libguile/smob.c

   1 /*      Copyright (C) 1995, 1996, 1998, 1999, 2000 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  43    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  44
  45 \f
  46
  47 #include <stdio.h>
  48 #include "libguile/_scm.h"
  49
  50 #include "libguile/objects.h"
  51 #include "libguile/ports.h"
  52
  53 #ifdef HAVE_MALLOC_H
  54 #include <malloc.h>
  55 #endif
  56
  57 #include "libguile/smob.h"
  58
  59 \f
  60
  61 /* scm_smobs scm_numsmob
  62  * implement a dynamicly resized array of smob records.
  63  * Indexes into this table are used when generating type
  64  * tags for smobjects (if you know a tag you can get an index and conversely).
  65  */
  66 int scm_numsmob;
  67 scm_smob_descriptor *scm_smobs;
  68
  69 /* {Mark}
  70  */
  71
  72 /* This function is vestigial.  It used to be the mark function's
  73    responsibility to set the mark bit on the smob or port, but now the
  74    generic marking routine in gc.c takes care of that, and a zero
  75    pointer for a mark function means "don't bother".  So you never
  76    need scm_mark0.
  77
  78    However, we leave it here because it's harmless to call it, and
  79    people out there have smob code that uses it, and there's no reason
  80    to make their links fail.  */
  81
  82 SCM
  83 scm_mark0 (SCM ptr)
  84 {
  85   return SCM_BOOL_F;
  86 }
  87
  88 SCM
  89 scm_markcdr (SCM ptr)
  90 {
  91   return SCM_CDR (ptr);
  92 }
  93
  94 /* {Free}
  95  */
  96
  97 scm_sizet
  98 scm_free0 (SCM ptr)
  99 {
 100   return 0;
 101 }
 102
 103 scm_sizet
 104 scm_smob_free (SCM obj)
 105 {
 106   scm_must_free ((char *) SCM_CELL_WORD_1 (obj));
 107   return scm_smobs[SCM_SMOBNUM (obj)].size;
 108 }
 109
 110 /* {Print}
 111  */
 112
 113 int
 114 scm_smob_print (SCM exp, SCM port, scm_print_state *pstate)
 115 {
 116   int n = SCM_SMOBNUM (exp);
 117   scm_puts ("#<", port);
 118   scm_puts (SCM_SMOBNAME (n) ? SCM_SMOBNAME (n) : "smob", port);
 119   scm_putc (' ', port);
 120   scm_intprint (SCM_UNPACK (scm_smobs[n].size ? SCM_CDR (exp) : exp), 16, port);
 121   scm_putc ('>', port);
 122   return 1;
 123 }
 124
 125 /* {Apply}
 126  */
 127
 128 #define SCM_SMOB_APPLY0(SMOB) \
 129   SCM_SMOB_DESCRIPTOR (SMOB).apply (SMOB)
 130 #define SCM_SMOB_APPLY1(SMOB,A1) \
 131   SCM_SMOB_DESCRIPTOR (SMOB).apply (SMOB, A1)
 132 #define SCM_SMOB_APPLY2(SMOB,A1,A2) \
 133   SCM_SMOB_DESCRIPTOR (SMOB).apply (SMOB, A1, A2)
 134 #define SCM_SMOB_APPLY3(SMOB,A1,A2,A3) \
 135   SCM_SMOB_DESCRIPTOR (SMOB).apply (SMOB, A1, A2, A3)
 136
 137 static SCM
 138 scm_smob_apply_0_000 (SCM smob)
 139 {
 140   return SCM_SMOB_APPLY0 (smob);
 141 }
 142
 143 static SCM
 144 scm_smob_apply_0_010 (SCM smob)
 145 {
 146   return SCM_SMOB_APPLY1 (smob, SCM_UNDEFINED);
 147 }
 148
 149 static SCM
 150 scm_smob_apply_0_020 (SCM smob)
 151 {
 152   return SCM_SMOB_APPLY2 (smob, SCM_UNDEFINED, SCM_UNDEFINED);
 153 }
 154
 155 static SCM
 156 scm_smob_apply_0_030 (SCM smob)
 157 {
 158   return SCM_SMOB_APPLY3 (smob, SCM_UNDEFINED, SCM_UNDEFINED, SCM_UNDEFINED);
 159 }
 160
 161 static SCM
 162 scm_smob_apply_0_001 (SCM smob)
 163 {
 164   return SCM_SMOB_APPLY1 (smob, SCM_EOL);
 165 }
 166
 167 static SCM
 168 scm_smob_apply_0_011 (SCM smob)
 169 {
 170   return SCM_SMOB_APPLY2 (smob, SCM_UNDEFINED, SCM_EOL);
 171 }
 172
 173 static SCM
 174 scm_smob_apply_0_021 (SCM smob)
 175 {
 176   return SCM_SMOB_APPLY3 (smob, SCM_UNDEFINED, SCM_UNDEFINED, SCM_EOL);
 177 }
 178
 179 static SCM
 180 scm_smob_apply_0_error (SCM smob)
 181 {
 182   scm_wrong_num_args (smob);
 183 }
 184
 185 static SCM
 186 scm_smob_apply_1_010 (SCM smob, SCM a1)
 187 {
 188   return SCM_SMOB_APPLY1 (smob, a1);
 189 }
 190
 191 static SCM
 192 scm_smob_apply_1_020 (SCM smob, SCM a1)
 193 {
 194   return SCM_SMOB_APPLY2 (smob, a1, SCM_UNDEFINED);
 195 }
 196
 197 static SCM
 198 scm_smob_apply_1_030 (SCM smob, SCM a1)
 199 {
 200   return SCM_SMOB_APPLY3 (smob, a1, SCM_UNDEFINED, SCM_UNDEFINED);
 201 }
 202
 203 static SCM
 204 scm_smob_apply_1_001 (SCM smob, SCM a1)
 205 {
 206   return SCM_SMOB_APPLY1 (smob, SCM_LIST1 (a1));
 207 }
 208
 209 static SCM
 210 scm_smob_apply_1_011 (SCM smob, SCM a1)
 211 {
 212   return SCM_SMOB_APPLY2 (smob, a1, SCM_EOL);
 213 }
 214
 215 static SCM
 216 scm_smob_apply_1_021 (SCM smob, SCM a1)
 217 {
 218   return SCM_SMOB_APPLY3 (smob, a1, SCM_UNDEFINED, SCM_EOL);
 219 }
 220
 221 static SCM
 222 scm_smob_apply_1_error (SCM smob, SCM a1)
 223 {
 224   scm_wrong_num_args (smob);
 225 }
 226
 227 static SCM
 228 scm_smob_apply_2_020 (SCM smob, SCM a1, SCM a2)
 229 {
 230   return SCM_SMOB_APPLY2 (smob, a1, a2);
 231 }
 232
 233 static SCM
 234 scm_smob_apply_2_030 (SCM smob, SCM a1, SCM a2)
 235 {
 236   return SCM_SMOB_APPLY3 (smob, a1, a2, SCM_UNDEFINED);
 237 }
 238
 239 static SCM
 240 scm_smob_apply_2_001 (SCM smob, SCM a1, SCM a2)
 241 {
 242   return SCM_SMOB_APPLY1 (smob, SCM_LIST2 (a1, a2));
 243     }
 244
 245 static SCM
 246 scm_smob_apply_2_011 (SCM smob, SCM a1, SCM a2)
 247 {
 248   return SCM_SMOB_APPLY2 (smob, a1, SCM_LIST1 (a2));
 249 }
 250
 251 static SCM
 252 scm_smob_apply_2_021 (SCM smob, SCM a1, SCM a2)
 253 {
 254   return SCM_SMOB_APPLY3 (smob, a1, a2, SCM_EOL);
 255 }
 256
 257 static SCM
 258 scm_smob_apply_2_error (SCM smob, SCM a1, SCM a2)
 259 {
 260   scm_wrong_num_args (smob);
 261 }
 262
 263 static SCM
 264 scm_smob_apply_3_030 (SCM smob, SCM a1, SCM a2, SCM rst)
 265 {
 266   if (!SCM_NULLP (SCM_CDR (rst)))
 267     scm_wrong_num_args (smob);
 268   return SCM_SMOB_APPLY3 (smob, a1, a2, SCM_CAR (rst));
 269 }
 270
 271 static SCM
 272 scm_smob_apply_3_001 (SCM smob, SCM a1, SCM a2, SCM rst)
 273 {
 274   return SCM_SMOB_APPLY1 (smob, scm_cons2 (a1, a2, rst));
 275 }
 276
 277 static SCM
 278 scm_smob_apply_3_011 (SCM smob, SCM a1, SCM a2, SCM rst)
 279 {
 280   return SCM_SMOB_APPLY2 (smob, a1, scm_cons (a2, rst));
 281 }
 282
 283 static SCM
 284 scm_smob_apply_3_021 (SCM smob, SCM a1, SCM a2, SCM rst)
 285 {
 286   return SCM_SMOB_APPLY3 (smob, a1, a2, rst);
 287 }
 288
 289 static SCM
 290 scm_smob_apply_3_error (SCM smob, SCM a1, SCM a2, SCM rst)
 291 {
 292   scm_wrong_num_args (smob);
 293 }
 294
 295 \f
 296 long
 297 scm_make_smob_type (char *name, scm_sizet size)
 298 {
 299   char *tmp;
 300   if (255 <= scm_numsmob)
 301     goto smoberr;
 302   SCM_DEFER_INTS;
 303   SCM_SYSCALL (tmp = (char *) realloc ((char *) scm_smobs,
 304                                        (1 + scm_numsmob)
 305                                        * sizeof (scm_smob_descriptor)));
 306   if (tmp)
 307     {
 308       scm_smobs = (scm_smob_descriptor *) tmp;
 309       scm_smobs[scm_numsmob].name = name;
 310       scm_smobs[scm_numsmob].size = size;
 311       scm_smobs[scm_numsmob].mark = 0;
 312       scm_smobs[scm_numsmob].free = (size == 0 ? scm_free0 : scm_smob_free);
 313       scm_smobs[scm_numsmob].print = scm_smob_print;
 314       scm_smobs[scm_numsmob].equalp = 0;
 315       scm_smobs[scm_numsmob].apply = 0;
 316       scm_smobs[scm_numsmob].apply_0 = 0;
 317       scm_smobs[scm_numsmob].apply_1 = 0;
 318       scm_smobs[scm_numsmob].apply_2 = 0;
 319       scm_smobs[scm_numsmob].apply_3 = 0;
 320       scm_smobs[scm_numsmob].gsubr_type = 0;
 321       scm_numsmob++;
 322     }
 323   SCM_ALLOW_INTS;
 324   if (!tmp)
 325     {
 326     smoberr:
 327       scm_memory_error ("scm_make_smob_type");
 328     }
 329   /* Make a class object if Goops is present. */
 330   if (scm_smob_class)
 331     scm_smob_class[scm_numsmob - 1]
 332       = scm_make_extended_class (SCM_SMOBNAME (scm_numsmob - 1));
 333   return scm_tc7_smob + (scm_numsmob - 1) * 256;
 334 }
 335
 336 long
 337 scm_make_smob_type_mfpe (char *name, scm_sizet size,
 338                         SCM (*mark) (SCM),
 339                         scm_sizet (*free) (SCM),
 340                         int (*print) (SCM, SCM, scm_print_state *),
 341                         SCM (*equalp) (SCM, SCM))
 342 {
 343   long answer = scm_make_smob_type (name, size);
 344   scm_set_smob_mfpe (answer, mark, free, print, equalp);
 345   return answer;
 346 }
 347
 348 void
 349 scm_set_smob_mark (long tc, SCM (*mark) (SCM))
 350 {
 351   scm_smobs[SCM_TC2SMOBNUM (tc)].mark = mark;
 352 }
 353
 354 void
 355 scm_set_smob_free (long tc, scm_sizet (*free) (SCM))
 356 {
 357   scm_smobs[SCM_TC2SMOBNUM (tc)].free = free;
 358 }
 359
 360 void
 361 scm_set_smob_print (long tc, int (*print) (SCM, SCM, scm_print_state*))
 362 {
 363   scm_smobs[SCM_TC2SMOBNUM (tc)].print = print;
 364 }
 365
 366 void
 367 scm_set_smob_equalp (long tc, SCM (*equalp) (SCM, SCM))
 368 {
 369   scm_smobs[SCM_TC2SMOBNUM (tc)].equalp = equalp;
 370 }
 371
 372 void
 373 scm_set_smob_apply (long tc, SCM (*apply) (), int req, int opt, int rst)
 374 {
 375   SCM (*apply_0) (SCM);
 376   SCM (*apply_1) (SCM, SCM);
 377   SCM (*apply_2) (SCM, SCM, SCM);
 378   SCM (*apply_3) (SCM, SCM, SCM, SCM);
 379   int type = SCM_GSUBR_MAKTYPE (req, opt, rst);
 380
 381   if (!(req >= 0 && opt >= 0 && (rst == 0 || rst == 1)
 382         && req + opt + rst <= 3))
 383     {
 384       puts ("Unsupported smob application type");
 385       abort ();
 386     }
 387
 388   switch (type)
 389     {
 390     case SCM_GSUBR_MAKTYPE (0, 0, 0):
 391       apply_0 = scm_smob_apply_0_000; break;
 392     case SCM_GSUBR_MAKTYPE (0, 1, 0):
 393       apply_0 = scm_smob_apply_0_010; break;
 394     case SCM_GSUBR_MAKTYPE (0, 2, 0):
 395       apply_0 = scm_smob_apply_0_020; break;
 396     case SCM_GSUBR_MAKTYPE (0, 3, 0):
 397       apply_0 = scm_smob_apply_0_030; break;
 398     case SCM_GSUBR_MAKTYPE (0, 0, 1):
 399       apply_0 = scm_smob_apply_0_001; break;
 400     case SCM_GSUBR_MAKTYPE (0, 1, 1):
 401       apply_0 = scm_smob_apply_0_011; break;
 402     case SCM_GSUBR_MAKTYPE (0, 2, 1):
 403       apply_0 = scm_smob_apply_0_021; break;
 404     default:
 405       apply_0 = scm_smob_apply_0_error; break;
 406     }
 407
 408   switch (type)
 409     {
 410     case SCM_GSUBR_MAKTYPE (1, 0, 0):
 411     case SCM_GSUBR_MAKTYPE (0, 1, 0):
 412       apply_1 = scm_smob_apply_1_010; break;
 413     case SCM_GSUBR_MAKTYPE (1, 1, 0):
 414     case SCM_GSUBR_MAKTYPE (0, 2, 0):
 415       apply_1 = scm_smob_apply_1_020; break;
 416     case SCM_GSUBR_MAKTYPE (1, 2, 0):
 417     case SCM_GSUBR_MAKTYPE (0, 3, 0):
 418       apply_1 = scm_smob_apply_1_030; break;
 419     case SCM_GSUBR_MAKTYPE (0, 0, 1):
 420       apply_1 = scm_smob_apply_1_001; break;
 421     case SCM_GSUBR_MAKTYPE (1, 0, 1):
 422     case SCM_GSUBR_MAKTYPE (0, 1, 1):
 423       apply_1 = scm_smob_apply_1_011; break;
 424     case SCM_GSUBR_MAKTYPE (1, 1, 1):
 425     case SCM_GSUBR_MAKTYPE (0, 2, 1):
 426       apply_1 = scm_smob_apply_1_021; break;
 427     default:
 428       apply_1 = scm_smob_apply_1_error; break;
 429     }
 430
 431   switch (type)
 432     {
 433     case SCM_GSUBR_MAKTYPE (2, 0, 0):
 434     case SCM_GSUBR_MAKTYPE (1, 1, 0):
 435     case SCM_GSUBR_MAKTYPE (0, 2, 0):
 436       apply_2 = scm_smob_apply_2_020; break;
 437     case SCM_GSUBR_MAKTYPE (2, 1, 0):
 438     case SCM_GSUBR_MAKTYPE (1, 2, 0):
 439     case SCM_GSUBR_MAKTYPE (0, 3, 0):
 440       apply_2 = scm_smob_apply_2_030; break;
 441     case SCM_GSUBR_MAKTYPE (0, 0, 1):
 442       apply_2 = scm_smob_apply_2_001; break;
 443     case SCM_GSUBR_MAKTYPE (1, 0, 1):
 444     case SCM_GSUBR_MAKTYPE (0, 1, 1):
 445       apply_2 = scm_smob_apply_2_011; break;
 446     case SCM_GSUBR_MAKTYPE (2, 0, 1):
 447     case SCM_GSUBR_MAKTYPE (1, 1, 1):
 448     case SCM_GSUBR_MAKTYPE (0, 2, 1):
 449       apply_2 = scm_smob_apply_2_021; break;
 450     default:
 451       apply_2 = scm_smob_apply_2_error; break;
 452     }
 453
 454   switch (type)
 455     {
 456     case SCM_GSUBR_MAKTYPE (3, 0, 0):
 457     case SCM_GSUBR_MAKTYPE (2, 1, 0):
 458     case SCM_GSUBR_MAKTYPE (1, 2, 0):
 459     case SCM_GSUBR_MAKTYPE (0, 3, 0):
 460       apply_3 = scm_smob_apply_3_030; break;
 461     case SCM_GSUBR_MAKTYPE (0, 0, 1):
 462       apply_3 = scm_smob_apply_3_001; break;
 463     case SCM_GSUBR_MAKTYPE (1, 0, 1):
 464     case SCM_GSUBR_MAKTYPE (0, 1, 1):
 465       apply_3 = scm_smob_apply_3_011; break;
 466     case SCM_GSUBR_MAKTYPE (2, 0, 1):
 467     case SCM_GSUBR_MAKTYPE (1, 1, 1):
 468     case SCM_GSUBR_MAKTYPE (0, 2, 1):
 469       apply_3 = scm_smob_apply_3_021; break;
 470     default:
 471       apply_3 = scm_smob_apply_3_error; break;
 472     }
 473
 474   scm_smobs[SCM_TC2SMOBNUM (tc)].apply = apply;
 475   scm_smobs[SCM_TC2SMOBNUM (tc)].apply_0 = apply_0;
 476   scm_smobs[SCM_TC2SMOBNUM (tc)].apply_1 = apply_1;
 477   scm_smobs[SCM_TC2SMOBNUM (tc)].apply_2 = apply_2;
 478   scm_smobs[SCM_TC2SMOBNUM (tc)].apply_3 = apply_3;
 479   scm_smobs[SCM_TC2SMOBNUM (tc)].gsubr_type = type;
 480 }
 481
 482 void
 483 scm_set_smob_mfpe (long tc,
 484                    SCM (*mark) (SCM),
 485                    scm_sizet (*free) (SCM),
 486                    int (*print) (SCM, SCM, scm_print_state *),
 487                    SCM (*equalp) (SCM, SCM))
 488 {
 489   if (mark) scm_set_smob_mark (tc, mark);
 490   if (free) scm_set_smob_free (tc, free);
 491   if (print) scm_set_smob_print (tc, print);
 492   if (equalp) scm_set_smob_equalp (tc, equalp);
 493 }
 494
 495
 496 SCM
 497 scm_make_smob (long tc)
 498 {
 499   int n = SCM_TC2SMOBNUM (tc);
 500   scm_sizet size = scm_smobs[n].size;
 501   SCM z;
 502   SCM_NEWCELL (z);
 503   if (size != 0)
 504     {
 505 #if 0
 506       SCM_ASSERT (scm_smobs[n].mark == 0,
 507                   0,
 508                   "forbidden operation for smobs with GC data, use SCM_NEWSMOB",
 509                   SCM_SMOBNAME (n));
 510 #endif
 511       SCM_SET_SMOB_DATA (z, scm_must_malloc (size, SCM_SMOBNAME (n)));
 512     }
 513   SCM_SET_CELL_TYPE (z, tc);
 514   return z;
 515 }
 516
 517 \f
 518 /* {Initialization for i/o types, float, bignum, the type of free cells}
 519  */
 520
 521 static int
 522 freeprint (SCM exp,
 523            SCM port,
 524            scm_print_state *pstate)
 525 {
 526   char buf[100];
 527
 528   sprintf (buf, "#<freed cell %p; GC missed a reference>", (void *) SCM_UNPACK (exp));
 529   scm_puts (buf, port);
 530
 531   return 1;
 532 }
 533
 534
 535 void
 536 scm_smob_prehistory ()
 537 {
 538   scm_numsmob = 0;
 539   scm_smobs = ((scm_smob_descriptor *)
 540                malloc (7 * sizeof (scm_smob_descriptor)));
 541
 542   /* WARNING: These scm_make_smob_type calls must be done in this order */
 543   scm_make_smob_type_mfpe ("free", 0,
 544                           NULL, NULL, freeprint, NULL);
 545
 546   scm_make_smob_type_mfpe ("big", 0,     /* freed in gc */
 547                           NULL, NULL, scm_bigprint, scm_bigequal);
 548
 549   scm_make_smob_type_mfpe ("real", 0,    /* freed in gc */
 550                            NULL, NULL, scm_print_real, scm_real_equalp);
 551
 552   scm_make_smob_type_mfpe ("complex", 0,    /* freed in gc */
 553                            NULL, NULL, scm_print_complex, scm_complex_equalp);
 554 }
 555
 556 /*
 557   Local Variables:
 558   c-file-style: "gnu"
 559   End:
 560 */