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