gdb/frame.h

   1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986, 1988-1994, 1996-2004, 2007-2012 Free Software
   4    Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #if !defined (FRAME_H)
  22 #define FRAME_H 1
  23
  24 /* The following is the intended naming schema for frame functions.
  25    It isn't 100% consistent, but it is aproaching that.  Frame naming
  26    schema:
  27
  28    Prefixes:
  29
  30    get_frame_WHAT...(): Get WHAT from the THIS frame (functionaly
  31    equivalent to THIS->next->unwind->what)
  32
  33    frame_unwind_WHAT...(): Unwind THIS frame's WHAT from the NEXT
  34    frame.
  35
  36    frame_unwind_caller_WHAT...(): Unwind WHAT for NEXT stack frame's
  37    real caller.  Any inlined functions in NEXT's stack frame are
  38    skipped.  Use these to ignore any potentially inlined functions,
  39    e.g. inlined into the first instruction of a library trampoline.
  40
  41    get_stack_frame_WHAT...(): Get WHAT for THIS frame, but if THIS is
  42    inlined, skip to the containing stack frame.
  43
  44    put_frame_WHAT...(): Put a value into this frame (unsafe, need to
  45    invalidate the frame / regcache afterwards) (better name more
  46    strongly hinting at its unsafeness)
  47
  48    safe_....(): Safer version of various functions, doesn't throw an
  49    error (leave this for later?).  Returns non-zero / non-NULL if the
  50    request succeeds, zero / NULL otherwize.
  51
  52    Suffixes:
  53
  54    void /frame/_WHAT(): Read WHAT's value into the buffer parameter.
  55
  56    ULONGEST /frame/_WHAT_unsigned(): Return an unsigned value (the
  57    alternative is *frame_unsigned_WHAT).
  58
  59    LONGEST /frame/_WHAT_signed(): Return WHAT signed value.
  60
  61    What:
  62
  63    /frame/_memory* (frame, coreaddr, len [, buf]): Extract/return
  64    *memory.
  65
  66    /frame/_register* (frame, regnum [, buf]): extract/return register.
  67
  68    CORE_ADDR /frame/_{pc,sp,...} (frame): Resume address, innner most
  69    stack *address, ...
  70
  71    */
  72
  73 struct symtab_and_line;
  74 struct frame_unwind;
  75 struct frame_base;
  76 struct block;
  77 struct gdbarch;
  78 struct ui_file;
  79
  80 /* The frame object.  */
  81
  82 struct frame_info;
  83
  84 /* The frame object's ID.  This provides a per-frame unique identifier
  85    that can be used to relocate a `struct frame_info' after a target
  86    resume or a frame cache destruct.  It of course assumes that the
  87    inferior hasn't unwound the stack past that frame.  */
  88
  89 struct frame_id
  90 {
  91   /* The frame's stack address.  This shall be constant through out
  92      the lifetime of a frame.  Note that this requirement applies to
  93      not just the function body, but also the prologue and (in theory
  94      at least) the epilogue.  Since that value needs to fall either on
  95      the boundary, or within the frame's address range, the frame's
  96      outer-most address (the inner-most address of the previous frame)
  97      is used.  Watch out for all the legacy targets that still use the
  98      function pointer register or stack pointer register.  They are
  99      wrong.
 100
 101      This field is valid only if stack_addr_p is true.  Otherwise, this
 102      frame represents the null frame.  */
 103   CORE_ADDR stack_addr;
 104
 105   /* The frame's code address.  This shall be constant through out the
 106      lifetime of the frame.  While the PC (a.k.a. resume address)
 107      changes as the function is executed, this code address cannot.
 108      Typically, it is set to the address of the entry point of the
 109      frame's function (as returned by get_frame_func).
 110
 111      For inlined functions (INLINE_DEPTH != 0), this is the address of
 112      the first executed instruction in the block corresponding to the
 113      inlined function.
 114
 115      This field is valid only if code_addr_p is true.  Otherwise, this
 116      frame is considered to have a wildcard code address, i.e. one that
 117      matches every address value in frame comparisons.  */
 118   CORE_ADDR code_addr;
 119
 120   /* The frame's special address.  This shall be constant through out the
 121      lifetime of the frame.  This is used for architectures that may have
 122      frames that do not change the stack but are still distinct and have
 123      some form of distinct identifier (e.g. the ia64 which uses a 2nd
 124      stack for registers).  This field is treated as unordered - i.e. will
 125      not be used in frame ordering comparisons.
 126
 127      This field is valid only if special_addr_p is true.  Otherwise, this
 128      frame is considered to have a wildcard special address, i.e. one that
 129      matches every address value in frame comparisons.  */
 130   CORE_ADDR special_addr;
 131
 132   /* Flags to indicate the above fields have valid contents.  */
 133   unsigned int stack_addr_p : 1;
 134   unsigned int code_addr_p : 1;
 135   unsigned int special_addr_p : 1;
 136
 137   /* It is non-zero for a frame made up by GDB without stack data
 138      representation in inferior, such as INLINE_FRAME or TAILCALL_FRAME.
 139      Caller of inlined function will have it zero, each more inner called frame
 140      will have it increasingly one, two etc.  Similarly for TAILCALL_FRAME.  */
 141   int artificial_depth;
 142 };
 143
 144 /* Methods for constructing and comparing Frame IDs.  */
 145
 146 /* For convenience.  All fields are zero.  This means "there is no frame".  */
 147 extern const struct frame_id null_frame_id;
 148
 149 /* This means "there is no frame ID, but there is a frame".  It should be
 150    replaced by best-effort frame IDs for the outermost frame, somehow.
 151    The implementation is only special_addr_p set.  */
 152 extern const struct frame_id outer_frame_id;
 153
 154 /* Flag to control debugging.  */
 155
 156 extern unsigned int frame_debug;
 157
 158 /* Construct a frame ID.  The first parameter is the frame's constant
 159    stack address (typically the outer-bound), and the second the
 160    frame's constant code address (typically the entry point).
 161    The special identifier address is set to indicate a wild card.  */
 162 extern struct frame_id frame_id_build (CORE_ADDR stack_addr,
 163                                        CORE_ADDR code_addr);
 164
 165 /* Construct a special frame ID.  The first parameter is the frame's constant
 166    stack address (typically the outer-bound), the second is the
 167    frame's constant code address (typically the entry point),
 168    and the third parameter is the frame's special identifier address.  */
 169 extern struct frame_id frame_id_build_special (CORE_ADDR stack_addr,
 170                                                CORE_ADDR code_addr,
 171                                                CORE_ADDR special_addr);
 172
 173 /* Construct a wild card frame ID.  The parameter is the frame's constant
 174    stack address (typically the outer-bound).  The code address as well
 175    as the special identifier address are set to indicate wild cards.  */
 176 extern struct frame_id frame_id_build_wild (CORE_ADDR stack_addr);
 177
 178 /* Returns non-zero when L is a valid frame (a valid frame has a
 179    non-zero .base).  The outermost frame is valid even without an
 180    ID.  */
 181 extern int frame_id_p (struct frame_id l);
 182
 183 /* Returns non-zero when L is a valid frame representing a frame made up by GDB
 184    without stack data representation in inferior, such as INLINE_FRAME or
 185    TAILCALL_FRAME.  */
 186 extern int frame_id_artificial_p (struct frame_id l);
 187
 188 /* Returns non-zero when L and R identify the same frame, or, if
 189    either L or R have a zero .func, then the same frame base.  */
 190 extern int frame_id_eq (struct frame_id l, struct frame_id r);
 191
 192 /* Write the internal representation of a frame ID on the specified
 193    stream.  */
 194 extern void fprint_frame_id (struct ui_file *file, struct frame_id id);
 195
 196
 197 /* Frame types.  Some are real, some are signal trampolines, and some
 198    are completely artificial (dummy).  */
 199
 200 enum frame_type
 201 {
 202   /* A true stack frame, created by the target program during normal
 203      execution.  */
 204   NORMAL_FRAME,
 205   /* A fake frame, created by GDB when performing an inferior function
 206      call.  */
 207   DUMMY_FRAME,
 208   /* A frame representing an inlined function, associated with an
 209      upcoming (prev, outer, older) NORMAL_FRAME.  */
 210   INLINE_FRAME,
 211   /* A virtual frame of a tail call - see dwarf2_tailcall_frame_unwind.  */
 212   TAILCALL_FRAME,
 213   /* In a signal handler, various OSs handle this in various ways.
 214      The main thing is that the frame may be far from normal.  */
 215   SIGTRAMP_FRAME,
 216   /* Fake frame representing a cross-architecture call.  */
 217   ARCH_FRAME,
 218   /* Sentinel or registers frame.  This frame obtains register values
 219      direct from the inferior's registers.  */
 220   SENTINEL_FRAME
 221 };
 222
 223 /* For every stopped thread, GDB tracks two frames: current and
 224    selected.  Current frame is the inner most frame of the selected
 225    thread.  Selected frame is the one being examined by the GDB
 226    CLI (selected using `up', `down', ...).  The frames are created
 227    on-demand (via get_prev_frame()) and then held in a frame cache.  */
 228 /* FIXME: cagney/2002-11-28: Er, there is a lie here.  If you do the
 229    sequence: `thread 1; up; thread 2; thread 1' you lose thread 1's
 230    selected frame.  At present GDB only tracks the selected frame of
 231    the current thread.  But be warned, that might change.  */
 232 /* FIXME: cagney/2002-11-14: At any time, only one thread's selected
 233    and current frame can be active.  Switching threads causes gdb to
 234    discard all that cached frame information.  Ulgh!  Instead, current
 235    and selected frame should be bound to a thread.  */
 236
 237 /* On demand, create the inner most frame using information found in
 238    the inferior.  If the inner most frame can't be created, throw an
 239    error.  */
 240 extern struct frame_info *get_current_frame (void);
 241
 242 /* Does the current target interface have enough state to be able to
 243    query the current inferior for frame info, and is the inferior in a
 244    state where that is possible?  */
 245 extern int has_stack_frames (void);
 246
 247 /* Invalidates the frame cache (this function should have been called
 248    invalidate_cached_frames).
 249
 250    FIXME: cagney/2002-11-28: There should be two methods: one that
 251    reverts the thread's selected frame back to current frame (for when
 252    the inferior resumes) and one that does not (for when the user
 253    modifies the target invalidating the frame cache).  */
 254 extern void reinit_frame_cache (void);
 255
 256 /* On demand, create the selected frame and then return it.  If the
 257    selected frame can not be created, this function prints then throws
 258    an error.  When MESSAGE is non-NULL, use it for the error message,
 259    otherwize use a generic error message.  */
 260 /* FIXME: cagney/2002-11-28: At present, when there is no selected
 261    frame, this function always returns the current (inner most) frame.
 262    It should instead, when a thread has previously had its frame
 263    selected (but not resumed) and the frame cache invalidated, find
 264    and then return that thread's previously selected frame.  */
 265 extern struct frame_info *get_selected_frame (const char *message);
 266
 267 /* If there is a selected frame, return it.  Otherwise, return NULL.  */
 268 extern struct frame_info *get_selected_frame_if_set (void);
 269
 270 /* Select a specific frame.  NULL, apparently implies re-select the
 271    inner most frame.  */
 272 extern void select_frame (struct frame_info *);
 273
 274 /* Given a FRAME, return the next (more inner, younger) or previous
 275    (more outer, older) frame.  */
 276 extern struct frame_info *get_prev_frame (struct frame_info *);
 277 extern struct frame_info *get_next_frame (struct frame_info *);
 278
 279 /* Given a frame's ID, relocate the frame.  Returns NULL if the frame
 280    is not found.  */
 281 extern struct frame_info *frame_find_by_id (struct frame_id id);
 282
 283 /* Base attributes of a frame: */
 284
 285 /* The frame's `resume' address.  Where the program will resume in
 286    this frame.
 287
 288    This replaced: frame->pc; */
 289 extern CORE_ADDR get_frame_pc (struct frame_info *);
 290
 291 /* Same as get_frame_pc, but return a boolean indication of whether
 292    the PC is actually available, instead of throwing an error.  */
 293
 294 extern int get_frame_pc_if_available (struct frame_info *frame,
 295                                       CORE_ADDR *pc);
 296
 297 /* An address (not necessarily aligned to an instruction boundary)
 298    that falls within THIS frame's code block.
 299
 300    When a function call is the last statement in a block, the return
 301    address for the call may land at the start of the next block.
 302    Similarly, if a no-return function call is the last statement in
 303    the function, the return address may end up pointing beyond the
 304    function, and possibly at the start of the next function.
 305
 306    These methods make an allowance for this.  For call frames, this
 307    function returns the frame's PC-1 which "should" be an address in
 308    the frame's block.  */
 309
 310 extern CORE_ADDR get_frame_address_in_block (struct frame_info *this_frame);
 311
 312 /* Same as get_frame_address_in_block, but returns a boolean
 313    indication of whether the frame address is determinable (when the
 314    PC is unavailable, it will not be), instead of possibly throwing an
 315    error trying to read an unavailable PC.  */
 316
 317 extern int
 318   get_frame_address_in_block_if_available (struct frame_info *this_frame,
 319                                            CORE_ADDR *pc);
 320
 321 /* The frame's inner-most bound.  AKA the stack-pointer.  Confusingly
 322    known as top-of-stack.  */
 323
 324 extern CORE_ADDR get_frame_sp (struct frame_info *);
 325
 326 /* Following on from the `resume' address.  Return the entry point
 327    address of the function containing that resume address, or zero if
 328    that function isn't known.  */
 329 extern CORE_ADDR get_frame_func (struct frame_info *fi);
 330
 331 /* Same as get_frame_func, but returns a boolean indication of whether
 332    the frame function is determinable (when the PC is unavailable, it
 333    will not be), instead of possibly throwing an error trying to read
 334    an unavailable PC.  */
 335
 336 extern int get_frame_func_if_available (struct frame_info *fi, CORE_ADDR *);
 337
 338 /* Closely related to the resume address, various symbol table
 339    attributes that are determined by the PC.  Note that for a normal
 340    frame, the PC refers to the resume address after the return, and
 341    not the call instruction.  In such a case, the address is adjusted
 342    so that it (approximately) identifies the call site (and not the
 343    return site).
 344
 345    NOTE: cagney/2002-11-28: The frame cache could be used to cache the
 346    computed value.  Working on the assumption that the bottle-neck is
 347    in the single step code, and that code causes the frame cache to be
 348    constantly flushed, caching things in a frame is probably of little
 349    benefit.  As they say `show us the numbers'.
 350
 351    NOTE: cagney/2002-11-28: Plenty more where this one came from:
 352    find_frame_block(), find_frame_partial_function(),
 353    find_frame_symtab(), find_frame_function().  Each will need to be
 354    carefully considered to determine if the real intent was for it to
 355    apply to the PC or the adjusted PC.  */
 356 extern void find_frame_sal (struct frame_info *frame,
 357                             struct symtab_and_line *sal);
 358
 359 /* Set the current source and line to the location given by frame
 360    FRAME, if possible.  When CENTER is true, adjust so the relevant
 361    line is in the center of the next 'list'.  */
 362
 363 void set_current_sal_from_frame (struct frame_info *, int);
 364
 365 /* Return the frame base (what ever that is) (DEPRECATED).
 366
 367    Old code was trying to use this single method for two conflicting
 368    purposes.  Such code needs to be updated to use either of:
 369
 370    get_frame_id: A low level frame unique identifier, that consists of
 371    both a stack and a function address, that can be used to uniquely
 372    identify a frame.  This value is determined by the frame's
 373    low-level unwinder, the stack part [typically] being the
 374    top-of-stack of the previous frame, and the function part being the
 375    function's start address.  Since the correct identification of a
 376    frameless function requires both a stack and function address,
 377    the old get_frame_base method was not sufficient.
 378
 379    get_frame_base_address: get_frame_locals_address:
 380    get_frame_args_address: A set of high-level debug-info dependant
 381    addresses that fall within the frame.  These addresses almost
 382    certainly will not match the stack address part of a frame ID (as
 383    returned by get_frame_base).
 384
 385    This replaced: frame->frame; */
 386
 387 extern CORE_ADDR get_frame_base (struct frame_info *);
 388
 389 /* Return the per-frame unique identifer.  Can be used to relocate a
 390    frame after a frame cache flush (and other similar operations).  If
 391    FI is NULL, return the null_frame_id.
 392
 393    NOTE: kettenis/20040508: These functions return a structure.  On
 394    platforms where structures are returned in static storage (vax,
 395    m68k), this may trigger compiler bugs in code like:
 396
 397    if (frame_id_eq (get_frame_id (l), get_frame_id (r)))
 398
 399    where the return value from the first get_frame_id (l) gets
 400    overwritten by the second get_frame_id (r).  Please avoid writing
 401    code like this.  Use code like:
 402
 403    struct frame_id id = get_frame_id (l);
 404    if (frame_id_eq (id, get_frame_id (r)))
 405
 406    instead, since that avoids the bug.  */
 407 extern struct frame_id get_frame_id (struct frame_info *fi);
 408 extern struct frame_id get_stack_frame_id (struct frame_info *fi);
 409 extern struct frame_id frame_unwind_caller_id (struct frame_info *next_frame);
 410
 411 /* Assuming that a frame is `normal', return its base-address, or 0 if
 412    the information isn't available.  NOTE: This address is really only
 413    meaningful to the frame's high-level debug info.  */
 414 extern CORE_ADDR get_frame_base_address (struct frame_info *);
 415
 416 /* Assuming that a frame is `normal', return the base-address of the
 417    local variables, or 0 if the information isn't available.  NOTE:
 418    This address is really only meaningful to the frame's high-level
 419    debug info.  Typically, the argument and locals share a single
 420    base-address.  */
 421 extern CORE_ADDR get_frame_locals_address (struct frame_info *);
 422
 423 /* Assuming that a frame is `normal', return the base-address of the
 424    parameter list, or 0 if that information isn't available.  NOTE:
 425    This address is really only meaningful to the frame's high-level
 426    debug info.  Typically, the argument and locals share a single
 427    base-address.  */
 428 extern CORE_ADDR get_frame_args_address (struct frame_info *);
 429
 430 /* The frame's level: 0 for innermost, 1 for its caller, ...; or -1
 431    for an invalid frame).  */
 432 extern int frame_relative_level (struct frame_info *fi);
 433
 434 /* Return the frame's type.  */
 435
 436 extern enum frame_type get_frame_type (struct frame_info *);
 437
 438 /* Return the frame's program space.  */
 439 extern struct program_space *get_frame_program_space (struct frame_info *);
 440
 441 /* Unwind THIS frame's program space from the NEXT frame.  */
 442 extern struct program_space *frame_unwind_program_space (struct frame_info *);
 443
 444 /* Return the frame's address space.  */
 445 extern struct address_space *get_frame_address_space (struct frame_info *);
 446
 447 /* For frames where we can not unwind further, describe why.  */
 448
 449 enum unwind_stop_reason
 450   {
 451 #define SET(name, description) name,
 452 #define FIRST_ENTRY(name) UNWIND_FIRST = name,
 453 #define LAST_ENTRY(name) UNWIND_LAST = name,
 454 #define FIRST_ERROR(name) UNWIND_FIRST_ERROR = name,
 455
 456 #include "unwind_stop_reasons.def"
 457 #undef SET
 458 #undef FIRST_ENTRY
 459 #undef LAST_ENTRY
 460 #undef FIRST_ERROR
 461   };
 462
 463 /* Return the reason why we can't unwind past this frame.  */
 464
 465 enum unwind_stop_reason get_frame_unwind_stop_reason (struct frame_info *);
 466
 467 /* Translate a reason code to an informative string.  */
 468
 469 const char *frame_stop_reason_string (enum unwind_stop_reason);
 470
 471 /* Unwind the stack frame so that the value of REGNUM, in the previous
 472    (up, older) frame is returned.  If VALUEP is NULL, don't
 473    fetch/compute the value.  Instead just return the location of the
 474    value.  */
 475 extern void frame_register_unwind (struct frame_info *frame, int regnum,
 476                                    int *optimizedp, int *unavailablep,
 477                                    enum lval_type *lvalp,
 478                                    CORE_ADDR *addrp, int *realnump,
 479                                    gdb_byte *valuep);
 480
 481 /* Fetch a register from this, or unwind a register from the next
 482    frame.  Note that the get_frame methods are wrappers to
 483    frame->next->unwind.  They all [potentially] throw an error if the
 484    fetch fails.  The value methods never return NULL, but usually
 485    do return a lazy value.  */
 486
 487 extern void frame_unwind_register (struct frame_info *frame,
 488                                    int regnum, gdb_byte *buf);
 489 extern void get_frame_register (struct frame_info *frame,
 490                                 int regnum, gdb_byte *buf);
 491
 492 struct value *frame_unwind_register_value (struct frame_info *frame,
 493                                            int regnum);
 494 struct value *get_frame_register_value (struct frame_info *frame,
 495                                         int regnum);
 496
 497 extern LONGEST frame_unwind_register_signed (struct frame_info *frame,
 498                                              int regnum);
 499 extern LONGEST get_frame_register_signed (struct frame_info *frame,
 500                                           int regnum);
 501 extern ULONGEST frame_unwind_register_unsigned (struct frame_info *frame,
 502                                                int regnum);
 503 extern ULONGEST get_frame_register_unsigned (struct frame_info *frame,
 504                                              int regnum);
 505
 506 /* Read a register from this, or unwind a register from the next
 507    frame.  Note that the read_frame methods are wrappers to
 508    get_frame_register_value, that do not throw if the result is
 509    optimized out or unavailable.  */
 510
 511 extern int read_frame_register_unsigned (struct frame_info *frame,
 512                                          int regnum, ULONGEST *val);
 513
 514 /* Get the value of the register that belongs to this FRAME.  This
 515    function is a wrapper to the call sequence ``frame_register_unwind
 516    (get_next_frame (FRAME))''.  As per frame_register_unwind(), if
 517    VALUEP is NULL, the registers value is not fetched/computed.  */
 518
 519 extern void frame_register (struct frame_info *frame, int regnum,
 520                             int *optimizedp, int *unavailablep,
 521                             enum lval_type *lvalp,
 522                             CORE_ADDR *addrp, int *realnump,
 523                             gdb_byte *valuep);
 524
 525 /* The reverse.  Store a register value relative to the specified
 526    frame.  Note: this call makes the frame's state undefined.  The
 527    register and frame caches must be flushed.  */
 528 extern void put_frame_register (struct frame_info *frame, int regnum,
 529                                 const gdb_byte *buf);
 530
 531 /* Read LEN bytes from one or multiple registers starting with REGNUM
 532    in frame FRAME, starting at OFFSET, into BUF.  If the register
 533    contents are optimized out or unavailable, set *OPTIMIZEDP,
 534    *UNAVAILABLEP accordingly.  */
 535 extern int get_frame_register_bytes (struct frame_info *frame, int regnum,
 536                                      CORE_ADDR offset, int len,
 537                                      gdb_byte *myaddr,
 538                                      int *optimizedp, int *unavailablep);
 539
 540 /* Write LEN bytes to one or multiple registers starting with REGNUM
 541    in frame FRAME, starting at OFFSET, into BUF.  */
 542 extern void put_frame_register_bytes (struct frame_info *frame, int regnum,
 543                                       CORE_ADDR offset, int len,
 544                                       const gdb_byte *myaddr);
 545
 546 /* Unwind the PC.  Strictly speaking return the resume address of the
 547    calling frame.  For GDB, `pc' is the resume address and not a
 548    specific register.  */
 549
 550 extern CORE_ADDR frame_unwind_caller_pc (struct frame_info *frame);
 551
 552 /* Same as frame_unwind_caller_pc, but returns a boolean indication of
 553    whether the caller PC is determinable (when the PC is unavailable,
 554    it will not be), instead of possibly throwing an error trying to
 555    read unavailable memory or registers.  */
 556
 557 extern int frame_unwind_caller_pc_if_available (struct frame_info *this_frame,
 558                                                 CORE_ADDR *pc);
 559
 560 /* Discard the specified frame.  Restoring the registers to the state
 561    of the caller.  */
 562 extern void frame_pop (struct frame_info *frame);
 563
 564 /* Return memory from the specified frame.  A frame knows its thread /
 565    LWP and hence can find its way down to a target.  The assumption
 566    here is that the current and previous frame share a common address
 567    space.
 568
 569    If the memory read fails, these methods throw an error.
 570
 571    NOTE: cagney/2003-06-03: Should there be unwind versions of these
 572    methods?  That isn't clear.  Can code, for instance, assume that
 573    this and the previous frame's memory or architecture are identical?
 574    If architecture / memory changes are always separated by special
 575    adaptor frames this should be ok.  */
 576
 577 extern void get_frame_memory (struct frame_info *this_frame, CORE_ADDR addr,
 578                               gdb_byte *buf, int len);
 579 extern LONGEST get_frame_memory_signed (struct frame_info *this_frame,
 580                                         CORE_ADDR memaddr, int len);
 581 extern ULONGEST get_frame_memory_unsigned (struct frame_info *this_frame,
 582                                            CORE_ADDR memaddr, int len);
 583
 584 /* Same as above, but return non-zero when the entire memory read
 585    succeeds, zero otherwize.  */
 586 extern int safe_frame_unwind_memory (struct frame_info *this_frame,
 587                                      CORE_ADDR addr, gdb_byte *buf, int len);
 588
 589 /* Return this frame's architecture.  */
 590 extern struct gdbarch *get_frame_arch (struct frame_info *this_frame);
 591
 592 /* Return the previous frame's architecture.  */
 593 extern struct gdbarch *frame_unwind_arch (struct frame_info *frame);
 594
 595 /* Return the previous frame's architecture, skipping inline functions.  */
 596 extern struct gdbarch *frame_unwind_caller_arch (struct frame_info *frame);
 597
 598
 599 /* Values for the source flag to be used in print_frame_info_base().  */
 600 enum print_what
 601   {
 602     /* Print only the source line, like in stepi.  */
 603     SRC_LINE = -1,
 604     /* Print only the location, i.e. level, address (sometimes)
 605        function, args, file, line, line num.  */
 606     LOCATION,
 607     /* Print both of the above.  */
 608     SRC_AND_LOC,
 609     /* Print location only, but always include the address.  */
 610     LOC_AND_ADDRESS
 611   };
 612
 613 /* Allocate zero initialized memory from the frame cache obstack.
 614    Appendices to the frame info (such as the unwind cache) should
 615    allocate memory using this method.  */
 616
 617 extern void *frame_obstack_zalloc (unsigned long size);
 618 #define FRAME_OBSTACK_ZALLOC(TYPE) \
 619   ((TYPE *) frame_obstack_zalloc (sizeof (TYPE)))
 620 #define FRAME_OBSTACK_CALLOC(NUMBER,TYPE) \
 621   ((TYPE *) frame_obstack_zalloc ((NUMBER) * sizeof (TYPE)))
 622
 623 /* Create a regcache, and copy the frame's registers into it.  */
 624 struct regcache *frame_save_as_regcache (struct frame_info *this_frame);
 625
 626 extern struct block *get_frame_block (struct frame_info *,
 627                                       CORE_ADDR *addr_in_block);
 628
 629 /* Return the `struct block' that belongs to the selected thread's
 630    selected frame.  If the inferior has no state, return NULL.
 631
 632    NOTE: cagney/2002-11-29:
 633
 634    No state?  Does the inferior have any execution state (a core file
 635    does, an executable does not).  At present the code tests
 636    `target_has_stack' but I'm left wondering if it should test
 637    `target_has_registers' or, even, a merged target_has_state.
 638
 639    Should it look at the most recently specified SAL?  If the target
 640    has no state, should this function try to extract a block from the
 641    most recently selected SAL?  That way `list foo' would give it some
 642    sort of reference point.  Then again, perhaps that would confuse
 643    things.
 644
 645    Calls to this function can be broken down into two categories: Code
 646    that uses the selected block as an additional, but optional, data
 647    point; Code that uses the selected block as a prop, when it should
 648    have the relevant frame/block/pc explicitly passed in.
 649
 650    The latter can be eliminated by correctly parameterizing the code,
 651    the former though is more interesting.  Per the "address" command,
 652    it occurs in the CLI code and makes it possible for commands to
 653    work, even when the inferior has no state.  */
 654
 655 extern struct block *get_selected_block (CORE_ADDR *addr_in_block);
 656
 657 extern struct symbol *get_frame_function (struct frame_info *);
 658
 659 extern CORE_ADDR get_pc_function_start (CORE_ADDR);
 660
 661 extern struct frame_info *find_relative_frame (struct frame_info *, int *);
 662
 663 extern void show_and_print_stack_frame (struct frame_info *fi, int print_level,
 664                                         enum print_what print_what);
 665
 666 extern void print_stack_frame (struct frame_info *, int print_level,
 667                                enum print_what print_what);
 668
 669 extern void print_frame_info (struct frame_info *, int print_level,
 670                               enum print_what print_what, int args);
 671
 672 extern struct frame_info *block_innermost_frame (const struct block *);
 673
 674 extern int deprecated_pc_in_call_dummy (struct gdbarch *gdbarch, CORE_ADDR pc);
 675
 676 extern int deprecated_frame_register_read (struct frame_info *frame, int regnum,
 677                                 gdb_byte *buf);
 678
 679 /* From stack.c.  */
 680
 681 extern const char print_entry_values_no[];
 682 extern const char print_entry_values_only[];
 683 extern const char print_entry_values_preferred[];
 684 extern const char print_entry_values_if_needed[];
 685 extern const char print_entry_values_both[];
 686 extern const char print_entry_values_compact[];
 687 extern const char print_entry_values_default[];
 688 extern const char *print_entry_values;
 689
 690 /* Inferior function parameter value read in from a frame.  */
 691
 692 struct frame_arg
 693 {
 694   /* Symbol for this parameter used for example for its name.  */
 695   struct symbol *sym;
 696
 697   /* Value of the parameter.  It is NULL if ERROR is not NULL; if both VAL and
 698      ERROR are NULL this parameter's value should not be printed.  */
 699   struct value *val;
 700
 701   /* String containing the error message, it is more usually NULL indicating no
 702      error occured reading this parameter.  */
 703   char *error;
 704
 705   /* One of the print_entry_values_* entries as appropriate specifically for
 706      this frame_arg.  It will be different from print_entry_values.  With
 707      print_entry_values_no this frame_arg should be printed as a normal
 708      parameter.  print_entry_values_only says it should be printed as entry
 709      value parameter.  print_entry_values_compact says it should be printed as
 710      both as a normal parameter and entry values parameter having the same
 711      value - print_entry_values_compact is not permitted fi ui_out_is_mi_like_p
 712      (in such case print_entry_values_no and print_entry_values_only is used
 713      for each parameter kind specifically.  */
 714   const char *entry_kind;
 715 };
 716
 717 extern void read_frame_arg (struct symbol *sym, struct frame_info *frame,
 718                             struct frame_arg *argp,
 719                             struct frame_arg *entryargp);
 720
 721 extern void args_info (char *, int);
 722
 723 extern void locals_info (char *, int);
 724
 725 extern void (*deprecated_selected_frame_level_changed_hook) (int);
 726
 727 extern void return_command (char *, int);
 728
 729 /* Set FRAME's unwinder temporarily, so that we can call a sniffer.
 730    Return a cleanup which should be called if unwinding fails, and
 731    discarded if it succeeds.  */
 732
 733 struct cleanup *frame_prepare_for_sniffer (struct frame_info *frame,
 734                                            const struct frame_unwind *unwind);
 735
 736 /* Notes (cagney/2002-11-27, drow/2003-09-06):
 737
 738    You might think that calls to this function can simply be replaced by a
 739    call to get_selected_frame().
 740
 741    Unfortunately, it isn't that easy.
 742
 743    The relevant code needs to be audited to determine if it is
 744    possible (or practical) to instead pass the applicable frame in as a
 745    parameter.  For instance, DEPRECATED_DO_REGISTERS_INFO() relied on
 746    the deprecated_selected_frame global, while its replacement,
 747    PRINT_REGISTERS_INFO(), is parameterized with the selected frame.
 748    The only real exceptions occur at the edge (in the CLI code) where
 749    user commands need to pick up the selected frame before proceeding.
 750
 751    There are also some functions called with a NULL frame meaning either "the
 752    program is not running" or "use the selected frame".
 753
 754    This is important.  GDB is trying to stamp out the hack:
 755
 756    saved_frame = deprecated_safe_get_selected_frame ();
 757    select_frame (...);
 758    hack_using_global_selected_frame ();
 759    select_frame (saved_frame);
 760
 761    Take care!
 762
 763    This function calls get_selected_frame if the inferior should have a
 764    frame, or returns NULL otherwise.  */
 765
 766 extern struct frame_info *deprecated_safe_get_selected_frame (void);
 767
 768 /* Create a frame using the specified BASE and PC.  */
 769
 770 extern struct frame_info *create_new_frame (CORE_ADDR base, CORE_ADDR pc);
 771
 772 /* Return true if the frame unwinder for frame FI is UNWINDER; false
 773    otherwise.  */
 774
 775 extern int frame_unwinder_is (struct frame_info *fi,
 776                               const struct frame_unwind *unwinder);
 777
 778 #endif /* !defined (FRAME_H)  */