| 1 | /* Representation of stack frame debug information |
| 2 | * Copyright (C) 1996,1997, 2000 Free Software Foundation |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2, or (at your option) |
| 7 | * any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this software; see the file COPYING. If not, write to |
| 16 | * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, |
| 17 | * Boston, MA 02111-1307 USA |
| 18 | * |
| 19 | * As a special exception, the Free Software Foundation gives permission |
| 20 | * for additional uses of the text contained in its release of GUILE. |
| 21 | * |
| 22 | * The exception is that, if you link the GUILE library with other files |
| 23 | * to produce an executable, this does not by itself cause the |
| 24 | * resulting executable to be covered by the GNU General Public License. |
| 25 | * Your use of that executable is in no way restricted on account of |
| 26 | * linking the GUILE library code into it. |
| 27 | * |
| 28 | * This exception does not however invalidate any other reasons why |
| 29 | * the executable file might be covered by the GNU General Public License. |
| 30 | * |
| 31 | * This exception applies only to the code released by the |
| 32 | * Free Software Foundation under the name GUILE. If you copy |
| 33 | * code from other Free Software Foundation releases into a copy of |
| 34 | * GUILE, as the General Public License permits, the exception does |
| 35 | * not apply to the code that you add in this way. To avoid misleading |
| 36 | * anyone as to the status of such modified files, you must delete |
| 37 | * this exception notice from them. |
| 38 | * |
| 39 | * If you write modifications of your own for GUILE, it is your choice |
| 40 | * whether to permit this exception to apply to your modifications. |
| 41 | * If you do not wish that, delete this exception notice. |
| 42 | * |
| 43 | * The author can be reached at djurfeldt@nada.kth.se |
| 44 | * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */ |
| 45 | |
| 46 | /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999, |
| 47 | gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */ |
| 48 | |
| 49 | \f |
| 50 | |
| 51 | #include "libguile/_scm.h" |
| 52 | #include "libguile/eval.h" |
| 53 | #include "libguile/debug.h" |
| 54 | #include "libguile/continuations.h" |
| 55 | #include "libguile/struct.h" |
| 56 | #include "libguile/macros.h" |
| 57 | #include "libguile/procprop.h" |
| 58 | #include "libguile/modules.h" |
| 59 | #include "libguile/root.h" |
| 60 | #include "libguile/strings.h" |
| 61 | |
| 62 | #include "libguile/validate.h" |
| 63 | #include "libguile/stacks.h" |
| 64 | |
| 65 | \f |
| 66 | /* {Frames and stacks} |
| 67 | * |
| 68 | * The debugging evaluator creates debug frames on the stack. These |
| 69 | * are linked from the innermost frame and outwards. The last frame |
| 70 | * created can always be accessed as SCM_LAST_DEBUG_FRAME. |
| 71 | * Continuations contain a pointer to the innermost debug frame on the |
| 72 | * continuation stack. |
| 73 | * |
| 74 | * Each debug frame contains a set of flags and information about one |
| 75 | * or more stack frames. The case of multiple frames occurs due to |
| 76 | * tail recursion. The maximal number of stack frames which can be |
| 77 | * recorded in one debug frame can be set dynamically with the debug |
| 78 | * option FRAMES. |
| 79 | * |
| 80 | * Stack frame information is of two types: eval information (the |
| 81 | * expression being evaluated and its environment) and apply |
| 82 | * information (the procedure being applied and its arguments). A |
| 83 | * stack frame normally corresponds to an eval/apply pair, but macros |
| 84 | * and special forms (which are implemented as macros in Guile) only |
| 85 | * have eval information and apply calls leads to apply only frames. |
| 86 | * |
| 87 | * Since we want to record the total stack information and later |
| 88 | * manipulate this data at the scheme level in the debugger, we need |
| 89 | * to transform it into a new representation. In the following code |
| 90 | * section you'll find the functions implementing this data type. |
| 91 | * |
| 92 | * Representation: |
| 93 | * |
| 94 | * The stack is represented as a struct with an id slot and a tail |
| 95 | * array of scm_info_frame structs. |
| 96 | * |
| 97 | * A frame is represented as a pair where the car contains a stack and |
| 98 | * the cdr an inum. The inum is an index to the first SCM value of |
| 99 | * the scm_info_frame struct. |
| 100 | * |
| 101 | * Stacks |
| 102 | * Constructor |
| 103 | * make-stack |
| 104 | * Selectors |
| 105 | * stack-id |
| 106 | * stack-ref |
| 107 | * Inspector |
| 108 | * stack-length |
| 109 | * |
| 110 | * Frames |
| 111 | * Constructor |
| 112 | * last-stack-frame |
| 113 | * Selectors |
| 114 | * frame-number |
| 115 | * frame-source |
| 116 | * frame-procedure |
| 117 | * frame-arguments |
| 118 | * frame-previous |
| 119 | * frame-next |
| 120 | * Predicates |
| 121 | * frame-real? |
| 122 | * frame-procedure? |
| 123 | * frame-evaluating-args? |
| 124 | * frame-overflow? */ |
| 125 | |
| 126 | \f |
| 127 | |
| 128 | /* Some auxiliary functions for reading debug frames off the stack. |
| 129 | */ |
| 130 | |
| 131 | /* Stacks often contain pointers to other items on the stack; for |
| 132 | example, each scm_debug_frame structure contains a pointer to the |
| 133 | next frame out. When we capture a continuation, we copy the stack |
| 134 | into the heap, and just leave all the pointers unchanged. This |
| 135 | makes it simple to restore the continuation --- just copy the stack |
| 136 | back! However, if we retrieve a pointer from the heap copy to |
| 137 | another item that was originally on the stack, we have to add an |
| 138 | offset to the pointer to discover the new referent. |
| 139 | |
| 140 | If PTR is a pointer retrieved from a continuation, whose original |
| 141 | target was on the stack, and OFFSET is the appropriate offset from |
| 142 | the original stack to the continuation, then RELOC_MUMBLE (PTR, |
| 143 | OFFSET) is a pointer to the copy in the continuation of the |
| 144 | original referent, cast to an scm_debug_MUMBLE *. */ |
| 145 | #define RELOC_INFO(ptr, offset) \ |
| 146 | ((scm_debug_info *) ((SCM_STACKITEM *) (ptr) + (offset))) |
| 147 | #define RELOC_FRAME(ptr, offset) \ |
| 148 | ((scm_debug_frame *) ((SCM_STACKITEM *) (ptr) + (offset))) |
| 149 | |
| 150 | |
| 151 | /* Count number of debug info frames on a stack, beginning with |
| 152 | * DFRAME. OFFSET is used for relocation of pointers when the stack |
| 153 | * is read from a continuation. |
| 154 | */ |
| 155 | static int |
| 156 | stack_depth (scm_debug_frame *dframe,long offset,SCM *id,int *maxp) |
| 157 | { |
| 158 | int n; |
| 159 | int max_depth = SCM_BACKTRACE_MAXDEPTH; |
| 160 | for (n = 0; |
| 161 | dframe && !SCM_VOIDFRAMEP (*dframe) && n < max_depth; |
| 162 | dframe = RELOC_FRAME (dframe->prev, offset)) |
| 163 | { |
| 164 | if (SCM_EVALFRAMEP (*dframe)) |
| 165 | { |
| 166 | scm_debug_info * info = RELOC_INFO (dframe->info, offset); |
| 167 | n += (info - dframe->vect) / 2 + 1; |
| 168 | /* Data in the apply part of an eval info frame comes from previous |
| 169 | stack frame if the scm_debug_info vector is overflowed. */ |
| 170 | if ((((info - dframe->vect) & 1) == 0) |
| 171 | && SCM_OVERFLOWP (*dframe) |
| 172 | && !SCM_UNBNDP (info[1].a.proc)) |
| 173 | ++n; |
| 174 | } |
| 175 | else |
| 176 | ++n; |
| 177 | } |
| 178 | if (dframe && SCM_VOIDFRAMEP (*dframe)) |
| 179 | *id = dframe->vect[0].id; |
| 180 | else if (dframe) |
| 181 | *maxp = 1; |
| 182 | return n; |
| 183 | } |
| 184 | |
| 185 | /* Read debug info from DFRAME into IFRAME. |
| 186 | */ |
| 187 | static void |
| 188 | read_frame (scm_debug_frame *dframe,long offset,scm_info_frame *iframe) |
| 189 | { |
| 190 | scm_bits_t flags = SCM_UNPACK (SCM_INUM0); /* UGh. */ |
| 191 | if (SCM_EVALFRAMEP (*dframe)) |
| 192 | { |
| 193 | scm_debug_info * info = RELOC_INFO (dframe->info, offset); |
| 194 | if ((info - dframe->vect) & 1) |
| 195 | { |
| 196 | /* Debug.vect ends with apply info. */ |
| 197 | --info; |
| 198 | if (!SCM_UNBNDP (info[1].a.proc)) |
| 199 | { |
| 200 | flags |= SCM_FRAMEF_PROC; |
| 201 | iframe->proc = info[1].a.proc; |
| 202 | iframe->args = info[1].a.args; |
| 203 | if (!SCM_ARGS_READY_P (*dframe)) |
| 204 | flags |= SCM_FRAMEF_EVAL_ARGS; |
| 205 | } |
| 206 | } |
| 207 | iframe->source = scm_make_memoized (info[0].e.exp, info[0].e.env); |
| 208 | } |
| 209 | else |
| 210 | { |
| 211 | flags |= SCM_FRAMEF_PROC; |
| 212 | iframe->proc = dframe->vect[0].a.proc; |
| 213 | iframe->args = dframe->vect[0].a.args; |
| 214 | } |
| 215 | iframe->flags = flags; |
| 216 | } |
| 217 | |
| 218 | /* Look up the first body form of the apply closure. We'll use this |
| 219 | below to prevent it from being displayed. |
| 220 | */ |
| 221 | static SCM |
| 222 | get_applybody () |
| 223 | { |
| 224 | SCM cell = scm_sym2vcell (scm_sym_apply, SCM_BOOL_F, SCM_BOOL_F); |
| 225 | if (SCM_CONSP (cell) && SCM_CLOSUREP (SCM_CDR (cell))) |
| 226 | return SCM_CADR (SCM_CODE (SCM_CDR (cell))); |
| 227 | else |
| 228 | return SCM_UNDEFINED; |
| 229 | } |
| 230 | |
| 231 | #define NEXT_FRAME(iframe, n, quit) \ |
| 232 | do { \ |
| 233 | if (SCM_NIMP (iframe->source) \ |
| 234 | && SCM_EQ_P (SCM_MEMOIZED_EXP (iframe->source), applybody)) \ |
| 235 | { \ |
| 236 | iframe->source = SCM_BOOL_F; \ |
| 237 | if (SCM_FALSEP (iframe->proc)) \ |
| 238 | { \ |
| 239 | --iframe; \ |
| 240 | ++n; \ |
| 241 | } \ |
| 242 | } \ |
| 243 | ++iframe; \ |
| 244 | if (--n == 0) \ |
| 245 | goto quit; \ |
| 246 | } while (0) |
| 247 | |
| 248 | |
| 249 | /* Fill the scm_info_frame vector IFRAME with data from N stack frames |
| 250 | * starting with the first stack frame represented by debug frame |
| 251 | * DFRAME. |
| 252 | */ |
| 253 | |
| 254 | static int |
| 255 | read_frames (scm_debug_frame *dframe,long offset,int n,scm_info_frame *iframes) |
| 256 | { |
| 257 | scm_info_frame *iframe = iframes; |
| 258 | scm_debug_info *info; |
| 259 | static SCM applybody = SCM_UNDEFINED; |
| 260 | |
| 261 | /* The value of applybody has to be setup after r4rs.scm has executed. */ |
| 262 | if (SCM_UNBNDP (applybody)) |
| 263 | applybody = get_applybody (); |
| 264 | for (; |
| 265 | dframe && !SCM_VOIDFRAMEP (*dframe) && n > 0; |
| 266 | dframe = RELOC_FRAME (dframe->prev, offset)) |
| 267 | { |
| 268 | read_frame (dframe, offset, iframe); |
| 269 | if (SCM_EVALFRAMEP (*dframe)) |
| 270 | { |
| 271 | /* If current frame is a macro during expansion, we should |
| 272 | skip the previously recorded macro transformer |
| 273 | application frame. */ |
| 274 | if (SCM_MACROEXPP (*dframe) && iframe > iframes) |
| 275 | { |
| 276 | *(iframe - 1) = *iframe; |
| 277 | --iframe; |
| 278 | } |
| 279 | info = RELOC_INFO (dframe->info, offset); |
| 280 | if ((info - dframe->vect) & 1) |
| 281 | --info; |
| 282 | /* Data in the apply part of an eval info frame comes from |
| 283 | previous stack frame if the scm_debug_info vector is overflowed. */ |
| 284 | else if (SCM_OVERFLOWP (*dframe) |
| 285 | && !SCM_UNBNDP (info[1].a.proc)) |
| 286 | { |
| 287 | NEXT_FRAME (iframe, n, quit); |
| 288 | iframe->flags = SCM_UNPACK(SCM_INUM0) | SCM_FRAMEF_PROC; |
| 289 | iframe->proc = info[1].a.proc; |
| 290 | iframe->args = info[1].a.args; |
| 291 | } |
| 292 | if (SCM_OVERFLOWP (*dframe)) |
| 293 | iframe->flags |= SCM_FRAMEF_OVERFLOW; |
| 294 | info -= 2; |
| 295 | NEXT_FRAME (iframe, n, quit); |
| 296 | while (info >= dframe->vect) |
| 297 | { |
| 298 | if (!SCM_UNBNDP (info[1].a.proc)) |
| 299 | { |
| 300 | iframe->flags = SCM_UNPACK(SCM_INUM0) | SCM_FRAMEF_PROC; |
| 301 | iframe->proc = info[1].a.proc; |
| 302 | iframe->args = info[1].a.args; |
| 303 | } |
| 304 | else |
| 305 | iframe->flags = SCM_UNPACK (SCM_INUM0); |
| 306 | iframe->source = scm_make_memoized (info[0].e.exp, |
| 307 | info[0].e.env); |
| 308 | info -= 2; |
| 309 | NEXT_FRAME (iframe, n, quit); |
| 310 | } |
| 311 | } |
| 312 | else if (SCM_EQ_P (iframe->proc, scm_f_gsubr_apply)) |
| 313 | /* Skip gsubr apply frames. */ |
| 314 | continue; |
| 315 | else |
| 316 | { |
| 317 | NEXT_FRAME (iframe, n, quit); |
| 318 | } |
| 319 | quit: |
| 320 | if (iframe > iframes) |
| 321 | (iframe - 1) -> flags |= SCM_FRAMEF_REAL; |
| 322 | } |
| 323 | return iframe - iframes; /* Number of frames actually read */ |
| 324 | } |
| 325 | |
| 326 | /* Narrow STACK by cutting away stackframes (mutatingly). |
| 327 | * |
| 328 | * Inner frames (most recent) are cut by advancing the frames pointer. |
| 329 | * Outer frames are cut by decreasing the recorded length. |
| 330 | * |
| 331 | * Cut maximally INNER inner frames and OUTER outer frames using |
| 332 | * the keys INNER_KEY and OUTER_KEY. |
| 333 | * |
| 334 | * Frames are cut away starting at the end points and moving towards |
| 335 | * the center of the stack. The key is normally compared to the |
| 336 | * operator in application frames. Frames up to and including the key |
| 337 | * are cut. |
| 338 | * |
| 339 | * If INNER_KEY is #t a different scheme is used for inner frames: |
| 340 | * |
| 341 | * Frames up to but excluding the first source frame originating from |
| 342 | * a user module are cut, except for possible application frames |
| 343 | * between the user frame and the last system frame previously |
| 344 | * encountered. |
| 345 | */ |
| 346 | |
| 347 | static void |
| 348 | narrow_stack (SCM stack,int inner,SCM inner_key,int outer,SCM outer_key) |
| 349 | { |
| 350 | scm_stack *s = SCM_STACK (stack); |
| 351 | int i; |
| 352 | int n = s->length; |
| 353 | |
| 354 | /* Cut inner part. */ |
| 355 | if (SCM_EQ_P (inner_key, SCM_BOOL_T)) |
| 356 | /* Cut all frames up to user module code */ |
| 357 | { |
| 358 | for (i = 0; inner; ++i, --inner) |
| 359 | { |
| 360 | SCM m = s->frames[i].source; |
| 361 | if ( SCM_MEMOIZEDP (m) |
| 362 | && SCM_NIMP (SCM_MEMOIZED_ENV (m)) |
| 363 | && SCM_FALSEP (scm_system_module_env_p (SCM_MEMOIZED_ENV (m)))) |
| 364 | { |
| 365 | /* Back up in order to include any non-source frames */ |
| 366 | while (i > 0 |
| 367 | && !((m = s->frames[i - 1].source, SCM_MEMOIZEDP (m)) |
| 368 | || (SCM_NIMP (m = s->frames[i - 1].proc) |
| 369 | && SCM_NFALSEP (scm_procedure_p (m)) |
| 370 | && SCM_NFALSEP (scm_procedure_property |
| 371 | (m, scm_sym_system_procedure))))) |
| 372 | { |
| 373 | --i; |
| 374 | ++inner; |
| 375 | } |
| 376 | break; |
| 377 | } |
| 378 | } |
| 379 | } |
| 380 | else |
| 381 | /* Use standard cutting procedure. */ |
| 382 | { |
| 383 | for (i = 0; inner; --inner) |
| 384 | if (SCM_EQ_P (s->frames[i++].proc, inner_key)) |
| 385 | break; |
| 386 | } |
| 387 | s->frames = &s->frames[i]; |
| 388 | n -= i; |
| 389 | |
| 390 | /* Cut outer part. */ |
| 391 | for (; n && outer; --outer) |
| 392 | if (SCM_EQ_P (s->frames[--n].proc, outer_key)) |
| 393 | break; |
| 394 | |
| 395 | s->length = n; |
| 396 | } |
| 397 | |
| 398 | \f |
| 399 | |
| 400 | /* Stacks |
| 401 | */ |
| 402 | |
| 403 | SCM scm_stack_type; |
| 404 | |
| 405 | SCM_DEFINE (scm_stack_p, "stack?", 1, 0, 0, |
| 406 | (SCM obj), |
| 407 | "Return @code{#t} if @var{obj} is a calling stack.") |
| 408 | #define FUNC_NAME s_scm_stack_p |
| 409 | { |
| 410 | return SCM_BOOL(SCM_STACKP (obj)); |
| 411 | } |
| 412 | #undef FUNC_NAME |
| 413 | |
| 414 | SCM_DEFINE (scm_make_stack, "make-stack", 1, 0, 1, |
| 415 | (SCM obj, SCM args), |
| 416 | "Create a new stack. If @var{obj} is @code{#t}, the current\n" |
| 417 | "evaluation stack is used for creating the stack frames,\n" |
| 418 | "otherwise the frames are taken from @var{obj} (which must be\n" |
| 419 | "either a debug object or a continuation).\n" |
| 420 | "@var{args} must be a list of integers and specifies how the\n" |
| 421 | "resulting stack will be narrowed.") |
| 422 | #define FUNC_NAME s_scm_make_stack |
| 423 | { |
| 424 | int n, maxp, size; |
| 425 | scm_debug_frame *dframe = scm_last_debug_frame; |
| 426 | scm_info_frame *iframe; |
| 427 | long offset = 0; |
| 428 | SCM stack, id; |
| 429 | SCM inner_cut, outer_cut; |
| 430 | |
| 431 | /* Extract a pointer to the innermost frame of whatever object |
| 432 | scm_make_stack was given. */ |
| 433 | /* just use dframe == scm_last_debug_frame |
| 434 | (from initialization of dframe, above) if obj is #t */ |
| 435 | if (!SCM_EQ_P (obj, SCM_BOOL_T)) |
| 436 | { |
| 437 | SCM_ASSERT (SCM_NIMP (obj), obj, SCM_ARG1, FUNC_NAME); |
| 438 | if (SCM_DEBUGOBJP (obj)) |
| 439 | dframe = (scm_debug_frame *) SCM_DEBUGOBJ_FRAME (obj); |
| 440 | else if (SCM_CONTINUATIONP (obj)) |
| 441 | { |
| 442 | offset = ((SCM_STACKITEM *) ((char *) SCM_CONTREGS (obj) + sizeof (scm_contregs)) |
| 443 | - SCM_BASE (obj)); |
| 444 | #ifndef STACK_GROWS_UP |
| 445 | offset += SCM_CONTINUATION_LENGTH (obj); |
| 446 | #endif |
| 447 | dframe = RELOC_FRAME (SCM_DFRAME (obj), offset); |
| 448 | } |
| 449 | else |
| 450 | { |
| 451 | SCM_WRONG_TYPE_ARG (SCM_ARG1, obj); |
| 452 | /* not reached */ |
| 453 | } |
| 454 | } |
| 455 | |
| 456 | /* Count number of frames. Also get stack id tag and check whether |
| 457 | there are more stackframes than we want to record |
| 458 | (SCM_BACKTRACE_MAXDEPTH). */ |
| 459 | id = SCM_BOOL_F; |
| 460 | maxp = 0; |
| 461 | n = stack_depth (dframe, offset, &id, &maxp); |
| 462 | size = n * SCM_FRAME_N_SLOTS; |
| 463 | |
| 464 | /* Make the stack object. */ |
| 465 | stack = scm_make_struct (scm_stack_type, SCM_MAKINUM (size), SCM_EOL); |
| 466 | SCM_STACK (stack) -> id = id; |
| 467 | iframe = &SCM_STACK (stack) -> tail[0]; |
| 468 | SCM_STACK (stack) -> frames = iframe; |
| 469 | |
| 470 | /* Translate the current chain of stack frames into debugging information. */ |
| 471 | n = read_frames (RELOC_FRAME (dframe, offset), offset, n, iframe); |
| 472 | SCM_STACK (stack) -> length = n; |
| 473 | |
| 474 | /* Narrow the stack according to the arguments given to scm_make_stack. */ |
| 475 | SCM_VALIDATE_REST_ARGUMENT (args); |
| 476 | while (n > 0 && !SCM_NULLP (args)) |
| 477 | { |
| 478 | inner_cut = SCM_CAR (args); |
| 479 | args = SCM_CDR (args); |
| 480 | if (SCM_NULLP (args)) |
| 481 | { |
| 482 | outer_cut = SCM_INUM0; |
| 483 | } |
| 484 | else |
| 485 | { |
| 486 | outer_cut = SCM_CAR (args); |
| 487 | args = SCM_CDR (args); |
| 488 | } |
| 489 | |
| 490 | narrow_stack (stack, |
| 491 | SCM_INUMP (inner_cut) ? SCM_INUM (inner_cut) : n, |
| 492 | SCM_INUMP (inner_cut) ? 0 : inner_cut, |
| 493 | SCM_INUMP (outer_cut) ? SCM_INUM (outer_cut) : n, |
| 494 | SCM_INUMP (outer_cut) ? 0 : outer_cut); |
| 495 | |
| 496 | n = SCM_STACK (stack) -> length; |
| 497 | } |
| 498 | |
| 499 | if (n > 0) |
| 500 | { |
| 501 | if (maxp) |
| 502 | iframe[n - 1].flags |= SCM_FRAMEF_OVERFLOW; |
| 503 | return stack; |
| 504 | } |
| 505 | else |
| 506 | return SCM_BOOL_F; |
| 507 | } |
| 508 | #undef FUNC_NAME |
| 509 | |
| 510 | SCM_DEFINE (scm_stack_id, "stack-id", 1, 0, 0, |
| 511 | (SCM stack), |
| 512 | "Return the identifier given to @var{stack} by @code{start-stack}.") |
| 513 | #define FUNC_NAME s_scm_stack_id |
| 514 | { |
| 515 | scm_debug_frame *dframe; |
| 516 | long offset = 0; |
| 517 | if (SCM_EQ_P (stack, SCM_BOOL_T)) |
| 518 | dframe = scm_last_debug_frame; |
| 519 | else |
| 520 | { |
| 521 | SCM_VALIDATE_NIM (1,stack); |
| 522 | if (SCM_DEBUGOBJP (stack)) |
| 523 | dframe = (scm_debug_frame *) SCM_DEBUGOBJ_FRAME (stack); |
| 524 | else if (SCM_CONTINUATIONP (stack)) |
| 525 | { |
| 526 | offset = ((SCM_STACKITEM *) ((char *) SCM_CONTREGS (stack) + sizeof (scm_contregs)) |
| 527 | - SCM_BASE (stack)); |
| 528 | #ifndef STACK_GROWS_UP |
| 529 | offset += SCM_CONTINUATION_LENGTH (stack); |
| 530 | #endif |
| 531 | dframe = RELOC_FRAME (SCM_DFRAME (stack), offset); |
| 532 | } |
| 533 | else if (SCM_STACKP (stack)) |
| 534 | return SCM_STACK (stack) -> id; |
| 535 | else |
| 536 | SCM_WRONG_TYPE_ARG (1, stack); |
| 537 | } |
| 538 | while (dframe && !SCM_VOIDFRAMEP (*dframe)) |
| 539 | dframe = RELOC_FRAME (dframe->prev, offset); |
| 540 | if (dframe && SCM_VOIDFRAMEP (*dframe)) |
| 541 | return dframe->vect[0].id; |
| 542 | return SCM_BOOL_F; |
| 543 | } |
| 544 | #undef FUNC_NAME |
| 545 | |
| 546 | SCM_DEFINE (scm_stack_ref, "stack-ref", 2, 0, 0, |
| 547 | (SCM stack, SCM i), |
| 548 | "Return the @var{i}'th frame from @var{stack}.") |
| 549 | #define FUNC_NAME s_scm_stack_ref |
| 550 | { |
| 551 | SCM_VALIDATE_STACK (1,stack); |
| 552 | SCM_VALIDATE_INUM (2,i); |
| 553 | SCM_ASSERT_RANGE (1,i, |
| 554 | SCM_INUM (i) >= 0 && |
| 555 | SCM_INUM (i) < SCM_STACK_LENGTH (stack)); |
| 556 | return scm_cons (stack, i); |
| 557 | } |
| 558 | #undef FUNC_NAME |
| 559 | |
| 560 | SCM_DEFINE (scm_stack_length, "stack-length", 1, 0, 0, |
| 561 | (SCM stack), |
| 562 | "Return the length of @var{stack}.") |
| 563 | #define FUNC_NAME s_scm_stack_length |
| 564 | { |
| 565 | SCM_VALIDATE_STACK (1,stack); |
| 566 | return SCM_MAKINUM (SCM_STACK_LENGTH (stack)); |
| 567 | } |
| 568 | #undef FUNC_NAME |
| 569 | |
| 570 | /* Frames |
| 571 | */ |
| 572 | |
| 573 | SCM_DEFINE (scm_frame_p, "frame?", 1, 0, 0, |
| 574 | (SCM obj), |
| 575 | "Return @code{#t} if @var{obj} is a stack frame.") |
| 576 | #define FUNC_NAME s_scm_frame_p |
| 577 | { |
| 578 | return SCM_BOOL(SCM_FRAMEP (obj)); |
| 579 | } |
| 580 | #undef FUNC_NAME |
| 581 | |
| 582 | SCM_DEFINE (scm_last_stack_frame, "last-stack-frame", 1, 0, 0, |
| 583 | (SCM obj), |
| 584 | "Return a stack which consists of a single frame, which is the\n" |
| 585 | "last stack frame for @var{obj}. @var{obj} must be either a\n" |
| 586 | "debug object or a continuation.") |
| 587 | #define FUNC_NAME s_scm_last_stack_frame |
| 588 | { |
| 589 | scm_debug_frame *dframe; |
| 590 | long offset = 0; |
| 591 | SCM stack; |
| 592 | |
| 593 | SCM_VALIDATE_NIM (1,obj); |
| 594 | if (SCM_DEBUGOBJP (obj)) |
| 595 | dframe = (scm_debug_frame *) SCM_DEBUGOBJ_FRAME (obj); |
| 596 | else if (SCM_CONTINUATIONP (obj)) |
| 597 | { |
| 598 | offset = ((SCM_STACKITEM *) ((char *) SCM_CONTREGS (obj) + sizeof (scm_contregs)) |
| 599 | - SCM_BASE (obj)); |
| 600 | #ifndef STACK_GROWS_UP |
| 601 | offset += SCM_CONTINUATION_LENGTH (obj); |
| 602 | #endif |
| 603 | dframe = RELOC_FRAME (SCM_DFRAME (obj), offset); |
| 604 | } |
| 605 | else |
| 606 | { |
| 607 | SCM_WRONG_TYPE_ARG (1, obj); |
| 608 | /* not reached */ |
| 609 | } |
| 610 | |
| 611 | if (!dframe || SCM_VOIDFRAMEP (*dframe)) |
| 612 | return SCM_BOOL_F; |
| 613 | |
| 614 | stack = scm_make_struct (scm_stack_type, SCM_MAKINUM (SCM_FRAME_N_SLOTS), |
| 615 | SCM_EOL); |
| 616 | SCM_STACK (stack) -> length = 1; |
| 617 | SCM_STACK (stack) -> frames = &SCM_STACK (stack) -> tail[0]; |
| 618 | read_frame (dframe, offset, |
| 619 | (scm_info_frame *) &SCM_STACK (stack) -> frames[0]); |
| 620 | |
| 621 | return scm_cons (stack, SCM_INUM0);; |
| 622 | } |
| 623 | #undef FUNC_NAME |
| 624 | |
| 625 | SCM_DEFINE (scm_frame_number, "frame-number", 1, 0, 0, |
| 626 | (SCM frame), |
| 627 | "Return the frame number of @var{frame}.") |
| 628 | #define FUNC_NAME s_scm_frame_number |
| 629 | { |
| 630 | SCM_VALIDATE_FRAME (1,frame); |
| 631 | return SCM_MAKINUM (SCM_FRAME_NUMBER (frame)); |
| 632 | } |
| 633 | #undef FUNC_NAME |
| 634 | |
| 635 | SCM_DEFINE (scm_frame_source, "frame-source", 1, 0, 0, |
| 636 | (SCM frame), |
| 637 | "Return the source of @var{frame}.") |
| 638 | #define FUNC_NAME s_scm_frame_source |
| 639 | { |
| 640 | SCM_VALIDATE_FRAME (1,frame); |
| 641 | return SCM_FRAME_SOURCE (frame); |
| 642 | } |
| 643 | #undef FUNC_NAME |
| 644 | |
| 645 | SCM_DEFINE (scm_frame_procedure, "frame-procedure", 1, 0, 0, |
| 646 | (SCM frame), |
| 647 | "Return the procedure for @var{frame}, or @code{#f} if no\n" |
| 648 | "procedure is associated with @var{frame}.") |
| 649 | #define FUNC_NAME s_scm_frame_procedure |
| 650 | { |
| 651 | SCM_VALIDATE_FRAME (1,frame); |
| 652 | return (SCM_FRAME_PROC_P (frame) |
| 653 | ? SCM_FRAME_PROC (frame) |
| 654 | : SCM_BOOL_F); |
| 655 | } |
| 656 | #undef FUNC_NAME |
| 657 | |
| 658 | SCM_DEFINE (scm_frame_arguments, "frame-arguments", 1, 0, 0, |
| 659 | (SCM frame), |
| 660 | "Return the arguments of @var{frame}.") |
| 661 | #define FUNC_NAME s_scm_frame_arguments |
| 662 | { |
| 663 | SCM_VALIDATE_FRAME (1,frame); |
| 664 | return SCM_FRAME_ARGS (frame); |
| 665 | } |
| 666 | #undef FUNC_NAME |
| 667 | |
| 668 | SCM_DEFINE (scm_frame_previous, "frame-previous", 1, 0, 0, |
| 669 | (SCM frame), |
| 670 | "Return the previous frame of @var{frame}, or @code{#f} if\n" |
| 671 | "@var{frame} is the first frame in its stack.") |
| 672 | #define FUNC_NAME s_scm_frame_previous |
| 673 | { |
| 674 | int n; |
| 675 | SCM_VALIDATE_FRAME (1,frame); |
| 676 | n = SCM_INUM (SCM_CDR (frame)) + 1; |
| 677 | if (n >= SCM_STACK_LENGTH (SCM_CAR (frame))) |
| 678 | return SCM_BOOL_F; |
| 679 | else |
| 680 | return scm_cons (SCM_CAR (frame), SCM_MAKINUM (n)); |
| 681 | } |
| 682 | #undef FUNC_NAME |
| 683 | |
| 684 | SCM_DEFINE (scm_frame_next, "frame-next", 1, 0, 0, |
| 685 | (SCM frame), |
| 686 | "Return the next frame of @var{frame}, or @code{#f} if\n" |
| 687 | "@var{frame} is the last frame in its stack.") |
| 688 | #define FUNC_NAME s_scm_frame_next |
| 689 | { |
| 690 | int n; |
| 691 | SCM_VALIDATE_FRAME (1,frame); |
| 692 | n = SCM_INUM (SCM_CDR (frame)) - 1; |
| 693 | if (n < 0) |
| 694 | return SCM_BOOL_F; |
| 695 | else |
| 696 | return scm_cons (SCM_CAR (frame), SCM_MAKINUM (n)); |
| 697 | } |
| 698 | #undef FUNC_NAME |
| 699 | |
| 700 | SCM_DEFINE (scm_frame_real_p, "frame-real?", 1, 0, 0, |
| 701 | (SCM frame), |
| 702 | "Return @code{#t} if @var{frame} is a real frame.") |
| 703 | #define FUNC_NAME s_scm_frame_real_p |
| 704 | { |
| 705 | SCM_VALIDATE_FRAME (1,frame); |
| 706 | return SCM_BOOL(SCM_FRAME_REAL_P (frame)); |
| 707 | } |
| 708 | #undef FUNC_NAME |
| 709 | |
| 710 | SCM_DEFINE (scm_frame_procedure_p, "frame-procedure?", 1, 0, 0, |
| 711 | (SCM frame), |
| 712 | "Return @code{#t} if a procedure is associated with @var{frame}.") |
| 713 | #define FUNC_NAME s_scm_frame_procedure_p |
| 714 | { |
| 715 | SCM_VALIDATE_FRAME (1,frame); |
| 716 | return SCM_BOOL(SCM_FRAME_PROC_P (frame)); |
| 717 | } |
| 718 | #undef FUNC_NAME |
| 719 | |
| 720 | SCM_DEFINE (scm_frame_evaluating_args_p, "frame-evaluating-args?", 1, 0, 0, |
| 721 | (SCM frame), |
| 722 | "Return @code{#t} if @var{frame} contains evaluated arguments.") |
| 723 | #define FUNC_NAME s_scm_frame_evaluating_args_p |
| 724 | { |
| 725 | SCM_VALIDATE_FRAME (1,frame); |
| 726 | return SCM_BOOL(SCM_FRAME_EVAL_ARGS_P (frame)); |
| 727 | } |
| 728 | #undef FUNC_NAME |
| 729 | |
| 730 | SCM_DEFINE (scm_frame_overflow_p, "frame-overflow?", 1, 0, 0, |
| 731 | (SCM frame), |
| 732 | "Return @code{#t} if @var{frame} is an overflow frame.") |
| 733 | #define FUNC_NAME s_scm_frame_overflow_p |
| 734 | { |
| 735 | SCM_VALIDATE_FRAME (1,frame); |
| 736 | return SCM_BOOL(SCM_FRAME_OVERFLOW_P (frame)); |
| 737 | } |
| 738 | #undef FUNC_NAME |
| 739 | |
| 740 | \f |
| 741 | |
| 742 | void |
| 743 | scm_init_stacks () |
| 744 | { |
| 745 | SCM vtable; |
| 746 | SCM stack_layout |
| 747 | = scm_make_struct_layout (scm_makfrom0str (SCM_STACK_LAYOUT)); |
| 748 | vtable = scm_make_vtable_vtable (scm_nullstr, SCM_INUM0, SCM_EOL); |
| 749 | scm_stack_type |
| 750 | = scm_permanent_object (scm_make_struct (vtable, SCM_INUM0, |
| 751 | scm_cons (stack_layout, |
| 752 | SCM_EOL))); |
| 753 | scm_set_struct_vtable_name_x (scm_stack_type, scm_str2symbol ("stack")); |
| 754 | #ifndef SCM_MAGIC_SNARFER |
| 755 | #include "libguile/stacks.x" |
| 756 | #endif |
| 757 | } |
| 758 | |
| 759 | /* |
| 760 | Local Variables: |
| 761 | c-file-style: "gnu" |
| 762 | End: |
| 763 | */ |