lisp.h 126 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Fundamental definitions for GNU Emacs Lisp interpreter.
2
   Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 1998, 1999, 2000,
Glenn Morris's avatar
Glenn Morris committed
3
                 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Glenn Morris's avatar
Glenn Morris committed
4
                 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
5 6 7

This file is part of GNU Emacs.

8
GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
9
it under the terms of the GNU General Public License as published by
10 11
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
12 13 14 15 16 17 18

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
19
along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
Jim Blandy's avatar
Jim Blandy committed
20

Kenichi Handa's avatar
Kenichi Handa committed
21 22 23
#ifndef EMACS_LISP_H
#define EMACS_LISP_H

Gerd Moellmann's avatar
Gerd Moellmann committed
24 25 26
/* Declare the prototype for a general external function.  */
#define P_(proto) proto

27 28
/* Use the configure flag --enable-checking[=LIST] to enable various
   types of run time checks for Lisp objects.  */
29

30 31 32
#ifdef GC_CHECK_CONS_LIST
#define CHECK_CONS_LIST() check_cons_list()
#else
33
#define CHECK_CONS_LIST() ((void)0)
34
#endif
Jim Blandy's avatar
Jim Blandy committed
35

36
/* These are default choices for the types to use.  */
37 38 39 40 41 42 43 44 45
#ifdef _LP64
#ifndef EMACS_INT
#define EMACS_INT long
#define BITS_PER_EMACS_INT BITS_PER_LONG
#endif
#ifndef EMACS_UINT
#define EMACS_UINT unsigned long
#endif
#else /* not _LP64 */
46 47
#ifndef EMACS_INT
#define EMACS_INT int
Richard M. Stallman's avatar
Richard M. Stallman committed
48
#define BITS_PER_EMACS_INT BITS_PER_INT
49 50 51 52
#endif
#ifndef EMACS_UINT
#define EMACS_UINT unsigned int
#endif
53
#endif
54

55 56
/* Extra internal type checking?  */
extern int suppress_checking;
57
extern void die P_((const char *, const char *, int)) NO_RETURN;
58 59 60

#ifdef ENABLE_CHECKING

61 62 63 64 65 66 67 68 69 70 71 72 73 74
/* The suppress_checking variable is initialized to 0 in alloc.c.  Set
   it to 1 using a debugger to temporarily disable aborting on
   detected internal inconsistencies or error conditions.

   Testing suppress_checking after the supplied condition ensures that
   the side effects produced by CHECK will be consistent, independent
   of whether ENABLE_CHECKING is defined, or whether the checks are
   suppressed at run time.

   In some cases, a good compiler may be able to optimize away the
   CHECK macro altogether, e.g., if XSTRING (x) uses CHECK to test
   STRINGP (x), but a particular use of XSTRING is invoked only after
   testing that STRINGP (x) is true, making the test redundant.  */

75
#define CHECK(check,msg) (((check) || suppress_checking		\
76
			   ? (void) 0				\
77
			   : die ((msg), __FILE__, __LINE__)),	\
78
			  0)
79
#else
80

81 82
/* Produce same side effects and result, but don't complain.  */
#define CHECK(check,msg) ((check),0)
83

84
#endif
85

86 87
/* Define an Emacs version of "assert", since some system ones are
   flaky.  */
88 89 90
#ifndef ENABLE_CHECKING
#define eassert(X)	(void) 0
#else /* ENABLE_CHECKING */
91 92 93 94 95
#if defined (__GNUC__) && __GNUC__ >= 2 && defined (__STDC__)
#define eassert(cond) CHECK(cond,"assertion failed: " #cond)
#else
#define eassert(cond) CHECK(cond,"assertion failed")
#endif
96
#endif /* ENABLE_CHECKING */
97

Eli Zaretskii's avatar
Eli Zaretskii committed
98 99 100 101 102
/* Define this to make Lisp_Object use a union type instead of the
   default int.  FIXME: It might be better to add a flag to configure
   to do this.  */
/* #define USE_LISP_UNION_TYPE */

103 104
/***** Select the tagging scheme.  *****/
/* There are basically two options that control the tagging scheme:
Eli Zaretskii's avatar
Eli Zaretskii committed
105 106
   - USE_LISP_UNION_TYPE says that Lisp_Object should be a union instead
     of an integer.
107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134
   - USE_LSB_TAG means that we can assume the least 3 bits of pointers are
     always 0, and we can thus use them to hold tag bits, without
     restricting our addressing space.

   If USE_LSB_TAG is not set, then we use the top 3 bits for tagging, thus
   restricting our possible address range.  Currently USE_LSB_TAG is not
   allowed together with a union.  This is not due to any fundamental
   technical (or political ;-) problem: nobody wrote the code to do it yet.

   USE_LSB_TAG not only requires the least 3 bits of pointers returned by
   malloc to be 0 but also needs to be able to impose a mult-of-8 alignment
   on the few static Lisp_Objects used: all the defsubr as well
   as the two special buffers buffer_defaults and buffer_local_symbols.  */

/* First, try and define DECL_ALIGN(type,var) which declares a static
   variable VAR of type TYPE with the added requirement that it be
   TYPEBITS-aligned. */
#ifndef NO_DECL_ALIGN
# ifndef DECL_ALIGN
/* What compiler directive should we use for non-gcc compilers?  -stef  */
#  if defined (__GNUC__)
#   define DECL_ALIGN(type, var) \
     type __attribute__ ((__aligned__ (1 << GCTYPEBITS))) var
#  endif
# endif
#endif

/* Let's USE_LSB_TAG on systems where we know malloc returns mult-of-8.  */
135
#if defined GNU_MALLOC || defined DOUG_LEA_MALLOC || defined __GLIBC__ || defined DARWIN_OS
136 137
/* We also need to be able to specify mult-of-8 alignment on static vars.  */
# if defined DECL_ALIGN
138
#  define USE_LSB_TAG
139 140 141 142 143 144 145 146 147 148 149
# endif
#endif

/* If we cannot use 8-byte alignment, make DECL_ALIGN a no-op.  */
#ifndef DECL_ALIGN
# ifdef USE_LSB_TAG
#  error "USE_LSB_TAG used without defining DECL_ALIGN"
# endif
# define DECL_ALIGN(type, var) type var
#endif

150

151
/* Define the fundamental Lisp data structures.  */
Jim Blandy's avatar
Jim Blandy committed
152

153 154 155 156 157 158 159 160 161 162
/* If USE_2_TAGBITS_FOR_INTS is defined, then Lisp integers use
   2 tags, to give them one extra bit, thus extending their range from
   e.g -2^28..2^28-1 to -2^29..2^29-1.  */
#define USE_2_TAGS_FOR_INTS

/* Making it work for the union case is too much trouble.  */
#ifdef USE_LISP_UNION_TYPE
# undef USE_2_TAGS_FOR_INTS
#endif

163
/* This is the set of Lisp data types.  */
Jim Blandy's avatar
Jim Blandy committed
164

165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183
#if !defined USE_2_TAGS_FOR_INTS
# define LISP_INT_TAG Lisp_Int
# define case_Lisp_Int case Lisp_Int
# define LISP_STRING_TAG 4
# define LISP_INT_TAG_P(x) ((x) == Lisp_Int)
#else
# define LISP_INT_TAG Lisp_Int0
# define case_Lisp_Int case Lisp_Int0: case Lisp_Int1
# ifdef USE_LSB_TAG
#  define LISP_INT1_TAG 4
#  define LISP_STRING_TAG 1
#  define LISP_INT_TAG_P(x) (((x) & 3) == 0)
# else
#  define LISP_INT1_TAG 1
#  define LISP_STRING_TAG 4
#  define LISP_INT_TAG_P(x) (((x) & 6) == 0)
# endif
#endif

Jim Blandy's avatar
Jim Blandy committed
184 185
enum Lisp_Type
  {
186
    /* Integer.  XINT (obj) is the integer value.  */
187 188 189 190 191 192
#ifdef USE_2_TAGS_FOR_INTS
    Lisp_Int0 = 0,
    Lisp_Int1 = LISP_INT1_TAG,
#else
    Lisp_Int = 0,
#endif
Jim Blandy's avatar
Jim Blandy committed
193

194
    /* Symbol.  XSYMBOL (object) points to a struct Lisp_Symbol.  */
195
    Lisp_Symbol = 2,
Jim Blandy's avatar
Jim Blandy committed
196

197 198
    /* Miscellaneous.  XMISC (object) points to a union Lisp_Misc,
       whose first member indicates the subtype.  */
199
    Lisp_Misc = 3,
Jim Blandy's avatar
Jim Blandy committed
200 201

    /* String.  XSTRING (object) points to a struct Lisp_String.
202
       The length of the string, and its contents, are stored therein.  */
203
    Lisp_String = LISP_STRING_TAG,
Jim Blandy's avatar
Jim Blandy committed
204

205
    /* Vector of Lisp objects, or something resembling it.
206
       XVECTOR (object) points to a struct Lisp_Vector, which contains
207 208
       the size and contents.  The size field also contains the type
       information, if it's not a real vector object.  */
209
    Lisp_Vectorlike = 5,
Jim Blandy's avatar
Jim Blandy committed
210

211
    /* Cons.  XCONS (object) points to a struct Lisp_Cons.  */
212
    Lisp_Cons = 6,
213

214
    Lisp_Float = 7,
Jim Blandy's avatar
Jim Blandy committed
215 216
  };

217
/* This is the set of data types that share a common structure.
218 219 220 221
   The first member of the structure is a type code from this set.
   The enum values are arbitrary, but we'll use large numbers to make it
   more likely that we'll spot the error if a random word in memory is
   mistakenly interpreted as a Lisp_Misc.  */
Karl Heuer's avatar
Karl Heuer committed
222 223
enum Lisp_Misc_Type
  {
224
    Lisp_Misc_Free = 0x5eab,
225
    Lisp_Misc_Marker,
226
    Lisp_Misc_Overlay,
227
    Lisp_Misc_Save_Value,
228 229 230 231 232
    /* Currently floats are not a misc type,
       but let's define this in case we want to change that.  */
    Lisp_Misc_Float,
    /* This is not a type code.  It is for range checking.  */
    Lisp_Misc_Limit
Karl Heuer's avatar
Karl Heuer committed
233 234
  };

235 236 237 238 239 240 241 242 243 244 245 246
/* These are the types of forwarding objects used in the value slot
   of symbols for special built-in variables whose value is stored in
   C variables.  */
enum Lisp_Fwd_Type
  {
    Lisp_Fwd_Int,		/* Fwd to a C `int' variable.  */
    Lisp_Fwd_Bool,		/* Fwd to a C boolean var.  */
    Lisp_Fwd_Obj,		/* Fwd to a C Lisp_Object variable.  */
    Lisp_Fwd_Buffer_Obj,	/* Fwd to a Lisp_Object field of buffers.  */
    Lisp_Fwd_Kboard_Obj,	/* Fwd to a Lisp_Object field of kboards.  */
  };

247 248 249 250
#ifndef GCTYPEBITS
#define GCTYPEBITS 3
#endif

251 252
/* These values are overridden by the m- file on some machines.  */
#ifndef VALBITS
Kenichi Handa's avatar
Kenichi Handa committed
253
#define VALBITS (BITS_PER_EMACS_INT - GCTYPEBITS)
254 255
#endif

Eli Zaretskii's avatar
Eli Zaretskii committed
256
#ifdef USE_LISP_UNION_TYPE
Jim Blandy's avatar
Jim Blandy committed
257

258
#ifndef WORDS_BIG_ENDIAN
Jim Blandy's avatar
Jim Blandy committed
259 260 261 262 263 264 265

/* Definition of Lisp_Object for little-endian machines.  */

typedef
union Lisp_Object
  {
    /* Used for comparing two Lisp_Objects;
266
       also, positive integers can be accessed fast this way.  */
267
    EMACS_UINT i;
Jim Blandy's avatar
Jim Blandy committed
268 269 270

    struct
      {
271
	EMACS_INT val  : VALBITS;
Kenichi Handa's avatar
Kenichi Handa committed
272
	enum Lisp_Type type : GCTYPEBITS;
Jim Blandy's avatar
Jim Blandy committed
273 274 275
      } s;
    struct
      {
276
	EMACS_UINT val : VALBITS;
Kenichi Handa's avatar
Kenichi Handa committed
277
	enum Lisp_Type type : GCTYPEBITS;
Jim Blandy's avatar
Jim Blandy committed
278 279 280 281
      } u;
  }
Lisp_Object;

282
#else /* If WORDS_BIG_ENDIAN */
Jim Blandy's avatar
Jim Blandy committed
283 284 285 286 287

typedef
union Lisp_Object
  {
    /* Used for comparing two Lisp_Objects;
288
       also, positive integers can be accessed fast this way.  */
289
    EMACS_UINT i;
Jim Blandy's avatar
Jim Blandy committed
290 291 292

    struct
      {
Kenichi Handa's avatar
Kenichi Handa committed
293
	enum Lisp_Type type : GCTYPEBITS;
294
	EMACS_INT val  : VALBITS;
Jim Blandy's avatar
Jim Blandy committed
295 296 297
      } s;
    struct
      {
Kenichi Handa's avatar
Kenichi Handa committed
298
	enum Lisp_Type type : GCTYPEBITS;
299
	EMACS_UINT val : VALBITS;
Jim Blandy's avatar
Jim Blandy committed
300 301 302 303
      } u;
  }
Lisp_Object;

304
#endif /* WORDS_BIG_ENDIAN */
Jim Blandy's avatar
Jim Blandy committed
305

306 307 308 309 310 311 312
#ifdef __GNUC__
static __inline__ Lisp_Object
LISP_MAKE_RVALUE (Lisp_Object o)
{
    return o;
}
#else
313 314 315 316 317
/* This isn't quite right - it keeps the argument as an lvalue.
   Making it const via casting would help avoid code actually
   modifying the location in question, but the casting could cover
   other type-related bugs.  */
#define LISP_MAKE_RVALUE(o) (o)
318 319
#endif

Eli Zaretskii's avatar
Eli Zaretskii committed
320
#else /* USE_LISP_UNION_TYPE */
Jim Blandy's avatar
Jim Blandy committed
321

322
/* If union type is not wanted, define Lisp_Object as just a number.  */
Jim Blandy's avatar
Jim Blandy committed
323

324
typedef EMACS_INT Lisp_Object;
325
#define LISP_MAKE_RVALUE(o) (0+(o))
Eli Zaretskii's avatar
Eli Zaretskii committed
326
#endif /* USE_LISP_UNION_TYPE */
Jim Blandy's avatar
Jim Blandy committed
327

Stefan Monnier's avatar
Stefan Monnier committed
328
/* In the size word of a vector, this bit means the vector has been marked.  */
329

Stefan Monnier's avatar
Stefan Monnier committed
330
#define ARRAY_MARK_FLAG ((EMACS_UINT) 1 << (BITS_PER_EMACS_INT - 1))
331

332 333
/* In the size word of a struct Lisp_Vector, this bit means it's really
   some other vector-like object.  */
Stefan Monnier's avatar
Stefan Monnier committed
334
#define PSEUDOVECTOR_FLAG ((ARRAY_MARK_FLAG >> 1))
335

336
/* In a pseudovector, the size field actually contains a word with one
337
   PSEUDOVECTOR_FLAG bit set, and exactly one of the following bits to
338
   indicate the actual type.
339 340 341 342
   We use a bitset, even tho only one of the bits can be set at any
   particular time just so as to be able to use micro-optimizations such as
   testing membership of a particular subset of pseudovectors in Fequal.
   It is not crucial, but there are plenty of bits here, so why not do it?  */
343 344 345 346 347 348 349 350 351
enum pvec_type
{
  PVEC_NORMAL_VECTOR = 0,
  PVEC_PROCESS = 0x200,
  PVEC_FRAME = 0x400,
  PVEC_COMPILED = 0x800,
  PVEC_WINDOW = 0x1000,
  PVEC_WINDOW_CONFIGURATION = 0x2000,
  PVEC_SUBR = 0x4000,
352 353 354
  PVEC_CHAR_TABLE = 0x8000,
  PVEC_BOOL_VECTOR = 0x10000,
  PVEC_BUFFER = 0x20000,
Gerd Moellmann's avatar
Gerd Moellmann committed
355
  PVEC_HASH_TABLE = 0x40000,
356
  PVEC_TERMINAL = 0x80000,
Miles Bader's avatar
Miles Bader committed
357
  PVEC_SUB_CHAR_TABLE = 0x100000,
358 359 360
  PVEC_FONT = 0x200000,
  PVEC_OTHER = 0x400000,
  PVEC_TYPE_MASK = 0x7ffe00
361

Gerd Moellmann's avatar
Gerd Moellmann committed
362 363 364
#if 0 /* This is used to make the value of PSEUDOVECTOR_FLAG available to
	 GDB.  It doesn't work on OS Alpha.  Moved to a variable in
	 emacs.c.  */
365
  PVEC_FLAG = PSEUDOVECTOR_FLAG
Gerd Moellmann's avatar
Gerd Moellmann committed
366
#endif
367
};
368

369 370 371 372 373
/* For convenience, we also store the number of elements in these bits.
   Note that this size is not necessarily the memory-footprint size, but
   only the number of Lisp_Object fields (that need to be traced by the GC).
   The distinction is used e.g. by Lisp_Process which places extra
   non-Lisp_Object fields at the end of the structure.  */
374
#define PSEUDOVECTOR_SIZE_MASK 0x1ff
375 376 377 378

/* Number of bits to put in each character in the internal representation
   of bool vectors.  This should not vary across implementations.  */
#define BOOL_VECTOR_BITS_PER_CHAR 8
Jim Blandy's avatar
Jim Blandy committed
379 380 381

/* These macros extract various sorts of values from a Lisp_Object.
 For example, if tem is a Lisp_Object whose type is Lisp_Cons,
382
 XCONS (tem) is the struct Lisp_Cons * pointing to the memory for that cons.  */
Jim Blandy's avatar
Jim Blandy committed
383

Eli Zaretskii's avatar
Eli Zaretskii committed
384
#ifndef USE_LISP_UNION_TYPE
Jim Blandy's avatar
Jim Blandy committed
385

386 387 388
/* Return a perfect hash of the Lisp_Object representation.  */
#define XHASH(a) (a)

Kenichi Handa's avatar
Kenichi Handa committed
389 390 391 392
#ifdef USE_LSB_TAG

#define TYPEMASK ((((EMACS_INT) 1) << GCTYPEBITS) - 1)
#define XTYPE(a) ((enum Lisp_Type) (((EMACS_UINT) (a)) & TYPEMASK))
393 394 395 396 397 398 399 400 401
#ifdef USE_2_TAGS_FOR_INTS
# define XINT(a) (((EMACS_INT) (a)) >> (GCTYPEBITS - 1))
# define XUINT(a) (((EMACS_UINT) (a)) >> (GCTYPEBITS - 1))
# define make_number(N) (((EMACS_INT) (N)) << (GCTYPEBITS - 1))
#else
# define XINT(a) (((EMACS_INT) (a)) >> GCTYPEBITS)
# define XUINT(a) (((EMACS_UINT) (a)) >> GCTYPEBITS)
# define make_number(N) (((EMACS_INT) (N)) << GCTYPEBITS)
#endif
Kenichi Handa's avatar
Kenichi Handa committed
402 403 404 405 406 407 408 409 410 411
#define XSET(var, type, ptr)					\
    (eassert (XTYPE (ptr) == 0), /* Check alignment.  */	\
     (var) = ((EMACS_INT) (type)) | ((EMACS_INT) (ptr)))

#define XPNTR(a) ((EMACS_INT) ((a) & ~TYPEMASK))

#else  /* not USE_LSB_TAG */

#define VALMASK ((((EMACS_INT) 1) << VALBITS) - 1)

Jim Blandy's avatar
Jim Blandy committed
412 413
/* One need to override this if there must be high bits set in data space
   (doing the result of the below & ((1 << (GCTYPE + 1)) - 1) would work
414
    on all machines, but would penalize machines which don't need it)
Jim Blandy's avatar
Jim Blandy committed
415
 */
Kenichi Handa's avatar
Kenichi Handa committed
416
#define XTYPE(a) ((enum Lisp_Type) (((EMACS_UINT) (a)) >> VALBITS))
Jim Blandy's avatar
Jim Blandy committed
417

Karl Heuer's avatar
Karl Heuer committed
418 419
/* For integers known to be positive, XFASTINT provides fast retrieval
   and XSETFASTINT provides fast storage.  This takes advantage of the
Kenichi Handa's avatar
Kenichi Handa committed
420
   fact that Lisp_Int is 0.  */
421
#define XFASTINT(a) ((a) + 0)
Karl Heuer's avatar
Karl Heuer committed
422
#define XSETFASTINT(a, b) ((a) = (b))
Jim Blandy's avatar
Jim Blandy committed
423

424
/* Extract the value of a Lisp_Object as a (un)signed integer.  */
Jim Blandy's avatar
Jim Blandy committed
425

426 427 428 429 430 431
#ifdef USE_2_TAGS_FOR_INTS
# define XINT(a) ((((EMACS_INT) (a)) << (GCTYPEBITS - 1)) >> (GCTYPEBITS - 1))
# define XUINT(a) ((EMACS_UINT) ((a) & (1 + (VALMASK << 1))))
# define make_number(N) ((((EMACS_INT) (N)) & (1 + (VALMASK << 1))))
#else
# define XINT(a) ((((EMACS_INT) (a)) << (BITS_PER_EMACS_INT - VALBITS))	\
Kenichi Handa's avatar
Kenichi Handa committed
432
		 >> (BITS_PER_EMACS_INT - VALBITS))
433 434 435
# define XUINT(a) ((EMACS_UINT) ((a) & VALMASK))
# define make_number(N)		\
  ((((EMACS_INT) (N)) & VALMASK) | ((EMACS_INT) Lisp_Int) << VALBITS)
Jim Blandy's avatar
Jim Blandy committed
436 437 438
#endif

#define XSET(var, type, ptr) \
439
   ((var) = ((EMACS_INT)(type) << VALBITS) + ((EMACS_INT) (ptr) & VALMASK))
440

441
#define XPNTR(a) ((EMACS_UINT) ((a) & VALMASK))
442

Kenichi Handa's avatar
Kenichi Handa committed
443
#endif /* not USE_LSB_TAG */
Jim Blandy's avatar
Jim Blandy committed
444

Eli Zaretskii's avatar
Eli Zaretskii committed
445
#else /* USE_LISP_UNION_TYPE */
Jim Blandy's avatar
Jim Blandy committed
446

447 448 449 450
#ifdef USE_2_TAGS_FOR_INTS
# error "USE_2_TAGS_FOR_INTS is not supported with USE_LISP_UNION_TYPE"
#endif

451 452
#define XHASH(a) ((a).i)

Jim Blandy's avatar
Jim Blandy committed
453 454 455
#define XTYPE(a) ((enum Lisp_Type) (a).u.type)

#ifdef EXPLICIT_SIGN_EXTEND
456 457 458 459 460
/* Make sure we sign-extend; compilers have been known to fail to do so.
   We additionally cast to EMACS_INT since it seems that some compilers
   have been known to fail to do so, even though the bitfield is declared
   as EMACS_INT already.  */
#define XINT(a) ((((EMACS_INT) (a).s.val) << (BITS_PER_EMACS_INT - VALBITS)) \
461
		 >> (BITS_PER_EMACS_INT - VALBITS))
Jim Blandy's avatar
Jim Blandy committed
462 463 464 465 466 467
#else
#define XINT(a) ((a).s.val)
#endif /* EXPLICIT_SIGN_EXTEND */

#define XUINT(a) ((a).u.val)

468 469 470 471 472 473 474
#ifdef USE_LSB_TAG

# define XSET(var, vartype, ptr) \
  (eassert ((((EMACS_UINT) (ptr)) & ((1 << GCTYPEBITS) - 1)) == 0),	\
   (var).u.val = ((EMACS_UINT) (ptr)) >> GCTYPEBITS,			\
   (var).u.type = ((char) (vartype)))

475 476 477 478
/* Some versions of gcc seem to consider the bitfield width when issuing
   the "cast to pointer from integer of different size" warning, so the
   cast is here to widen the value back to its natural size.  */
# define XPNTR(v) ((EMACS_INT)((v).s.val) << GCTYPEBITS)
479 480 481 482 483 484 485 486 487 488

#else  /* !USE_LSB_TAG */

/* For integers known to be positive, XFASTINT provides fast retrieval
   and XSETFASTINT provides fast storage.  This takes advantage of the
   fact that Lisp_Int is 0.  */
# define XFASTINT(a) ((a).i + 0)
# define XSETFASTINT(a, b) ((a).i = (b))

# define XSET(var, vartype, ptr) \
489
   (((var).s.val = ((EMACS_INT) (ptr))), ((var).s.type = ((char) (vartype))))
Jim Blandy's avatar
Jim Blandy committed
490

491 492
#endif	/* !USE_LSB_TAG */

493 494 495 496
#if __GNUC__ >= 2 && defined (__OPTIMIZE__)
#define make_number(N) \
  (__extension__ ({ Lisp_Object _l; _l.s.val = (N); _l.s.type = Lisp_Int; _l; }))
#else
497
extern Lisp_Object make_number P_ ((EMACS_INT));
498
#endif
499

Eli Zaretskii's avatar
Eli Zaretskii committed
500
#endif /* USE_LISP_UNION_TYPE */
Kenichi Handa's avatar
Kenichi Handa committed
501

502 503 504 505 506 507 508 509
/* For integers known to be positive, XFASTINT sometimes provides
   faster retrieval and XSETFASTINT provides faster storage.
   If not, fallback on the non-accelerated path.  */
#ifndef XFASTINT
# define XFASTINT(a) (XINT (a))
# define XSETFASTINT(a, b) (XSETINT (a, b))
#endif

510 511
#define EQ(x, y) (XHASH (x) == XHASH (y))

512 513 514 515 516 517 518 519 520 521 522 523 524 525 526
#ifndef XPNTR
#ifdef HAVE_SHM
/* In this representation, data is found in two widely separated segments.  */
extern size_t pure_size;
#define XPNTR(a) \
  (XUINT (a) | (XUINT (a) > pure_size ? DATA_SEG_BITS : PURE_SEG_BITS))
#else /* not HAVE_SHM */
#ifdef DATA_SEG_BITS
/* This case is used for the rt-pc.
   In the diffs I was given, it checked for ptr = 0
   and did not adjust it in that case.
   But I don't think that zero should ever be found
   in a Lisp object whose data type says it points to something.  */
#define XPNTR(a) (XUINT (a) | DATA_SEG_BITS)
#else
527 528 529 530 531
/* Some versions of gcc seem to consider the bitfield width when
   issuing the "cast to pointer from integer of different size"
   warning, so the cast is here to widen the value back to its natural
   size.  */
#define XPNTR(a) ((EMACS_INT) XUINT (a))
532 533 534 535
#endif
#endif /* not HAVE_SHM */
#endif /* no XPNTR */

Gerd Moellmann's avatar
Gerd Moellmann committed
536 537
/* Largest and smallest representable fixnum values.  These are the C
   values.  */
538

539 540 541
#ifdef USE_2_TAGS_FOR_INTS
# define MOST_NEGATIVE_FIXNUM	- ((EMACS_INT) 1 << VALBITS)
# define MOST_POSITIVE_FIXNUM	(((EMACS_INT) 1 << VALBITS) - 1)
Kenichi Handa's avatar
Kenichi Handa committed
542 543
/* Mask indicating the significant bits of a Lisp_Int.
   I.e. (x & INTMASK) == XUINT (make_number (x)).  */
544 545 546 547 548 549 550 551
# define INTMASK ((((EMACS_INT) 1) << (VALBITS + 1)) - 1)
#else
# define MOST_NEGATIVE_FIXNUM	- ((EMACS_INT) 1 << (VALBITS - 1))
# define MOST_POSITIVE_FIXNUM	(((EMACS_INT) 1 << (VALBITS - 1)) - 1)
/* Mask indicating the significant bits of a Lisp_Int.
   I.e. (x & INTMASK) == XUINT (make_number (x)).  */
# define INTMASK ((((EMACS_INT) 1) << VALBITS) - 1)
#endif
552

553 554 555
/* Value is non-zero if I doesn't fit into a Lisp fixnum.  It is
   written this way so that it also works if I is of unsigned
   type.  */
556 557

#define FIXNUM_OVERFLOW_P(i) \
558
  ((i) > MOST_POSITIVE_FIXNUM \
559
   || ((i) < 0 && (i) < MOST_NEGATIVE_FIXNUM))
560

561
/* Extract a value or address from a Lisp_Object.  */
Jim Blandy's avatar
Jim Blandy committed
562

563 564 565 566 567
#define XCONS(a) (eassert (CONSP(a)),(struct Lisp_Cons *) XPNTR(a))
#define XVECTOR(a) (eassert (VECTORLIKEP(a)),(struct Lisp_Vector *) XPNTR(a))
#define XSTRING(a) (eassert (STRINGP(a)),(struct Lisp_String *) XPNTR(a))
#define XSYMBOL(a) (eassert (SYMBOLP(a)),(struct Lisp_Symbol *) XPNTR(a))
#define XFLOAT(a) (eassert (FLOATP(a)),(struct Lisp_Float *) XPNTR(a))
568 569

/* Misc types.  */
570

571
#define XMISC(a)   ((union Lisp_Misc *) XPNTR(a))
572
#define XMISCANY(a)	(eassert (MISCP (a)), &(XMISC(a)->u_any))
573
#define XMISCTYPE(a)   (XMISCANY (a)->type)
574 575 576
#define XMARKER(a)	(eassert (MARKERP (a)), &(XMISC(a)->u_marker))
#define XOVERLAY(a)	(eassert (OVERLAYP (a)), &(XMISC(a)->u_overlay))
#define XSAVE_VALUE(a)	(eassert (SAVE_VALUEP (a)), &(XMISC(a)->u_save_value))
577 578 579 580 581 582 583

/* Forwarding object types.  */

#define XFWDTYPE(a)     (a->u_intfwd.type)
#define XINTFWD(a)	(eassert (INTFWDP (a)), &((a)->u_intfwd))
#define XBOOLFWD(a)	(eassert (BOOLFWDP (a)), &((a)->u_boolfwd))
#define XOBJFWD(a)	(eassert (OBJFWDP (a)), &((a)->u_objfwd))
584
#define XBUFFER_OBJFWD(a) \
585
  (eassert (BUFFER_OBJFWDP (a)), &((a)->u_buffer_objfwd))
586
#define XKBOARD_OBJFWD(a) \
587
  (eassert (KBOARD_OBJFWDP (a)), &((a)->u_kboard_objfwd))
Jim Blandy's avatar
Jim Blandy committed
588

589
/* Pseudovector types.  */
590

591 592
#define XPROCESS(a) (eassert (PROCESSP(a)),(struct Lisp_Process *) XPNTR(a))
#define XWINDOW(a) (eassert (WINDOWP(a)),(struct window *) XPNTR(a))
Miles Bader's avatar
Miles Bader committed
593
#define XTERMINAL(a) (eassert (TERMINALP(a)),(struct terminal *) XPNTR(a))
594 595
#define XSUBR(a) (eassert (SUBRP(a)),(struct Lisp_Subr *) XPNTR(a))
#define XBUFFER(a) (eassert (BUFFERP(a)),(struct buffer *) XPNTR(a))
Miles Bader's avatar
Miles Bader committed
596 597 598
#define XCHAR_TABLE(a) (eassert (CHAR_TABLE_P (a)), (struct Lisp_Char_Table *) XPNTR(a))
#define XSUB_CHAR_TABLE(a) (eassert (SUB_CHAR_TABLE_P (a)), (struct Lisp_Sub_Char_Table *) XPNTR(a))
#define XBOOL_VECTOR(a) (eassert (BOOL_VECTOR_P (a)), (struct Lisp_Bool_Vector *) XPNTR(a))
599 600

/* Construct a Lisp_Object from a value or address.  */
601

602
#define XSETINT(a, b) (a) = make_number (b)
603
#define XSETCONS(a, b) XSET (a, Lisp_Cons, b)
604
#define XSETVECTOR(a, b) XSET (a, Lisp_Vectorlike, b)
605 606 607
#define XSETSTRING(a, b) XSET (a, Lisp_String, b)
#define XSETSYMBOL(a, b) XSET (a, Lisp_Symbol, b)
#define XSETFLOAT(a, b) XSET (a, Lisp_Float, b)
608 609

/* Misc types.  */
610

611
#define XSETMISC(a, b) XSET (a, Lisp_Misc, b)
Richard M. Stallman's avatar
Richard M. Stallman committed
612
#define XSETMARKER(a, b) (XSETMISC (a, b), XMISCTYPE (a) = Lisp_Misc_Marker)
613 614

/* Pseudovector types.  */
615

616
#define XSETPVECTYPE(v,code) ((v)->size |= PSEUDOVECTOR_FLAG | (code))
617
#define XSETPSEUDOVECTOR(a, b, code) \
618 619 620
  (XSETVECTOR (a, b),							\
   eassert ((XVECTOR (a)->size & (PSEUDOVECTOR_FLAG | PVEC_TYPE_MASK))	\
	    == (PSEUDOVECTOR_FLAG | (code))))
621 622 623 624
#define XSETWINDOW_CONFIGURATION(a, b) \
  (XSETPSEUDOVECTOR (a, b, PVEC_WINDOW_CONFIGURATION))
#define XSETPROCESS(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_PROCESS))
#define XSETWINDOW(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_WINDOW))
625
#define XSETTERMINAL(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_TERMINAL))
626 627
#define XSETSUBR(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_SUBR))
#define XSETCOMPILED(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_COMPILED))
628
#define XSETBUFFER(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_BUFFER))
629 630
#define XSETCHAR_TABLE(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_CHAR_TABLE))
#define XSETBOOL_VECTOR(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_BOOL_VECTOR))
631
#define XSETSUB_CHAR_TABLE(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_SUB_CHAR_TABLE))
632 633 634

/* Convenience macros for dealing with Lisp arrays.  */

635
#define AREF(ARRAY, IDX)	XVECTOR ((ARRAY))->contents[IDX]
636
#define ASIZE(ARRAY)		XVECTOR ((ARRAY))->size
637
/* The IDX==IDX tries to detect when the macro argument is side-effecting.  */
Stefan Monnier's avatar
Stefan Monnier committed
638 639 640
#define ASET(ARRAY, IDX, VAL)	\
  (eassert ((IDX) == (IDX)),				\
   eassert ((IDX) >= 0 && (IDX) < ASIZE (ARRAY)),	\
641
   AREF ((ARRAY), (IDX)) = (VAL))
642

643 644
/* Convenience macros for dealing with Lisp strings.  */

Ken Raeburn's avatar
Ken Raeburn committed
645
#define SDATA(string)		(XSTRING (string)->data + 0)
646 647
#define SREF(string, index)	(SDATA (string)[index] + 0)
#define SSET(string, index, new) (SDATA (string)[index] = (new))
648 649 650 651 652
#define SCHARS(string)		(XSTRING (string)->size + 0)
#define SBYTES(string)		(STRING_BYTES (XSTRING (string)) + 0)

#define STRING_SET_CHARS(string, newsize) \
    (XSTRING (string)->size = (newsize))
653

Ken Raeburn's avatar
Ken Raeburn committed
654
#define STRING_COPYIN(string, index, new, count) \
655
    bcopy (new, SDATA (string) + index, count)
Ken Raeburn's avatar
Ken Raeburn committed
656

657 658 659 660 661 662
/* Type checking.  */

#define CHECK_TYPE(ok, Qxxxp, x) \
  do { if (!(ok)) wrong_type_argument (Qxxxp, (x)); } while (0)


Jim Blandy's avatar
Jim Blandy committed
663

664
/* See the macros in intervals.h.  */
665 666 667 668

typedef struct interval *INTERVAL;

/* Complain if object is not string or buffer type */
669
#define CHECK_STRING_OR_BUFFER(x) \
670 671
  CHECK_TYPE (STRINGP (x) || BUFFERP (x), Qbuffer_or_string_p, x)

672

Jim Blandy's avatar
Jim Blandy committed
673 674 675 676
/* In a cons, the markbit of the car is the gc mark bit */

struct Lisp_Cons
  {
677 678 679
    /* Please do not use the names of these elements in code other
       than the core lisp implementation.  Use XCAR and XCDR below.  */
#ifdef HIDE_LISP_IMPLEMENTATION
680 681 682 683 684 685
    Lisp_Object car_;
    union
    {
      Lisp_Object cdr_;
      struct Lisp_Cons *chain;
    } u;
686
#else
687 688 689 690 691 692
    Lisp_Object car;
    union
    {
      Lisp_Object cdr;
      struct Lisp_Cons *chain;
    } u;
693
#endif
Jim Blandy's avatar
Jim Blandy committed
694 695
  };

696
/* Take the car or cdr of something known to be a cons cell.  */
697 698 699 700 701 702
/* The _AS_LVALUE macros shouldn't be used outside of the minimal set
   of code that has to know what a cons cell looks like.  Other code not
   part of the basic lisp implementation should assume that the car and cdr
   fields are not accessible as lvalues.  (What if we want to switch to
   a copying collector someday?  Cached cons cell field addresses may be
   invalidated at arbitrary points.)  */
703
#ifdef HIDE_LISP_IMPLEMENTATION
704
#define XCAR_AS_LVALUE(c) (XCONS ((c))->car_)
705
#define XCDR_AS_LVALUE(c) (XCONS ((c))->u.cdr_)
706
#else
707
#define XCAR_AS_LVALUE(c) (XCONS ((c))->car)
708
#define XCDR_AS_LVALUE(c) (XCONS ((c))->u.cdr)
709
#endif
710

711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728
/* Use these from normal code.  */
#define XCAR(c)	LISP_MAKE_RVALUE(XCAR_AS_LVALUE(c))
#define XCDR(c) LISP_MAKE_RVALUE(XCDR_AS_LVALUE(c))

/* Use these to set the fields of a cons cell.

   Note that both arguments may refer to the same object, so 'n'
   should not be read after 'c' is first modified.  Also, neither
   argument should be evaluated more than once; side effects are
   especially common in the second argument.  */
#define XSETCAR(c,n) (XCAR_AS_LVALUE(c) = (n))
#define XSETCDR(c,n) (XCDR_AS_LVALUE(c) = (n))

/* For performance: Fast storage of positive integers into the
   fields of a cons cell.  See above caveats.  */
#define XSETCARFASTINT(c,n)  XSETFASTINT(XCAR_AS_LVALUE(c),(n))
#define XSETCDRFASTINT(c,n)  XSETFASTINT(XCDR_AS_LVALUE(c),(n))

729 730 731 732
/* Take the car or cdr of something whose type is not known.  */
#define CAR(c)					\
 (CONSP ((c)) ? XCAR ((c))			\
  : NILP ((c)) ? Qnil				\
733
  : wrong_type_argument (Qlistp, (c)))
734 735 736 737

#define CDR(c)					\
 (CONSP ((c)) ? XCDR ((c))			\
  : NILP ((c)) ? Qnil				\
738
  : wrong_type_argument (Qlistp, (c)))
739

740 741 742 743 744 745 746
/* Take the car or cdr of something whose type is not known.  */
#define CAR_SAFE(c)				\
  (CONSP ((c)) ? XCAR ((c)) : Qnil)

#define CDR_SAFE(c)				\
  (CONSP ((c)) ? XCDR ((c)) : Qnil)

Kenichi Handa's avatar
Kenichi Handa committed
747 748 749 750 751
/* Nonzero if STR is a multibyte string.  */
#define STRING_MULTIBYTE(STR)  \
  (XSTRING (STR)->size_byte >= 0)

/* Return the length in bytes of STR.  */
752 753 754 755 756 757 758 759 760

#ifdef GC_CHECK_STRING_BYTES

struct Lisp_String;
extern int string_bytes P_ ((struct Lisp_String *));
#define STRING_BYTES(S) string_bytes ((S))

#else /* not GC_CHECK_STRING_BYTES */

Kenichi Handa's avatar
Kenichi Handa committed
761 762 763
#define STRING_BYTES(STR)  \
  ((STR)->size_byte < 0 ? (STR)->size : (STR)->size_byte)

764 765
#endif /* not GC_CHECK_STRING_BYTES */

766
/* Mark STR as a unibyte string.  */
767 768 769 770
#define STRING_SET_UNIBYTE(STR)  \
  do { if (EQ (STR, empty_multibyte_string))  \
      (STR) = empty_unibyte_string;  \
    else XSTRING (STR)->size_byte = -1; } while (0)
771

772 773 774 775 776 777 778
/* Mark STR as a multibyte string.  Assure that STR contains only
   ASCII characters in advance.  */
#define STRING_SET_MULTIBYTE(STR)  \
  do { if (EQ (STR, empty_unibyte_string))  \
      (STR) = empty_multibyte_string;  \
    else XSTRING (STR)->size_byte = XSTRING (STR)->size; } while (0)

779
/* Get text properties.  */
780 781 782 783
#define STRING_INTERVALS(STR)  (XSTRING (STR)->intervals + 0)

/* Set text properties.  */
#define STRING_SET_INTERVALS(STR, INT) (XSTRING (STR)->intervals = (INT))
Kenichi Handa's avatar
Kenichi Handa committed
784

Jim Blandy's avatar
Jim Blandy committed
785 786 787 788
/* In a string or vector, the sign bit of the `size' is the gc mark bit */

struct Lisp_String
  {
789
    EMACS_INT size;
790
    EMACS_INT size_byte;
791
    INTERVAL intervals;		/* text properties in this string */
792
    unsigned char *data;
Jim Blandy's avatar
Jim Blandy committed
793 794
  };

795 796 797 798 799 800
#ifdef offsetof
#define OFFSETOF(type,field) offsetof(type,field)
#else
#define OFFSETOF(type,field) \
  ((int)((char*)&((type*)0)->field - (char*)0))
#endif
Karl Heuer's avatar
Karl Heuer committed
801

Jim Blandy's avatar
Jim Blandy committed
802 803
struct Lisp_Vector
  {
Stefan Monnier's avatar
Stefan Monnier committed
804
    EMACS_UINT size;
Jim Blandy's avatar
Jim Blandy committed
805 806 807 808
    struct Lisp_Vector *next;
    Lisp_Object contents[1];
  };

Karl Heuer's avatar
Karl Heuer committed
809
/* If a struct is made to look like a vector, this macro returns the length
810
   of the shortest vector that would hold that struct.  */
Andreas Schwab's avatar
Andreas Schwab committed
811 812 813
#define VECSIZE(type) ((sizeof (type)					  \
			- OFFSETOF (struct Lisp_Vector, contents[0])      \
                        + sizeof(Lisp_Object) - 1) /* round up */	  \
Karl Heuer's avatar
Karl Heuer committed
814 815
		       / sizeof (Lisp_Object))

816 817 818 819
/* Like VECSIZE, but used when the pseudo-vector has non-Lisp_Object fields
   at the end and we need to compute the number of Lisp_Object fields (the
   ones that the GC needs to trace).  */
#define PSEUDOVECSIZE(type, nonlispfield) \
820
  ((OFFSETOF(type, nonlispfield) - OFFSETOF(struct Lisp_Vector, contents[0])) \
821 822
   / sizeof (Lisp_Object))

823
/* A char-table is a kind of vectorlike, with contents are like a
824
   vector but with a few other slots.  For some purposes, it makes
825
   sense to handle a char-table with type struct Lisp_Vector.  An
826 827
   element of a char table can be any Lisp objects, but if it is a sub
   char-table, we treat it a table that contains information of a
828 829 830 831
   specific range of characters.  A sub char-table has the same
   structure as a vector.  A sub char table appears only in an element
   of a char-table, and there's no way to access it directly from
   Emacs Lisp program.  */
832

833 834 835
/* This is the number of slots that every char table must have.  This
   counts the ordinary slots and the top, defalt, parent, and purpose
   slots.  */
836
#define CHAR_TABLE_STANDARD_SLOTS (VECSIZE (struct Lisp_Char_Table) - 1)
837 838 839 840 841 842

/* Return the number of "extra" slots in the char table CT.  */

#define CHAR_TABLE_EXTRA_SLOTS(CT)	\
  (((CT)->size & PSEUDOVECTOR_SIZE_MASK) - CHAR_TABLE_STANDARD_SLOTS)

843 844 845 846 847 848 849 850 851 852 853 854 855
#ifdef __GNUC__

#define CHAR_TABLE_REF_ASCII(CT, IDX)					\
  ({struct Lisp_Char_Table *_tbl = NULL;				\
    Lisp_Object _val;							\
    do {								\
      _tbl = _tbl ? XCHAR_TABLE (_tbl->parent) : XCHAR_TABLE (CT);	\
      _val = (! SUB_CHAR_TABLE_P (_tbl->ascii) ? _tbl->ascii		\
	      : XSUB_CHAR_TABLE (_tbl->ascii)->contents[IDX]);		\
      if (NILP (_val))							\
	_val = _tbl->defalt;						\
    } while (NILP (_val) && ! NILP (_tbl->parent));			\
    _val; })
856

857 858 859 860 861 862 863 864 865 866 867 868 869
#else  /* not __GNUC__ */

#define CHAR_TABLE_REF_ASCII(CT, IDX)					  \
  (! NILP (XCHAR_TABLE (CT)->ascii)					  \
   ? (! SUB_CHAR_TABLE_P (XCHAR_TABLE (CT)->ascii)			  \
      ? XCHAR_TABLE (CT)->ascii						  \
      : ! NILP (XSUB_CHAR_TABLE (XCHAR_TABLE (CT)->ascii)->contents[IDX]) \
      ? XSUB_CHAR_TABLE (XCHAR_TABLE (CT)->ascii)->contents[IDX]	  \
      : char_table_ref ((CT), (IDX)))					  \
   :  char_table_ref ((CT), (IDX)))

#endif	/* not __GNUC__ */

870
/* Almost equivalent to Faref (CT, IDX) with optimization for ASCII
871
   characters.  Do not check validity of CT.  */
872 873
#define CHAR_TABLE_REF(CT, IDX)					\
  (ASCII_CHAR_P (IDX) ? CHAR_TABLE_REF_ASCII ((CT), (IDX))	\
874
   : char_table_ref ((CT), (IDX)))
875

Kenichi Handa's avatar
Kenichi Handa committed
876 877
/* Almost equivalent to Faref (CT, IDX).  However, if the result is
   not a character, return IDX.
878 879 880

   For these characters, do not check validity of CT
   and do not follow parent.  */
881 882
#define CHAR_TABLE_TRANSLATE(CT, IDX)	\
  char_table_translate (CT, IDX)
883

884
/* Equivalent to Faset (CT, IDX, VAL) with optimization for ASCII and
Dave Love's avatar
Dave Love committed
885
   8-bit European characters.  Do not check validity of CT.  */
886 887 888 889 890 891 892 893 894 895 896 897 898 899
#define CHAR_TABLE_SET(CT, IDX, VAL)					\
  (((IDX) >= 0 && ASCII_CHAR_P (IDX)					\
    && SUB_CHAR_TABLE_P (XCHAR_TABLE (CT)->ascii))			\
   ? XSUB_CHAR_TABLE (XCHAR_TABLE (CT)->ascii)->contents[IDX] = VAL	\
   : char_table_set (CT, IDX, VAL))

#define CHARTAB_SIZE_BITS_0 6
#define CHARTAB_SIZE_BITS_1 4
#define CHARTAB_SIZE_BITS_2 5
#define CHARTAB_SIZE_BITS_3 7

extern const int chartab_size[4];

struct Lisp_Sub_Char_Table;
900

901 902 903 904
struct Lisp_Char_Table
  {
    /* This is the vector's size field, which also holds the
       pseudovector type information.  It holds the size, too.
Miles Bader's avatar
Miles Bader committed
905 906
       The size counts the defalt, parent, purpose, ascii,
       contents, and extras slots.  */
Stefan Monnier's avatar
Stefan Monnier committed
907
    EMACS_UINT size;
908
    struct Lisp_Vector *next;
909

910 911 912
    /* This holds a default value,
       which is used whenever the value for a specific character is nil.  */
    Lisp_Object defalt;
913

Kenichi Handa's avatar
Kenichi Handa committed
914 915 916
    /* This points to another char table, which we inherit from when the
       value for a specific character is nil.  The `defalt' slot takes
       precedence over this.  */
917
    Lisp_Object parent;
918

Kenichi Handa's avatar
Kenichi Handa committed
919 920
    /* This is a symbol which says what kind of use this char-table is
       meant for.  */
921
    Lisp_Object purpose;
922

Kenichi Handa's avatar
Kenichi Handa committed
923 924 925
    /* The bottom sub char-table for characters of the range 0..127.  It
       is nil if none of ASCII character has a specific value.  */
    Lisp_Object ascii;
926

Kenichi Handa's avatar
Kenichi Handa committed
927
    Lisp_Object contents[(1 << CHARTAB_SIZE_BITS_0)];
928

Kenichi Handa's avatar
Kenichi Handa committed
929
    /* These hold additional data.  It is a vector.  */
930 931 932
    Lisp_Object extras[1];
  };

933
struct Lisp_Sub_Char_Table
Kenichi Handa's avatar
Kenichi Handa committed
934 935 936 937 938
  {
    /* This is the vector's size field, which also holds the
       pseudovector type information.  It holds the size, too.  */
    EMACS_INT size;
    struct Lisp_Vector *next;
939

Kenichi Handa's avatar
Kenichi Handa committed
940 941 942 943 944 945 946
    /* Depth of this sub char-table.  It should be 1, 2, or 3.  A sub
       char-table of depth 1 contains 16 elments, and each element
       covers 4096 (128*32) characters.  A sub char-table of depth 2
       contains 32 elements, and each element covers 128 characters.  A
       sub char-table of depth 3 contains 128 elements, and each element
       is for one character.  */
    Lisp_Object depth;
947

Kenichi Handa's avatar
Kenichi Handa committed
948 949
    /* Minimum character covered by the sub char-table.  */
    Lisp_Object min_char;
950

Kenichi Handa's avatar
Kenichi Handa committed
951 952
    Lisp_Object contents[1];
  };
953 954 955 956 957 958

/* A boolvector is a kind of vectorlike, with contents are like a string.  */
struct Lisp_Bool_Vector
  {
    /* This is the vector's size field.  It doesn't have the real size,
       just the subtype information.  */
Stefan Monnier's avatar
Stefan Monnier committed
959
    EMACS_UINT vector_size;
960 961
    struct Lisp_Vector *next;
    /* This is the size in bits.  */
Stefan Monnier's avatar
Stefan Monnier committed
962
    EMACS_UINT size;
963 964 965 966
    /* This contains the actual bits, packed into bytes.  */
    unsigned char data[1];
  };

967 968 969 970 971 972 973
/* This structure describes a built-in function.
   It is generated by the DEFUN macro only.
   defsubr makes it into a Lisp object.

   This type is treated in most respects as a pseudovector,
   but since we never dynamically allocate or free them,
   we don't need a next-vector field.  */
974

Jim Blandy's avatar
Jim Blandy committed
975 976
struct Lisp_Subr
  {
Stefan Monnier's avatar
Stefan Monnier committed
977
    EMACS_UINT size;
Jim Blandy's avatar
Jim Blandy committed
978 979
    Lisp_Object (*function) ();
    short min_args, max_args;
980
    const char *symbol_name;
981
    char *intspec;
Jim Blandy's avatar
Jim Blandy committed
982 983
    char *doc;
  };
Gerd Moellmann's avatar
Gerd Moellmann committed
984

985 986 987 988 989 990 991 992 993 994 995 996 997 998

/***********************************************************************
			       Symbols
 ***********************************************************************/

/* Interned state of a symbol.  */

enum symbol_interned
{
  SYMBOL_UNINTERNED = 0,
  SYMBOL_INTERNED = 1,
  SYMBOL_INTERNED_IN_INITIAL_OBARRAY = 2
};

999 1000 1001 1002 1003 1004 1005 1006
enum symbol_redirect
{
  SYMBOL_PLAINVAL  = 4,
  SYMBOL_VARALIAS  = 1,
  SYMBOL_LOCALIZED = 2,
  SYMBOL_FORWARDED   = 3
};

1007 1008 1009 1010
/* In a symbol, the markbit of the plist is used as the gc mark bit */

struct Lisp_Symbol
{
1011 1012
  unsigned gcmarkbit : 1;

1013 1014 1015 1016 1017 1018 1019
  /* Indicates where the value can be found:
     0 : it's a plain var, the value is in the `value' field.
     1 : it's a varalias, the value is really in the `alias' symbol.
     2 : it's a localized var, the value is in the `blv' object.
     3 : it's a forwarding variable, the value is in `forward'.
   */
  enum symbol_redirect redirect : 3;
1020 1021

  /* Non-zero means symbol is constant, i.e. changing its value
1022 1023 1024
     should signal an error.  If the value is 3, then the var
     can be changed, but only by `defconst'.  */
  unsigned constant : 2;
1025 1026 1027 1028 1029

  /* Interned state of the symbol.  This is an enumerator from
     enum symbol_interned.  */
  unsigned interned : 2;

1030 1031 1032 1033 1034
  /* The symbol's name, as a Lisp string.

     The name "xname" is used to intentionally break code referring to
     the old field "name" of type pointer to struct Lisp_String.  */
  Lisp_Object xname;
1035 1036

  /* Value of the symbol or Qunbound if unbound.  If this symbol is a
1037
     defvaralias, `alias' contains the symbol for which it is an
1038 1039
     alias.  Use the SYMBOL_VALUE and SET_SYMBOL_VALUE macros to get
     and set a symbol's value, to take defvaralias into account.  */
1040 1041 1042 1043 1044 1045
  union {
    Lisp_Object value;
    struct Lisp_Symbol *alias;
    struct Lisp_Buffer_Local_Value *blv;
    union Lisp_Fwd *fwd;
  } val;
1046

1047
  /* Function value of the symbol or Qunbound if not fboundp.  */
1048 1049 1050 1051
  Lisp_Object function;

  /* The symbol's property list.  */
  Lisp_Object plist;
1052

1053 1054 1055 1056
  /* Next symbol in obarray bucket, if the symbol is interned.  */
  struct Lisp_Symbol *next;
};

1057 1058
/* Value is name of symbol.  */

1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075
#define SYMBOL_VAL(sym)   \
  (eassert ((sym)->redirect == SYMBOL_PLAINVAL),  (sym)->val.value)
#define SYMBOL_ALIAS(sym) \
  (eassert ((sym)->redirect == SYMBOL_VARALIAS),  (sym)->val.alias)
#define SYMBOL_BLV(sym)   \
  (eassert ((sym)->redirect == SYMBOL_LOCALIZED), (sym)->val.blv)
#define SYMBOL_FWD(sym)   \
  (eassert ((sym)->redirect == SYMBOL_FORWARDED), (sym)->val.fwd)
#define SET_SYMBOL_VAL(sym, v)     \
  (eassert ((sym)->redirect == SYMBOL_PLAINVAL),  (sym)->val.value = (v))
#define SET_SYMBOL_ALIAS(sym, v)   \
  (eassert ((sym)->redirect == SYMBOL_VARALIAS),  (sym)->val.alias = (v))
#define SET_SYMBOL_BLV(sym, v)     \
  (eassert ((sym)->redirect == SYMBOL_LOCALIZED), (sym)->val.blv = (v))
#define SET_SYMBOL_FWD(sym, v) \
  (eassert ((sym)->redirect == SYMBOL_FORWARDED), (sym)->val.fwd = (v))

1076 1077 1078
#define SYMBOL_NAME(sym)  \
     LISP_MAKE_RVALUE (XSYMBOL (sym)->xname)

1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
/* Value is non-zero if SYM is an interned symbol.  */

#define SYMBOL_INTERNED_P(sym)  \
     (XSYMBOL (sym)->interned != SYMBOL_UNINTERNED)

/* Value is non-zero if SYM is interned in initial_obarray.  */

#define SYMBOL_INTERNED_IN_INITIAL_OBARRAY_P(sym) \
     (XSYMBOL (sym)->interned == SYMBOL_INTERNED_IN_INITIAL_OBARRAY)

/* Value is non-zero if symbol is considered a constant, i.e. its
   value cannot be changed (there is an exception for keyword symbols,
   whose value can be set to the keyword symbol itself).  */

#define SYMBOL_CONSTANT_P(sym)   XSYMBOL (sym)->constant

Gerd Moellmann's avatar
Gerd Moellmann committed
1095 1096 1097 1098 1099 1100 1101 1102 1103 1104

/***********************************************************************
			     Hash Tables
 ***********************************************************************/

/* The structure of a Lisp hash table.  */

struct Lisp_Hash_Table
{
  /* Vector fields.  The hash table code doesn't refer to these.  */
Stefan Monnier's avatar
Stefan Monnier committed
1105
  EMACS_UINT size;
Gerd Moellmann's avatar
Gerd Moellmann committed
1106
  struct Lisp_Vector *vec_next;
1107

Gerd Moellmann's avatar
Gerd Moellmann committed
1108 1109 1110 1111 1112 1113
  /* Function used to compare keys.  */
  Lisp_Object test;

  /* Nil if table is non-weak.  Otherwise a symbol describing the
     weakness of the table.  */
  Lisp_Object weak;
1114

Gerd Moellmann's avatar
Gerd Moellmann committed
1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146
  /* When the table is resized, and this is an integer, compute the
     new size by adding this to the old size.  If a float, compute the
     new size by multiplying the old size with this factor.  */
  Lisp_Object rehash_size;

  /* Resize hash table when number of entries/ table size is >= this
     ratio, a float.  */
  Lisp_Object rehash_threshold;

  /* Vector of hash codes.. If hash[I] is nil, this means that that
     entry I is unused.  */
  Lisp_Object hash;

  /* Vector used to chain entries.  If entry I is free, next[I] is the
     entry number of the next free item.  If entry I is non-free,
     next[I] is the index of the next entry in the collision chain.  */
  Lisp_Object next;

  /* Index of first free entry in free list.  */
  Lisp_Object next_free;

  /* Bucket vector.  A non-nil entry is the index of the first item in
     a collision chain.  This vector's size can be larger than the
     hash table size to reduce collisions.  */
  Lisp_Object index;

  /* User-supplied hash function, or nil.  */
  Lisp_Object user_hash_function;

  /* User-supplied key comparison function, or nil.  */
  Lisp_Object user_cmp_function;

1147 1148 </