gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997,
   4    1998, 1999, 2000, 2001, 2002, 2003, 2004, 2007, 2008, 2009, 2010, 2011
   5    Free Software Foundation, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #if !defined (FRAME_H)
  23 #define FRAME_H 1
  24
  25 /* The following is the intended naming schema for frame functions.
  26    It isn't 100% consistent, but it is aproaching that.  Frame naming
  27    schema:
  28
  29    Prefixes:
  30
  31    get_frame_WHAT...(): Get WHAT from the THIS frame (functionaly
  32    equivalent to THIS->next->unwind->what)
  33
  34    frame_unwind_WHAT...(): Unwind THIS frame's WHAT from the NEXT
  35    frame.
  36
  37    frame_unwind_caller_WHAT...(): Unwind WHAT for NEXT stack frame's
  38    real caller.  Any inlined functions in NEXT's stack frame are
  39    skipped.  Use these to ignore any potentially inlined functions,
  40    e.g. inlined into the first instruction of a library trampoline.
  41
  42    get_stack_frame_WHAT...(): Get WHAT for THIS frame, but if THIS is
  43    inlined, skip to the containing stack frame.
  44
  45    put_frame_WHAT...(): Put a value into this frame (unsafe, need to
  46    invalidate the frame / regcache afterwards) (better name more
  47    strongly hinting at its unsafeness)
  48
  49    safe_....(): Safer version of various functions, doesn't throw an
  50    error (leave this for later?).  Returns non-zero / non-NULL if the
  51    request succeeds, zero / NULL otherwize.
  52
  53    Suffixes:
  54
  55    void /frame/_WHAT(): Read WHAT's value into the buffer parameter.
  56
  57    ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the
  58    alternative is *frame_unsigned_WHAT).
  59
  60    LONGEST /frame/_WHAT_signed(): Return WHAT signed value.
  61
  62    What:
  63
  64    /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return
  65    *memory.
  66
  67    /frame/_register* (frame, regnum [, buf]): extract/return register.
  68
  69    CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most
  70    stack *address, ...
  71
  72    */
  73
  74 struct symtab_and_line;
  75 struct frame_unwind;
  76 struct frame_base;
  77 struct block;
  78 struct gdbarch;
  79 struct ui_file;
  80
  81 /* The frame object.  */
  82
  83 struct frame_info;
  84
  85 /* The frame object's ID.  This provides a per-frame unique identifier
  86    that can be used to relocate a `struct frame_info' after a target
  87    resume or a frame cache destruct.  It of course assumes that the
  88    inferior hasn't unwound the stack past that frame.  */
  89
  90 struct frame_id
  91 {
  92   /* The frame's stack address.  This shall be constant through out
  93      the lifetime of a frame.  Note that this requirement applies to
  94      not just the function body, but also the prologue and (in theory
  95      at least) the epilogue.  Since that value needs to fall either on
  96      the boundary, or within the frame's address range, the frame's
  97      outer-most address (the inner-most address of the previous frame)
  98      is used.  Watch out for all the legacy targets that still use the
  99      function pointer register or stack pointer register.  They are
 100      wrong.
 101
 102      This field is valid only if stack_addr_p is true.  Otherwise, this
 103      frame represents the null frame.  */
 104   CORE_ADDR stack_addr;
 105
 106   /* The frame's code address.  This shall be constant through out the
 107      lifetime of the frame.  While the PC (a.k.a. resume address)
 108      changes as the function is executed, this code address cannot.
 109      Typically, it is set to the address of the entry point of the
 110      frame's function (as returned by get_frame_func).
 111
 112      For inlined functions (INLINE_DEPTH != 0), this is the address of
 113      the first executed instruction in the block corresponding to the
 114      inlined function.
 115
 116      This field is valid only if code_addr_p is true.  Otherwise, this
 117      frame is considered to have a wildcard code address, i.e. one that
 118      matches every address value in frame comparisons.  */
 119   CORE_ADDR code_addr;
 120
 121   /* The frame's special address.  This shall be constant through out the
 122      lifetime of the frame.  This is used for architectures that may have
 123      frames that do not change the stack but are still distinct and have
 124      some form of distinct identifier (e.g. the ia64 which uses a 2nd
 125      stack for registers).  This field is treated as unordered - i.e. will
 126      not be used in frame ordering comparisons.
 127
 128      This field is valid only if special_addr_p is true.  Otherwise, this
 129      frame is considered to have a wildcard special address, i.e. one that
 130      matches every address value in frame comparisons.  */
 131   CORE_ADDR special_addr;
 132
 133   /* Flags to indicate the above fields have valid contents.  */
 134   unsigned int stack_addr_p : 1;
 135   unsigned int code_addr_p : 1;
 136   unsigned int special_addr_p : 1;
 137
 138   /* The inline depth of this frame.  A frame representing a "called"
 139      inlined function will have this set to a nonzero value.  */
 140   int inline_depth;
 141 };
 142
 143 /* Methods for constructing and comparing Frame IDs.  */
 144
 145 /* For convenience.  All fields are zero.  This means "there is no frame".  */
 146 extern const struct frame_id null_frame_id;
 147
 148 /* This means "there is no frame ID, but there is a frame".  It should be
 149    replaced by best-effort frame IDs for the outermost frame, somehow.
 150    The implementation is only special_addr_p set.  */
 151 extern const struct frame_id outer_frame_id;
 152
 153 /* Flag to control debugging.  */
 154
 155 extern int frame_debug;
 156
 157 /* Construct a frame ID.  The first parameter is the frame's constant
 158    stack address (typically the outer-bound), and the second the
 159    frame's constant code address (typically the entry point).
 160    The special identifier address is set to indicate a wild card.  */
 161 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
 162                                        CORE_ADDR code_addr);
 163
 164 /* Construct a special frame ID.  The first parameter is the frame's constant
 165    stack address (typically the outer-bound), the second is the
 166    frame's constant code address (typically the entry point),
 167    and the third parameter is the frame's special identifier address.  */
 168 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
 169                                                CORE_ADDR code_addr,
 170                                                CORE_ADDR special_addr);
 171
 172 /* Construct a wild card frame ID.  The parameter is the frame's constant
 173    stack address (typically the outer-bound).  The code address as well
 174    as the special identifier address are set to indicate wild cards.  */
 175 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
 176
 177 /* Returns non-zero when L is a valid frame (a valid frame has a
 178    non-zero .base).  The outermost frame is valid even without an
 179    ID.  */
 180 extern int frame_id_p (struct frame_id l);
 181
 182 /* Returns non-zero when L is a valid frame representing an inlined
 183    function.  */
 184 extern int frame_id_inlined_p (struct frame_id l);
 185
 186 /* Returns non-zero when L and R identify the same frame, or, if
 187    either L or R have a zero .func, then the same frame base.  */
 188 extern int frame_id_eq (struct frame_id l, struct frame_id r);
 189
 190 /* Write the internal representation of a frame ID on the specified
 191    stream.  */
 192 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
 193
 194
 195 /* Frame types.  Some are real, some are signal trampolines, and some
 196    are completely artificial (dummy).  */
 197
 198 enum frame_type
 199 {
 200   /* A true stack frame, created by the target program during normal
 201      execution.  */
 202   NORMAL_FRAME,
 203   /* A fake frame, created by GDB when performing an inferior function
 204      call.  */
 205   DUMMY_FRAME,
 206   /* A frame representing an inlined function, associated with an
 207      upcoming (prev, outer, older) NORMAL_FRAME.  */
 208   INLINE_FRAME,
 209   /* In a signal handler, various OSs handle this in various ways.
 210      The main thing is that the frame may be far from normal.  */
 211   SIGTRAMP_FRAME,
 212   /* Fake frame representing a cross-architecture call.  */
 213   ARCH_FRAME,
 214   /* Sentinel or registers frame.  This frame obtains register values
 215      direct from the inferior's registers.  */
 216   SENTINEL_FRAME
 217 };
 218
 219 /* For every stopped thread, GDB tracks two frames: current and
 220    selected.  Current frame is the inner most frame of the selected
 221    thread.  Selected frame is the one being examined by the GDB
 222    CLI (selected using `up', `down', ...).  The frames are created
 223    on-demand (via get_prev_frame()) and then held in a frame cache.  */
 224 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
 225    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
 226    selected frame.  At present GDB only tracks the selected frame of
 227    the current thread.  But be warned, that might change.  */
 228 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
 229    and current frame can be active.  Switching threads causes gdb to
 230    discard all that cached frame information.  Ulgh!  Instead, current
 231    and selected frame should be bound to a thread.  */
 232
 233 /* On demand, create the inner most frame using information found in
 234    the inferior.  If the inner most frame can't be created, throw an
 235    error.  */
 236 extern struct frame_info *get_current_frame (void);
 237
 238 /* Does the current target interface have enough state to be able to
 239    query the current inferior for frame info, and is the inferior in a
 240    state where that is possible?  */
 241 extern int has_stack_frames (void);
 242
 243 /* Invalidates the frame cache (this function should have been called
 244    invalidate_cached_frames).
 245
 246    FIXME: cagney/2002-11-28: There should be two methods: one that
 247    reverts the thread's selected frame back to current frame (for when
 248    the inferior resumes) and one that does not (for when the user
 249    modifies the target invalidating the frame cache).  */
 250 extern void reinit_frame_cache (void);
 251
 252 /* On demand, create the selected frame and then return it.  If the
 253    selected frame can not be created, this function prints then throws
 254    an error.  When MESSAGE is non-NULL, use it for the error message,
 255    otherwize use a generic error message.  */
 256 /* FIXME: cagney/2002-11-28: At present, when there is no selected
 257    frame, this function always returns the current (inner most) frame.
 258    It should instead, when a thread has previously had its frame
 259    selected (but not resumed) and the frame cache invalidated, find
 260    and then return that thread's previously selected frame.  */
 261 extern struct frame_info *get_selected_frame (const char *message);
 262
 263 /* If there is a selected frame, return it.  Otherwise, return NULL.  */
 264 extern struct frame_info *get_selected_frame_if_set (void);
 265
 266 /* Select a specific frame.  NULL, apparently implies re-select the
 267    inner most frame.  */
 268 extern void select_frame (struct frame_info *);
 269
 270 /* Given a FRAME, return the next (more inner, younger) or previous
 271    (more outer, older) frame.  */
 272 extern struct frame_info *get_prev_frame (struct frame_info *);
 273 extern struct frame_info *get_next_frame (struct frame_info *);
 274
 275 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
 276    is not found.  */
 277 extern struct frame_info *frame_find_by_id (struct frame_id id);
 278
 279 /* Base attributes of a frame: */
 280
 281 /* The frame's `resume' address.  Where the program will resume in
 282    this frame.
 283
 284    This replaced: frame->pc; */
 285 extern CORE_ADDR get_frame_pc (struct frame_info *);
 286
 287 /* An address (not necessarily aligned to an instruction boundary)
 288    that falls within THIS frame's code block.
 289
 290    When a function call is the last statement in a block, the return
 291    address for the call may land at the start of the next block.
 292    Similarly, if a no-return function call is the last statement in
 293    the function, the return address may end up pointing beyond the
 294    function, and possibly at the start of the next function.
 295
 296    These methods make an allowance for this.  For call frames, this
 297    function returns the frame's PC-1 which "should" be an address in
 298    the frame's block.  */
 299
 300 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
 301
 302 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
 303    known as top-of-stack.  */
 304
 305 extern CORE_ADDR get_frame_sp (struct frame_info *);
 306
 307 /* Following on from the `resume' address.  Return the entry point
 308    address of the function containing that resume address, or zero if
 309    that function isn't known.  */
 310 extern CORE_ADDR get_frame_func (struct frame_info *fi);
 311
 312 /* Closely related to the resume address, various symbol table
 313    attributes that are determined by the PC.  Note that for a normal
 314    frame, the PC refers to the resume address after the return, and
 315    not the call instruction.  In such a case, the address is adjusted
 316    so that it (approximately) identifies the call site (and not the
 317    return site).
 318
 319    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
 320    computed value.  Working on the assumption that the bottle-neck is
 321    in the single step code, and that code causes the frame cache to be
 322    constantly flushed, caching things in a frame is probably of little
 323    benefit.  As they say `show us the numbers'.
 324
 325    NOTE: cagney/2002-11-28: Plenty more where this one came from:
 326    find_frame_block(), find_frame_partial_function(),
 327    find_frame_symtab(), find_frame_function().  Each will need to be
 328    carefully considered to determine if the real intent was for it to
 329    apply to the PC or the adjusted PC.  */
 330 extern void find_frame_sal (struct frame_info *frame,
 331                             struct symtab_and_line *sal);
 332
 333 /* Set the current source and line to the location given by frame
 334    FRAME, if possible.  When CENTER is true, adjust so the relevant
 335    line is in the center of the next 'list'.  */
 336
 337 void set_current_sal_from_frame (struct frame_info *, int);
 338
 339 /* Return the frame base (what ever that is) (DEPRECATED).
 340
 341    Old code was trying to use this single method for two conflicting
 342    purposes.  Such code needs to be updated to use either of:
 343
 344    get_frame_id: A low level frame unique identifier, that consists of
 345    both a stack and a function address, that can be used to uniquely
 346    identify a frame.  This value is determined by the frame's
 347    low-level unwinder, the stack part [typically] being the
 348    top-of-stack of the previous frame, and the function part being the
 349    function's start address.  Since the correct identification of a
 350    frameless function requires both a stack and function address,
 351    the old get_frame_base method was not sufficient.
 352
 353    get_frame_base_address: get_frame_locals_address:
 354    get_frame_args_address: A set of high-level debug-info dependant
 355    addresses that fall within the frame.  These addresses almost
 356    certainly will not match the stack address part of a frame ID (as
 357    returned by get_frame_base).
 358
 359    This replaced: frame->frame; */
 360
 361 extern CORE_ADDR get_frame_base (struct frame_info *);
 362
 363 /* Return the per-frame unique identifer.  Can be used to relocate a
 364    frame after a frame cache flush (and other similar operations).  If
 365    FI is NULL, return the null_frame_id.
 366
 367    NOTE: kettenis/20040508: These functions return a structure.  On
 368    platforms where structures are returned in static storage (vax,
 369    m68k), this may trigger compiler bugs in code like:
 370
 371    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
 372
 373    where the return value from the first get_frame_id (l) gets
 374    overwritten by the second get_frame_id (r).  Please avoid writing
 375    code like this.  Use code like:
 376
 377    struct frame_id id = get_frame_id (l);
 378    if (frame_id_eq (id, get_frame_id (r)))
 379
 380    instead, since that avoids the bug.  */
 381 extern struct frame_id get_frame_id (struct frame_info *fi);
 382 extern struct frame_id get_stack_frame_id (struct frame_info *fi);
 383 extern struct frame_id frame_unwind_caller_id (struct frame_info *next_frame);
 384
 385 /* Assuming that a frame is `normal', return its base-address, or 0 if
 386    the information isn't available.  NOTE: This address is really only
 387    meaningful to the frame's high-level debug info.  */
 388 extern CORE_ADDR get_frame_base_address (struct frame_info *);
 389
 390 /* Assuming that a frame is `normal', return the base-address of the
 391    local variables, or 0 if the information isn't available.  NOTE:
 392    This address is really only meaningful to the frame's high-level
 393    debug info.  Typically, the argument and locals share a single
 394    base-address.  */
 395 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
 396
 397 /* Assuming that a frame is `normal', return the base-address of the
 398    parameter list, or 0 if that information isn't available.  NOTE:
 399    This address is really only meaningful to the frame's high-level
 400    debug info.  Typically, the argument and locals share a single
 401    base-address.  */
 402 extern CORE_ADDR get_frame_args_address (struct frame_info *);
 403
 404 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
 405    for an invalid frame).  */
 406 extern int frame_relative_level (struct frame_info *fi);
 407
 408 /* Return the frame's type.  */
 409
 410 extern enum frame_type get_frame_type (struct frame_info *);
 411
 412 /* Return the frame's program space.  */
 413 extern struct program_space *get_frame_program_space (struct frame_info *);
 414
 415 /* Unwind THIS frame's program space from the NEXT frame.  */
 416 extern struct program_space *frame_unwind_program_space (struct frame_info *);
 417
 418 /* Return the frame's address space.  */
 419 extern struct address_space *get_frame_address_space (struct frame_info *);
 420
 421 /* For frames where we can not unwind further, describe why.  */
 422
 423 enum unwind_stop_reason
 424   {
 425     /* No particular reason; either we haven't tried unwinding yet,
 426        or we didn't fail.  */
 427     UNWIND_NO_REASON,
 428
 429     /* The previous frame's analyzer returns an invalid result
 430        from this_id.
 431
 432        FIXME drow/2006-08-16: This is how GDB used to indicate end of
 433        stack.  We should migrate to a model where frames always have a
 434        valid ID, and this becomes not just an error but an internal
 435        error.  But that's a project for another day.  */
 436     UNWIND_NULL_ID,
 437
 438     /* All the conditions after this point are considered errors;
 439        abnormal stack termination.  If a backtrace stops for one
 440        of these reasons, we'll let the user know.  This marker
 441        is not a valid stop reason.  */
 442     UNWIND_FIRST_ERROR,
 443
 444     /* This frame ID looks like it ought to belong to a NEXT frame,
 445        but we got it for a PREV frame.  Normally, this is a sign of
 446        unwinder failure.  It could also indicate stack corruption.  */
 447     UNWIND_INNER_ID,
 448
 449     /* This frame has the same ID as the previous one.  That means
 450        that unwinding further would almost certainly give us another
 451        frame with exactly the same ID, so break the chain.  Normally,
 452        this is a sign of unwinder failure.  It could also indicate
 453        stack corruption.  */
 454     UNWIND_SAME_ID,
 455
 456     /* The frame unwinder didn't find any saved PC, but we needed
 457        one to unwind further.  */
 458     UNWIND_NO_SAVED_PC,
 459   };
 460
 461 /* Return the reason why we can't unwind past this frame.  */
 462
 463 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
 464
 465 /* Translate a reason code to an informative string.  */
 466
 467 const char *frame_stop_reason_string (enum unwind_stop_reason);
 468
 469 /* Unwind the stack frame so that the value of REGNUM, in the previous
 470    (up, older) frame is returned.  If VALUEP is NULL, don't
 471    fetch/compute the value.  Instead just return the location of the
 472    value.  */
 473 extern void frame_register_unwind (struct frame_info *frame, int regnum,
 474                                    int *optimizedp, int *unavailablep,
 475                                    enum lval_type *lvalp,
 476                                    CORE_ADDR *addrp, int *realnump,
 477                                    gdb_byte *valuep);
 478
 479 /* Fetch a register from this, or unwind a register from the next
 480    frame.  Note that the get_frame methods are wrappers to
 481    frame->next->unwind.  They all [potentially] throw an error if the
 482    fetch fails.  The value methods never return NULL, but usually
 483    do return a lazy value.  */
 484
 485 extern void frame_unwind_register (struct frame_info *frame,
 486                                    int regnum, gdb_byte *buf);
 487 extern void get_frame_register (struct frame_info *frame,
 488                                 int regnum, gdb_byte *buf);
 489
 490 struct value *frame_unwind_register_value (struct frame_info *frame,
 491                                            int regnum);
 492 struct value *get_frame_register_value (struct frame_info *frame,
 493                                         int regnum);
 494
 495 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
 496                                              int regnum);
 497 extern LONGEST get_frame_register_signed (struct frame_info *frame,
 498                                           int regnum);
 499 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
 500                                                int regnum);
 501 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
 502                                              int regnum);
 503
 504
 505 /* Get the value of the register that belongs to this FRAME.  This
 506    function is a wrapper to the call sequence ``frame_register_unwind
 507    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
 508    VALUEP is NULL, the registers value is not fetched/computed.  */
 509
 510 extern void frame_register (struct frame_info *frame, int regnum,
 511                             int *optimizedp, int *unavailablep,
 512                             enum lval_type *lvalp,
 513                             CORE_ADDR *addrp, int *realnump,
 514                             gdb_byte *valuep);
 515
 516 /* The reverse.  Store a register value relative to the specified
 517    frame.  Note: this call makes the frame's state undefined.  The
 518    register and frame caches must be flushed.  */
 519 extern void put_frame_register (struct frame_info *frame, int regnum,
 520                                 const gdb_byte *buf);
 521
 522 /* Read LEN bytes from one or multiple registers starting with REGNUM
 523    in frame FRAME, starting at OFFSET, into BUF.  If the register
 524    contents are optimized out or unavailable, set *OPTIMIZEDP,
 525    *UNAVAILABLEP accordingly.  */
 526 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
 527                                      CORE_ADDR offset, int len,
 528                                      gdb_byte *myaddr,
 529                                      int *optimizedp, int *unavailablep);
 530
 531 /* Write LEN bytes to one or multiple registers starting with REGNUM
 532    in frame FRAME, starting at OFFSET, into BUF.  */
 533 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
 534                                       CORE_ADDR offset, int len,
 535                                       const gdb_byte *myaddr);
 536
 537 /* Unwind the PC.  Strictly speaking return the resume address of the
 538    calling frame.  For GDB, `pc' is the resume address and not a
 539    specific register.  */
 540
 541 extern CORE_ADDR frame_unwind_caller_pc (struct frame_info *frame);
 542
 543 /* Discard the specified frame.  Restoring the registers to the state
 544    of the caller.  */
 545 extern void frame_pop (struct frame_info *frame);
 546
 547 /* Return memory from the specified frame.  A frame knows its thread /
 548    LWP and hence can find its way down to a target.  The assumption
 549    here is that the current and previous frame share a common address
 550    space.
 551
 552    If the memory read fails, these methods throw an error.
 553
 554    NOTE: cagney/2003-06-03: Should there be unwind versions of these
 555    methods?  That isn't clear.  Can code, for instance, assume that
 556    this and the previous frame's memory or architecture are identical?
 557    If architecture / memory changes are always separated by special
 558    adaptor frames this should be ok.  */
 559
 560 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
 561                               gdb_byte *buf, int len);
 562 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
 563                                         CORE_ADDR memaddr, int len);
 564 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
 565                                            CORE_ADDR memaddr, int len);
 566
 567 /* Same as above, but return non-zero when the entire memory read
 568    succeeds, zero otherwize.  */
 569 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
 570                                      CORE_ADDR addr, gdb_byte *buf, int len);
 571
 572 /* Return this frame's architecture.  */
 573 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
 574
 575 /* Return the previous frame's architecture.  */
 576 extern struct gdbarch *frame_unwind_arch (struct frame_info *frame);
 577
 578 /* Return the previous frame's architecture, skipping inline functions.  */
 579 extern struct gdbarch *frame_unwind_caller_arch (struct frame_info *frame);
 580
 581
 582 /* Values for the source flag to be used in print_frame_info_base().  */
 583 enum print_what
 584   {
 585     /* Print only the source line, like in stepi.  */
 586     SRC_LINE = -1,
 587     /* Print only the location, i.e. level, address (sometimes)
 588        function, args, file, line, line num.  */
 589     LOCATION,
 590     /* Print both of the above.  */
 591     SRC_AND_LOC,
 592     /* Print location only, but always include the address.  */
 593     LOC_AND_ADDRESS
 594   };
 595
 596 /* Allocate zero initialized memory from the frame cache obstack.
 597    Appendices to the frame info (such as the unwind cache) should
 598    allocate memory using this method.  */
 599
 600 extern void *frame_obstack_zalloc (unsigned long size);
 601 #define FRAME_OBSTACK_ZALLOC(TYPE) \
 602   ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
 603 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) \
 604   ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
 605
 606 /* Create a regcache, and copy the frame's registers into it.  */
 607 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
 608
 609 extern struct block *get_frame_block (struct frame_info *,
 610                                       CORE_ADDR *addr_in_block);
 611
 612 /* Return the `struct block' that belongs to the selected thread's
 613    selected frame.  If the inferior has no state, return NULL.
 614
 615    NOTE: cagney/2002-11-29:
 616
 617    No state?  Does the inferior have any execution state (a core file
 618    does, an executable does not).  At present the code tests
 619    `target_has_stack' but I'm left wondering if it should test
 620    `target_has_registers' or, even, a merged target_has_state.
 621
 622    Should it look at the most recently specified SAL?  If the target
 623    has no state, should this function try to extract a block from the
 624    most recently selected SAL?  That way `list foo' would give it some
 625    sort of reference point.  Then again, perhaps that would confuse
 626    things.
 627
 628    Calls to this function can be broken down into two categories: Code
 629    that uses the selected block as an additional, but optional, data
 630    point; Code that uses the selected block as a prop, when it should
 631    have the relevant frame/block/pc explicitly passed in.
 632
 633    The latter can be eliminated by correctly parameterizing the code,
 634    the former though is more interesting.  Per the "address" command,
 635    it occurs in the CLI code and makes it possible for commands to
 636    work, even when the inferior has no state.  */
 637
 638 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 639
 640 extern struct symbol *get_frame_function (struct frame_info *);
 641
 642 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 643
 644 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 645
 646 extern void show_and_print_stack_frame (struct frame_info *fi, int print_level,
 647                                         enum print_what print_what);
 648
 649 extern void print_stack_frame (struct frame_info *, int print_level,
 650                                enum print_what print_what);
 651
 652 extern void print_frame_info (struct frame_info *, int print_level,
 653                               enum print_what print_what, int args);
 654
 655 extern struct frame_info *block_innermost_frame (struct block *);
 656
 657 extern int deprecated_pc_in_call_dummy (struct gdbarch *gdbarch, CORE_ADDR pc);
 658
 659 /* FIXME: cagney/2003-02-02: Should be deprecated or replaced with a
 660    function called get_frame_register_p().  This slightly weird (and
 661    older) variant of get_frame_register() returns zero (indicating the
 662    register value is unavailable/invalid) if either: the register
 663    isn't cached; or the register has been optimized out; or the
 664    register contents are unavailable (because they haven't been
 665    collected in a traceframe).  Problem is, neither check is exactly
 666    correct.  A register can't be optimized out (it may not have been
 667    saved as part of a function call); The fact that a register isn't
 668    in the register cache doesn't mean that the register isn't
 669    available (it could have been fetched from memory).  */
 670
 671 extern int frame_register_read (struct frame_info *frame, int regnum,
 672                                 gdb_byte *buf);
 673
 674 /* From stack.c.  */
 675 extern void args_info (char *, int);
 676
 677 extern void locals_info (char *, int);
 678
 679 extern void (*deprecated_selected_frame_level_changed_hook) (int);
 680
 681 extern void return_command (char *, int);
 682
 683 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
 684    Return a cleanup which should be called if unwinding fails, and
 685    discarded if it succeeds.  */
 686
 687 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
 688                                            const struct frame_unwind *unwind);
 689
 690 /* Notes (cagney/2002-11-27, drow/2003-09-06):
 691
 692    You might think that calls to this function can simply be replaced by a
 693    call to get_selected_frame().
 694
 695    Unfortunately, it isn't that easy.
 696
 697    The relevant code needs to be audited to determine if it is
 698    possible (or practical) to instead pass the applicable frame in as a
 699    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
 700    the deprecated_selected_frame global, while its replacement,
 701    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
 702    The only real exceptions occur at the edge (in the CLI code) where
 703    user commands need to pick up the selected frame before proceeding.
 704
 705    There are also some functions called with a NULL frame meaning either "the
 706    program is not running" or "use the selected frame".
 707
 708    This is important.  GDB is trying to stamp out the hack:
 709
 710    saved_frame = deprecated_safe_get_selected_frame ();
 711    select_frame (...);
 712    hack_using_global_selected_frame ();
 713    select_frame (saved_frame);
 714
 715    Take care!
 716
 717    This function calls get_selected_frame if the inferior should have a
 718    frame, or returns NULL otherwise.  */
 719
 720 extern struct frame_info *deprecated_safe_get_selected_frame (void);
 721
 722 /* Create a frame using the specified BASE and PC.  */
 723
 724 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 725
 726 /* Return true if the frame unwinder for frame FI is UNWINDER; false
 727    otherwise.  */
 728
 729 extern int frame_unwinder_is (struct frame_info *fi,
 730                               const struct frame_unwind *unwinder);
 731
 732 #endif /* !defined (FRAME_H)  */