data.c 64.2 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Primitive operations on Lisp data types for GNU Emacs Lisp interpreter.
Karl Heuer's avatar
Karl Heuer committed
2
   Copyright (C) 1985, 1986, 1988, 1993, 1994 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include <signal.h>

23
#include <config.h>
Jim Blandy's avatar
Jim Blandy committed
24
#include "lisp.h"
Jim Blandy's avatar
Jim Blandy committed
25
#include "puresize.h"
Jim Blandy's avatar
Jim Blandy committed
26 27 28 29 30

#ifndef standalone
#include "buffer.h"
#endif

Jim Blandy's avatar
Jim Blandy committed
31
#include "syssignal.h"
Jim Blandy's avatar
Jim Blandy committed
32

33
#ifdef MSDOS
Karl Heuer's avatar
Karl Heuer committed
34
/* These are redefined (correctly, but differently) in values.h.  */
35 36 37 38 39
#undef INTBITS
#undef LONGBITS
#undef SHORTBITS
#endif

Jim Blandy's avatar
Jim Blandy committed
40
#ifdef LISP_FLOAT_TYPE
41

42 43 44
#ifdef STDC_HEADERS
#include <stdlib.h>
#endif
45 46 47 48 49 50 51 52 53 54 55

/* Work around a problem that happens because math.h on hpux 7
   defines two static variables--which, in Emacs, are not really static,
   because `static' is defined as nothing.  The problem is that they are
   here, in floatfns.c, and in lread.c.
   These macros prevent the name conflict.  */
#if defined (HPUX) && !defined (HPUX8)
#define _MAXLDBL data_c_maxldbl
#define _NMAXLDBL data_c_nmaxldbl
#endif

Jim Blandy's avatar
Jim Blandy committed
56 57 58
#include <math.h>
#endif /* LISP_FLOAT_TYPE */

59 60 61 62
#if !defined (atof)
extern double atof ();
#endif /* !atof */

Jim Blandy's avatar
Jim Blandy committed
63 64 65
Lisp_Object Qnil, Qt, Qquote, Qlambda, Qsubr, Qunbound;
Lisp_Object Qerror_conditions, Qerror_message, Qtop_level;
Lisp_Object Qerror, Qquit, Qwrong_type_argument, Qargs_out_of_range;
Jim Blandy's avatar
Jim Blandy committed
66
Lisp_Object Qvoid_variable, Qvoid_function, Qcyclic_function_indirection;
Jim Blandy's avatar
Jim Blandy committed
67 68
Lisp_Object Qsetting_constant, Qinvalid_read_syntax;
Lisp_Object Qinvalid_function, Qwrong_number_of_arguments, Qno_catch;
Roland McGrath's avatar
Roland McGrath committed
69
Lisp_Object Qend_of_file, Qarith_error, Qmark_inactive;
Jim Blandy's avatar
Jim Blandy committed
70
Lisp_Object Qbeginning_of_buffer, Qend_of_buffer, Qbuffer_read_only;
71
Lisp_Object Qintegerp, Qnatnump, Qwholenump, Qsymbolp, Qlistp, Qconsp;
Jim Blandy's avatar
Jim Blandy committed
72 73
Lisp_Object Qstringp, Qarrayp, Qsequencep, Qbufferp;
Lisp_Object Qchar_or_string_p, Qmarkerp, Qinteger_or_marker_p, Qvectorp;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
74
Lisp_Object Qbuffer_or_string_p;
Jim Blandy's avatar
Jim Blandy committed
75 76
Lisp_Object Qboundp, Qfboundp;
Lisp_Object Qcdr;
77
Lisp_Object Qad_advice_info, Qad_activate;
Jim Blandy's avatar
Jim Blandy committed
78

79 80 81
Lisp_Object Qrange_error, Qdomain_error, Qsingularity_error;
Lisp_Object Qoverflow_error, Qunderflow_error;

Jim Blandy's avatar
Jim Blandy committed
82
#ifdef LISP_FLOAT_TYPE
83
Lisp_Object Qfloatp;
Jim Blandy's avatar
Jim Blandy committed
84 85 86 87 88 89 90 91 92 93 94 95 96 97
Lisp_Object Qnumberp, Qnumber_or_marker_p;
#endif

static Lisp_Object swap_in_symval_forwarding ();

Lisp_Object
wrong_type_argument (predicate, value)
     register Lisp_Object predicate, value;
{
  register Lisp_Object tem;
  do
    {
      if (!EQ (Vmocklisp_arguments, Qt))
	{
98
	 if (STRINGP (value) &&
Jim Blandy's avatar
Jim Blandy committed
99
	     (EQ (predicate, Qintegerp) || EQ (predicate, Qinteger_or_marker_p)))
100
	   return Fstring_to_number (value);
101
	 if (INTEGERP (value) && EQ (predicate, Qstringp))
102
	   return Fnumber_to_string (value);
Jim Blandy's avatar
Jim Blandy committed
103
	}
104 105 106

      /* If VALUE is not even a valid Lisp object, abort here
	 where we can get a backtrace showing where it came from.  */
107
      if ((unsigned int) XGCTYPE (value) >= Lisp_Type_Limit)
108 109
	abort ();

Jim Blandy's avatar
Jim Blandy committed
110 111 112
      value = Fsignal (Qwrong_type_argument, Fcons (predicate, Fcons (value, Qnil)));
      tem = call1 (predicate, value);
    }
Jim Blandy's avatar
Jim Blandy committed
113
  while (NILP (tem));
Jim Blandy's avatar
Jim Blandy committed
114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142
  return value;
}

pure_write_error ()
{
  error ("Attempt to modify read-only object");
}

void
args_out_of_range (a1, a2)
     Lisp_Object a1, a2;
{
  while (1)
    Fsignal (Qargs_out_of_range, Fcons (a1, Fcons (a2, Qnil)));
}

void
args_out_of_range_3 (a1, a2, a3)
     Lisp_Object a1, a2, a3;
{
  while (1)
    Fsignal (Qargs_out_of_range, Fcons (a1, Fcons (a2, Fcons (a3, Qnil))));
}

Lisp_Object
make_number (num)
     int num;
{
  register Lisp_Object val;
143
  XSETINT (val, num);
Jim Blandy's avatar
Jim Blandy committed
144 145 146 147 148 149 150 151 152 153 154 155
  return val;
}

/* On some machines, XINT needs a temporary location.
   Here it is, in case it is needed.  */

int sign_extend_temp;

/* On a few machines, XINT can only be done by calling this.  */

int
sign_extend_lisp_int (num)
156
     EMACS_INT num;
Jim Blandy's avatar
Jim Blandy committed
157
{
158 159
  if (num & (((EMACS_INT) 1) << (VALBITS - 1)))
    return num | (((EMACS_INT) (-1)) << VALBITS);
Jim Blandy's avatar
Jim Blandy committed
160
  else
161
    return num & ((((EMACS_INT) 1) << VALBITS) - 1);
Jim Blandy's avatar
Jim Blandy committed
162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179
}

/* Data type predicates */

DEFUN ("eq", Feq, Seq, 2, 2, 0,
  "T if the two args are the same Lisp object.")
  (obj1, obj2)
     Lisp_Object obj1, obj2;
{
  if (EQ (obj1, obj2))
    return Qt;
  return Qnil;
}

DEFUN ("null", Fnull, Snull, 1, 1, 0, "T if OBJECT is nil.")
  (obj)
     Lisp_Object obj;
{
Jim Blandy's avatar
Jim Blandy committed
180
  if (NILP (obj))
Jim Blandy's avatar
Jim Blandy committed
181 182 183 184 185 186 187 188
    return Qt;
  return Qnil;
}

DEFUN ("consp", Fconsp, Sconsp, 1, 1, 0, "T if OBJECT is a cons cell.")
  (obj)
     Lisp_Object obj;
{
189
  if (CONSP (obj))
Jim Blandy's avatar
Jim Blandy committed
190 191 192 193 194 195 196 197
    return Qt;
  return Qnil;
}

DEFUN ("atom", Fatom, Satom, 1, 1, 0, "T if OBJECT is not a cons cell.  This includes nil.")
  (obj)
     Lisp_Object obj;
{
198
  if (CONSP (obj))
Jim Blandy's avatar
Jim Blandy committed
199 200 201 202 203 204 205 206
    return Qnil;
  return Qt;
}

DEFUN ("listp", Flistp, Slistp, 1, 1, 0, "T if OBJECT is a list.  This includes nil.")
  (obj)
     Lisp_Object obj;
{
207
  if (CONSP (obj) || NILP (obj))
Jim Blandy's avatar
Jim Blandy committed
208 209 210 211 212 213 214 215
    return Qt;
  return Qnil;
}

DEFUN ("nlistp", Fnlistp, Snlistp, 1, 1, 0, "T if OBJECT is not a list.  Lists include nil.")
  (obj)
     Lisp_Object obj;
{
216
  if (CONSP (obj) || NILP (obj))
Jim Blandy's avatar
Jim Blandy committed
217 218 219 220 221 222 223 224
    return Qnil;
  return Qt;
}

DEFUN ("symbolp", Fsymbolp, Ssymbolp, 1, 1, 0, "T if OBJECT is a symbol.")
  (obj)
     Lisp_Object obj;
{
225
  if (SYMBOLP (obj))
Jim Blandy's avatar
Jim Blandy committed
226 227 228 229 230 231 232 233
    return Qt;
  return Qnil;
}

DEFUN ("vectorp", Fvectorp, Svectorp, 1, 1, 0, "T if OBJECT is a vector.")
  (obj)
     Lisp_Object obj;
{
234
  if (VECTORP (obj))
Jim Blandy's avatar
Jim Blandy committed
235 236 237 238 239 240 241 242
    return Qt;
  return Qnil;
}

DEFUN ("stringp", Fstringp, Sstringp, 1, 1, 0, "T if OBJECT is a string.")
  (obj)
     Lisp_Object obj;
{
243
  if (STRINGP (obj))
Jim Blandy's avatar
Jim Blandy committed
244 245 246 247 248 249 250 251
    return Qt;
  return Qnil;
}

DEFUN ("arrayp", Farrayp, Sarrayp, 1, 1, 0, "T if OBJECT is an array (string or vector).")
  (obj)
     Lisp_Object obj;
{
252
  if (VECTORP (obj) || STRINGP (obj))
Jim Blandy's avatar
Jim Blandy committed
253 254 255 256 257 258 259 260 261
    return Qt;
  return Qnil;
}

DEFUN ("sequencep", Fsequencep, Ssequencep, 1, 1, 0,
  "T if OBJECT is a sequence (list or array).")
  (obj)
     register Lisp_Object obj;
{
262
  if (CONSP (obj) || NILP (obj) || VECTORP (obj) || STRINGP (obj))
Jim Blandy's avatar
Jim Blandy committed
263 264 265 266 267 268 269 270
    return Qt;
  return Qnil;
}

DEFUN ("bufferp", Fbufferp, Sbufferp, 1, 1, 0, "T if OBJECT is an editor buffer.")
  (obj)
     Lisp_Object obj;
{
271
  if (BUFFERP (obj))
Jim Blandy's avatar
Jim Blandy committed
272 273 274 275 276 277 278 279
    return Qt;
  return Qnil;
}

DEFUN ("markerp", Fmarkerp, Smarkerp, 1, 1, 0, "T if OBJECT is a marker (editor pointer).")
  (obj)
     Lisp_Object obj;
{
280
  if (MARKERP (obj))
Jim Blandy's avatar
Jim Blandy committed
281 282 283 284 285 286 287 288
    return Qt;
  return Qnil;
}

DEFUN ("subrp", Fsubrp, Ssubrp, 1, 1, 0, "T if OBJECT is a built-in function.")
  (obj)
     Lisp_Object obj;
{
289
  if (SUBRP (obj))
Jim Blandy's avatar
Jim Blandy committed
290 291 292 293
    return Qt;
  return Qnil;
}

Jim Blandy's avatar
Jim Blandy committed
294 295
DEFUN ("byte-code-function-p", Fbyte_code_function_p, Sbyte_code_function_p,
       1, 1, 0, "T if OBJECT is a byte-compiled function object.")
Jim Blandy's avatar
Jim Blandy committed
296 297 298
  (obj)
     Lisp_Object obj;
{
299
  if (COMPILEDP (obj))
Jim Blandy's avatar
Jim Blandy committed
300 301 302 303
    return Qt;
  return Qnil;
}

304 305
DEFUN ("char-or-string-p", Fchar_or_string_p, Schar_or_string_p, 1, 1, 0,
  "T if OBJECT is a character (an integer) or a string.")
Jim Blandy's avatar
Jim Blandy committed
306 307 308
  (obj)
     register Lisp_Object obj;
{
309
  if (INTEGERP (obj) || STRINGP (obj))
Jim Blandy's avatar
Jim Blandy committed
310 311 312 313
    return Qt;
  return Qnil;
}

314
DEFUN ("integerp", Fintegerp, Sintegerp, 1, 1, 0, "T if OBJECT is an integer.")
Jim Blandy's avatar
Jim Blandy committed
315 316 317
  (obj)
     Lisp_Object obj;
{
318
  if (INTEGERP (obj))
Jim Blandy's avatar
Jim Blandy committed
319 320 321 322
    return Qt;
  return Qnil;
}

323 324
DEFUN ("integer-or-marker-p", Finteger_or_marker_p, Sinteger_or_marker_p, 1, 1, 0,
  "T if OBJECT is an integer or a marker (editor pointer).")
Jim Blandy's avatar
Jim Blandy committed
325
  (obj)
326
     register Lisp_Object obj;
Jim Blandy's avatar
Jim Blandy committed
327
{
328
  if (MARKERP (obj) || INTEGERP (obj))
Jim Blandy's avatar
Jim Blandy committed
329 330 331 332
    return Qt;
  return Qnil;
}

333 334
DEFUN ("natnump", Fnatnump, Snatnump, 1, 1, 0,
  "T if OBJECT is a nonnegative integer.")
Jim Blandy's avatar
Jim Blandy committed
335 336 337
  (obj)
     Lisp_Object obj;
{
338
  if (NATNUMP (obj))
Jim Blandy's avatar
Jim Blandy committed
339 340 341 342 343 344 345 346 347
    return Qt;
  return Qnil;
}

DEFUN ("numberp", Fnumberp, Snumberp, 1, 1, 0,
       "T if OBJECT is a number (floating point or integer).")
  (obj)
     Lisp_Object obj;
{
Jim Blandy's avatar
Jim Blandy committed
348
  if (NUMBERP (obj))
Jim Blandy's avatar
Jim Blandy committed
349
    return Qt;
Jim Blandy's avatar
Jim Blandy committed
350 351
  else
    return Qnil;
Jim Blandy's avatar
Jim Blandy committed
352 353 354 355 356 357 358 359
}

DEFUN ("number-or-marker-p", Fnumber_or_marker_p,
       Snumber_or_marker_p, 1, 1, 0,
       "T if OBJECT is a number or a marker.")
  (obj)
     Lisp_Object obj;
{
360
  if (NUMBERP (obj) || MARKERP (obj))
Jim Blandy's avatar
Jim Blandy committed
361 362 363
    return Qt;
  return Qnil;
}
364 365 366 367 368 369 370

#ifdef LISP_FLOAT_TYPE
DEFUN ("floatp", Ffloatp, Sfloatp, 1, 1, 0,
       "T if OBJECT is a floating point number.")
  (obj)
     Lisp_Object obj;
{
371
  if (FLOATP (obj))
372 373 374
    return Qt;
  return Qnil;
}
Jim Blandy's avatar
Jim Blandy committed
375 376 377 378 379 380 381 382 383 384 385 386
#endif /* LISP_FLOAT_TYPE */

/* Extract and set components of lists */

DEFUN ("car", Fcar, Scar, 1, 1, 0,
  "Return the car of CONSCELL.  If arg is nil, return nil.\n\
Error if arg is not nil and not a cons cell.  See also `car-safe'.")
  (list)
     register Lisp_Object list;
{
  while (1)
    {
387
      if (CONSP (list))
Jim Blandy's avatar
Jim Blandy committed
388 389 390 391 392 393 394 395 396 397 398 399 400
	return XCONS (list)->car;
      else if (EQ (list, Qnil))
	return Qnil;
      else
	list = wrong_type_argument (Qlistp, list);
    }
}

DEFUN ("car-safe", Fcar_safe, Scar_safe, 1, 1, 0,
  "Return the car of OBJECT if it is a cons cell, or else nil.")
  (object)
     Lisp_Object object;
{
401
  if (CONSP (object))
Jim Blandy's avatar
Jim Blandy committed
402 403 404 405 406 407 408 409 410 411 412 413 414 415
    return XCONS (object)->car;
  else
    return Qnil;
}

DEFUN ("cdr", Fcdr, Scdr, 1, 1, 0,
  "Return the cdr of CONSCELL.  If arg is nil, return nil.\n\
Error if arg is not nil and not a cons cell.  See also `cdr-safe'.")

  (list)
     register Lisp_Object list;
{
  while (1)
    {
416
      if (CONSP (list))
Jim Blandy's avatar
Jim Blandy committed
417 418 419 420 421 422 423 424 425
	return XCONS (list)->cdr;
      else if (EQ (list, Qnil))
	return Qnil;
      else
	list = wrong_type_argument (Qlistp, list);
    }
}

DEFUN ("cdr-safe", Fcdr_safe, Scdr_safe, 1, 1, 0,
426
  "Return the cdr of OBJECT if it is a cons cell, or else nil.")
Jim Blandy's avatar
Jim Blandy committed
427 428 429
  (object)
     Lisp_Object object;
{
430
  if (CONSP (object))
Jim Blandy's avatar
Jim Blandy committed
431 432 433 434 435 436 437 438 439 440
    return XCONS (object)->cdr;
  else
    return Qnil;
}

DEFUN ("setcar", Fsetcar, Ssetcar, 2, 2, 0,
  "Set the car of CONSCELL to be NEWCAR.  Returns NEWCAR.")
  (cell, newcar)
     register Lisp_Object cell, newcar;
{
441
  if (!CONSP (cell))
Jim Blandy's avatar
Jim Blandy committed
442 443 444 445 446 447 448 449 450 451 452 453
    cell = wrong_type_argument (Qconsp, cell);

  CHECK_IMPURE (cell);
  XCONS (cell)->car = newcar;
  return newcar;
}

DEFUN ("setcdr", Fsetcdr, Ssetcdr, 2, 2, 0,
  "Set the cdr of CONSCELL to be NEWCDR.  Returns NEWCDR.")
  (cell, newcdr)
     register Lisp_Object cell, newcdr;
{
454
  if (!CONSP (cell))
Jim Blandy's avatar
Jim Blandy committed
455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472
    cell = wrong_type_argument (Qconsp, cell);

  CHECK_IMPURE (cell);
  XCONS (cell)->cdr = newcdr;
  return newcdr;
}

/* Extract and set components of symbols */

DEFUN ("boundp", Fboundp, Sboundp, 1, 1, 0, "T if SYMBOL's value is not void.")
  (sym)
     register Lisp_Object sym;
{
  Lisp_Object valcontents;
  CHECK_SYMBOL (sym, 0);

  valcontents = XSYMBOL (sym)->value;

Karl Heuer's avatar
Karl Heuer committed
473 474
  if (BUFFER_LOCAL_VALUEP (valcontents)
      || SOME_BUFFER_LOCAL_VALUEP (valcontents))
475
    valcontents = swap_in_symval_forwarding (sym, valcontents);
Jim Blandy's avatar
Jim Blandy committed
476

477
  return (EQ (valcontents, Qunbound) ? Qnil : Qt);
Jim Blandy's avatar
Jim Blandy committed
478 479 480 481 482 483 484
}

DEFUN ("fboundp", Ffboundp, Sfboundp, 1, 1, 0, "T if SYMBOL's function definition is not void.")
  (sym)
     register Lisp_Object sym;
{
  CHECK_SYMBOL (sym, 0);
485
  return (EQ (XSYMBOL (sym)->function, Qunbound) ? Qnil : Qt);
Jim Blandy's avatar
Jim Blandy committed
486 487 488 489 490 491 492
}

DEFUN ("makunbound", Fmakunbound, Smakunbound, 1, 1, 0, "Make SYMBOL's value be void.")
  (sym)
     register Lisp_Object sym;
{
  CHECK_SYMBOL (sym, 0);
Jim Blandy's avatar
Jim Blandy committed
493
  if (NILP (sym) || EQ (sym, Qt))
Jim Blandy's avatar
Jim Blandy committed
494 495 496 497 498 499 500 501 502 503
    return Fsignal (Qsetting_constant, Fcons (sym, Qnil));
  Fset (sym, Qunbound);
  return sym;
}

DEFUN ("fmakunbound", Ffmakunbound, Sfmakunbound, 1, 1, 0, "Make SYMBOL's function definition be void.")
  (sym)
     register Lisp_Object sym;
{
  CHECK_SYMBOL (sym, 0);
504 505
  if (NILP (sym) || EQ (sym, Qt))
    return Fsignal (Qsetting_constant, Fcons (sym, Qnil));
Jim Blandy's avatar
Jim Blandy committed
506 507 508 509 510 511
  XSYMBOL (sym)->function = Qunbound;
  return sym;
}

DEFUN ("symbol-function", Fsymbol_function, Ssymbol_function, 1, 1, 0,
  "Return SYMBOL's function definition.  Error if that is void.")
Jim Blandy's avatar
Jim Blandy committed
512 513
  (symbol)
     register Lisp_Object symbol;
Jim Blandy's avatar
Jim Blandy committed
514
{
Jim Blandy's avatar
Jim Blandy committed
515 516 517 518
  CHECK_SYMBOL (symbol, 0);
  if (EQ (XSYMBOL (symbol)->function, Qunbound))
    return Fsignal (Qvoid_function, Fcons (symbol, Qnil));
  return XSYMBOL (symbol)->function;
Jim Blandy's avatar
Jim Blandy committed
519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535
}

DEFUN ("symbol-plist", Fsymbol_plist, Ssymbol_plist, 1, 1, 0, "Return SYMBOL's property list.")
  (sym)
     register Lisp_Object sym;
{
  CHECK_SYMBOL (sym, 0);
  return XSYMBOL (sym)->plist;
}

DEFUN ("symbol-name", Fsymbol_name, Ssymbol_name, 1, 1, 0, "Return SYMBOL's name, a string.")
  (sym)
     register Lisp_Object sym;
{
  register Lisp_Object name;

  CHECK_SYMBOL (sym, 0);
536
  XSETSTRING (name, XSYMBOL (sym)->name);
Jim Blandy's avatar
Jim Blandy committed
537 538 539 540 541 542 543 544 545
  return name;
}

DEFUN ("fset", Ffset, Sfset, 2, 2, 0,
  "Set SYMBOL's function definition to NEWVAL, and return NEWVAL.")
  (sym, newdef)
     register Lisp_Object sym, newdef;
{
  CHECK_SYMBOL (sym, 0);
546 547
  if (NILP (sym) || EQ (sym, Qt))
    return Fsignal (Qsetting_constant, Fcons (sym, Qnil));
Jim Blandy's avatar
Jim Blandy committed
548
  if (!NILP (Vautoload_queue) && !EQ (XSYMBOL (sym)->function, Qunbound))
Jim Blandy's avatar
Jim Blandy committed
549 550 551
    Vautoload_queue = Fcons (Fcons (sym, XSYMBOL (sym)->function),
			     Vautoload_queue);
  XSYMBOL (sym)->function = newdef;
552
  /* Handle automatic advice activation */
553
  if (CONSP (XSYMBOL (sym)->plist) && !NILP (Fget (sym, Qad_advice_info)))
554
    {
555
      call2 (Qad_activate, sym, Qnil);
556 557
      newdef = XSYMBOL (sym)->function;
    }
Jim Blandy's avatar
Jim Blandy committed
558 559 560
  return newdef;
}

561 562
/* This name should be removed once it is eliminated from elsewhere.  */

563
DEFUN ("defalias", Fdefalias, Sdefalias, 2, 2, 0,
564 565 566 567 568 569 570 571 572 573
  "Set SYMBOL's function definition to NEWVAL, and return NEWVAL.\n\
Associates the function with the current load file, if any.")
  (sym, newdef)
     register Lisp_Object sym, newdef;
{
  CHECK_SYMBOL (sym, 0);
  if (!NILP (Vautoload_queue) && !EQ (XSYMBOL (sym)->function, Qunbound))
    Vautoload_queue = Fcons (Fcons (sym, XSYMBOL (sym)->function),
			     Vautoload_queue);
  XSYMBOL (sym)->function = newdef;
574 575 576 577 578 579
  /* Handle automatic advice activation */
  if (CONSP (XSYMBOL (sym)->plist) && !NILP (Fget (sym, Qad_advice_info)))
    {
      call2 (Qad_activate, sym, Qnil);
      newdef = XSYMBOL (sym)->function;
    }
580 581 582 583
  LOADHIST_ATTACH (sym);
  return newdef;
}

584 585 586 587 588 589 590 591 592 593 594
DEFUN ("define-function", Fdefine_function, Sdefine_function, 2, 2, 0,
  "Set SYMBOL's function definition to NEWVAL, and return NEWVAL.\n\
Associates the function with the current load file, if any.")
  (sym, newdef)
     register Lisp_Object sym, newdef;
{
  CHECK_SYMBOL (sym, 0);
  if (!NILP (Vautoload_queue) && !EQ (XSYMBOL (sym)->function, Qunbound))
    Vautoload_queue = Fcons (Fcons (sym, XSYMBOL (sym)->function),
			     Vautoload_queue);
  XSYMBOL (sym)->function = newdef;
595 596 597 598 599 600
  /* Handle automatic advice activation */
  if (CONSP (XSYMBOL (sym)->plist) && !NILP (Fget (sym, Qad_advice_info)))
    {
      call2 (Qad_activate, sym, Qnil);
      newdef = XSYMBOL (sym)->function;
    }
601 602 603 604
  LOADHIST_ATTACH (sym);
  return newdef;
}

Jim Blandy's avatar
Jim Blandy committed
605 606 607 608 609 610 611 612 613
DEFUN ("setplist", Fsetplist, Ssetplist, 2, 2, 0,
  "Set SYMBOL's property list to NEWVAL, and return NEWVAL.")
  (sym, newplist)
     register Lisp_Object sym, newplist;
{
  CHECK_SYMBOL (sym, 0);
  XSYMBOL (sym)->plist = newplist;
  return newplist;
}
Jim Blandy's avatar
Jim Blandy committed
614

Jim Blandy's avatar
Jim Blandy committed
615 616 617 618 619 620 621 622 623 624 625 626 627

/* Getting and setting values of symbols */

/* Given the raw contents of a symbol value cell,
   return the Lisp value of the symbol.
   This does not handle buffer-local variables; use
   swap_in_symval_forwarding for that.  */

Lisp_Object
do_symval_forwarding (valcontents)
     register Lisp_Object valcontents;
{
  register Lisp_Object val;
628 629 630 631 632 633 634
  int offset;
  if (MISCP (valcontents))
    switch (XMISC (valcontents)->type)
      {
      case Lisp_Misc_Intfwd:
	XSETINT (val, *XINTFWD (valcontents)->intvar);
	return val;
Jim Blandy's avatar
Jim Blandy committed
635

636 637
      case Lisp_Misc_Boolfwd:
	return (*XBOOLFWD (valcontents)->boolvar ? Qt : Qnil);
Jim Blandy's avatar
Jim Blandy committed
638

639 640
      case Lisp_Misc_Objfwd:
	return *XOBJFWD (valcontents)->objvar;
Jim Blandy's avatar
Jim Blandy committed
641

642 643 644 645
      case Lisp_Misc_Buffer_Objfwd:
	offset = XBUFFER_OBJFWD (valcontents)->offset;
	return *(Lisp_Object *)(offset + (char *)current_buffer);
      }
Jim Blandy's avatar
Jim Blandy committed
646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664
  return valcontents;
}

/* Store NEWVAL into SYM, where VALCONTENTS is found in the value cell
   of SYM.  If SYM is buffer-local, VALCONTENTS should be the
   buffer-independent contents of the value cell: forwarded just one
   step past the buffer-localness.  */

void
store_symval_forwarding (sym, valcontents, newval)
     Lisp_Object sym;
     register Lisp_Object valcontents, newval;
{
#ifdef SWITCH_ENUM_BUG
  switch ((int) XTYPE (valcontents))
#else
  switch (XTYPE (valcontents))
#endif
    {
665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696
    case Lisp_Misc:
      switch (XMISC (valcontents)->type)
	{
	case Lisp_Misc_Intfwd:
	  CHECK_NUMBER (newval, 1);
	  *XINTFWD (valcontents)->intvar = XINT (newval);
	  break;

	case Lisp_Misc_Boolfwd:
	  *XBOOLFWD (valcontents)->boolvar = NILP (newval) ? 0 : 1;
	  break;

	case Lisp_Misc_Objfwd:
	  *XOBJFWD (valcontents)->objvar = newval;
	  break;

	case Lisp_Misc_Buffer_Objfwd:
	  {
	    int offset = XBUFFER_OBJFWD (valcontents)->offset;
	    Lisp_Object type;

	    type = *(Lisp_Object *)(offset + (char *)&buffer_local_types);
	    if (! NILP (type) && ! NILP (newval)
		&& XTYPE (newval) != XINT (type))
	      buffer_slot_type_mismatch (offset);

	    *(Lisp_Object *)(offset + (char *)current_buffer) = newval;
	    break;
	  }
	default:
	  goto def;
	}
Jim Blandy's avatar
Jim Blandy committed
697 698 699
      break;

    default:
700
    def:
Jim Blandy's avatar
Jim Blandy committed
701
      valcontents = XSYMBOL (sym)->value;
702 703
      if (BUFFER_LOCAL_VALUEP (valcontents)
	  || SOME_BUFFER_LOCAL_VALUEP (valcontents))
704
	XBUFFER_LOCAL_VALUE (valcontents)->car = newval;
Jim Blandy's avatar
Jim Blandy committed
705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721
      else
	XSYMBOL (sym)->value = newval;
    }
}

/* Set up the buffer-local symbol SYM for validity in the current
   buffer.  VALCONTENTS is the contents of its value cell.
   Return the value forwarded one step past the buffer-local indicator.  */

static Lisp_Object
swap_in_symval_forwarding (sym, valcontents)
     Lisp_Object sym, valcontents;
{
  /* valcontents is a list
     (REALVALUE BUFFER CURRENT-ALIST-ELEMENT . DEFAULT-VALUE)).
     
     CURRENT-ALIST-ELEMENT is a pointer to an element of BUFFER's
722 723 724 725 726 727 728 729 730 731 732
     local_var_alist, that being the element whose car is this
     variable.  Or it can be a pointer to the
     (CURRENT-ALIST-ELEMENT . DEFAULT-VALUE), if BUFFER does not have
     an element in its alist for this variable.

     If the current buffer is not BUFFER, we store the current
     REALVALUE value into CURRENT-ALIST-ELEMENT, then find the
     appropriate alist element for the buffer now current and set up
     CURRENT-ALIST-ELEMENT.  Then we set REALVALUE out of that
     element, and store into BUFFER.

Jim Blandy's avatar
Jim Blandy committed
733 734 735
     Note that REALVALUE can be a forwarding pointer. */

  register Lisp_Object tem1;
736
  tem1 = XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->car;
Jim Blandy's avatar
Jim Blandy committed
737

Jim Blandy's avatar
Jim Blandy committed
738
  if (NILP (tem1) || current_buffer != XBUFFER (tem1))
Jim Blandy's avatar
Jim Blandy committed
739
    {
740 741 742
      tem1 = XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car;
      Fsetcdr (tem1,
	       do_symval_forwarding (XBUFFER_LOCAL_VALUE (valcontents)->car));
Jim Blandy's avatar
Jim Blandy committed
743
      tem1 = assq_no_quit (sym, current_buffer->local_var_alist);
Jim Blandy's avatar
Jim Blandy committed
744
      if (NILP (tem1))
745 746 747 748 749 750
	tem1 = XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr;
      XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car = tem1;
      XSETBUFFER (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->car,
		  current_buffer);
      store_symval_forwarding (sym, XBUFFER_LOCAL_VALUE (valcontents)->car,
			       Fcdr (tem1));
Jim Blandy's avatar
Jim Blandy committed
751
    }
752
  return XBUFFER_LOCAL_VALUE (valcontents)->car;
Jim Blandy's avatar
Jim Blandy committed
753 754
}

Jim Blandy's avatar
Jim Blandy committed
755 756 757 758 759
/* Find the value of a symbol, returning Qunbound if it's not bound.
   This is helpful for code which just wants to get a variable's value
   if it has one, without signalling an error.
   Note that it must not be possible to quit
   within this function.  Great care is required for this.  */
Jim Blandy's avatar
Jim Blandy committed
760

Jim Blandy's avatar
Jim Blandy committed
761 762
Lisp_Object
find_symbol_value (sym)
Jim Blandy's avatar
Jim Blandy committed
763 764 765 766 767 768 769
     Lisp_Object sym;
{
  register Lisp_Object valcontents, tem1;
  register Lisp_Object val;
  CHECK_SYMBOL (sym, 0);
  valcontents = XSYMBOL (sym)->value;

Karl Heuer's avatar
Karl Heuer committed
770 771
  if (BUFFER_LOCAL_VALUEP (valcontents)
      || SOME_BUFFER_LOCAL_VALUEP (valcontents))
772
    valcontents = swap_in_symval_forwarding (sym, valcontents);
Jim Blandy's avatar
Jim Blandy committed
773

774 775
  if (MISCP (valcontents))
    {
776 777 778 779 780
      switch (XMISC (valcontents)->type)
	{
	case Lisp_Misc_Intfwd:
	  XSETINT (val, *XINTFWD (valcontents)->intvar);
	  return val;
Jim Blandy's avatar
Jim Blandy committed
781

782 783
	case Lisp_Misc_Boolfwd:
	  return (*XBOOLFWD (valcontents)->boolvar ? Qt : Qnil);
Jim Blandy's avatar
Jim Blandy committed
784

785 786
	case Lisp_Misc_Objfwd:
	  return *XOBJFWD (valcontents)->objvar;
Jim Blandy's avatar
Jim Blandy committed
787

788 789 790 791
	case Lisp_Misc_Buffer_Objfwd:
	  return *(Lisp_Object *)(XBUFFER_OBJFWD (valcontents)->offset
				  + (char *)current_buffer);
	}
Jim Blandy's avatar
Jim Blandy committed
792 793 794 795 796
    }

  return valcontents;
}

Jim Blandy's avatar
Jim Blandy committed
797 798 799 800 801
DEFUN ("symbol-value", Fsymbol_value, Ssymbol_value, 1, 1, 0,
  "Return SYMBOL's value.  Error if that is void.")
  (sym)
     Lisp_Object sym;
{
802
  Lisp_Object val;
Jim Blandy's avatar
Jim Blandy committed
803

804
  val = find_symbol_value (sym);
Jim Blandy's avatar
Jim Blandy committed
805 806 807 808 809 810
  if (EQ (val, Qunbound))
    return Fsignal (Qvoid_variable, Fcons (sym, Qnil));
  else
    return val;
}

Jim Blandy's avatar
Jim Blandy committed
811 812 813 814 815
DEFUN ("set", Fset, Sset, 2, 2, 0,
  "Set SYMBOL's value to NEWVAL, and return NEWVAL.")
  (sym, newval)
     register Lisp_Object sym, newval;
{
816
  int voide = EQ (newval, Qunbound);
Jim Blandy's avatar
Jim Blandy committed
817 818 819 820

  register Lisp_Object valcontents, tem1, current_alist_element;

  CHECK_SYMBOL (sym, 0);
Jim Blandy's avatar
Jim Blandy committed
821
  if (NILP (sym) || EQ (sym, Qt))
Jim Blandy's avatar
Jim Blandy committed
822 823 824
    return Fsignal (Qsetting_constant, Fcons (sym, Qnil));
  valcontents = XSYMBOL (sym)->value;

825
  if (BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
826
    {
827
      register int idx = XBUFFER_OBJFWD (valcontents)->offset;
828 829
      register int mask = XINT (*((Lisp_Object *)
				  (idx + (char *)&buffer_local_flags)));
Jim Blandy's avatar
Jim Blandy committed
830 831 832 833
      if (mask > 0)
	current_buffer->local_var_flags |= mask;
    }

834 835
  else if (BUFFER_LOCAL_VALUEP (valcontents)
	   || SOME_BUFFER_LOCAL_VALUEP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
836
    {
837 838
      /* valcontents is actually a pointer to a struct resembling a cons,
	 with contents something like:
Jim Blandy's avatar
Jim Blandy committed
839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
	 (REALVALUE BUFFER CURRENT-ALIST-ELEMENT . DEFAULT-VALUE).

	 BUFFER is the last buffer for which this symbol's value was
	 made up to date.

	 CURRENT-ALIST-ELEMENT is a pointer to an element of BUFFER's
	 local_var_alist, that being the element whose car is this
	 variable.  Or it can be a pointer to the
	 (CURRENT-ALIST-ELEMENT . DEFAULT-VALUE), if BUFFER does not
	 have an element in its alist for this variable (that is, if
	 BUFFER sees the default value of this variable).

	 If we want to examine or set the value and BUFFER is current,
	 we just examine or set REALVALUE. If BUFFER is not current, we
	 store the current REALVALUE value into CURRENT-ALIST-ELEMENT,
	 then find the appropriate alist element for the buffer now
	 current and set up CURRENT-ALIST-ELEMENT.  Then we set
	 REALVALUE out of that element, and store into BUFFER.

	 If we are setting the variable and the current buffer does
	 not have an alist entry for this variable, an alist entry is
	 created.

	 Note that REALVALUE can be a forwarding pointer.  Each time
	 it is examined or set, forwarding must be done.  */

      /* What value are we caching right now?  */
      current_alist_element =
867
	XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car;
Jim Blandy's avatar
Jim Blandy committed
868 869 870 871 872 873

      /* If the current buffer is not the buffer whose binding is
	 currently cached, or if it's a Lisp_Buffer_Local_Value and
	 we're looking at the default value, the cache is invalid; we
	 need to write it out, and find the new CURRENT-ALIST-ELEMENT.  */
      if ((current_buffer
874
	   != XBUFFER (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->car))
875
	  || (BUFFER_LOCAL_VALUEP (valcontents)
876 877
	      && EQ (XCONS (current_alist_element)->car,
		     current_alist_element)))
Jim Blandy's avatar
Jim Blandy committed
878
	{
Jim Blandy's avatar
Jim Blandy committed
879 880 881 882
	  /* Write out the cached value for the old buffer; copy it
	     back to its alist element.  This works if the current
	     buffer only sees the default value, too.  */
          Fsetcdr (current_alist_element,
883
		   do_symval_forwarding (XBUFFER_LOCAL_VALUE (valcontents)->car));
Jim Blandy's avatar
Jim Blandy committed
884

Jim Blandy's avatar
Jim Blandy committed
885
	  /* Find the new value for CURRENT-ALIST-ELEMENT.  */
Jim Blandy's avatar
Jim Blandy committed
886
	  tem1 = Fassq (sym, current_buffer->local_var_alist);
Jim Blandy's avatar
Jim Blandy committed
887
	  if (NILP (tem1))
Jim Blandy's avatar
Jim Blandy committed
888 889 890 891 892 893
	    {
	      /* This buffer still sees the default value.  */

	      /* If the variable is a Lisp_Some_Buffer_Local_Value,
		 make CURRENT-ALIST-ELEMENT point to itself,
		 indicating that we're seeing the default value.  */
894
	      if (SOME_BUFFER_LOCAL_VALUEP (valcontents))
895
		tem1 = XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr;
Jim Blandy's avatar
Jim Blandy committed
896 897 898 899 900 901 902 903 904 905 906 907

	      /* If it's a Lisp_Buffer_Local_Value, give this buffer a
		 new assoc for a local value and set
		 CURRENT-ALIST-ELEMENT to point to that.  */
	      else
		{
		  tem1 = Fcons (sym, Fcdr (current_alist_element));
		  current_buffer->local_var_alist =
		    Fcons (tem1, current_buffer->local_var_alist);
		}
	    }
	  /* Cache the new buffer's assoc in CURRENT-ALIST-ELEMENT.  */
908 909
	  XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car
	    = tem1;
Jim Blandy's avatar
Jim Blandy committed
910 911

	  /* Set BUFFER, now that CURRENT-ALIST-ELEMENT is accurate.  */
912 913
	  XSETBUFFER (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->car,
		      current_buffer);
Jim Blandy's avatar
Jim Blandy committed
914
	}
915
      valcontents = XBUFFER_LOCAL_VALUE (valcontents)->car;
Jim Blandy's avatar
Jim Blandy committed
916
    }
Jim Blandy's avatar
Jim Blandy committed
917

Jim Blandy's avatar
Jim Blandy committed
918 919 920 921 922 923
  /* If storing void (making the symbol void), forward only through
     buffer-local indicator, not through Lisp_Objfwd, etc.  */
  if (voide)
    store_symval_forwarding (sym, Qnil, newval);
  else
    store_symval_forwarding (sym, valcontents, newval);
Jim Blandy's avatar
Jim Blandy committed
924

Jim Blandy's avatar
Jim Blandy committed
925 926 927 928 929 930
  return newval;
}

/* Access or set a buffer-local symbol's default value.  */

/* Return the default value of SYM, but don't check for voidness.
931
   Return Qunbound if it is void.  */
Jim Blandy's avatar
Jim Blandy committed
932 933 934 935 936 937 938 939 940 941 942 943

Lisp_Object
default_value (sym)
     Lisp_Object sym;
{
  register Lisp_Object valcontents;

  CHECK_SYMBOL (sym, 0);
  valcontents = XSYMBOL (sym)->value;

  /* For a built-in buffer-local variable, get the default value
     rather than letting do_symval_forwarding get the current value.  */
944
  if (BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
945
    {
946
      register int idx = XBUFFER_OBJFWD (valcontents)->offset;
Jim Blandy's avatar
Jim Blandy committed
947

948
      if (XINT (*(Lisp_Object *) (idx + (char *) &buffer_local_flags)) != 0)
Jim Blandy's avatar
Jim Blandy committed
949 950 951 952
	return *(Lisp_Object *)(idx + (char *) &buffer_defaults);
    }

  /* Handle user-created local variables.  */
953 954
  if (BUFFER_LOCAL_VALUEP (valcontents)
      || SOME_BUFFER_LOCAL_VALUEP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
955 956 957 958 959 960 961
    {
      /* If var is set up for a buffer that lacks a local value for it,
	 the current value is nominally the default value.
	 But the current value slot may be more up to date, since
	 ordinary setq stores just that slot.  So use that.  */
      Lisp_Object current_alist_element, alist_element_car;
      current_alist_element
962
	= XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car;
Jim Blandy's avatar
Jim Blandy committed
963 964
      alist_element_car = XCONS (current_alist_element)->car;
      if (EQ (alist_element_car, current_alist_element))
965
	return do_symval_forwarding (XBUFFER_LOCAL_VALUE (valcontents)->car);
Jim Blandy's avatar
Jim Blandy committed
966
      else
967
	return XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->cdr;
Jim Blandy's avatar
Jim Blandy committed
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982
    }
  /* For other variables, get the current value.  */
  return do_symval_forwarding (valcontents);
}

DEFUN ("default-boundp", Fdefault_boundp, Sdefault_boundp, 1, 1, 0,
  "Return T if SYMBOL has a non-void default value.\n\
This is the value that is seen in buffers that do not have their own values\n\
for this variable.")
  (sym)
     Lisp_Object sym;
{
  register Lisp_Object value;

  value = default_value (sym);
983
  return (EQ (value, Qunbound) ? Qnil : Qt);
Jim Blandy's avatar
Jim Blandy committed
984 985 986 987 988 989 990 991 992 993 994 995 996
}

DEFUN ("default-value", Fdefault_value, Sdefault_value, 1, 1, 0,
  "Return SYMBOL's default value.\n\
This is the value that is seen in buffers that do not have their own values\n\
for this variable.  The default value is meaningful for variables with\n\
local bindings in certain buffers.")
  (sym)
     Lisp_Object sym;
{
  register Lisp_Object value;

  value = default_value (sym);
997
  if (EQ (value, Qunbound))
Jim Blandy's avatar
Jim Blandy committed
998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016
    return Fsignal (Qvoid_variable, Fcons (sym, Qnil));
  return value;
}

DEFUN ("set-default", Fset_default, Sset_default, 2, 2, 0,
  "Set SYMBOL's default value to VAL.  SYMBOL and VAL are evaluated.\n\
The default value is seen in buffers that do not have their own values\n\
for this variable.")
  (sym, value)
     Lisp_Object sym, value;
{
  register Lisp_Object valcontents, current_alist_element, alist_element_buffer;

  CHECK_SYMBOL (sym, 0);
  valcontents = XSYMBOL (sym)->value;

  /* Handle variables like case-fold-search that have special slots
     in the buffer.  Make them work apparently like Lisp_Buffer_Local_Value
     variables.  */
1017
  if (BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1018
    {
1019
      register int idx = XBUFFER_OBJFWD (valcontents)->offset;
Jim Blandy's avatar
Jim Blandy committed
1020
      register struct buffer *b;
1021 1022
      register int mask = XINT (*((Lisp_Object *)
				  (idx + (char *)&buffer_local_flags)));
Jim Blandy's avatar
Jim Blandy committed
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033

      if (mask > 0)
	{
	  *(Lisp_Object *)(idx + (char *) &buffer_defaults) = value;
	  for (b = all_buffers; b; b = b->next)
	    if (!(b->local_var_flags & mask))
	      *(Lisp_Object *)(idx + (char *) b) = value;
	}
      return value;
    }

1034 1035
  if (!BUFFER_LOCAL_VALUEP (valcontents)
      && !SOME_BUFFER_LOCAL_VALUEP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1036 1037 1038
    return Fset (sym, value);

  /* Store new value into the DEFAULT-VALUE slot */
1039
  XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->cdr = value;
Jim Blandy's avatar
Jim Blandy committed
1040 1041

  /* If that slot is current, we must set the REALVALUE slot too */
1042 1043
  current_alist_element
    = XCONS (XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->cdr)->car;
Jim Blandy's avatar
Jim Blandy committed
1044 1045
  alist_element_buffer = Fcar (current_alist_element);
  if (EQ (alist_element_buffer, current_alist_element))
1046 1047
    store_symval_forwarding (sym, XBUFFER_LOCAL_VALUE (valcontents)->car,
			     value);
Jim Blandy's avatar
Jim Blandy committed
1048 1049 1050 1051 1052

  return value;
}

DEFUN ("setq-default", Fsetq_default, Ssetq_default, 2, UNEVALLED, 0,
1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063
       "Set the default value of variable VAR to VALUE.\n\
VAR, the variable name, is literal (not evaluated);\n\
VALUE is an expression and it is evaluated.\n\
The default value of a variable is seen in buffers\n\
that do not have their own values for the variable.\n\
\n\
More generally, you can use multiple variables and values, as in\n\
  (setq-default SYM VALUE SYM VALUE...)\n\
This sets each SYM's default value to the corresponding VALUE.\n\
The VALUE for the Nth SYM can refer to the new default values\n\
of previous SYMs.")
Jim Blandy's avatar
Jim Blandy committed
1064 1065 1066 1067 1068 1069 1070
  (args)
     Lisp_Object args;
{
  register Lisp_Object args_left;
  register Lisp_Object val, sym;
  struct gcpro gcpro1;

Jim Blandy's avatar
Jim Blandy committed
1071
  if (NILP (args))
Jim Blandy's avatar
Jim Blandy committed
1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
    return Qnil;

  args_left = args;
  GCPRO1 (args);

  do
    {
      val = Feval (Fcar (Fcdr (args_left)));
      sym = Fcar (args_left);
      Fset_default (sym, val);
      args_left = Fcdr (Fcdr (args_left));
    }
Jim Blandy's avatar
Jim Blandy committed
1084
  while (!NILP (args_left));
Jim Blandy's avatar
Jim Blandy committed
1085 1086 1087 1088 1089

  UNGCPRO;
  return val;
}

1090 1091
/* Lisp functions for creating and removing buffer-local variables.  */

Jim Blandy's avatar
Jim Blandy committed
1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103
DEFUN ("make-variable-buffer-local", Fmake_variable_buffer_local, Smake_variable_buffer_local,
  1, 1, "vMake Variable Buffer Local: ",
  "Make VARIABLE have a separate value for each buffer.\n\
At any time, the value for the current buffer is in effect.\n\
There is also a default value which is seen in any buffer which has not yet\n\
set its own value.\n\
Using `set' or `setq' to set the variable causes it to have a separate value\n\
for the current buffer if it was previously using the default value.\n\
The function `default-value' gets the default value and `set-default' sets it.")
  (sym)
     register Lisp_Object sym;
{
1104
  register Lisp_Object tem, valcontents, newval;
Jim Blandy's avatar
Jim Blandy committed
1105 1106 1107 1108 1109 1110 1111

  CHECK_SYMBOL (sym, 0);

  if (EQ (sym, Qnil) || EQ (sym, Qt))
    error ("Symbol %s may not be buffer-local", XSYMBOL (sym)->name->data);

  valcontents = XSYMBOL (sym)->value;
1112
  if (BUFFER_LOCAL_VALUEP (valcontents) || BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1113
    return sym;
1114
  if (SOME_BUFFER_LOCAL_VALUEP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1115
    {
1116
      XMISC (XSYMBOL (sym)->value)->type = Lisp_Misc_Buffer_Local_Value;
Jim Blandy's avatar
Jim Blandy committed
1117 1118 1119 1120 1121 1122
      return sym;
    }
  if (EQ (valcontents, Qunbound))
    XSYMBOL (sym)->value = Qnil;
  tem = Fcons (Qnil, Fsymbol_value (sym));
  XCONS (tem)->car = tem;
1123 1124 1125 1126 1127
  newval = allocate_misc ();
  XMISC (newval)->type = Lisp_Misc_Buffer_Local_Value;
  XBUFFER_LOCAL_VALUE (newval)->car = XSYMBOL (sym)->value;
  XBUFFER_LOCAL_VALUE (newval)->cdr = Fcons (Fcurrent_buffer (), tem);
  XSYMBOL (sym)->value = newval;
Jim Blandy's avatar
Jim Blandy committed
1128 1129 1130 1131 1132 1133 1134
  return sym;
}

DEFUN ("make-local-variable", Fmake_local_variable, Smake_local_variable,
  1, 1, "vMake Local Variable: ",
  "Make VARIABLE have a separate value in the current buffer.\n\
Other buffers will continue to share a common default value.\n\
1135 1136
\(The buffer-local value of VARIABLE starts out as the same value\n\
VARIABLE previously had.  If VARIABLE was void, it remains void.\)\n\
Jim Blandy's avatar
Jim Blandy committed
1137 1138 1139
See also `make-variable-buffer-local'.\n\n\
If the variable is already arranged to become local when set,\n\
this function causes a local value to exist for this buffer,\n\
1140 1141 1142 1143
just as setting the variable would do.\n\
\n\
Do not use `make-local-variable' to make a hook variable buffer-local.\n\
Use `make-local-hook' instead.")
Jim Blandy's avatar
Jim Blandy committed
1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154
  (sym)
     register Lisp_Object sym;
{
  register Lisp_Object tem, valcontents;

  CHECK_SYMBOL (sym, 0);

  if (EQ (sym, Qnil) || EQ (sym, Qt))
    error ("Symbol %s may not be buffer-local", XSYMBOL (sym)->name->data);

  valcontents = XSYMBOL (sym)->value;
1155
  if (BUFFER_LOCAL_VALUEP (valcontents) || BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1156 1157 1158 1159 1160 1161 1162 1163 1164
    {
      tem = Fboundp (sym);
      
      /* Make sure the symbol has a local value in this particular buffer,
	 by setting it to the same value it already has.  */
      Fset (sym, (EQ (tem, Qt) ? Fsymbol_value (sym) : Qunbound));
      return sym;
    }
  /* Make sure sym is set up to hold per-buffer values */
1165
  if (!SOME_BUFFER_LOCAL_VALUEP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1166
    {
1167
      Lisp_Object newval;
Jim Blandy's avatar
Jim Blandy committed
1168 1169
      tem = Fcons (Qnil, do_symval_forwarding (valcontents));
      XCONS (tem)->car = tem;
1170 1171 1172 1173 1174
      newval = allocate_misc ();
      XMISC (newval)->type = Lisp_Misc_Some_Buffer_Local_Value;
      XBUFFER_LOCAL_VALUE (newval)->car = XSYMBOL (sym)->value;
      XBUFFER_LOCAL_VALUE (newval)->cdr = Fcons (Qnil, tem);
      XSYMBOL (sym)->value = newval;
Jim Blandy's avatar
Jim Blandy committed
1175 1176 1177
    }
  /* Make sure this buffer has its own value of sym */
  tem = Fassq (sym, current_buffer->local_var_alist);
Jim Blandy's avatar
Jim Blandy committed
1178
  if (NILP (tem))
Jim Blandy's avatar
Jim Blandy committed
1179 1180
    {
      current_buffer->local_var_alist
1181
        = Fcons (Fcons (sym, XCONS (XCONS (XBUFFER_LOCAL_VALUE (XSYMBOL (sym)->value)->cdr)->cdr)->cdr),
Jim Blandy's avatar
Jim Blandy committed
1182 1183 1184 1185 1186
		 current_buffer->local_var_alist);

      /* Make sure symbol does not think it is set up for this buffer;
	 force it to look once again for this buffer's value */
      {
1187 1188 1189 1190 1191
	Lisp_Object *pvalbuf;
	valcontents = XSYMBOL (sym)->value;
	pvalbuf = &XCONS (XBUFFER_LOCAL_VALUE (valcontents)->cdr)->car;
	if (current_buffer == XBUFFER (*pvalbuf))
	  *pvalbuf = Qnil;
Jim Blandy's avatar
Jim Blandy committed
1192 1193
      }
    }
1194 1195 1196 1197 1198

  /* If the symbol forwards into a C variable, then swap in the
     variable for this buffer immediately.  If C code modifies the
     variable before we swap in, then that new value will clobber the
     default value the next time we swap.  */
1199
  valcontents = XBUFFER_LOCAL_VALUE (XSYMBOL (sym)->value)->car;
1200
  if (INTFWDP (valcontents) || BOOLFWDP (valcontents) || OBJFWDP (valcontents))
1201 1202
    swap_in_symval_forwarding (sym, XSYMBOL (sym)->value);

Jim Blandy's avatar
Jim Blandy committed
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218
  return sym;
}

DEFUN ("kill-local-variable", Fkill_local_variable, Skill_local_variable,
  1, 1, "vKill Local Variable: ",
  "Make VARIABLE no longer have a separate value in the current buffer.\n\
From now on the default value will apply in this buffer.")
  (sym)
     register Lisp_Object sym;
{
  register Lisp_Object tem, valcontents;

  CHECK_SYMBOL (sym, 0);

  valcontents = XSYMBOL (sym)->value;

1219
  if (BUFFER_OBJFWDP (valcontents))
Jim Blandy's avatar
Jim Blandy committed
1220
    {