libguile/debug.c

   1 /* Debugging extensions for Guile
   2  * Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003, 2006, 2008 Free Software Foundation
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library 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 GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19
  20 #ifdef HAVE_CONFIG_H
  21 # include <config.h>
  22 #endif
  23
  24 #include "libguile/_scm.h"
  25 #include "libguile/async.h"
  26 #include "libguile/eval.h"
  27 #include "libguile/list.h"
  28 #include "libguile/stackchk.h"
  29 #include "libguile/throw.h"
  30 #include "libguile/macros.h"
  31 #include "libguile/smob.h"
  32 #include "libguile/procprop.h"
  33 #include "libguile/srcprop.h"
  34 #include "libguile/alist.h"
  35 #include "libguile/continuations.h"
  36 #include "libguile/strports.h"
  37 #include "libguile/read.h"
  38 #include "libguile/feature.h"
  39 #include "libguile/dynwind.h"
  40 #include "libguile/modules.h"
  41 #include "libguile/ports.h"
  42 #include "libguile/root.h"
  43 #include "libguile/fluids.h"
  44 #include "libguile/objects.h"
  45 #include "libguile/programs.h"
  46
  47 #include "libguile/validate.h"
  48 #include "libguile/debug.h"
  49
  50 #include "libguile/private-options.h"
  51 \f
  52
  53
  54 /* {Run time control of the debugging evaluator}
  55  */
  56
  57 SCM_DEFINE (scm_debug_options, "debug-options-interface", 0, 1, 0,
  58             (SCM setting),
  59             "Option interface for the debug options. Instead of using\n"
  60             "this procedure directly, use the procedures @code{debug-enable},\n"
  61             "@code{debug-disable}, @code{debug-set!} and @code{debug-options}.")
  62 #define FUNC_NAME s_scm_debug_options
  63 {
  64   SCM ans;
  65
  66   scm_dynwind_begin (0);
  67   scm_dynwind_critical_section (SCM_BOOL_F);
  68
  69   ans = scm_options (setting, scm_debug_opts, FUNC_NAME);
  70   if (!(1 <= SCM_N_FRAMES && SCM_N_FRAMES <= SCM_MAX_FRAME_SIZE))
  71     {
  72       scm_options (ans, scm_debug_opts, FUNC_NAME);
  73       SCM_OUT_OF_RANGE (1, setting);
  74     }
  75   SCM_RESET_DEBUG_MODE;
  76 #ifdef STACK_CHECKING
  77   scm_stack_checking_enabled_p = SCM_STACK_CHECKING_P;
  78 #endif
  79   scm_debug_eframe_size = 2 * SCM_N_FRAMES;
  80
  81   scm_dynwind_end ();
  82   return ans;
  83 }
  84 #undef FUNC_NAME
  85
  86
  87 static void
  88 with_traps_before (void *data)
  89 {
  90   int *trap_flag = data;
  91   *trap_flag = SCM_TRAPS_P;
  92   SCM_TRAPS_P = 1;
  93 }
  94
  95 static void
  96 with_traps_after (void *data)
  97 {
  98   int *trap_flag = data;
  99   SCM_TRAPS_P = *trap_flag;
 100 }
 101
 102 static SCM
 103 with_traps_inner (void *data)
 104 {
 105   SCM thunk = SCM_PACK ((scm_t_bits) data);
 106   return scm_call_0 (thunk);
 107 }
 108
 109 SCM_DEFINE (scm_with_traps, "with-traps", 1, 0, 0,
 110             (SCM thunk),
 111             "Call @var{thunk} with traps enabled.")
 112 #define FUNC_NAME s_scm_with_traps
 113 {
 114   int trap_flag;
 115   SCM_VALIDATE_THUNK (1, thunk);
 116   return scm_internal_dynamic_wind (with_traps_before,
 117                                     with_traps_inner,
 118                                     with_traps_after,
 119                                     (void *) SCM_UNPACK (thunk),
 120                                     &trap_flag);
 121 }
 122 #undef FUNC_NAME
 123
 124 \f
 125 SCM_SYMBOL (scm_sym_procname, "procname");
 126 SCM_SYMBOL (scm_sym_dots, "...");
 127 SCM_SYMBOL (scm_sym_source, "source");
 128
 129 /* {Memoized Source}
 130  */
 131
 132 scm_t_bits scm_tc16_memoized;
 133
 134 static int
 135 memoized_print (SCM obj, SCM port, scm_print_state *pstate)
 136 {
 137   int writingp = SCM_WRITINGP (pstate);
 138   scm_puts ("#<memoized ", port);
 139   SCM_SET_WRITINGP (pstate, 1);
 140   scm_iprin1 (SCM_MEMOIZED_EXP (obj), port, pstate);
 141   SCM_SET_WRITINGP (pstate, writingp);
 142   scm_putc ('>', port);
 143   return 1;
 144 }
 145
 146 SCM_DEFINE (scm_memoized_p, "memoized?", 1, 0, 0,
 147             (SCM obj),
 148             "Return @code{#t} if @var{obj} is memoized.")
 149 #define FUNC_NAME s_scm_memoized_p
 150 {
 151   return scm_from_bool(SCM_MEMOIZEDP (obj));
 152 }
 153 #undef FUNC_NAME
 154
 155 SCM
 156 scm_make_memoized (SCM exp, SCM env)
 157 {
 158   /* *fixme* Check that env is a valid environment. */
 159   SCM_RETURN_NEWSMOB (scm_tc16_memoized, SCM_UNPACK (scm_cons (exp, env)));
 160 }
 161
 162 #ifdef GUILE_DEBUG
 163 /*
 164  * Some primitives for construction of memoized code
 165  *
 166  * - procedure: memcons CAR CDR [ENV]
 167  *
 168  *     Construct a pair, encapsulated in a memoized object.
 169  *
 170  *     The CAR and CDR can be either normal or memoized.  If ENV isn't
 171  *     specified, the top-level environment of the current module will
 172  *     be assumed.  All environments must match.
 173  *
 174  * - procedure: make-iloc FRAME BINDING CDRP
 175  *
 176  *     Return an iloc referring to frame no. FRAME, binding
 177  *     no. BINDING.  If CDRP is non-#f, the iloc is referring to a
 178  *     frame consisting of a single pair, with the value stored in the
 179  *     CDR.
 180  *
 181  * - procedure: iloc? OBJECT
 182  *
 183  *     Return #t if OBJECT is an iloc.
 184  *
 185  * - procedure: mem->proc MEMOIZED
 186  *
 187  *     Construct a closure from the memoized lambda expression MEMOIZED
 188  *
 189  *     WARNING! The code is not copied!
 190  *
 191  * - procedure: proc->mem CLOSURE
 192  *
 193  *     Turn the closure CLOSURE into a memoized object.
 194  *
 195  *     WARNING! The code is not copied!
 196  *
 197  * - constant: SCM_IM_AND
 198  * - constant: SCM_IM_BEGIN
 199  * - constant: SCM_IM_CASE
 200  * - constant: SCM_IM_COND
 201  * - constant: SCM_IM_DO
 202  * - constant: SCM_IM_IF
 203  * - constant: SCM_IM_LAMBDA
 204  * - constant: SCM_IM_LET
 205  * - constant: SCM_IM_LETSTAR
 206  * - constant: SCM_IM_LETREC
 207  * - constant: SCM_IM_OR
 208  * - constant: SCM_IM_QUOTE
 209  * - constant: SCM_IM_SET
 210  * - constant: SCM_IM_DEFINE
 211  * - constant: SCM_IM_APPLY
 212  * - constant: SCM_IM_CONT
 213  * - constant: SCM_IM_DISPATCH
 214  */
 215
 216 #include "libguile/variable.h"
 217 #include "libguile/procs.h"
 218
 219 SCM_DEFINE (scm_memcons, "memcons", 2, 1, 0,
 220             (SCM car, SCM cdr, SCM env),
 221             "Return a new memoized cons cell with @var{car} and @var{cdr}\n"
 222             "as members and @var{env} as the environment.")
 223 #define FUNC_NAME s_scm_memcons
 224 {
 225   if (SCM_MEMOIZEDP (car))
 226     {
 227       /*fixme* environments may be two different but equal top-level envs */
 228       if (!SCM_UNBNDP (env) && SCM_MEMOIZED_ENV (car) != env)
 229         SCM_MISC_ERROR ("environment mismatch arg1 <-> arg3",
 230                         scm_list_2 (car, env));
 231       else
 232         env = SCM_MEMOIZED_ENV (car);
 233       car = SCM_MEMOIZED_EXP (car);
 234     }
 235   if (SCM_MEMOIZEDP (cdr))
 236     {
 237       if (!SCM_UNBNDP (env) && SCM_MEMOIZED_ENV (cdr) != env)
 238         SCM_MISC_ERROR ("environment mismatch arg2 <-> arg3",
 239                         scm_list_2 (cdr, env));
 240       else
 241         env = SCM_MEMOIZED_ENV (cdr);
 242       cdr = SCM_MEMOIZED_EXP (cdr);
 243     }
 244   if (SCM_UNBNDP (env))
 245     env = scm_top_level_env (SCM_TOP_LEVEL_LOOKUP_CLOSURE);
 246   else
 247     SCM_VALIDATE_NULLORCONS (3, env);
 248   return scm_make_memoized (scm_cons (car, cdr), env);
 249 }
 250 #undef FUNC_NAME
 251
 252 SCM_DEFINE (scm_mem_to_proc, "mem->proc", 1, 0, 0,
 253             (SCM obj),
 254             "Convert a memoized object (which must represent a body)\n"
 255             "to a procedure.")
 256 #define FUNC_NAME s_scm_mem_to_proc
 257 {
 258   SCM env;
 259   SCM_VALIDATE_MEMOIZED (1, obj);
 260   env = SCM_MEMOIZED_ENV (obj);
 261   obj = SCM_MEMOIZED_EXP (obj);
 262   return scm_closure (obj, env);
 263 }
 264 #undef FUNC_NAME
 265
 266 SCM_DEFINE (scm_proc_to_mem, "proc->mem", 1, 0, 0,
 267             (SCM obj),
 268             "Convert a procedure to a memoized object.")
 269 #define FUNC_NAME s_scm_proc_to_mem
 270 {
 271   SCM_VALIDATE_CLOSURE (1, obj);
 272   return scm_make_memoized (SCM_CODE (obj), SCM_ENV (obj));
 273 }
 274 #undef FUNC_NAME
 275
 276 #endif /* GUILE_DEBUG */
 277
 278 SCM_DEFINE (scm_i_unmemoize_expr, "unmemoize-expr", 1, 0, 0,
 279             (SCM m),
 280             "Unmemoize the memoized expression @var{m},")
 281 #define FUNC_NAME s_scm_i_unmemoize_expr
 282 {
 283   SCM_VALIDATE_MEMOIZED (1, m);
 284   return scm_i_unmemocopy_expr (SCM_MEMOIZED_EXP (m), SCM_MEMOIZED_ENV (m));
 285 }
 286 #undef FUNC_NAME
 287
 288 SCM_DEFINE (scm_memoized_environment, "memoized-environment", 1, 0, 0,
 289             (SCM m),
 290             "Return the environment of the memoized expression @var{m}.")
 291 #define FUNC_NAME s_scm_memoized_environment
 292 {
 293   SCM_VALIDATE_MEMOIZED (1, m);
 294   return SCM_MEMOIZED_ENV (m);
 295 }
 296 #undef FUNC_NAME
 297
 298 SCM_DEFINE (scm_procedure_name, "procedure-name", 1, 0, 0,
 299             (SCM proc),
 300             "Return the name of the procedure @var{proc}")
 301 #define FUNC_NAME s_scm_procedure_name
 302 {
 303   SCM_VALIDATE_PROC (1, proc);
 304   switch (SCM_TYP7 (proc)) {
 305   case scm_tcs_subrs:
 306     return SCM_SNAME (proc);
 307   default:
 308     {
 309       SCM name = scm_procedure_property (proc, scm_sym_name);
 310 #if 0
 311       /* Source property scm_sym_procname not implemented yet... */
 312       SCM name = scm_source_property (SCM_CAR (SCM_CLOSURE_BODY (proc)), scm_sym_procname);
 313       if (scm_is_false (name))
 314         name = scm_procedure_property (proc, scm_sym_name);
 315 #endif
 316       if (scm_is_false (name) && SCM_CLOSUREP (proc))
 317         name = scm_reverse_lookup (SCM_ENV (proc), proc);
 318       if (scm_is_false (name) && SCM_PROGRAM_P (proc))
 319         name = scm_program_name (proc);
 320       return name;
 321     }
 322   }
 323 }
 324 #undef FUNC_NAME
 325
 326 SCM_DEFINE (scm_procedure_source, "procedure-source", 1, 0, 0,
 327             (SCM proc),
 328             "Return the source of the procedure @var{proc}.")
 329 #define FUNC_NAME s_scm_procedure_source
 330 {
 331   SCM_VALIDATE_NIM (1, proc);
 332  again:
 333   switch (SCM_TYP7 (proc)) {
 334   case scm_tcs_closures:
 335     {
 336       const SCM formals = SCM_CLOSURE_FORMALS (proc);
 337       const SCM body = SCM_CLOSURE_BODY (proc);
 338       const SCM src = scm_source_property (body, scm_sym_copy);
 339
 340       if (scm_is_true (src))
 341         {
 342           return scm_cons2 (scm_sym_lambda, formals, src);
 343         }
 344       else
 345         {
 346           const SCM env = SCM_EXTEND_ENV (formals, SCM_EOL, SCM_ENV (proc));
 347           return scm_cons2 (scm_sym_lambda,
 348                             scm_i_finite_list_copy (formals),
 349                             scm_i_unmemocopy_body (body, env));
 350         }
 351     }
 352   case scm_tcs_struct:
 353     if (!SCM_I_OPERATORP (proc))
 354       break;
 355     goto procprop;
 356   case scm_tc7_smob:
 357     if (!SCM_SMOB_DESCRIPTOR (proc).apply)
 358       break;
 359   case scm_tcs_subrs:
 360 #ifdef CCLO
 361   case scm_tc7_cclo:
 362 #endif
 363   procprop:
 364     /* It would indeed be a nice thing if we supplied source even for
 365        built in procedures! */
 366     return scm_procedure_property (proc, scm_sym_source);
 367   case scm_tc7_pws:
 368     {
 369       SCM src = scm_procedure_property (proc, scm_sym_source);
 370       if (scm_is_true (src))
 371         return src;
 372       proc = SCM_PROCEDURE (proc);
 373       goto again;
 374     }
 375   default:
 376     ;
 377   }
 378   SCM_WRONG_TYPE_ARG (1, proc);
 379   return SCM_BOOL_F; /* not reached */
 380 }
 381 #undef FUNC_NAME
 382
 383 SCM_DEFINE (scm_procedure_environment, "procedure-environment", 1, 0, 0,
 384             (SCM proc),
 385             "Return the environment of the procedure @var{proc}.")
 386 #define FUNC_NAME s_scm_procedure_environment
 387 {
 388   SCM_VALIDATE_NIM (1, proc);
 389   switch (SCM_TYP7 (proc)) {
 390   case scm_tcs_closures:
 391     return SCM_ENV (proc);
 392   case scm_tcs_subrs:
 393 #ifdef CCLO
 394   case scm_tc7_cclo:
 395 #endif
 396     return SCM_EOL;
 397   default:
 398     SCM_WRONG_TYPE_ARG (1, proc);
 399     /* not reached */
 400   }
 401 }
 402 #undef FUNC_NAME
 403
 404 \f
 405
 406 /* Eval in a local environment.  We would like to have the ability to
 407  * evaluate in a specified local environment, but due to the
 408  * memoization this isn't normally possible.  We solve it by copying
 409  * the code before evaluating.  One solution would be to have eval.c
 410  * generate yet another evaluator.  They are not very big actually.
 411  */
 412 SCM_DEFINE (scm_local_eval, "local-eval", 1, 1, 0,
 413             (SCM exp, SCM env),
 414             "Evaluate @var{exp} in its environment.  If @var{env} is supplied,\n"
 415             "it is the environment in which to evaluate @var{exp}.  Otherwise,\n"
 416             "@var{exp} must be a memoized code object (in which case, its environment\n"
 417             "is implicit).")
 418 #define FUNC_NAME s_scm_local_eval
 419 {
 420   if (SCM_UNBNDP (env))
 421   {
 422     SCM_VALIDATE_MEMOIZED (1, exp);
 423     return scm_i_eval_x (SCM_MEMOIZED_EXP (exp), SCM_MEMOIZED_ENV (exp));
 424   }
 425   return scm_i_eval (exp, env);
 426 }
 427 #undef FUNC_NAME
 428
 429 #if 0
 430 SCM_REGISTER_PROC (s_reverse_lookup, "reverse-lookup", 2, 0, 0, scm_reverse_lookup);
 431 #endif
 432
 433 SCM
 434 scm_reverse_lookup (SCM env, SCM data)
 435 {
 436   while (scm_is_pair (env) && scm_is_pair (SCM_CAR (env)))
 437     {
 438       SCM names = SCM_CAAR (env);
 439       SCM values = SCM_CDAR (env);
 440       while (scm_is_pair (names))
 441         {
 442           if (scm_is_eq (SCM_CAR (values), data))
 443             return SCM_CAR (names);
 444           names = SCM_CDR (names);
 445           values = SCM_CDR (values);
 446         }
 447       if (!scm_is_null (names) && scm_is_eq (values, data))
 448         return names;
 449       env = SCM_CDR (env);
 450     }
 451   return SCM_BOOL_F;
 452 }
 453
 454 SCM_DEFINE (scm_sys_start_stack, "%start-stack", 2, 0, 0,
 455             (SCM id, SCM thunk),
 456             "Call @var{thunk} on an evaluator stack tagged with @var{id}.")
 457 #define FUNC_NAME s_scm_sys_start_stack
 458 {
 459   SCM answer;
 460   scm_t_debug_frame vframe;
 461   scm_t_debug_info vframe_vect_body;
 462   vframe.prev = scm_i_last_debug_frame ();
 463   vframe.status = SCM_VOIDFRAME;
 464   vframe.vect = &vframe_vect_body;
 465   vframe.vect[0].id = id;
 466   scm_i_set_last_debug_frame (&vframe);
 467   answer = scm_call_0 (thunk);
 468   scm_i_set_last_debug_frame (vframe.prev);
 469   return answer;
 470 }
 471 #undef FUNC_NAME
 472
 473 /* {Debug Objects}
 474  *
 475  * The debugging evaluator throws these on frame traps.
 476  */
 477
 478 scm_t_bits scm_tc16_debugobj;
 479
 480 static int
 481 debugobj_print (SCM obj, SCM port, scm_print_state *pstate SCM_UNUSED)
 482 {
 483   scm_puts ("#<debug-object ", port);
 484   scm_intprint ((long) SCM_DEBUGOBJ_FRAME (obj), 16, port);
 485   scm_putc ('>', port);
 486   return 1;
 487 }
 488
 489 SCM_DEFINE (scm_debug_object_p, "debug-object?", 1, 0, 0,
 490             (SCM obj),
 491             "Return @code{#t} if @var{obj} is a debug object.")
 492 #define FUNC_NAME s_scm_debug_object_p
 493 {
 494   return scm_from_bool(SCM_DEBUGOBJP (obj));
 495 }
 496 #undef FUNC_NAME
 497
 498
 499 SCM
 500 scm_make_debugobj (scm_t_debug_frame *frame)
 501 {
 502   return scm_cell (scm_tc16_debugobj, (scm_t_bits) frame);
 503 }
 504
 505 \f
 506
 507 /* Undocumented debugging procedure */
 508 #ifdef GUILE_DEBUG
 509 SCM_DEFINE (scm_debug_hang, "debug-hang", 0, 1, 0,
 510             (SCM obj),
 511             "Go into an endless loop, which can be only terminated with\n"
 512             "a debugger.")
 513 #define FUNC_NAME s_scm_debug_hang
 514 {
 515   int go = 0;
 516   while (!go) ;
 517   return SCM_UNSPECIFIED;
 518 }
 519 #undef FUNC_NAME
 520 #endif
 521
 522 \f
 523
 524 void
 525 scm_init_debug ()
 526 {
 527   scm_init_opts (scm_debug_options, scm_debug_opts);
 528
 529   scm_tc16_memoized = scm_make_smob_type ("memoized", 0);
 530   scm_set_smob_mark (scm_tc16_memoized, scm_markcdr);
 531   scm_set_smob_print (scm_tc16_memoized, memoized_print);
 532
 533   scm_tc16_debugobj = scm_make_smob_type ("debug-object", 0);
 534   scm_set_smob_print (scm_tc16_debugobj, debugobj_print);
 535
 536 #ifdef GUILE_DEBUG
 537   scm_c_define ("SCM_IM_AND", SCM_IM_AND);
 538   scm_c_define ("SCM_IM_BEGIN", SCM_IM_BEGIN);
 539   scm_c_define ("SCM_IM_CASE", SCM_IM_CASE);
 540   scm_c_define ("SCM_IM_COND", SCM_IM_COND);
 541   scm_c_define ("SCM_IM_DO", SCM_IM_DO);
 542   scm_c_define ("SCM_IM_IF", SCM_IM_IF);
 543   scm_c_define ("SCM_IM_LAMBDA", SCM_IM_LAMBDA);
 544   scm_c_define ("SCM_IM_LET", SCM_IM_LET);
 545   scm_c_define ("SCM_IM_LETSTAR", SCM_IM_LETSTAR);
 546   scm_c_define ("SCM_IM_LETREC", SCM_IM_LETREC);
 547   scm_c_define ("SCM_IM_OR", SCM_IM_OR);
 548   scm_c_define ("SCM_IM_QUOTE", SCM_IM_QUOTE);
 549   scm_c_define ("SCM_IM_SET_X", SCM_IM_SET_X);
 550   scm_c_define ("SCM_IM_DEFINE", SCM_IM_DEFINE);
 551   scm_c_define ("SCM_IM_APPLY", SCM_IM_APPLY);
 552   scm_c_define ("SCM_IM_CONT", SCM_IM_CONT);
 553   scm_c_define ("SCM_IM_DISPATCH", SCM_IM_DISPATCH);
 554 #endif
 555   scm_add_feature ("debug-extensions");
 556
 557 #include "libguile/debug.x"
 558 }
 559
 560 /*
 561   Local Variables:
 562   c-file-style: "gnu"
 563   End:
 564 */