gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2
   3    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   5    Free Software Foundation, Inc.
   6
   7    Contributed by Cygnus Support.  Written by John Gilmore.
   8
   9    This file is part of GDB.
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  23
  24 #if !defined (TARGET_H)
  25 #define TARGET_H
  26
  27 struct objfile;
  28 struct ui_file;
  29 struct mem_attrib;
  30 struct target_ops;
  31 struct bp_target_info;
  32 struct regcache;
  33
  34 /* This include file defines the interface between the main part
  35    of the debugger, and the part which is target-specific, or
  36    specific to the communications interface between us and the
  37    target.
  38
  39    A TARGET is an interface between the debugger and a particular
  40    kind of file or process.  Targets can be STACKED in STRATA,
  41    so that more than one target can potentially respond to a request.
  42    In particular, memory accesses will walk down the stack of targets
  43    until they find a target that is interested in handling that particular
  44    address.  STRATA are artificial boundaries on the stack, within
  45    which particular kinds of targets live.  Strata exist so that
  46    people don't get confused by pushing e.g. a process target and then
  47    a file target, and wondering why they can't see the current values
  48    of variables any more (the file target is handling them and they
  49    never get to the process target).  So when you push a file target,
  50    it goes into the file stratum, which is always below the process
  51    stratum.  */
  52
  53 #include "bfd.h"
  54 #include "symtab.h"
  55 #include "dcache.h"
  56 #include "memattr.h"
  57 #include "vec.h"
  58 #include "gdb_signals.h"
  59
  60 enum strata
  61   {
  62     dummy_stratum,              /* The lowest of the low */
  63     file_stratum,               /* Executable files, etc */
  64     core_stratum,               /* Core dump files */
  65     process_stratum,            /* Executing processes */
  66     thread_stratum              /* Executing threads */
  67   };
  68
  69 enum thread_control_capabilities
  70   {
  71     tc_none = 0,                /* Default: can't control thread execution.  */
  72     tc_schedlock = 1,           /* Can lock the thread scheduler.  */
  73   };
  74
  75 /* Stuff for target_wait.  */
  76
  77 /* Generally, what has the program done?  */
  78 enum target_waitkind
  79   {
  80     /* The program has exited.  The exit status is in value.integer.  */
  81     TARGET_WAITKIND_EXITED,
  82
  83     /* The program has stopped with a signal.  Which signal is in
  84        value.sig.  */
  85     TARGET_WAITKIND_STOPPED,
  86
  87     /* The program has terminated with a signal.  Which signal is in
  88        value.sig.  */
  89     TARGET_WAITKIND_SIGNALLED,
  90
  91     /* The program is letting us know that it dynamically loaded something
  92        (e.g. it called load(2) on AIX).  */
  93     TARGET_WAITKIND_LOADED,
  94
  95     /* The program has forked.  A "related" process' PTID is in
  96        value.related_pid.  I.e., if the child forks, value.related_pid
  97        is the parent's ID.  */
  98
  99     TARGET_WAITKIND_FORKED,
 100
 101     /* The program has vforked.  A "related" process's PTID is in
 102        value.related_pid.  */
 103
 104     TARGET_WAITKIND_VFORKED,
 105
 106     /* The program has exec'ed a new executable file.  The new file's
 107        pathname is pointed to by value.execd_pathname.  */
 108
 109     TARGET_WAITKIND_EXECD,
 110
 111     /* The program has entered or returned from a system call.  On
 112        HP-UX, this is used in the hardware watchpoint implementation.
 113        The syscall's unique integer ID number is in value.syscall_id */
 114
 115     TARGET_WAITKIND_SYSCALL_ENTRY,
 116     TARGET_WAITKIND_SYSCALL_RETURN,
 117
 118     /* Nothing happened, but we stopped anyway.  This perhaps should be handled
 119        within target_wait, but I'm not sure target_wait should be resuming the
 120        inferior.  */
 121     TARGET_WAITKIND_SPURIOUS,
 122
 123     /* An event has occured, but we should wait again.
 124        Remote_async_wait() returns this when there is an event
 125        on the inferior, but the rest of the world is not interested in
 126        it. The inferior has not stopped, but has just sent some output
 127        to the console, for instance. In this case, we want to go back
 128        to the event loop and wait there for another event from the
 129        inferior, rather than being stuck in the remote_async_wait()
 130        function. This way the event loop is responsive to other events,
 131        like for instance the user typing.  */
 132     TARGET_WAITKIND_IGNORE,
 133
 134     /* The target has run out of history information,
 135        and cannot run backward any further.  */
 136     TARGET_WAITKIND_NO_HISTORY
 137   };
 138
 139 struct target_waitstatus
 140   {
 141     enum target_waitkind kind;
 142
 143     /* Forked child pid, execd pathname, exit status or signal number.  */
 144     union
 145       {
 146         int integer;
 147         enum target_signal sig;
 148         ptid_t related_pid;
 149         char *execd_pathname;
 150         int syscall_id;
 151       }
 152     value;
 153   };
 154
 155 /* Return a pretty printed form of target_waitstatus.
 156    Space for the result is malloc'd, caller must free.  */
 157 extern char *target_waitstatus_to_string (const struct target_waitstatus *);
 158
 159 /* Possible types of events that the inferior handler will have to
 160    deal with.  */
 161 enum inferior_event_type
 162   {
 163     /* There is a request to quit the inferior, abandon it.  */
 164     INF_QUIT_REQ,
 165     /* Process a normal inferior event which will result in target_wait
 166        being called.  */
 167     INF_REG_EVENT,
 168     /* Deal with an error on the inferior.  */
 169     INF_ERROR,
 170     /* We are called because a timer went off.  */
 171     INF_TIMER,
 172     /* We are called to do stuff after the inferior stops.  */
 173     INF_EXEC_COMPLETE,
 174     /* We are called to do some stuff after the inferior stops, but we
 175        are expected to reenter the proceed() and
 176        handle_inferior_event() functions. This is used only in case of
 177        'step n' like commands.  */
 178     INF_EXEC_CONTINUE
 179   };
 180 \f
 181 /* Target objects which can be transfered using target_read,
 182    target_write, et cetera.  */
 183
 184 enum target_object
 185 {
 186   /* AVR target specific transfer.  See "avr-tdep.c" and "remote.c".  */
 187   TARGET_OBJECT_AVR,
 188   /* SPU target specific transfer.  See "spu-tdep.c".  */
 189   TARGET_OBJECT_SPU,
 190   /* Transfer up-to LEN bytes of memory starting at OFFSET.  */
 191   TARGET_OBJECT_MEMORY,
 192   /* Memory, avoiding GDB's data cache and trusting the executable.
 193      Target implementations of to_xfer_partial never need to handle
 194      this object, and most callers should not use it.  */
 195   TARGET_OBJECT_RAW_MEMORY,
 196   /* Kernel Unwind Table.  See "ia64-tdep.c".  */
 197   TARGET_OBJECT_UNWIND_TABLE,
 198   /* Transfer auxilliary vector.  */
 199   TARGET_OBJECT_AUXV,
 200   /* StackGhost cookie.  See "sparc-tdep.c".  */
 201   TARGET_OBJECT_WCOOKIE,
 202   /* Target memory map in XML format.  */
 203   TARGET_OBJECT_MEMORY_MAP,
 204   /* Flash memory.  This object can be used to write contents to
 205      a previously erased flash memory.  Using it without erasing
 206      flash can have unexpected results.  Addresses are physical
 207      address on target, and not relative to flash start.  */
 208   TARGET_OBJECT_FLASH,
 209   /* Available target-specific features, e.g. registers and coprocessors.
 210      See "target-descriptions.c".  ANNEX should never be empty.  */
 211   TARGET_OBJECT_AVAILABLE_FEATURES,
 212   /* Currently loaded libraries, in XML format.  */
 213   TARGET_OBJECT_LIBRARIES,
 214   /* Get OS specific data.  The ANNEX specifies the type (running
 215      processes, etc.).  */
 216   TARGET_OBJECT_OSDATA,
 217   /* Extra signal info.  Usually the contents of `siginfo_t' on unix
 218      platforms.  */
 219   TARGET_OBJECT_SIGNAL_INFO,
 220   /* Possible future objects: TARGET_OBJECT_FILE, ... */
 221 };
 222
 223 /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 224    OBJECT.  The OFFSET, for a seekable object, specifies the
 225    starting point.  The ANNEX can be used to provide additional
 226    data-specific information to the target.
 227
 228    Return the number of bytes actually transfered, or -1 if the
 229    transfer is not supported or otherwise fails.  Return of a positive
 230    value less than LEN indicates that no further transfer is possible.
 231    Unlike the raw to_xfer_partial interface, callers of these
 232    functions do not need to retry partial transfers.  */
 233
 234 extern LONGEST target_read (struct target_ops *ops,
 235                             enum target_object object,
 236                             const char *annex, gdb_byte *buf,
 237                             ULONGEST offset, LONGEST len);
 238
 239 extern LONGEST target_read_until_error (struct target_ops *ops,
 240                                         enum target_object object,
 241                                         const char *annex, gdb_byte *buf,
 242                                         ULONGEST offset, LONGEST len);
 243
 244 extern LONGEST target_write (struct target_ops *ops,
 245                              enum target_object object,
 246                              const char *annex, const gdb_byte *buf,
 247                              ULONGEST offset, LONGEST len);
 248
 249 /* Similar to target_write, except that it also calls PROGRESS with
 250    the number of bytes written and the opaque BATON after every
 251    successful partial write (and before the first write).  This is
 252    useful for progress reporting and user interaction while writing
 253    data.  To abort the transfer, the progress callback can throw an
 254    exception.  */
 255
 256 LONGEST target_write_with_progress (struct target_ops *ops,
 257                                     enum target_object object,
 258                                     const char *annex, const gdb_byte *buf,
 259                                     ULONGEST offset, LONGEST len,
 260                                     void (*progress) (ULONGEST, void *),
 261                                     void *baton);
 262
 263 /* Wrapper to perform a full read of unknown size.  OBJECT/ANNEX will
 264    be read using OPS.  The return value will be -1 if the transfer
 265    fails or is not supported; 0 if the object is empty; or the length
 266    of the object otherwise.  If a positive value is returned, a
 267    sufficiently large buffer will be allocated using xmalloc and
 268    returned in *BUF_P containing the contents of the object.
 269
 270    This method should be used for objects sufficiently small to store
 271    in a single xmalloc'd buffer, when no fixed bound on the object's
 272    size is known in advance.  Don't try to read TARGET_OBJECT_MEMORY
 273    through this function.  */
 274
 275 extern LONGEST target_read_alloc (struct target_ops *ops,
 276                                   enum target_object object,
 277                                   const char *annex, gdb_byte **buf_p);
 278
 279 /* Read OBJECT/ANNEX using OPS.  The result is NUL-terminated and
 280    returned as a string, allocated using xmalloc.  If an error occurs
 281    or the transfer is unsupported, NULL is returned.  Empty objects
 282    are returned as allocated but empty strings.  A warning is issued
 283    if the result contains any embedded NUL bytes.  */
 284
 285 extern char *target_read_stralloc (struct target_ops *ops,
 286                                    enum target_object object,
 287                                    const char *annex);
 288
 289 /* Wrappers to target read/write that perform memory transfers.  They
 290    throw an error if the memory transfer fails.
 291
 292    NOTE: cagney/2003-10-23: The naming schema is lifted from
 293    "frame.h".  The parameter order is lifted from get_frame_memory,
 294    which in turn lifted it from read_memory.  */
 295
 296 extern void get_target_memory (struct target_ops *ops, CORE_ADDR addr,
 297                                gdb_byte *buf, LONGEST len);
 298 extern ULONGEST get_target_memory_unsigned (struct target_ops *ops,
 299                                             CORE_ADDR addr, int len);
 300 \f
 301 struct thread_info;             /* fwd decl for parameter list below: */
 302
 303 struct target_ops
 304   {
 305     struct target_ops *beneath; /* To the target under this one.  */
 306     char *to_shortname;         /* Name this target type */
 307     char *to_longname;          /* Name for printing */
 308     char *to_doc;               /* Documentation.  Does not include trailing
 309                                    newline, and starts with a one-line descrip-
 310                                    tion (probably similar to to_longname).  */
 311     /* Per-target scratch pad.  */
 312     void *to_data;
 313     /* The open routine takes the rest of the parameters from the
 314        command, and (if successful) pushes a new target onto the
 315        stack.  Targets should supply this routine, if only to provide
 316        an error message.  */
 317     void (*to_open) (char *, int);
 318     /* Old targets with a static target vector provide "to_close".
 319        New re-entrant targets provide "to_xclose" and that is expected
 320        to xfree everything (including the "struct target_ops").  */
 321     void (*to_xclose) (struct target_ops *targ, int quitting);
 322     void (*to_close) (int);
 323     void (*to_attach) (struct target_ops *ops, char *, int);
 324     void (*to_post_attach) (int);
 325     void (*to_detach) (struct target_ops *ops, char *, int);
 326     void (*to_disconnect) (struct target_ops *, char *, int);
 327     void (*to_resume) (struct target_ops *, ptid_t, int, enum target_signal);
 328     ptid_t (*to_wait) (struct target_ops *,
 329                       ptid_t, struct target_waitstatus *);
 330     void (*to_fetch_registers) (struct target_ops *, struct regcache *, int);
 331     void (*to_store_registers) (struct target_ops *, struct regcache *, int);
 332     void (*to_prepare_to_store) (struct regcache *);
 333
 334     /* Transfer LEN bytes of memory between GDB address MYADDR and
 335        target address MEMADDR.  If WRITE, transfer them to the target, else
 336        transfer them from the target.  TARGET is the target from which we
 337        get this function.
 338
 339        Return value, N, is one of the following:
 340
 341        0 means that we can't handle this.  If errno has been set, it is the
 342        error which prevented us from doing it (FIXME: What about bfd_error?).
 343
 344        positive (call it N) means that we have transferred N bytes
 345        starting at MEMADDR.  We might be able to handle more bytes
 346        beyond this length, but no promises.
 347
 348        negative (call its absolute value N) means that we cannot
 349        transfer right at MEMADDR, but we could transfer at least
 350        something at MEMADDR + N.
 351
 352        NOTE: cagney/2004-10-01: This has been entirely superseeded by
 353        to_xfer_partial and inferior inheritance.  */
 354
 355     int (*deprecated_xfer_memory) (CORE_ADDR memaddr, gdb_byte *myaddr,
 356                                    int len, int write,
 357                                    struct mem_attrib *attrib,
 358                                    struct target_ops *target);
 359
 360     void (*to_files_info) (struct target_ops *);
 361     int (*to_insert_breakpoint) (struct bp_target_info *);
 362     int (*to_remove_breakpoint) (struct bp_target_info *);
 363     int (*to_can_use_hw_breakpoint) (int, int, int);
 364     int (*to_insert_hw_breakpoint) (struct bp_target_info *);
 365     int (*to_remove_hw_breakpoint) (struct bp_target_info *);
 366     int (*to_remove_watchpoint) (CORE_ADDR, int, int);
 367     int (*to_insert_watchpoint) (CORE_ADDR, int, int);
 368     int (*to_stopped_by_watchpoint) (void);
 369     int to_have_steppable_watchpoint;
 370     int to_have_continuable_watchpoint;
 371     int (*to_stopped_data_address) (struct target_ops *, CORE_ADDR *);
 372     int (*to_watchpoint_addr_within_range) (struct target_ops *,
 373                                             CORE_ADDR, CORE_ADDR, int);
 374     int (*to_region_ok_for_hw_watchpoint) (CORE_ADDR, int);
 375     void (*to_terminal_init) (void);
 376     void (*to_terminal_inferior) (void);
 377     void (*to_terminal_ours_for_output) (void);
 378     void (*to_terminal_ours) (void);
 379     void (*to_terminal_save_ours) (void);
 380     void (*to_terminal_info) (char *, int);
 381     void (*to_kill) (struct target_ops *);
 382     void (*to_load) (char *, int);
 383     int (*to_lookup_symbol) (char *, CORE_ADDR *);
 384     void (*to_create_inferior) (struct target_ops *,
 385                                 char *, char *, char **, int);
 386     void (*to_post_startup_inferior) (ptid_t);
 387     void (*to_acknowledge_created_inferior) (int);
 388     void (*to_insert_fork_catchpoint) (int);
 389     int (*to_remove_fork_catchpoint) (int);
 390     void (*to_insert_vfork_catchpoint) (int);
 391     int (*to_remove_vfork_catchpoint) (int);
 392     int (*to_follow_fork) (struct target_ops *, int);
 393     void (*to_insert_exec_catchpoint) (int);
 394     int (*to_remove_exec_catchpoint) (int);
 395     int (*to_has_exited) (int, int, int *);
 396     void (*to_mourn_inferior) (struct target_ops *);
 397     int (*to_can_run) (void);
 398     void (*to_notice_signals) (ptid_t ptid);
 399     int (*to_thread_alive) (struct target_ops *, ptid_t ptid);
 400     void (*to_find_new_threads) (struct target_ops *);
 401     char *(*to_pid_to_str) (struct target_ops *, ptid_t);
 402     char *(*to_extra_thread_info) (struct thread_info *);
 403     void (*to_stop) (ptid_t);
 404     void (*to_rcmd) (char *command, struct ui_file *output);
 405     char *(*to_pid_to_exec_file) (int pid);
 406     void (*to_log_command) (const char *);
 407     enum strata to_stratum;
 408     int to_has_all_memory;
 409     int to_has_memory;
 410     int to_has_stack;
 411     int to_has_registers;
 412     int to_has_execution;
 413     int to_has_thread_control;  /* control thread execution */
 414     int to_attach_no_wait;
 415     struct section_table
 416      *to_sections;
 417     struct section_table
 418      *to_sections_end;
 419     /* ASYNC target controls */
 420     int (*to_can_async_p) (void);
 421     int (*to_is_async_p) (void);
 422     void (*to_async) (void (*) (enum inferior_event_type, void *), void *);
 423     int (*to_async_mask) (int);
 424     int (*to_supports_non_stop) (void);
 425     int (*to_find_memory_regions) (int (*) (CORE_ADDR,
 426                                             unsigned long,
 427                                             int, int, int,
 428                                             void *),
 429                                    void *);
 430     char * (*to_make_corefile_notes) (bfd *, int *);
 431
 432     /* Return the thread-local address at OFFSET in the
 433        thread-local storage for the thread PTID and the shared library
 434        or executable file given by OBJFILE.  If that block of
 435        thread-local storage hasn't been allocated yet, this function
 436        may return an error.  */
 437     CORE_ADDR (*to_get_thread_local_address) (struct target_ops *ops,
 438                                               ptid_t ptid,
 439                                               CORE_ADDR load_module_addr,
 440                                               CORE_ADDR offset);
 441
 442     /* Request that OPS transfer up to LEN 8-bit bytes of the target's
 443        OBJECT.  The OFFSET, for a seekable object, specifies the
 444        starting point.  The ANNEX can be used to provide additional
 445        data-specific information to the target.
 446
 447        Return the number of bytes actually transfered, zero when no
 448        further transfer is possible, and -1 when the transfer is not
 449        supported.  Return of a positive value smaller than LEN does
 450        not indicate the end of the object, only the end of the
 451        transfer; higher level code should continue transferring if
 452        desired.  This is handled in target.c.
 453
 454        The interface does not support a "retry" mechanism.  Instead it
 455        assumes that at least one byte will be transfered on each
 456        successful call.
 457
 458        NOTE: cagney/2003-10-17: The current interface can lead to
 459        fragmented transfers.  Lower target levels should not implement
 460        hacks, such as enlarging the transfer, in an attempt to
 461        compensate for this.  Instead, the target stack should be
 462        extended so that it implements supply/collect methods and a
 463        look-aside object cache.  With that available, the lowest
 464        target can safely and freely "push" data up the stack.
 465
 466        See target_read and target_write for more information.  One,
 467        and only one, of readbuf or writebuf must be non-NULL.  */
 468
 469     LONGEST (*to_xfer_partial) (struct target_ops *ops,
 470                                 enum target_object object, const char *annex,
 471                                 gdb_byte *readbuf, const gdb_byte *writebuf,
 472                                 ULONGEST offset, LONGEST len);
 473
 474     /* Returns the memory map for the target.  A return value of NULL
 475        means that no memory map is available.  If a memory address
 476        does not fall within any returned regions, it's assumed to be
 477        RAM.  The returned memory regions should not overlap.
 478
 479        The order of regions does not matter; target_memory_map will
 480        sort regions by starting address. For that reason, this
 481        function should not be called directly except via
 482        target_memory_map.
 483
 484        This method should not cache data; if the memory map could
 485        change unexpectedly, it should be invalidated, and higher
 486        layers will re-fetch it.  */
 487     VEC(mem_region_s) *(*to_memory_map) (struct target_ops *);
 488
 489     /* Erases the region of flash memory starting at ADDRESS, of
 490        length LENGTH.
 491
 492        Precondition: both ADDRESS and ADDRESS+LENGTH should be aligned
 493        on flash block boundaries, as reported by 'to_memory_map'.  */
 494     void (*to_flash_erase) (struct target_ops *,
 495                            ULONGEST address, LONGEST length);
 496
 497     /* Finishes a flash memory write sequence.  After this operation
 498        all flash memory should be available for writing and the result
 499        of reading from areas written by 'to_flash_write' should be
 500        equal to what was written.  */
 501     void (*to_flash_done) (struct target_ops *);
 502
 503     /* Describe the architecture-specific features of this target.
 504        Returns the description found, or NULL if no description
 505        was available.  */
 506     const struct target_desc *(*to_read_description) (struct target_ops *ops);
 507
 508     /* Build the PTID of the thread on which a given task is running,
 509        based on LWP and THREAD.  These values are extracted from the
 510        task Private_Data section of the Ada Task Control Block, and
 511        their interpretation depends on the target.  */
 512     ptid_t (*to_get_ada_task_ptid) (long lwp, long thread);
 513
 514     /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
 515        Return 0 if *READPTR is already at the end of the buffer.
 516        Return -1 if there is insufficient buffer for a whole entry.
 517        Return 1 if an entry was read into *TYPEP and *VALP.  */
 518     int (*to_auxv_parse) (struct target_ops *ops, gdb_byte **readptr,
 519                          gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 520
 521     /* Search SEARCH_SPACE_LEN bytes beginning at START_ADDR for the
 522        sequence of bytes in PATTERN with length PATTERN_LEN.
 523
 524        The result is 1 if found, 0 if not found, and -1 if there was an error
 525        requiring halting of the search (e.g. memory read error).
 526        If the pattern is found the address is recorded in FOUND_ADDRP.  */
 527     int (*to_search_memory) (struct target_ops *ops,
 528                              CORE_ADDR start_addr, ULONGEST search_space_len,
 529                              const gdb_byte *pattern, ULONGEST pattern_len,
 530                              CORE_ADDR *found_addrp);
 531
 532     /* Can target execute in reverse?  */
 533     int (*to_can_execute_reverse) (void);
 534
 535     /* Does this target support debugging multiple processes
 536        simultaneously?  */
 537     int (*to_supports_multi_process) (void);
 538
 539     int to_magic;
 540     /* Need sub-structure for target machine related rather than comm related?
 541      */
 542   };
 543
 544 /* Magic number for checking ops size.  If a struct doesn't end with this
 545    number, somebody changed the declaration but didn't change all the
 546    places that initialize one.  */
 547
 548 #define OPS_MAGIC       3840
 549
 550 /* The ops structure for our "current" target process.  This should
 551    never be NULL.  If there is no target, it points to the dummy_target.  */
 552
 553 extern struct target_ops current_target;
 554
 555 /* Define easy words for doing these operations on our current target.  */
 556
 557 #define target_shortname        (current_target.to_shortname)
 558 #define target_longname         (current_target.to_longname)
 559
 560 /* Does whatever cleanup is required for a target that we are no
 561    longer going to be calling.  QUITTING indicates that GDB is exiting
 562    and should not get hung on an error (otherwise it is important to
 563    perform clean termination, even if it takes a while).  This routine
 564    is automatically always called when popping the target off the
 565    target stack (to_beneath is undefined).  Closing file descriptors
 566    and freeing all memory allocated memory are typical things it
 567    should do.  */
 568
 569 void target_close (struct target_ops *targ, int quitting);
 570
 571 /* Attaches to a process on the target side.  Arguments are as passed
 572    to the `attach' command by the user.  This routine can be called
 573    when the target is not on the target-stack, if the target_can_run
 574    routine returns 1; in that case, it must push itself onto the stack.
 575    Upon exit, the target should be ready for normal operations, and
 576    should be ready to deliver the status of the process immediately
 577    (without waiting) to an upcoming target_wait call.  */
 578
 579 void target_attach (char *, int);
 580
 581 /* Some targets don't generate traps when attaching to the inferior,
 582    or their target_attach implementation takes care of the waiting.
 583    These targets must set to_attach_no_wait.  */
 584
 585 #define target_attach_no_wait \
 586      (current_target.to_attach_no_wait)
 587
 588 /* The target_attach operation places a process under debugger control,
 589    and stops the process.
 590
 591    This operation provides a target-specific hook that allows the
 592    necessary bookkeeping to be performed after an attach completes.  */
 593 #define target_post_attach(pid) \
 594      (*current_target.to_post_attach) (pid)
 595
 596 /* Takes a program previously attached to and detaches it.
 597    The program may resume execution (some targets do, some don't) and will
 598    no longer stop on signals, etc.  We better not have left any breakpoints
 599    in the program or it'll die when it hits one.  ARGS is arguments
 600    typed by the user (e.g. a signal to send the process).  FROM_TTY
 601    says whether to be verbose or not.  */
 602
 603 extern void target_detach (char *, int);
 604
 605 /* Disconnect from the current target without resuming it (leaving it
 606    waiting for a debugger).  */
 607
 608 extern void target_disconnect (char *, int);
 609
 610 /* Resume execution of the target process PTID.  STEP says whether to
 611    single-step or to run free; SIGGNAL is the signal to be given to
 612    the target, or TARGET_SIGNAL_0 for no signal.  The caller may not
 613    pass TARGET_SIGNAL_DEFAULT.  */
 614
 615 extern void target_resume (ptid_t ptid, int step, enum target_signal signal);
 616
 617 /* Wait for process pid to do something.  PTID = -1 to wait for any
 618    pid to do something.  Return pid of child, or -1 in case of error;
 619    store status through argument pointer STATUS.  Note that it is
 620    _NOT_ OK to throw_exception() out of target_wait() without popping
 621    the debugging target from the stack; GDB isn't prepared to get back
 622    to the prompt with a debugging target but without the frame cache,
 623    stop_pc, etc., set up.  */
 624
 625 extern ptid_t target_wait (ptid_t ptid, struct target_waitstatus *status);
 626
 627 /* Fetch at least register REGNO, or all regs if regno == -1.  No result.  */
 628
 629 extern void target_fetch_registers (struct regcache *regcache, int regno);
 630
 631 /* Store at least register REGNO, or all regs if REGNO == -1.
 632    It can store as many registers as it wants to, so target_prepare_to_store
 633    must have been previously called.  Calls error() if there are problems.  */
 634
 635 extern void target_store_registers (struct regcache *regcache, int regs);
 636
 637 /* Get ready to modify the registers array.  On machines which store
 638    individual registers, this doesn't need to do anything.  On machines
 639    which store all the registers in one fell swoop, this makes sure
 640    that REGISTERS contains all the registers from the program being
 641    debugged.  */
 642
 643 #define target_prepare_to_store(regcache)       \
 644      (*current_target.to_prepare_to_store) (regcache)
 645
 646 /* Returns true if this target can debug multiple processes
 647    simultaneously.  */
 648
 649 #define target_supports_multi_process() \
 650      (*current_target.to_supports_multi_process) ()
 651
 652 extern DCACHE *target_dcache;
 653
 654 extern int target_read_string (CORE_ADDR, char **, int, int *);
 655
 656 extern int target_read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len);
 657
 658 extern int target_write_memory (CORE_ADDR memaddr, const gdb_byte *myaddr,
 659                                 int len);
 660
 661 extern int xfer_memory (CORE_ADDR, gdb_byte *, int, int,
 662                         struct mem_attrib *, struct target_ops *);
 663
 664 /* Fetches the target's memory map.  If one is found it is sorted
 665    and returned, after some consistency checking.  Otherwise, NULL
 666    is returned.  */
 667 VEC(mem_region_s) *target_memory_map (void);
 668
 669 /* Erase the specified flash region.  */
 670 void target_flash_erase (ULONGEST address, LONGEST length);
 671
 672 /* Finish a sequence of flash operations.  */
 673 void target_flash_done (void);
 674
 675 /* Describes a request for a memory write operation.  */
 676 struct memory_write_request
 677   {
 678     /* Begining address that must be written. */
 679     ULONGEST begin;
 680     /* Past-the-end address. */
 681     ULONGEST end;
 682     /* The data to write. */
 683     gdb_byte *data;
 684     /* A callback baton for progress reporting for this request.  */
 685     void *baton;
 686   };
 687 typedef struct memory_write_request memory_write_request_s;
 688 DEF_VEC_O(memory_write_request_s);
 689
 690 /* Enumeration specifying different flash preservation behaviour.  */
 691 enum flash_preserve_mode
 692   {
 693     flash_preserve,
 694     flash_discard
 695   };
 696
 697 /* Write several memory blocks at once.  This version can be more
 698    efficient than making several calls to target_write_memory, in
 699    particular because it can optimize accesses to flash memory.
 700
 701    Moreover, this is currently the only memory access function in gdb
 702    that supports writing to flash memory, and it should be used for
 703    all cases where access to flash memory is desirable.
 704
 705    REQUESTS is the vector (see vec.h) of memory_write_request.
 706    PRESERVE_FLASH_P indicates what to do with blocks which must be
 707      erased, but not completely rewritten.
 708    PROGRESS_CB is a function that will be periodically called to provide
 709      feedback to user.  It will be called with the baton corresponding
 710      to the request currently being written.  It may also be called
 711      with a NULL baton, when preserved flash sectors are being rewritten.
 712
 713    The function returns 0 on success, and error otherwise.  */
 714 int target_write_memory_blocks (VEC(memory_write_request_s) *requests,
 715                                 enum flash_preserve_mode preserve_flash_p,
 716                                 void (*progress_cb) (ULONGEST, void *));
 717
 718 /* From infrun.c.  */
 719
 720 extern int inferior_has_forked (ptid_t pid, ptid_t *child_pid);
 721
 722 extern int inferior_has_vforked (ptid_t pid, ptid_t *child_pid);
 723
 724 extern int inferior_has_execd (ptid_t pid, char **execd_pathname);
 725
 726 /* From exec.c */
 727
 728 extern void print_section_info (struct target_ops *, bfd *);
 729
 730 /* Print a line about the current target.  */
 731
 732 #define target_files_info()     \
 733      (*current_target.to_files_info) (&current_target)
 734
 735 /* Insert a breakpoint at address BP_TGT->placed_address in the target
 736    machine.  Result is 0 for success, or an errno value.  */
 737
 738 #define target_insert_breakpoint(bp_tgt)        \
 739      (*current_target.to_insert_breakpoint) (bp_tgt)
 740
 741 /* Remove a breakpoint at address BP_TGT->placed_address in the target
 742    machine.  Result is 0 for success, or an errno value.  */
 743
 744 #define target_remove_breakpoint(bp_tgt)        \
 745      (*current_target.to_remove_breakpoint) (bp_tgt)
 746
 747 /* Initialize the terminal settings we record for the inferior,
 748    before we actually run the inferior.  */
 749
 750 #define target_terminal_init() \
 751      (*current_target.to_terminal_init) ()
 752
 753 /* Put the inferior's terminal settings into effect.
 754    This is preparation for starting or resuming the inferior.  */
 755
 756 #define target_terminal_inferior() \
 757      (*current_target.to_terminal_inferior) ()
 758
 759 /* Put some of our terminal settings into effect,
 760    enough to get proper results from our output,
 761    but do not change into or out of RAW mode
 762    so that no input is discarded.
 763
 764    After doing this, either terminal_ours or terminal_inferior
 765    should be called to get back to a normal state of affairs.  */
 766
 767 #define target_terminal_ours_for_output() \
 768      (*current_target.to_terminal_ours_for_output) ()
 769
 770 /* Put our terminal settings into effect.
 771    First record the inferior's terminal settings
 772    so they can be restored properly later.  */
 773
 774 #define target_terminal_ours() \
 775      (*current_target.to_terminal_ours) ()
 776
 777 /* Save our terminal settings.
 778    This is called from TUI after entering or leaving the curses
 779    mode.  Since curses modifies our terminal this call is here
 780    to take this change into account.  */
 781
 782 #define target_terminal_save_ours() \
 783      (*current_target.to_terminal_save_ours) ()
 784
 785 /* Print useful information about our terminal status, if such a thing
 786    exists.  */
 787
 788 #define target_terminal_info(arg, from_tty) \
 789      (*current_target.to_terminal_info) (arg, from_tty)
 790
 791 /* Kill the inferior process.   Make it go away.  */
 792
 793 extern void target_kill (void);
 794
 795 /* Load an executable file into the target process.  This is expected
 796    to not only bring new code into the target process, but also to
 797    update GDB's symbol tables to match.
 798
 799    ARG contains command-line arguments, to be broken down with
 800    buildargv ().  The first non-switch argument is the filename to
 801    load, FILE; the second is a number (as parsed by strtoul (..., ...,
 802    0)), which is an offset to apply to the load addresses of FILE's
 803    sections.  The target may define switches, or other non-switch
 804    arguments, as it pleases.  */
 805
 806 extern void target_load (char *arg, int from_tty);
 807
 808 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 809    name.  ADDRP is a CORE_ADDR * pointing to where the value of the
 810    symbol should be returned.  The result is 0 if successful, nonzero
 811    if the symbol does not exist in the target environment.  This
 812    function should not call error() if communication with the target
 813    is interrupted, since it is called from symbol reading, but should
 814    return nonzero, possibly doing a complain().  */
 815
 816 #define target_lookup_symbol(name, addrp) \
 817      (*current_target.to_lookup_symbol) (name, addrp)
 818
 819 /* Start an inferior process and set inferior_ptid to its pid.
 820    EXEC_FILE is the file to run.
 821    ALLARGS is a string containing the arguments to the program.
 822    ENV is the environment vector to pass.  Errors reported with error().
 823    On VxWorks and various standalone systems, we ignore exec_file.  */
 824
 825 void target_create_inferior (char *exec_file, char *args,
 826                              char **env, int from_tty);
 827
 828 /* Some targets (such as ttrace-based HPUX) don't allow us to request
 829    notification of inferior events such as fork and vork immediately
 830    after the inferior is created.  (This because of how gdb gets an
 831    inferior created via invoking a shell to do it.  In such a scenario,
 832    if the shell init file has commands in it, the shell will fork and
 833    exec for each of those commands, and we will see each such fork
 834    event.  Very bad.)
 835
 836    Such targets will supply an appropriate definition for this function.  */
 837
 838 #define target_post_startup_inferior(ptid) \
 839      (*current_target.to_post_startup_inferior) (ptid)
 840
 841 /* On some targets, the sequence of starting up an inferior requires
 842    some synchronization between gdb and the new inferior process, PID.  */
 843
 844 #define target_acknowledge_created_inferior(pid) \
 845      (*current_target.to_acknowledge_created_inferior) (pid)
 846
 847 /* On some targets, we can catch an inferior fork or vfork event when
 848    it occurs.  These functions insert/remove an already-created
 849    catchpoint for such events.  */
 850
 851 #define target_insert_fork_catchpoint(pid) \
 852      (*current_target.to_insert_fork_catchpoint) (pid)
 853
 854 #define target_remove_fork_catchpoint(pid) \
 855      (*current_target.to_remove_fork_catchpoint) (pid)
 856
 857 #define target_insert_vfork_catchpoint(pid) \
 858      (*current_target.to_insert_vfork_catchpoint) (pid)
 859
 860 #define target_remove_vfork_catchpoint(pid) \
 861      (*current_target.to_remove_vfork_catchpoint) (pid)
 862
 863 /* If the inferior forks or vforks, this function will be called at
 864    the next resume in order to perform any bookkeeping and fiddling
 865    necessary to continue debugging either the parent or child, as
 866    requested, and releasing the other.  Information about the fork
 867    or vfork event is available via get_last_target_status ().
 868    This function returns 1 if the inferior should not be resumed
 869    (i.e. there is another event pending).  */
 870
 871 int target_follow_fork (int follow_child);
 872
 873 /* On some targets, we can catch an inferior exec event when it
 874    occurs.  These functions insert/remove an already-created
 875    catchpoint for such events.  */
 876
 877 #define target_insert_exec_catchpoint(pid) \
 878      (*current_target.to_insert_exec_catchpoint) (pid)
 879
 880 #define target_remove_exec_catchpoint(pid) \
 881      (*current_target.to_remove_exec_catchpoint) (pid)
 882
 883 /* Returns TRUE if PID has exited.  And, also sets EXIT_STATUS to the
 884    exit code of PID, if any.  */
 885
 886 #define target_has_exited(pid,wait_status,exit_status) \
 887      (*current_target.to_has_exited) (pid,wait_status,exit_status)
 888
 889 /* The debugger has completed a blocking wait() call.  There is now
 890    some process event that must be processed.  This function should
 891    be defined by those targets that require the debugger to perform
 892    cleanup or internal state changes in response to the process event.  */
 893
 894 /* The inferior process has died.  Do what is right.  */
 895
 896 void target_mourn_inferior (void);
 897
 898 /* Does target have enough data to do a run or attach command? */
 899
 900 #define target_can_run(t) \
 901      ((t)->to_can_run) ()
 902
 903 /* post process changes to signal handling in the inferior.  */
 904
 905 #define target_notice_signals(ptid) \
 906      (*current_target.to_notice_signals) (ptid)
 907
 908 /* Check to see if a thread is still alive.  */
 909
 910 extern int target_thread_alive (ptid_t ptid);
 911
 912 /* Query for new threads and add them to the thread list.  */
 913
 914 extern void target_find_new_threads (void);
 915
 916 /* Make target stop in a continuable fashion.  (For instance, under
 917    Unix, this should act like SIGSTOP).  This function is normally
 918    used by GUIs to implement a stop button.  */
 919
 920 #define target_stop(ptid) (*current_target.to_stop) (ptid)
 921
 922 /* Send the specified COMMAND to the target's monitor
 923    (shell,interpreter) for execution.  The result of the query is
 924    placed in OUTBUF.  */
 925
 926 #define target_rcmd(command, outbuf) \
 927      (*current_target.to_rcmd) (command, outbuf)
 928
 929
 930 /* Does the target include all of memory, or only part of it?  This
 931    determines whether we look up the target chain for other parts of
 932    memory if this target can't satisfy a request.  */
 933
 934 #define target_has_all_memory   \
 935      (current_target.to_has_all_memory)
 936
 937 /* Does the target include memory?  (Dummy targets don't.)  */
 938
 939 #define target_has_memory       \
 940      (current_target.to_has_memory)
 941
 942 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 943    we start a process.)  */
 944
 945 #define target_has_stack        \
 946      (current_target.to_has_stack)
 947
 948 /* Does the target have registers?  (Exec files don't.)  */
 949
 950 #define target_has_registers    \
 951      (current_target.to_has_registers)
 952
 953 /* Does the target have execution?  Can we make it jump (through
 954    hoops), or pop its stack a few times?  This means that the current
 955    target is currently executing; for some targets, that's the same as
 956    whether or not the target is capable of execution, but there are
 957    also targets which can be current while not executing.  In that
 958    case this will become true after target_create_inferior or
 959    target_attach.  */
 960
 961 #define target_has_execution    \
 962      (current_target.to_has_execution)
 963
 964 /* Can the target support the debugger control of thread execution?
 965    Can it lock the thread scheduler?  */
 966
 967 #define target_can_lock_scheduler \
 968      (current_target.to_has_thread_control & tc_schedlock)
 969
 970 /* Should the target enable async mode if it is supported?  Temporary
 971    cludge until async mode is a strict superset of sync mode.  */
 972 extern int target_async_permitted;
 973
 974 /* Can the target support asynchronous execution? */
 975 #define target_can_async_p() (current_target.to_can_async_p ())
 976
 977 /* Is the target in asynchronous execution mode? */
 978 #define target_is_async_p() (current_target.to_is_async_p ())
 979
 980 int target_supports_non_stop (void);
 981
 982 /* Put the target in async mode with the specified callback function. */
 983 #define target_async(CALLBACK,CONTEXT) \
 984      (current_target.to_async ((CALLBACK), (CONTEXT)))
 985
 986 /* This is to be used ONLY within call_function_by_hand(). It provides
 987    a workaround, to have inferior function calls done in sychronous
 988    mode, even though the target is asynchronous. After
 989    target_async_mask(0) is called, calls to target_can_async_p() will
 990    return FALSE , so that target_resume() will not try to start the
 991    target asynchronously. After the inferior stops, we IMMEDIATELY
 992    restore the previous nature of the target, by calling
 993    target_async_mask(1). After that, target_can_async_p() will return
 994    TRUE. ANY OTHER USE OF THIS FEATURE IS DEPRECATED.
 995
 996    FIXME ezannoni 1999-12-13: we won't need this once we move
 997    the turning async on and off to the single execution commands,
 998    from where it is done currently, in remote_resume().  */
 999
1000 #define target_async_mask(MASK) \
1001   (current_target.to_async_mask (MASK))
1002
1003 /* Converts a process id to a string.  Usually, the string just contains
1004    `process xyz', but on some systems it may contain
1005    `process xyz thread abc'.  */
1006
1007 extern char *target_pid_to_str (ptid_t ptid);
1008
1009 extern char *normal_pid_to_str (ptid_t ptid);
1010
1011 /* Return a short string describing extra information about PID,
1012    e.g. "sleeping", "runnable", "running on LWP 3".  Null return value
1013    is okay.  */
1014
1015 #define target_extra_thread_info(TP) \
1016      (current_target.to_extra_thread_info (TP))
1017
1018 /* Attempts to find the pathname of the executable file
1019    that was run to create a specified process.
1020
1021    The process PID must be stopped when this operation is used.
1022
1023    If the executable file cannot be determined, NULL is returned.
1024
1025    Else, a pointer to a character string containing the pathname
1026    is returned.  This string should be copied into a buffer by
1027    the client if the string will not be immediately used, or if
1028    it must persist.  */
1029
1030 #define target_pid_to_exec_file(pid) \
1031      (current_target.to_pid_to_exec_file) (pid)
1032
1033 /*
1034  * Iterator function for target memory regions.
1035  * Calls a callback function once for each memory region 'mapped'
1036  * in the child process.  Defined as a simple macro rather than
1037  * as a function macro so that it can be tested for nullity.
1038  */
1039
1040 #define target_find_memory_regions(FUNC, DATA) \
1041      (current_target.to_find_memory_regions) (FUNC, DATA)
1042
1043 /*
1044  * Compose corefile .note section.
1045  */
1046
1047 #define target_make_corefile_notes(BFD, SIZE_P) \
1048      (current_target.to_make_corefile_notes) (BFD, SIZE_P)
1049
1050 /* Hardware watchpoint interfaces.  */
1051
1052 /* Returns non-zero if we were stopped by a hardware watchpoint (memory read or
1053    write).  */
1054
1055 #ifndef STOPPED_BY_WATCHPOINT
1056 #define STOPPED_BY_WATCHPOINT(w) \
1057    (*current_target.to_stopped_by_watchpoint) ()
1058 #endif
1059
1060 /* Non-zero if we have steppable watchpoints  */
1061
1062 #ifndef HAVE_STEPPABLE_WATCHPOINT
1063 #define HAVE_STEPPABLE_WATCHPOINT \
1064    (current_target.to_have_steppable_watchpoint)
1065 #endif
1066
1067 /* Non-zero if we have continuable watchpoints  */
1068
1069 #ifndef HAVE_CONTINUABLE_WATCHPOINT
1070 #define HAVE_CONTINUABLE_WATCHPOINT \
1071    (current_target.to_have_continuable_watchpoint)
1072 #endif
1073
1074 /* Provide defaults for hardware watchpoint functions.  */
1075
1076 /* If the *_hw_beakpoint functions have not been defined
1077    elsewhere use the definitions in the target vector.  */
1078
1079 /* Returns non-zero if we can set a hardware watchpoint of type TYPE.  TYPE is
1080    one of bp_hardware_watchpoint, bp_read_watchpoint, bp_write_watchpoint, or
1081    bp_hardware_breakpoint.  CNT is the number of such watchpoints used so far
1082    (including this one?).  OTHERTYPE is who knows what...  */
1083
1084 #ifndef TARGET_CAN_USE_HARDWARE_WATCHPOINT
1085 #define TARGET_CAN_USE_HARDWARE_WATCHPOINT(TYPE,CNT,OTHERTYPE) \
1086  (*current_target.to_can_use_hw_breakpoint) (TYPE, CNT, OTHERTYPE);
1087 #endif
1088
1089 #ifndef TARGET_REGION_OK_FOR_HW_WATCHPOINT
1090 #define TARGET_REGION_OK_FOR_HW_WATCHPOINT(addr, len) \
1091     (*current_target.to_region_ok_for_hw_watchpoint) (addr, len)
1092 #endif
1093
1094
1095 /* Set/clear a hardware watchpoint starting at ADDR, for LEN bytes.  TYPE is 0
1096    for write, 1 for read, and 2 for read/write accesses.  Returns 0 for
1097    success, non-zero for failure.  */
1098
1099 #ifndef target_insert_watchpoint
1100 #define target_insert_watchpoint(addr, len, type)       \
1101      (*current_target.to_insert_watchpoint) (addr, len, type)
1102
1103 #define target_remove_watchpoint(addr, len, type)       \
1104      (*current_target.to_remove_watchpoint) (addr, len, type)
1105 #endif
1106
1107 #ifndef target_insert_hw_breakpoint
1108 #define target_insert_hw_breakpoint(bp_tgt) \
1109      (*current_target.to_insert_hw_breakpoint) (bp_tgt)
1110
1111 #define target_remove_hw_breakpoint(bp_tgt) \
1112      (*current_target.to_remove_hw_breakpoint) (bp_tgt)
1113 #endif
1114
1115 #ifndef target_stopped_data_address
1116 #define target_stopped_data_address(target, x) \
1117     (*target.to_stopped_data_address) (target, x)
1118 #endif
1119
1120 #define target_watchpoint_addr_within_range(target, addr, start, length) \
1121   (*target.to_watchpoint_addr_within_range) (target, addr, start, length)
1122
1123 /* Target can execute in reverse?  */
1124 #define target_can_execute_reverse \
1125      (current_target.to_can_execute_reverse ? \
1126       current_target.to_can_execute_reverse () : 0)
1127
1128 extern const struct target_desc *target_read_description (struct target_ops *);
1129
1130 #define target_get_ada_task_ptid(lwp, tid) \
1131      (*current_target.to_get_ada_task_ptid) (lwp,tid)
1132
1133 /* Utility implementation of searching memory.  */
1134 extern int simple_search_memory (struct target_ops* ops,
1135                                  CORE_ADDR start_addr,
1136                                  ULONGEST search_space_len,
1137                                  const gdb_byte *pattern,
1138                                  ULONGEST pattern_len,
1139                                  CORE_ADDR *found_addrp);
1140
1141 /* Main entry point for searching memory.  */
1142 extern int target_search_memory (CORE_ADDR start_addr,
1143                                  ULONGEST search_space_len,
1144                                  const gdb_byte *pattern,
1145                                  ULONGEST pattern_len,
1146                                  CORE_ADDR *found_addrp);
1147
1148 /* Command logging facility.  */
1149
1150 #define target_log_command(p)                                           \
1151   do                                                                    \
1152     if (current_target.to_log_command)                                  \
1153       (*current_target.to_log_command) (p);                             \
1154   while (0)
1155
1156 /* Routines for maintenance of the target structures...
1157
1158    add_target:   Add a target to the list of all possible targets.
1159
1160    push_target:  Make this target the top of the stack of currently used
1161    targets, within its particular stratum of the stack.  Result
1162    is 0 if now atop the stack, nonzero if not on top (maybe
1163    should warn user).
1164
1165    unpush_target: Remove this from the stack of currently used targets,
1166    no matter where it is on the list.  Returns 0 if no
1167    change, 1 if removed from stack.
1168
1169    pop_target:   Remove the top thing on the stack of current targets.  */
1170
1171 extern void add_target (struct target_ops *);
1172
1173 extern int push_target (struct target_ops *);
1174
1175 extern int unpush_target (struct target_ops *);
1176
1177 extern void target_pre_inferior (int);
1178
1179 extern void target_preopen (int);
1180
1181 extern void pop_target (void);
1182
1183 /* Does whatever cleanup is required to get rid of all pushed targets.
1184    QUITTING is propagated to target_close; it indicates that GDB is
1185    exiting and should not get hung on an error (otherwise it is
1186    important to perform clean termination, even if it takes a
1187    while).  */
1188 extern void pop_all_targets (int quitting);
1189
1190 /* Like pop_all_targets, but pops only targets whose stratum is
1191    strictly above ABOVE_STRATUM.  */
1192 extern void pop_all_targets_above (enum strata above_stratum, int quitting);
1193
1194 extern CORE_ADDR target_translate_tls_address (struct objfile *objfile,
1195                                                CORE_ADDR offset);
1196
1197 /* Mark a pushed target as running or exited, for targets which do not
1198    automatically pop when not active.  */
1199
1200 void target_mark_running (struct target_ops *);
1201
1202 void target_mark_exited (struct target_ops *);
1203
1204 /* Struct section_table maps address ranges to file sections.  It is
1205    mostly used with BFD files, but can be used without (e.g. for handling
1206    raw disks, or files not in formats handled by BFD).  */
1207
1208 struct section_table
1209   {
1210     CORE_ADDR addr;             /* Lowest address in section */
1211     CORE_ADDR endaddr;          /* 1+highest address in section */
1212
1213     struct bfd_section *the_bfd_section;
1214
1215     bfd *bfd;                   /* BFD file pointer */
1216   };
1217
1218 /* Return the "section" containing the specified address.  */
1219 struct section_table *target_section_by_addr (struct target_ops *target,
1220                                               CORE_ADDR addr);
1221
1222
1223 /* From mem-break.c */
1224
1225 extern int memory_remove_breakpoint (struct bp_target_info *);
1226
1227 extern int memory_insert_breakpoint (struct bp_target_info *);
1228
1229 extern int default_memory_remove_breakpoint (struct gdbarch *, struct bp_target_info *);
1230
1231 extern int default_memory_insert_breakpoint (struct gdbarch *, struct bp_target_info *);
1232
1233
1234 /* From target.c */
1235
1236 extern void initialize_targets (void);
1237
1238 extern NORETURN void noprocess (void) ATTR_NORETURN;
1239
1240 extern void target_require_runnable (void);
1241
1242 extern void find_default_attach (struct target_ops *, char *, int);
1243
1244 extern void find_default_create_inferior (struct target_ops *,
1245                                           char *, char *, char **, int);
1246
1247 extern struct target_ops *find_run_target (void);
1248
1249 extern struct target_ops *find_core_target (void);
1250
1251 extern struct target_ops *find_target_beneath (struct target_ops *);
1252
1253 extern int target_resize_to_sections (struct target_ops *target,
1254                                       int num_added);
1255
1256 extern void remove_target_sections (bfd *abfd);
1257
1258 /* Read OS data object of type TYPE from the target, and return it in
1259    XML format.  The result is NUL-terminated and returned as a string,
1260    allocated using xmalloc.  If an error occurs or the transfer is
1261    unsupported, NULL is returned.  Empty objects are returned as
1262    allocated but empty strings.  */
1263
1264 extern char *target_get_osdata (const char *type);
1265
1266 \f
1267 /* Stuff that should be shared among the various remote targets.  */
1268
1269 /* Debugging level.  0 is off, and non-zero values mean to print some debug
1270    information (higher values, more information).  */
1271 extern int remote_debug;
1272
1273 /* Speed in bits per second, or -1 which means don't mess with the speed.  */
1274 extern int baud_rate;
1275 /* Timeout limit for response from target. */
1276 extern int remote_timeout;
1277
1278 \f
1279 /* Functions for helping to write a native target.  */
1280
1281 /* This is for native targets which use a unix/POSIX-style waitstatus.  */
1282 extern void store_waitstatus (struct target_waitstatus *, int);
1283
1284 /* These are in common/signals.c, but they're only used by gdb.  */
1285 extern enum target_signal default_target_signal_from_host (struct gdbarch *,
1286                                                            int);
1287 extern int default_target_signal_to_host (struct gdbarch *,
1288                                           enum target_signal);
1289
1290 /* Convert from a number used in a GDB command to an enum target_signal.  */
1291 extern enum target_signal target_signal_from_command (int);
1292 /* End of files in common/signals.c.  */
1293
1294 /* Set the show memory breakpoints mode to show, and installs a cleanup
1295    to restore it back to the current value.  */
1296 extern struct cleanup *make_show_memory_breakpoints_cleanup (int show);
1297
1298 \f
1299 /* Imported from machine dependent code */
1300
1301 /* Blank target vector entries are initialized to target_ignore. */
1302 void target_ignore (void);
1303
1304 extern struct target_ops deprecated_child_ops;
1305
1306 #endif /* !defined (TARGET_H) */