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 struct trace_state_variable;
  35 struct trace_status;
  36 struct uploaded_tsv;
  37 struct uploaded_tp;
  38 struct static_tracepoint_marker;
  39
  40 struct expression;
  41
  42 /* This include file defines the interface between the main part
  43    of the debugger, and the part which is target-specific, or
  44    specific to the communications interface between us and the
  45    target.
  46
  47    A TARGET is an interface between the debugger and a particular
  48    kind of file or process.  Targets can be STACKED in STRATA,
  49    so that more than one target can potentially respond to a request.
  50    In particular, memory accesses will walk down the stack of targets
  51    until they find a target that is interested in handling that particular
  52    address.  STRATA are artificial boundaries on the stack, within
  53    which particular kinds of targets live.  Strata exist so that
  54    people don't get confused by pushing e.g. a process target and then
  55    a file target, and wondering why they can't see the current values
  56    of variables any more (the file target is handling them and they
  57    never get to the process target).  So when you push a file target,
  58    it goes into the file stratum, which is always below the process
  59    stratum.  */
  60
  61 #include "bfd.h"
  62 #include "symtab.h"
  63 #include "memattr.h"
  64 #include "vec.h"
  65 #include "gdb_signals.h"
  66
  67 enum strata
  68   {
  69     dummy_stratum,              /* The lowest of the low */
  70     file_stratum,               /* Executable files, etc */
  71     process_stratum,            /* Executing processes or core dump files */
  72     thread_stratum,             /* Executing threads */
  73     record_stratum,             /* Support record debugging */
  74     arch_stratum                /* Architecture overrides */
  75   };
  76
  77 enum thread_control_capabilities
  78   {
  79     tc_none = 0,                /* Default: can't control thread execution.  */
  80     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  81   };
  82
  83 /* Stuff for target_wait.  */
  84
  85 /* Generally, what has the program done?  */
  86 enum target_waitkind
  87   {
  88     /* The program has exited.  The exit status is in value.integer.  */
  89     TARGET_WAITKIND_EXITED,
  90
  91     /* The program has stopped with a signal.  Which signal is in
  92        value.sig.  */
  93     TARGET_WAITKIND_STOPPED,
  94
  95     /* The program has terminated with a signal.  Which signal is in
  96        value.sig.  */
  97     TARGET_WAITKIND_SIGNALLED,
  98
  99     /* The program is letting us know that it dynamically loaded something
 100        (e.g. it called load(2) on AIX).  */
 101     TARGET_WAITKIND_LOADED,
 102
 103     /* The program has forked.  A "related" process' PTID is in
 104        value.related_pid.  I.e., if the child forks, value.related_pid
 105        is the parent's ID.  */
 106
 107     TARGET_WAITKIND_FORKED,
 108
 109     /* The program has vforked.  A "related" process's PTID is in
 110        value.related_pid.  */
 111
 112     TARGET_WAITKIND_VFORKED,
 113
 114     /* The program has exec'ed a new executable file.  The new file's
 115        pathname is pointed to by value.execd_pathname.  */
 116
 117     TARGET_WAITKIND_EXECD,
 118
 119     /* The program had previously vforked, and now the child is done
 120        with the shared memory region, because it exec'ed or exited.
 121        Note that the event is reported to the vfork parent.  This is
 122        only used if GDB did not stay attached to the vfork child,
 123        otherwise, a TARGET_WAITKIND_EXECD or
 124        TARGET_WAITKIND_EXIT|SIGNALLED event associated with the child
 125        has the same effect.  */
 126     TARGET_WAITKIND_VFORK_DONE,
 127
 128     /* The program has entered or returned from a system call.  On
 129        HP-UX, this is used in the hardware watchpoint implementation.
 130        The syscall's unique integer ID number is in value.syscall_id.  */
 131
 132     TARGET_WAITKIND_SYSCALL_ENTRY,
 133     TARGET_WAITKIND_SYSCALL_RETURN,
 134
 135     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 136        within target_wait, but I'm not sure target_wait should be resuming the
 137        inferior.  */
 138     TARGET_WAITKIND_SPURIOUS,
 139
 140     /* An event has occured, but we should wait again.
 141        Remote_async_wait() returns this when there is an event
 142        on the inferior, but the rest of the world is not interested in
 143        it.  The inferior has not stopped, but has just sent some output
 144        to the console, for instance.  In this case, we want to go back
 145        to the event loop and wait there for another event from the
 146        inferior, rather than being stuck in the remote_async_wait()
 147        function. sThis way the event loop is responsive to other events,
 148        like for instance the user typing.  */
 149     TARGET_WAITKIND_IGNORE,
 150
 151     /* The target has run out of history information,
 152        and cannot run backward any further.  */
 153     TARGET_WAITKIND_NO_HISTORY
 154   };
 155
 156 struct target_waitstatus
 157   {
 158     enum target_waitkind kind;
 159
 160     /* Forked child pid, execd pathname, exit status, signal number or
 161        syscall number.  */
 162     union
 163       {
 164         int integer;
 165         enum target_signal sig;
 166         ptid_t related_pid;
 167         char *execd_pathname;
 168         int syscall_number;
 169       }
 170     value;
 171   };
 172
 173 /* Options that can be passed to target_wait.  */
 174
 175 /* Return immediately if there's no event already queued.  If this
 176    options is not requested, target_wait blocks waiting for an
 177    event.  */
 178 #define TARGET_WNOHANG 1
 179
 180 /* The structure below stores information about a system call.
 181    It is basically used in the "catch syscall" command, and in
 182    every function that gives information about a system call.
 183
 184    It's also good to mention that its fields represent everything
 185    that we currently know about a syscall in GDB.  */
 186 struct syscall
 187   {
 188     /* The syscall number.  */
 189     int number;
 190
 191     /* The syscall name.  */
 192     const char *name;
 193   };
 194
 195 /* Return a pretty printed form of target_waitstatus.
 196    Space for the result is malloc'd, caller must free.  */
 197 extern char *target_waitstatus_to_string (const struct target_waitstatus *);
 198
 199 /* Possible types of events that the inferior handler will have to
 200    deal with.  */
 201 enum inferior_event_type
 202   {
 203     /* There is a request to quit the inferior, abandon it.  */
 204     INF_QUIT_REQ,
 205     /* Process a normal inferior event which will result in target_wait
 206        being called.  */
 207     INF_REG_EVENT,
 208     /* Deal with an error on the inferior.  */
 209     INF_ERROR,
 210     /* We are called because a timer went off.  */
 211     INF_TIMER,
 212     /* We are called to do stuff after the inferior stops.  */
 213     INF_EXEC_COMPLETE,
 214     /* We are called to do some stuff after the inferior stops, but we
 215        are expected to reenter the proceed() and
 216        handle_inferior_event() functions.  This is used only in case of
 217        'step n' like commands.  */
 218     INF_EXEC_CONTINUE
 219   };
 220 \f
 221 /* Target objects which can be transfered using target_read,
 222    target_write, et cetera.  */
 223
 224 enum target_object
 225 {
 226   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 227   TARGET_OBJECT_AVR,
 228   /* SPU target specific transfer.  See "spu-tdep.c".  */
 229   TARGET_OBJECT_SPU,
 230   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 231   TARGET_OBJECT_MEMORY,
 232   /* Memory, avoiding GDB's data cache and trusting the executable.
 233      Target implementations of to_xfer_partial never need to handle
 234      this object, and most callers should not use it.  */
 235   TARGET_OBJECT_RAW_MEMORY,
 236   /* Memory known to be part of the target's stack.  This is cached even
 237      if it is not in a region marked as such, since it is known to be
 238      "normal" RAM.  */
 239   TARGET_OBJECT_STACK_MEMORY,
 240   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 241   TARGET_OBJECT_UNWIND_TABLE,
 242   /* Transfer auxilliary vector.  */
 243   TARGET_OBJECT_AUXV,
 244   /* StackGhost cookie.  See "sparc-tdep.c".  */
 245   TARGET_OBJECT_WCOOKIE,
 246   /* Target memory map in XML format.  */
 247   TARGET_OBJECT_MEMORY_MAP,
 248   /* Flash memory.  This object can be used to write contents to
 249      a previously erased flash memory.  Using it without erasing
 250      flash can have unexpected results.  Addresses are physical
 251      address on target, and not relative to flash start.  */
 252   TARGET_OBJECT_FLASH,
 253   /* Available target-specific features, e.g. registers and coprocessors.
 254      See "target-descriptions.c".  ANNEX should never be empty.  */
 255   TARGET_OBJECT_AVAILABLE_FEATURES,
 256   /* Currently loaded libraries, in XML format.  */
 257   TARGET_OBJECT_LIBRARIES,
 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   /* Possible future objects: TARGET_OBJECT_FILE, ...  */
 279 };
 280
 281 /* Enumeration of the kinds of traceframe searches that a target may
 282    be able to perform.  */
 283
 284 enum trace_find_type
 285   {
 286     tfind_number,
 287     tfind_pc,
 288     tfind_tp,
 289     tfind_range,
 290     tfind_outside,
 291   };
 292
 293 typedef struct static_tracepoint_marker *static_tracepoint_marker_p;
 294 DEF_VEC_P(static_tracepoint_marker_p);
 295
 296 /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 297    OBJECT.  The OFFSET, for a seekable object, specifies the
 298    starting point.  The ANNEX can be used to provide additional
 299    data-specific information to the target.
 300
 301    Return the number of bytes actually transfered, or -1 if the
 302    transfer is not supported or otherwise fails.  Return of a positive
 303    value less than LEN indicates that no further transfer is possible.
 304    Unlike the raw to_xfer_partial interface, callers of these
 305    functions do not need to retry partial transfers.  */
 306
 307 extern LONGEST target_read (struct target_ops *ops,
 308                             enum target_object object,
 309                             const char *annex, gdb_byte *buf,
 310                             ULONGEST offset, LONGEST len);
 311
 312 struct memory_read_result
 313   {
 314     /* First address that was read.  */
 315     ULONGEST begin;
 316     /* Past-the-end address.  */
 317     ULONGEST end;
 318     /* The data.  */
 319     gdb_byte *data;
 320 };
 321 typedef struct memory_read_result memory_read_result_s;
 322 DEF_VEC_O(memory_read_result_s);
 323
 324 extern void free_memory_read_result_vector (void *);
 325
 326 extern VEC(memory_read_result_s)* read_memory_robust (struct target_ops *ops,
 327                                                       ULONGEST offset,
 328                                                       LONGEST len);
 329
 330 extern LONGEST target_write (struct target_ops *ops,
 331                              enum target_object object,
 332                              const char *annex, const gdb_byte *buf,
 333                              ULONGEST offset, LONGEST len);
 334
 335 /* Similar to target_write, except that it also calls PROGRESS with
 336    the number of bytes written and the opaque BATON after every
 337    successful partial write (and before the first write).  This is
 338    useful for progress reporting and user interaction while writing
 339    data.  To abort the transfer, the progress callback can throw an
 340    exception.  */
 341
 342 LONGEST target_write_with_progress (struct target_ops *ops,
 343                                     enum target_object object,
 344                                     const char *annex, const gdb_byte *buf,
 345                                     ULONGEST offset, LONGEST len,
 346                                     void (*progress) (ULONGEST, void *),
 347                                     void *baton);
 348
 349 /* Wrapper to perform a full read of unknown size.  OBJECT/ANNEX will
 350    be read using OPS.  The return value will be -1 if the transfer
 351    fails or is not supported; 0 if the object is empty; or the length
 352    of the object otherwise.  If a positive value is returned, a
 353    sufficiently large buffer will be allocated using xmalloc and
 354    returned in *BUF_P containing the contents of the object.
 355
 356    This method should be used for objects sufficiently small to store
 357    in a single xmalloc'd buffer, when no fixed bound on the object's
 358    size is known in advance.  Don't try to read TARGET_OBJECT_MEMORY
 359    through this function.  */
 360
 361 extern LONGEST target_read_alloc (struct target_ops *ops,
 362                                   enum target_object object,
 363                                   const char *annex, gdb_byte **buf_p);
 364
 365 /* Read OBJECT/ANNEX using OPS.  The result is NUL-terminated and
 366    returned as a string, allocated using xmalloc.  If an error occurs
 367    or the transfer is unsupported, NULL is returned.  Empty objects
 368    are returned as allocated but empty strings.  A warning is issued
 369    if the result contains any embedded NUL bytes.  */
 370
 371 extern char *target_read_stralloc (struct target_ops *ops,
 372                                    enum target_object object,
 373                                    const char *annex);
 374
 375 /* Wrappers to target read/write that perform memory transfers.  They
 376    throw an error if the memory transfer fails.
 377
 378    NOTE: cagney/2003-10-23: The naming schema is lifted from
 379    "frame.h".  The parameter order is lifted from get_frame_memory,
 380    which in turn lifted it from read_memory.  */
 381
 382 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 383                                gdb_byte *buf, LONGEST len);
 384 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 385                                             CORE_ADDR addr, int len,
 386                                             enum bfd_endian byte_order);
 387 \f
 388 struct thread_info;             /* fwd decl for parameter list below: */
 389
 390 struct target_ops
 391   {
 392     struct target_ops *beneath; /* To the target under this one.  */
 393     char *to_shortname;         /* Name this target type */
 394     char *to_longname;          /* Name for printing */
 395     char *to_doc;               /* Documentation.  Does not include trailing
 396                                    newline, and starts with a one-line descrip-
 397                                    tion (probably similar to to_longname).  */
 398     /* Per-target scratch pad.  */
 399     void *to_data;
 400     /* The open routine takes the rest of the parameters from the
 401        command, and (if successful) pushes a new target onto the
 402        stack.  Targets should supply this routine, if only to provide
 403        an error message.  */
 404     void (*to_open) (char *, int);
 405     /* Old targets with a static target vector provide "to_close".
 406        New re-entrant targets provide "to_xclose" and that is expected
 407        to xfree everything (including the "struct target_ops").  */
 408     void (*to_xclose) (struct target_ops *targ, int quitting);
 409     void (*to_close) (int);
 410     void (*to_attach) (struct target_ops *ops, char *, int);
 411     void (*to_post_attach) (int);
 412     void (*to_detach) (struct target_ops *ops, char *, int);
 413     void (*to_disconnect) (struct target_ops *, char *, int);
 414     void (*to_resume) (struct target_ops *, ptid_t, int, enum target_signal);
 415     ptid_t (*to_wait) (struct target_ops *,
 416                        ptid_t, struct target_waitstatus *, int);
 417     void (*to_fetch_registers) (struct target_ops *, struct regcache *, int);
 418     void (*to_store_registers) (struct target_ops *, struct regcache *, int);
 419     void (*to_prepare_to_store) (struct regcache *);
 420
 421     /* Transfer LEN bytes of memory between GDB address MYADDR and
 422        target address MEMADDR.  If WRITE, transfer them to the target, else
 423        transfer them from the target.  TARGET is the target from which we
 424        get this function.
 425
 426        Return value, N, is one of the following:
 427
 428        0 means that we can't handle this.  If errno has been set, it is the
 429        error which prevented us from doing it (FIXME: What about bfd_error?).
 430
 431        positive (call it N) means that we have transferred N bytes
 432        starting at MEMADDR.  We might be able to handle more bytes
 433        beyond this length, but no promises.
 434
 435        negative (call its absolute value N) means that we cannot
 436        transfer right at MEMADDR, but we could transfer at least
 437        something at MEMADDR + N.
 438
 439        NOTE: cagney/2004-10-01: This has been entirely superseeded by
 440        to_xfer_partial and inferior inheritance.  */
 441
 442     int (*deprecated_xfer_memory) (CORE_ADDR memaddr, gdb_byte *myaddr,
 443                                    int len, int write,
 444                                    struct mem_attrib *attrib,
 445                                    struct target_ops *target);
 446
 447     void (*to_files_info) (struct target_ops *);
 448     int (*to_insert_breakpoint) (struct gdbarch *, struct bp_target_info *);
 449     int (*to_remove_breakpoint) (struct gdbarch *, struct bp_target_info *);
 450     int (*to_can_use_hw_breakpoint) (int, int, int);
 451     int (*to_insert_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 452     int (*to_remove_hw_breakpoint) (struct gdbarch *, struct bp_target_info *);
 453
 454     /* Documentation of what the two routines below are expected to do is
 455        provided with the corresponding target_* macros.  */
 456     int (*to_remove_watchpoint) (CORE_ADDR, int, int, struct expression *);
 457     int (*to_insert_watchpoint) (CORE_ADDR, int, int, struct expression *);
 458
 459     int (*to_stopped_by_watchpoint) (void);
 460     int to_have_steppable_watchpoint;
 461     int to_have_continuable_watchpoint;
 462     int (*to_stopped_data_address) (struct target_ops *, CORE_ADDR *);
 463     int (*to_watchpoint_addr_within_range) (struct target_ops *,
 464                                             CORE_ADDR, CORE_ADDR, int);
 465
 466     /* Documentation of this routine is provided with the corresponding
 467        target_* macro.  */
 468     int (*to_region_ok_for_hw_watchpoint) (CORE_ADDR, int);
 469
 470     int (*to_can_accel_watchpoint_condition) (CORE_ADDR, int, int,
 471                                               struct expression *);
 472     void (*to_terminal_init) (void);
 473     void (*to_terminal_inferior) (void);
 474     void (*to_terminal_ours_for_output) (void);
 475     void (*to_terminal_ours) (void);
 476     void (*to_terminal_save_ours) (void);
 477     void (*to_terminal_info) (char *, int);
 478     void (*to_kill) (struct target_ops *);
 479     void (*to_load) (char *, int);
 480     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 481     void (*to_create_inferior) (struct target_ops *,
 482                                 char *, char *, char **, int);
 483     void (*to_post_startup_inferior) (ptid_t);
 484     int (*to_insert_fork_catchpoint) (int);
 485     int (*to_remove_fork_catchpoint) (int);
 486     int (*to_insert_vfork_catchpoint) (int);
 487     int (*to_remove_vfork_catchpoint) (int);
 488     int (*to_follow_fork) (struct target_ops *, int);
 489     int (*to_insert_exec_catchpoint) (int);
 490     int (*to_remove_exec_catchpoint) (int);
 491     int (*to_set_syscall_catchpoint) (int, int, int, int, int *);
 492     int (*to_has_exited) (int, int, int *);
 493     void (*to_mourn_inferior) (struct target_ops *);
 494     int (*to_can_run) (void);
 495     void (*to_notice_signals) (ptid_t ptid);
 496     int (*to_thread_alive) (struct target_ops *, ptid_t ptid);
 497     void (*to_find_new_threads) (struct target_ops *);
 498     char *(*to_pid_to_str) (struct target_ops *, ptid_t);
 499     char *(*to_extra_thread_info) (struct thread_info *);
 500     void (*to_stop) (ptid_t);
 501     void (*to_rcmd) (char *command, struct ui_file *output);
 502     char *(*to_pid_to_exec_file) (int pid);
 503     void (*to_log_command) (const char *);
 504     struct target_section_table *(*to_get_section_table) (struct target_ops *);
 505     enum strata to_stratum;
 506     int (*to_has_all_memory) (struct target_ops *);
 507     int (*to_has_memory) (struct target_ops *);
 508     int (*to_has_stack) (struct target_ops *);
 509     int (*to_has_registers) (struct target_ops *);
 510     int (*to_has_execution) (struct target_ops *);
 511     int to_has_thread_control;  /* control thread execution */
 512     int to_attach_no_wait;
 513     /* ASYNC target controls */
 514     int (*to_can_async_p) (void);
 515     int (*to_is_async_p) (void);
 516     void (*to_async) (void (*) (enum inferior_event_type, void *), void *);
 517     int (*to_async_mask) (int);
 518     int (*to_supports_non_stop) (void);
 519     /* find_memory_regions support method for gcore */
 520     int (*to_find_memory_regions) (find_memory_region_ftype func, void *data);
 521     /* make_corefile_notes support method for gcore */
 522     char * (*to_make_corefile_notes) (bfd *, int *);
 523     /* get_bookmark support method for bookmarks */
 524     gdb_byte * (*to_get_bookmark) (char *, int);
 525     /* goto_bookmark support method for bookmarks */
 526     void (*to_goto_bookmark) (gdb_byte *, int);
 527     /* Return the thread-local address at OFFSET in the
 528        thread-local storage for the thread PTID and the shared library
 529        or executable file given by OBJFILE.  If that block of
 530        thread-local storage hasn't been allocated yet, this function
 531        may return an error.  */
 532     CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
 533                                               ptid_t ptid,
 534                                               CORE_ADDR load_module_addr,
 535                                               CORE_ADDR offset);
 536
 537     /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 538        OBJECT.  The OFFSET, for a seekable object, specifies the
 539        starting point.  The ANNEX can be used to provide additional
 540        data-specific information to the target.
 541
 542        Return the number of bytes actually transfered, zero when no
 543        further transfer is possible, and -1 when the transfer is not
 544        supported.  Return of a positive value smaller than LEN does
 545        not indicate the end of the object, only the end of the
 546        transfer; higher level code should continue transferring if
 547        desired.  This is handled in target.c.
 548
 549        The interface does not support a "retry" mechanism.  Instead it
 550        assumes that at least one byte will be transfered on each
 551        successful call.
 552
 553        NOTE: cagney/2003-10-17: The current interface can lead to
 554        fragmented transfers.  Lower target levels should not implement
 555        hacks, such as enlarging the transfer, in an attempt to
 556        compensate for this.  Instead, the target stack should be
 557        extended so that it implements supply/collect methods and a
 558        look-aside object cache.  With that available, the lowest
 559        target can safely and freely "push" data up the stack.
 560
 561        See target_read and target_write for more information.  One,
 562        and only one, of readbuf or writebuf must be non-NULL.  */
 563
 564     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 565                                 enum target_object object, const char *annex,
 566                                 gdb_byte *readbuf, const gdb_byte *writebuf,
 567                                 ULONGEST offset, LONGEST len);
 568
 569     /* Returns the memory map for the target.  A return value of NULL
 570        means that no memory map is available.  If a memory address
 571        does not fall within any returned regions, it's assumed to be
 572        RAM.  The returned memory regions should not overlap.
 573
 574        The order of regions does not matter; target_memory_map will
 575        sort regions by starting address.  For that reason, this
 576        function should not be called directly except via
 577        target_memory_map.
 578
 579        This method should not cache data; if the memory map could
 580        change unexpectedly, it should be invalidated, and higher
 581        layers will re-fetch it.  */
 582     VEC(mem_region_s) *(*to_memory_map) (struct target_ops *);
 583
 584     /* Erases the region of flash memory starting at ADDRESS, of
 585        length LENGTH.
 586
 587        Precondition: both ADDRESS and ADDRESS+LENGTH should be aligned
 588        on flash block boundaries, as reported by 'to_memory_map'.  */
 589     void (*to_flash_erase) (struct target_ops *,
 590                            ULONGEST address, LONGEST length);
 591
 592     /* Finishes a flash memory write sequence.  After this operation
 593        all flash memory should be available for writing and the result
 594        of reading from areas written by 'to_flash_write' should be
 595        equal to what was written.  */
 596     void (*to_flash_done) (struct target_ops *);
 597
 598     /* Describe the architecture-specific features of this target.
 599        Returns the description found, or NULL if no description
 600        was available.  */
 601     const struct target_desc *(*to_read_description) (struct target_ops *ops);
 602
 603     /* Build the PTID of the thread on which a given task is running,
 604        based on LWP and THREAD.  These values are extracted from the
 605        task Private_Data section of the Ada Task Control Block, and
 606        their interpretation depends on the target.  */
 607     ptid_t (*to_get_ada_task_ptid) (long lwp, long thread);
 608
 609     /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
 610        Return 0 if *READPTR is already at the end of the buffer.
 611        Return -1 if there is insufficient buffer for a whole entry.
 612        Return 1 if an entry was read into *TYPEP and *VALP.  */
 613     int (*to_auxv_parse) (struct target_ops *ops, gdb_byte **readptr,
 614                          gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 615
 616     /* Search SEARCH_SPACE_LEN bytes beginning at START_ADDR for the
 617        sequence of bytes in PATTERN with length PATTERN_LEN.
 618
 619        The result is 1 if found, 0 if not found, and -1 if there was an error
 620        requiring halting of the search (e.g. memory read error).
 621        If the pattern is found the address is recorded in FOUND_ADDRP.  */
 622     int (*to_search_memory) (struct target_ops *ops,
 623                              CORE_ADDR start_addr, ULONGEST search_space_len,
 624                              const gdb_byte *pattern, ULONGEST pattern_len,
 625                              CORE_ADDR *found_addrp);
 626
 627     /* Can target execute in reverse?  */
 628     int (*to_can_execute_reverse) (void);
 629
 630     /* Does this target support debugging multiple processes
 631        simultaneously?  */
 632     int (*to_supports_multi_process) (void);
 633
 634     /* Determine current architecture of thread PTID.
 635
 636        The target is supposed to determine the architecture of the code where
 637        the target is currently stopped at (on Cell, if a target is in spu_run,
 638        to_thread_architecture would return SPU, otherwise PPC32 or PPC64).
 639        This is architecture used to perform decr_pc_after_break adjustment,
 640        and also determines the frame architecture of the innermost frame.
 641        ptrace operations need to operate according to target_gdbarch.
 642
 643        The default implementation always returns target_gdbarch.  */
 644     struct gdbarch *(*to_thread_architecture) (struct target_ops *, ptid_t);
 645
 646     /* Determine current address space of thread PTID.
 647
 648        The default implementation always returns the inferior's
 649        address space.  */
 650     struct address_space *(*to_thread_address_space) (struct target_ops *,
 651                                                       ptid_t);
 652
 653     /* Tracepoint-related operations.  */
 654
 655     /* Prepare the target for a tracing run.  */
 656     void (*to_trace_init) (void);
 657
 658     /* Send full details of a tracepoint to the target.  */
 659     void (*to_download_tracepoint) (struct breakpoint *t);
 660
 661     /* Send full details of a trace state variable to the target.  */
 662     void (*to_download_trace_state_variable) (struct trace_state_variable *tsv);
 663
 664     /* Inform the target info of memory regions that are readonly
 665        (such as text sections), and so it should return data from
 666        those rather than look in the trace buffer.  */
 667     void (*to_trace_set_readonly_regions) (void);
 668
 669     /* Start a trace run.  */
 670     void (*to_trace_start) (void);
 671
 672     /* Get the current status of a tracing run.  */
 673     int (*to_get_trace_status) (struct trace_status *ts);
 674
 675     /* Stop a trace run.  */
 676     void (*to_trace_stop) (void);
 677
 678    /* Ask the target to find a trace frame of the given type TYPE,
 679       using NUM, ADDR1, and ADDR2 as search parameters.  Returns the
 680       number of the trace frame, and also the tracepoint number at
 681       TPP.  If no trace frame matches, return -1.  May throw if the
 682       operation fails.  */
 683     int (*to_trace_find) (enum trace_find_type type, int num,
 684                           ULONGEST addr1, ULONGEST addr2, int *tpp);
 685
 686     /* Get the value of the trace state variable number TSV, returning
 687        1 if the value is known and writing the value itself into the
 688        location pointed to by VAL, else returning 0.  */
 689     int (*to_get_trace_state_variable_value) (int tsv, LONGEST *val);
 690
 691     int (*to_save_trace_data) (const char *filename);
 692
 693     int (*to_upload_tracepoints) (struct uploaded_tp **utpp);
 694
 695     int (*to_upload_trace_state_variables) (struct uploaded_tsv **utsvp);
 696
 697     LONGEST (*to_get_raw_trace_data) (gdb_byte *buf,
 698                                       ULONGEST offset, LONGEST len);
 699
 700     /* Set the target's tracing behavior in response to unexpected
 701        disconnection - set VAL to 1 to keep tracing, 0 to stop.  */
 702     void (*to_set_disconnected_tracing) (int val);
 703     void (*to_set_circular_trace_buffer) (int val);
 704
 705     /* Return the processor core that thread PTID was last seen on.
 706        This information is updated only when:
 707        - update_thread_list is called
 708        - thread stops
 709        If the core cannot be determined -- either for the specified
 710        thread, or right now, or in this debug session, or for this
 711        target -- return -1.  */
 712     int (*to_core_of_thread) (struct target_ops *, ptid_t ptid);
 713
 714     /* Verify that the memory in the [MEMADDR, MEMADDR+SIZE) range
 715        matches the contents of [DATA,DATA+SIZE).  Returns 1 if there's
 716        a match, 0 if there's a mismatch, and -1 if an error is
 717        encountered while reading memory.  */
 718     int (*to_verify_memory) (struct target_ops *, const gdb_byte *data,
 719                              CORE_ADDR memaddr, ULONGEST size);
 720
 721     /* Return the address of the start of the Thread Information Block
 722        a Windows OS specific feature.  */
 723     int (*to_get_tib_address) (ptid_t ptid, CORE_ADDR *addr);
 724
 725     /* Send the new settings of write permission variables.  */
 726     void (*to_set_permissions) (void);
 727
 728     /* Look for a static tracepoint marker at ADDR, and fill in MARKER
 729        with its details.  Return 1 on success, 0 on failure.  */
 730     int (*to_static_tracepoint_marker_at) (CORE_ADDR,
 731                                            struct static_tracepoint_marker *marker);
 732
 733     /* Return a vector of all tracepoints markers string id ID, or all
 734        markers if ID is NULL.  */
 735     VEC(static_tracepoint_marker_p) *(*to_static_tracepoint_markers_by_strid)
 736       (const char *id);
 737
 738     int to_magic;
 739     /* Need sub-structure for target machine related rather than comm related?
 740      */
 741   };
 742
 743 /* Magic number for checking ops size.  If a struct doesn't end with this
 744    number, somebody changed the declaration but didn't change all the
 745    places that initialize one.  */
 746
 747 #define OPS_MAGIC       3840
 748
 749 /* The ops structure for our "current" target process.  This should
 750    never be NULL.  If there is no target, it points to the dummy_target.  */
 751
 752 extern struct target_ops current_target;
 753
 754 /* Define easy words for doing these operations on our current target.  */
 755
 756 #define target_shortname        (current_target.to_shortname)
 757 #define target_longname         (current_target.to_longname)
 758
 759 /* Does whatever cleanup is required for a target that we are no
 760    longer going to be calling.  QUITTING indicates that GDB is exiting
 761    and should not get hung on an error (otherwise it is important to
 762    perform clean termination, even if it takes a while).  This routine
 763    is automatically always called when popping the target off the
 764    target stack (to_beneath is undefined).  Closing file descriptors
 765    and freeing all memory allocated memory are typical things it
 766    should do.  */
 767
 768 void target_close (struct target_ops *targ, int quitting);
 769
 770 /* Attaches to a process on the target side.  Arguments are as passed
 771    to the `attach' command by the user.  This routine can be called
 772    when the target is not on the target-stack, if the target_can_run
 773    routine returns 1; in that case, it must push itself onto the stack.
 774    Upon exit, the target should be ready for normal operations, and
 775    should be ready to deliver the status of the process immediately
 776    (without waiting) to an upcoming target_wait call.  */
 777
 778 void target_attach (char *, int);
 779
 780 /* Some targets don't generate traps when attaching to the inferior,
 781    or their target_attach implementation takes care of the waiting.
 782    These targets must set to_attach_no_wait.  */
 783
 784 #define target_attach_no_wait \
 785      (current_target.to_attach_no_wait)
 786
 787 /* The target_attach operation places a process under debugger control,
 788    and stops the process.
 789
 790    This operation provides a target-specific hook that allows the
 791    necessary bookkeeping to be performed after an attach completes.  */
 792 #define target_post_attach(pid) \
 793      (*current_target.to_post_attach) (pid)
 794
 795 /* Takes a program previously attached to and detaches it.
 796    The program may resume execution (some targets do, some don't) and will
 797    no longer stop on signals, etc.  We better not have left any breakpoints
 798    in the program or it'll die when it hits one.  ARGS is arguments
 799    typed by the user (e.g. a signal to send the process).  FROM_TTY
 800    says whether to be verbose or not.  */
 801
 802 extern void target_detach (char *, int);
 803
 804 /* Disconnect from the current target without resuming it (leaving it
 805    waiting for a debugger).  */
 806
 807 extern void target_disconnect (char *, int);
 808
 809 /* Resume execution of the target process PTID.  STEP says whether to
 810    single-step or to run free; SIGGNAL is the signal to be given to
 811    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 812    pass TARGET_SIGNAL_DEFAULT.  */
 813
 814 extern void target_resume (ptid_t ptid, int step, enum target_signal signal);
 815
 816 /* Wait for process pid to do something.  PTID = -1 to wait for any
 817    pid to do something.  Return pid of child, or -1 in case of error;
 818    store status through argument pointer STATUS.  Note that it is
 819    _NOT_ OK to throw_exception() out of target_wait() without popping
 820    the debugging target from the stack; GDB isn't prepared to get back
 821    to the prompt with a debugging target but without the frame cache,
 822    stop_pc, etc., set up.  OPTIONS is a bitwise OR of TARGET_W*
 823    options.  */
 824
 825 extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status,
 826                            int options);
 827
 828 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 829
 830 extern void target_fetch_registers (struct regcache *regcache, int regno);
 831
 832 /* Store at least register REGNO, or all regs if REGNO == -1.
 833    It can store as many registers as it wants to, so target_prepare_to_store
 834    must have been previously called.  Calls error() if there are problems.  */
 835
 836 extern void target_store_registers (struct regcache *regcache, int regs);
 837
 838 /* Get ready to modify the registers array.  On machines which store
 839    individual registers, this doesn't need to do anything.  On machines
 840    which store all the registers in one fell swoop, this makes sure
 841    that REGISTERS contains all the registers from the program being
 842    debugged.  */
 843
 844 #define target_prepare_to_store(regcache)       \
 845      (*current_target.to_prepare_to_store) (regcache)
 846
 847 /* Determine current address space of thread PTID.  */
 848
 849 struct address_space *target_thread_address_space (ptid_t);
 850
 851 /* Returns true if this target can debug multiple processes
 852    simultaneously.  */
 853
 854 #define target_supports_multi_process() \
 855      (*current_target.to_supports_multi_process) ()
 856
 857 /* Invalidate all target dcaches.  */
 858 extern void target_dcache_invalidate (void);
 859
 860 extern int target_read_string (CORE_ADDR, char **, int, int *);
 861
 862 extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 863
 864 extern int target_read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 865
 866 extern int target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 867                                 int len);
 868
 869 /* Fetches the target's memory map.  If one is found it is sorted
 870    and returned, after some consistency checking.  Otherwise, NULL
 871    is returned.  */
 872 VEC(mem_region_s) *target_memory_map (void);
 873
 874 /* Erase the specified flash region.  */
 875 void target_flash_erase (ULONGEST address, LONGEST length);
 876
 877 /* Finish a sequence of flash operations.  */
 878 void target_flash_done (void);
 879
 880 /* Describes a request for a memory write operation.  */
 881 struct memory_write_request
 882   {
 883     /* Begining address that must be written.  */
 884     ULONGEST begin;
 885     /* Past-the-end address.  */
 886     ULONGEST end;
 887     /* The data to write.  */
 888     gdb_byte *data;
 889     /* A callback baton for progress reporting for this request.  */
 890     void *baton;
 891   };
 892 typedef struct memory_write_request memory_write_request_s;
 893 DEF_VEC_O(memory_write_request_s);
 894
 895 /* Enumeration specifying different flash preservation behaviour.  */
 896 enum flash_preserve_mode
 897   {
 898     flash_preserve,
 899     flash_discard
 900   };
 901
 902 /* Write several memory blocks at once.  This version can be more
 903    efficient than making several calls to target_write_memory, in
 904    particular because it can optimize accesses to flash memory.
 905
 906    Moreover, this is currently the only memory access function in gdb
 907    that supports writing to flash memory, and it should be used for
 908    all cases where access to flash memory is desirable.
 909
 910    REQUESTS is the vector (see vec.h) of memory_write_request.
 911    PRESERVE_FLASH_P indicates what to do with blocks which must be
 912      erased, but not completely rewritten.
 913    PROGRESS_CB is a function that will be periodically called to provide
 914      feedback to user.  It will be called with the baton corresponding
 915      to the request currently being written.  It may also be called
 916      with a NULL baton, when preserved flash sectors are being rewritten.
 917
 918    The function returns 0 on success, and error otherwise.  */
 919 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 920                                 enum flash_preserve_mode preserve_flash_p,
 921                                 void (*progress_cb) (ULONGEST, void *));
 922
 923 /* From infrun.c.  */
 924
 925 extern int inferior_has_forked (ptid_t pid, ptid_t *child_pid);
 926
 927 extern int inferior_has_vforked (ptid_t pid, ptid_t *child_pid);
 928
 929 extern int inferior_has_execd (ptid_t pid, char **execd_pathname);
 930
 931 extern int inferior_has_called_syscall (ptid_t pid, int *syscall_number);
 932
 933 /* Print a line about the current target.  */
 934
 935 #define target_files_info()     \
 936      (*current_target.to_files_info) (&current_target)
 937
 938 /* Insert a breakpoint at address BP_TGT->placed_address in the target
 939    machine.  Result is 0 for success, or an errno value.  */
 940
 941 extern int target_insert_breakpoint (struct gdbarch *gdbarch,
 942                                      struct bp_target_info *bp_tgt);
 943
 944 /* Remove a breakpoint at address BP_TGT->placed_address in the target
 945    machine.  Result is 0 for success, or an errno value.  */
 946
 947 extern int target_remove_breakpoint (struct gdbarch *gdbarch,
 948                                      struct bp_target_info *bp_tgt);
 949
 950 /* Initialize the terminal settings we record for the inferior,
 951    before we actually run the inferior.  */
 952
 953 #define target_terminal_init() \
 954      (*current_target.to_terminal_init) ()
 955
 956 /* Put the inferior's terminal settings into effect.
 957    This is preparation for starting or resuming the inferior.  */
 958
 959 extern void target_terminal_inferior (void);
 960
 961 /* Put some of our terminal settings into effect,
 962    enough to get proper results from our output,
 963    but do not change into or out of RAW mode
 964    so that no input is discarded.
 965
 966    After doing this, either terminal_ours or terminal_inferior
 967    should be called to get back to a normal state of affairs.  */
 968
 969 #define target_terminal_ours_for_output() \
 970      (*current_target.to_terminal_ours_for_output) ()
 971
 972 /* Put our terminal settings into effect.
 973    First record the inferior's terminal settings
 974    so they can be restored properly later.  */
 975
 976 #define target_terminal_ours() \
 977      (*current_target.to_terminal_ours) ()
 978
 979 /* Save our terminal settings.
 980    This is called from TUI after entering or leaving the curses
 981    mode.  Since curses modifies our terminal this call is here
 982    to take this change into account.  */
 983
 984 #define target_terminal_save_ours() \
 985      (*current_target.to_terminal_save_ours) ()
 986
 987 /* Print useful information about our terminal status, if such a thing
 988    exists.  */
 989
 990 #define target_terminal_info(arg, from_tty) \
 991      (*current_target.to_terminal_info) (arg, from_tty)
 992
 993 /* Kill the inferior process.   Make it go away.  */
 994
 995 extern void target_kill (void);
 996
 997 /* Load an executable file into the target process.  This is expected
 998    to not only bring new code into the target process, but also to
 999    update GDB's symbol tables to match.
1000
1001    ARG contains command-line arguments, to be broken down with
1002    buildargv ().  The first non-switch argument is the filename to
1003    load, FILE; the second is a number (as parsed by strtoul (..., ...,
1004    0)), which is an offset to apply to the load addresses of FILE's
1005    sections.  The target may define switches, or other non-switch
1006    arguments, as it pleases.  */
1007
1008 extern void target_load (char *arg, int from_tty);
1009
1010 /* Look up a symbol in the target's symbol table.  NAME is the symbol
1011    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
1012    symbol should be returned.  The result is 0 if successful, nonzero
1013    if the symbol does not exist in the target environment.  This
1014    function should not call error() if communication with the target
1015    is interrupted, since it is called from symbol reading, but should
1016    return nonzero, possibly doing a complain().  */
1017
1018 #define target_lookup_symbol(name, addrp) \
1019      (*current_target.to_lookup_symbol) (name, addrp)
1020
1021 /* Start an inferior process and set inferior_ptid to its pid.
1022    EXEC_FILE is the file to run.
1023    ALLARGS is a string containing the arguments to the program.
1024    ENV is the environment vector to pass.  Errors reported with error().
1025    On VxWorks and various standalone systems, we ignore exec_file.  */
1026
1027 void target_create_inferior (char *exec_file, char *args,
1028                              char **env, int from_tty);
1029
1030 /* Some targets (such as ttrace-based HPUX) don't allow us to request
1031    notification of inferior events such as fork and vork immediately
1032    after the inferior is created.  (This because of how gdb gets an
1033    inferior created via invoking a shell to do it.  In such a scenario,
1034    if the shell init file has commands in it, the shell will fork and
1035    exec for each of those commands, and we will see each such fork
1036    event.  Very bad.)
1037
1038    Such targets will supply an appropriate definition for this function.  */
1039
1040 #define target_post_startup_inferior(ptid) \
1041      (*current_target.to_post_startup_inferior) (ptid)
1042
1043 /* On some targets, we can catch an inferior fork or vfork event when
1044    it occurs.  These functions insert/remove an already-created
1045    catchpoint for such events.  They return  0 for success, 1 if the
1046    catchpoint type is not supported and -1 for failure.  */
1047
1048 #define target_insert_fork_catchpoint(pid) \
1049      (*current_target.to_insert_fork_catchpoint) (pid)
1050
1051 #define target_remove_fork_catchpoint(pid) \
1052      (*current_target.to_remove_fork_catchpoint) (pid)
1053
1054 #define target_insert_vfork_catchpoint(pid) \
1055      (*current_target.to_insert_vfork_catchpoint) (pid)
1056
1057 #define target_remove_vfork_catchpoint(pid) \
1058      (*current_target.to_remove_vfork_catchpoint) (pid)
1059
1060 /* If the inferior forks or vforks, this function will be called at
1061    the next resume in order to perform any bookkeeping and fiddling
1062    necessary to continue debugging either the parent or child, as
1063    requested, and releasing the other.  Information about the fork
1064    or vfork event is available via get_last_target_status ().
1065    This function returns 1 if the inferior should not be resumed
1066    (i.e. there is another event pending).  */
1067
1068 int target_follow_fork (int follow_child);
1069
1070 /* On some targets, we can catch an inferior exec event when it
1071    occurs.  These functions insert/remove an already-created
1072    catchpoint for such events.  They return  0 for success, 1 if the
1073    catchpoint type is not supported and -1 for failure.  */
1074
1075 #define target_insert_exec_catchpoint(pid) \
1076      (*current_target.to_insert_exec_catchpoint) (pid)
1077
1078 #define target_remove_exec_catchpoint(pid) \
1079      (*current_target.to_remove_exec_catchpoint) (pid)
1080
1081 /* Syscall catch.
1082
1083    NEEDED is nonzero if any syscall catch (of any kind) is requested.
1084    If NEEDED is zero, it means the target can disable the mechanism to
1085    catch system calls because there are no more catchpoints of this type.
1086
1087    ANY_COUNT is nonzero if a generic (filter-less) syscall catch is
1088    being requested.  In this case, both TABLE_SIZE and TABLE should
1089    be ignored.
1090
1091    TABLE_SIZE is the number of elements in TABLE.  It only matters if
1092    ANY_COUNT is zero.
1093
1094    TABLE is an array of ints, indexed by syscall number.  An element in
1095    this array is nonzero if that syscall should be caught.  This argument
1096    only matters if ANY_COUNT is zero.
1097
1098    Return 0 for success, 1 if syscall catchpoints are not supported or -1
1099    for failure.  */
1100
1101 #define target_set_syscall_catchpoint(pid, needed, any_count, table_size, table) \
1102      (*current_target.to_set_syscall_catchpoint) (pid, needed, any_count, \
1103                                                   table_size, table)
1104
1105 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
1106    exit code of PID, if any.  */
1107
1108 #define target_has_exited(pid,wait_status,exit_status) \
1109      (*current_target.to_has_exited) (pid,wait_status,exit_status)
1110
1111 /* The debugger has completed a blocking wait() call.  There is now
1112    some process event that must be processed.  This function should
1113    be defined by those targets that require the debugger to perform
1114    cleanup or internal state changes in response to the process event.  */
1115
1116 /* The inferior process has died.  Do what is right.  */
1117
1118 void target_mourn_inferior (void);
1119
1120 /* Does target have enough data to do a run or attach command? */
1121
1122 #define target_can_run(t) \
1123      ((t)->to_can_run) ()
1124
1125 /* post process changes to signal handling in the inferior.  */
1126
1127 #define target_notice_signals(ptid) \
1128      (*current_target.to_notice_signals) (ptid)
1129
1130 /* Check to see if a thread is still alive.  */
1131
1132 extern int target_thread_alive (ptid_t ptid);
1133
1134 /* Query for new threads and add them to the thread list.  */
1135
1136 extern void target_find_new_threads (void);
1137
1138 /* Make target stop in a continuable fashion.  (For instance, under
1139    Unix, this should act like SIGSTOP).  This function is normally
1140    used by GUIs to implement a stop button.  */
1141
1142 extern void target_stop (ptid_t ptid);
1143
1144 /* Send the specified COMMAND to the target's monitor
1145    (shell,interpreter) for execution.  The result of the query is
1146    placed in OUTBUF.  */
1147
1148 #define target_rcmd(command, outbuf) \
1149      (*current_target.to_rcmd) (command, outbuf)
1150
1151
1152 /* Does the target include all of memory, or only part of it?  This
1153    determines whether we look up the target chain for other parts of
1154    memory if this target can't satisfy a request.  */
1155
1156 extern int target_has_all_memory_1 (void);
1157 #define target_has_all_memory target_has_all_memory_1 ()
1158
1159 /* Does the target include memory?  (Dummy targets don't.)  */
1160
1161 extern int target_has_memory_1 (void);
1162 #define target_has_memory target_has_memory_1 ()
1163
1164 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
1165    we start a process.)  */
1166
1167 extern int target_has_stack_1 (void);
1168 #define target_has_stack target_has_stack_1 ()
1169
1170 /* Does the target have registers?  (Exec files don't.)  */
1171
1172 extern int target_has_registers_1 (void);
1173 #define target_has_registers target_has_registers_1 ()
1174
1175 /* Does the target have execution?  Can we make it jump (through
1176    hoops), or pop its stack a few times?  This means that the current
1177    target is currently executing; for some targets, that's the same as
1178    whether or not the target is capable of execution, but there are
1179    also targets which can be current while not executing.  In that
1180    case this will become true after target_create_inferior or
1181    target_attach.  */
1182
1183 extern int target_has_execution_1 (void);
1184 #define target_has_execution target_has_execution_1 ()
1185
1186 /* Default implementations for process_stratum targets.  Return true
1187    if there's a selected inferior, false otherwise.  */
1188
1189 extern int default_child_has_all_memory (struct target_ops *ops);
1190 extern int default_child_has_memory (struct target_ops *ops);
1191 extern int default_child_has_stack (struct target_ops *ops);
1192 extern int default_child_has_registers (struct target_ops *ops);
1193 extern int default_child_has_execution (struct target_ops *ops);
1194
1195 /* Can the target support the debugger control of thread execution?
1196    Can it lock the thread scheduler?  */
1197
1198 #define target_can_lock_scheduler \
1199      (current_target.to_has_thread_control & tc_schedlock)
1200
1201 /* Should the target enable async mode if it is supported?  Temporary
1202    cludge until async mode is a strict superset of sync mode.  */
1203 extern int target_async_permitted;
1204
1205 /* Can the target support asynchronous execution?  */
1206 #define target_can_async_p() (current_target.to_can_async_p ())
1207
1208 /* Is the target in asynchronous execution mode?  */
1209 #define target_is_async_p() (current_target.to_is_async_p ())
1210
1211 int target_supports_non_stop (void);
1212
1213 /* Put the target in async mode with the specified callback function.  */
1214 #define target_async(CALLBACK,CONTEXT) \
1215      (current_target.to_async ((CALLBACK), (CONTEXT)))
1216
1217 /* This is to be used ONLY within call_function_by_hand().  It provides
1218    a workaround, to have inferior function calls done in sychronous
1219    mode, even though the target is asynchronous.  After
1220    target_async_mask(0) is called, calls to target_can_async_p() will
1221    return FALSE , so that target_resume() will not try to start the
1222    target asynchronously.  After the inferior stops, we IMMEDIATELY
1223    restore the previous nature of the target, by calling
1224    target_async_mask(1).  After that, target_can_async_p() will return
1225    TRUE.  ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
1226
1227    FIXME ezannoni 1999-12-13: we won't need this once we move
1228    the turning async on and off to the single execution commands,
1229    from where it is done currently, in remote_resume().  */
1230
1231 #define target_async_mask(MASK) \
1232   (current_target.to_async_mask (MASK))
1233
1234 /* Converts a process id to a string.  Usually, the string just contains
1235    `process xyz', but on some systems it may contain
1236    `process xyz thread abc'.  */
1237
1238 extern char *target_pid_to_str (ptid_t ptid);
1239
1240 extern char *normal_pid_to_str (ptid_t ptid);
1241
1242 /* Return a short string describing extra information about PID,
1243    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1244    is okay.  */
1245
1246 #define target_extra_thread_info(TP) \
1247      (current_target.to_extra_thread_info (TP))
1248
1249 /* Attempts to find the pathname of the executable file
1250    that was run to create a specified process.
1251
1252    The process PID must be stopped when this operation is used.
1253
1254    If the executable file cannot be determined, NULL is returned.
1255
1256    Else, a pointer to a character string containing the pathname
1257    is returned.  This string should be copied into a buffer by
1258    the client if the string will not be immediately used, or if
1259    it must persist.  */
1260
1261 #define target_pid_to_exec_file(pid) \
1262      (current_target.to_pid_to_exec_file) (pid)
1263
1264 /* See the to_thread_architecture description in struct target_ops.  */
1265
1266 #define target_thread_architecture(ptid) \
1267      (current_target.to_thread_architecture (&current_target, ptid))
1268
1269 /*
1270  * Iterator function for target memory regions.
1271  * Calls a callback function once for each memory region 'mapped'
1272  * in the child process.  Defined as a simple macro rather than
1273  * as a function macro so that it can be tested for nullity.
1274  */
1275
1276 #define target_find_memory_regions(FUNC, DATA) \
1277      (current_target.to_find_memory_regions) (FUNC, DATA)
1278
1279 /*
1280  * Compose corefile .note section.
1281  */
1282
1283 #define target_make_corefile_notes(BFD, SIZE_P) \
1284      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
1285
1286 /* Bookmark interfaces.  */
1287 #define target_get_bookmark(ARGS, FROM_TTY) \
1288      (current_target.to_get_bookmark) (ARGS, FROM_TTY)
1289
1290 #define target_goto_bookmark(ARG, FROM_TTY) \
1291      (current_target.to_goto_bookmark) (ARG, FROM_TTY)
1292
1293 /* Hardware watchpoint interfaces.  */
1294
1295 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1296    write).  Only the INFERIOR_PTID task is being queried.  */
1297
1298 #define target_stopped_by_watchpoint \
1299    (*current_target.to_stopped_by_watchpoint)
1300
1301 /* Non-zero if we have steppable watchpoints  */
1302
1303 #define target_have_steppable_watchpoint \
1304    (current_target.to_have_steppable_watchpoint)
1305
1306 /* Non-zero if we have continuable watchpoints  */
1307
1308 #define target_have_continuable_watchpoint \
1309    (current_target.to_have_continuable_watchpoint)
1310
1311 /* Provide defaults for hardware watchpoint functions.  */
1312
1313 /* If the *_hw_beakpoint functions have not been defined
1314    elsewhere use the definitions in the target vector.  */
1315
1316 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1317    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1318    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1319    (including this one?).  OTHERTYPE is who knows what...  */
1320
1321 #define target_can_use_hardware_watchpoint(TYPE,CNT,OTHERTYPE) \
1322  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1323
1324 /* Returns the number of debug registers needed to watch the given
1325    memory region, or zero if not supported.  */
1326
1327 #define target_region_ok_for_hw_watchpoint(addr, len) \
1328     (*current_target.to_region_ok_for_hw_watchpoint) (addr, len)
1329
1330
1331 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.
1332    TYPE is 0 for write, 1 for read, and 2 for read/write accesses.
1333    COND is the expression for its condition, or NULL if there's none.
1334    Returns 0 for success, 1 if the watchpoint type is not supported,
1335    -1 for failure.  */
1336
1337 #define target_insert_watchpoint(addr, len, type, cond) \
1338      (*current_target.to_insert_watchpoint) (addr, len, type, cond)
1339
1340 #define target_remove_watchpoint(addr, len, type, cond) \
1341      (*current_target.to_remove_watchpoint) (addr, len, type, cond)
1342
1343 #define target_insert_hw_breakpoint(gdbarch, bp_tgt) \
1344      (*current_target.to_insert_hw_breakpoint) (gdbarch, bp_tgt)
1345
1346 #define target_remove_hw_breakpoint(gdbarch, bp_tgt) \
1347      (*current_target.to_remove_hw_breakpoint) (gdbarch, bp_tgt)
1348
1349 /* Return non-zero if target knows the data address which triggered this
1350    target_stopped_by_watchpoint, in such case place it to *ADDR_P.  Only the
1351    INFERIOR_PTID task is being queried.  */
1352 #define target_stopped_data_address(target, addr_p) \
1353     (*target.to_stopped_data_address) (target, addr_p)
1354
1355 #define target_watchpoint_addr_within_range(target, addr, start, length) \
1356   (*target.to_watchpoint_addr_within_range) (target, addr, start, length)
1357
1358 /* Return non-zero if the target is capable of using hardware to evaluate
1359    the condition expression.  In this case, if the condition is false when
1360    the watched memory location changes, execution may continue without the
1361    debugger being notified.
1362
1363    Due to limitations in the hardware implementation, it may be capable of
1364    avoiding triggering the watchpoint in some cases where the condition
1365    expression is false, but may report some false positives as well.
1366    For this reason, GDB will still evaluate the condition expression when
1367    the watchpoint triggers.  */
1368 #define target_can_accel_watchpoint_condition(addr, len, type, cond) \
1369   (*current_target.to_can_accel_watchpoint_condition) (addr, len, type, cond)
1370
1371 /* Target can execute in reverse?  */
1372 #define target_can_execute_reverse \
1373      (current_target.to_can_execute_reverse ? \
1374       current_target.to_can_execute_reverse () : 0)
1375
1376 extern const struct target_desc *target_read_description (struct target_ops *);
1377
1378 #define target_get_ada_task_ptid(lwp, tid) \
1379      (*current_target.to_get_ada_task_ptid) (lwp,tid)
1380
1381 /* Utility implementation of searching memory.  */
1382 extern int simple_search_memory (struct target_ops* ops,
1383                                  CORE_ADDR start_addr,
1384                                  ULONGEST search_space_len,
1385                                  const gdb_byte *pattern,
1386                                  ULONGEST pattern_len,
1387                                  CORE_ADDR *found_addrp);
1388
1389 /* Main entry point for searching memory.  */
1390 extern int target_search_memory (CORE_ADDR start_addr,
1391                                  ULONGEST search_space_len,
1392                                  const gdb_byte *pattern,
1393                                  ULONGEST pattern_len,
1394                                  CORE_ADDR *found_addrp);
1395
1396 /* Tracepoint-related operations.  */
1397
1398 #define target_trace_init() \
1399   (*current_target.to_trace_init) ()
1400
1401 #define target_download_tracepoint(t) \
1402   (*current_target.to_download_tracepoint) (t)
1403
1404 #define target_download_trace_state_variable(tsv) \
1405   (*current_target.to_download_trace_state_variable) (tsv)
1406
1407 #define target_trace_start() \
1408   (*current_target.to_trace_start) ()
1409
1410 #define target_trace_set_readonly_regions() \
1411   (*current_target.to_trace_set_readonly_regions) ()
1412
1413 #define target_get_trace_status(ts) \
1414   (*current_target.to_get_trace_status) (ts)
1415
1416 #define target_trace_stop() \
1417   (*current_target.to_trace_stop) ()
1418
1419 #define target_trace_find(type,num,addr1,addr2,tpp) \
1420   (*current_target.to_trace_find) ((type), (num), (addr1), (addr2), (tpp))
1421
1422 #define target_get_trace_state_variable_value(tsv,val) \
1423   (*current_target.to_get_trace_state_variable_value) ((tsv), (val))
1424
1425 #define target_save_trace_data(filename) \
1426   (*current_target.to_save_trace_data) (filename)
1427
1428 #define target_upload_tracepoints(utpp) \
1429   (*current_target.to_upload_tracepoints) (utpp)
1430
1431 #define target_upload_trace_state_variables(utsvp) \
1432   (*current_target.to_upload_trace_state_variables) (utsvp)
1433
1434 #define target_get_raw_trace_data(buf,offset,len) \
1435   (*current_target.to_get_raw_trace_data) ((buf), (offset), (len))
1436
1437 #define target_set_disconnected_tracing(val) \
1438   (*current_target.to_set_disconnected_tracing) (val)
1439
1440 #define target_set_circular_trace_buffer(val)   \
1441   (*current_target.to_set_circular_trace_buffer) (val)
1442
1443 #define target_get_tib_address(ptid, addr) \
1444   (*current_target.to_get_tib_address) ((ptid), (addr))
1445
1446 #define target_set_permissions() \
1447   (*current_target.to_set_permissions) ()
1448
1449 #define target_static_tracepoint_marker_at(addr, marker) \
1450   (*current_target.to_static_tracepoint_marker_at) (addr, marker)
1451
1452 #define target_static_tracepoint_markers_by_strid(marker_id) \
1453   (*current_target.to_static_tracepoint_markers_by_strid) (marker_id)
1454
1455 /* Command logging facility.  */
1456
1457 #define target_log_command(p)                                           \
1458   do                                                                    \
1459     if (current_target.to_log_command)                                  \
1460       (*current_target.to_log_command) (p);                             \
1461   while (0)
1462
1463
1464 extern int target_core_of_thread (ptid_t ptid);
1465
1466 /* Verify that the memory in the [MEMADDR, MEMADDR+SIZE) range matches
1467    the contents of [DATA,DATA+SIZE).  Returns 1 if there's a match, 0
1468    if there's a mismatch, and -1 if an error is encountered while
1469    reading memory.  Throws an error if the functionality is found not
1470    to be supported by the current target.  */
1471 int target_verify_memory (const gdb_byte *data,
1472                           CORE_ADDR memaddr, ULONGEST size);
1473
1474 /* Routines for maintenance of the target structures...
1475
1476    add_target:   Add a target to the list of all possible targets.
1477
1478    push_target:  Make this target the top of the stack of currently used
1479    targets, within its particular stratum of the stack.  Result
1480    is 0 if now atop the stack, nonzero if not on top (maybe
1481    should warn user).
1482
1483    unpush_target: Remove this from the stack of currently used targets,
1484    no matter where it is on the list.  Returns 0 if no
1485    change, 1 if removed from stack.
1486
1487    pop_target:   Remove the top thing on the stack of current targets.  */
1488
1489 extern void add_target (struct target_ops *);
1490
1491 extern void push_target (struct target_ops *);
1492
1493 extern int unpush_target (struct target_ops *);
1494
1495 extern void target_pre_inferior (int);
1496
1497 extern void target_preopen (int);
1498
1499 extern void pop_target (void);
1500
1501 /* Does whatever cleanup is required to get rid of all pushed targets.
1502    QUITTING is propagated to target_close; it indicates that GDB is
1503    exiting and should not get hung on an error (otherwise it is
1504    important to perform clean termination, even if it takes a
1505    while).  */
1506 extern void pop_all_targets (int quitting);
1507
1508 /* Like pop_all_targets, but pops only targets whose stratum is
1509    strictly above ABOVE_STRATUM.  */
1510 extern void pop_all_targets_above (enum strata above_stratum, int quitting);
1511
1512 extern int target_is_pushed (struct target_ops *t);
1513
1514 extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
1515                                                CORE_ADDR offset);
1516
1517 /* Struct target_section maps address ranges to file sections.  It is
1518    mostly used with BFD files, but can be used without (e.g. for handling
1519    raw disks, or files not in formats handled by BFD).  */
1520
1521 struct target_section
1522   {
1523     CORE_ADDR addr;             /* Lowest address in section */
1524     CORE_ADDR endaddr;          /* 1+highest address in section */
1525
1526     struct bfd_section *the_bfd_section;
1527
1528     bfd *bfd;                   /* BFD file pointer */
1529   };
1530
1531 /* Holds an array of target sections.  Defined by [SECTIONS..SECTIONS_END[.  */
1532
1533 struct target_section_table
1534 {
1535   struct target_section *sections;
1536   struct target_section *sections_end;
1537 };
1538
1539 /* Return the "section" containing the specified address.  */
1540 struct target_section *target_section_by_addr (struct target_ops *target,
1541                                                CORE_ADDR addr);
1542
1543 /* Return the target section table this target (or the targets
1544    beneath) currently manipulate.  */
1545
1546 extern struct target_section_table *target_get_section_table
1547   (struct target_ops *target);
1548
1549 /* From mem-break.c */
1550
1551 extern int memory_remove_breakpoint (struct gdbarch *,
1552                                      struct bp_target_info *);
1553
1554 extern int memory_insert_breakpoint (struct gdbarch *,
1555                                      struct bp_target_info *);
1556
1557 extern int default_memory_remove_breakpoint (struct gdbarch *,
1558                                              struct bp_target_info *);
1559
1560 extern int default_memory_insert_breakpoint (struct gdbarch *,
1561                                              struct bp_target_info *);
1562
1563
1564 /* From target.c */
1565
1566 extern void initialize_targets (void);
1567
1568 extern void noprocess (void) ATTRIBUTE_NORETURN;
1569
1570 extern void target_require_runnable (void);
1571
1572 extern void find_default_attach (struct target_ops *, char *, int);
1573
1574 extern void find_default_create_inferior (struct target_ops *,
1575                                           char *, char *, char **, int);
1576
1577 extern struct target_ops *find_run_target (void);
1578
1579 extern struct target_ops *find_target_beneath (struct target_ops *);
1580
1581 /* Read OS data object of type TYPE from the target, and return it in
1582    XML format.  The result is NUL-terminated and returned as a string,
1583    allocated using xmalloc.  If an error occurs or the transfer is
1584    unsupported, NULL is returned.  Empty objects are returned as
1585    allocated but empty strings.  */
1586
1587 extern char *target_get_osdata (const char *type);
1588
1589 \f
1590 /* Stuff that should be shared among the various remote targets.  */
1591
1592 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1593    information (higher values, more information).  */
1594 extern int remote_debug;
1595
1596 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1597 extern int baud_rate;
1598 /* Timeout limit for response from target.  */
1599 extern int remote_timeout;
1600
1601 \f
1602 /* Functions for helping to write a native target.  */
1603
1604 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1605 extern void store_waitstatus (struct target_waitstatus *, int);
1606
1607 /* These are in common/signals.c, but they're only used by gdb.  */
1608 extern enum target_signal default_target_signal_from_host (struct gdbarch *,
1609                                                            int);
1610 extern int default_target_signal_to_host (struct gdbarch *,
1611                                           enum target_signal);
1612
1613 /* Convert from a number used in a GDB command to an enum target_signal.  */
1614 extern enum target_signal target_signal_from_command (int);
1615 /* End of files in common/signals.c.  */
1616
1617 /* Set the show memory breakpoints mode to show, and installs a cleanup
1618    to restore it back to the current value.  */
1619 extern struct cleanup *make_show_memory_breakpoints_cleanup (int show);
1620
1621 extern int may_write_registers;
1622 extern int may_write_memory;
1623 extern int may_insert_breakpoints;
1624 extern int may_insert_tracepoints;
1625 extern int may_insert_fast_tracepoints;
1626 extern int may_stop;
1627
1628 extern void update_target_permissions (void);
1629
1630 \f
1631 /* Imported from machine dependent code.  */
1632
1633 /* Blank target vector entries are initialized to target_ignore.  */
1634 void target_ignore (void);
1635
1636 #endif /* !defined (TARGET_H) */