gcc/obstack.h

   1 /* obstack.h - object stack macros
   2    Copyright (C) 1988,89,90,91,92,93,94,96,97 Free Software Foundation, Inc.
   3
   4    the C library, however.  The master source lives in /gd/gnu/lib.
   5
   6    NOTE: The canonical source of this file is maintained with the GNU C Library.
   7    Bugs can be reported to bug-glibc@prep.ai.mit.edu.
   8
   9    This program is free software; you can redistribute it and/or modify it
  10    under the terms of the GNU General Public License as published by the
  11    Free Software Foundation; either version 2, or (at your option) any
  12    later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  22    USA.  */
  23
  24 /* Summary:
  25
  26 All the apparent functions defined here are macros. The idea
  27 is that you would use these pre-tested macros to solve a
  28 very specific set of problems, and they would run fast.
  29 Caution: no side-effects in arguments please!! They may be
  30 evaluated MANY times!!
  31
  32 These macros operate a stack of objects.  Each object starts life
  33 small, and may grow to maturity.  (Consider building a word syllable
  34 by syllable.)  An object can move while it is growing.  Once it has
  35 been "finished" it never changes address again.  So the "top of the
  36 stack" is typically an immature growing object, while the rest of the
  37 stack is of mature, fixed size and fixed address objects.
  38
  39 These routines grab large chunks of memory, using a function you
  40 supply, called `obstack_chunk_alloc'.  On occasion, they free chunks,
  41 by calling `obstack_chunk_free'.  You must define them and declare
  42 them before using any obstack macros.
  43
  44 Each independent stack is represented by a `struct obstack'.
  45 Each of the obstack macros expects a pointer to such a structure
  46 as the first argument.
  47
  48 One motivation for this package is the problem of growing char strings
  49 in symbol tables.  Unless you are "fascist pig with a read-only mind"
  50 --Gosper's immortal quote from HAKMEM item 154, out of context--you
  51 would not like to put any arbitrary upper limit on the length of your
  52 symbols.
  53
  54 In practice this often means you will build many short symbols and a
  55 few long symbols.  At the time you are reading a symbol you don't know
  56 how long it is.  One traditional method is to read a symbol into a
  57 buffer, realloc()ating the buffer every time you try to read a symbol
  58 that is longer than the buffer.  This is beaut, but you still will
  59 want to copy the symbol from the buffer to a more permanent
  60 symbol-table entry say about half the time.
  61
  62 With obstacks, you can work differently.  Use one obstack for all symbol
  63 names.  As you read a symbol, grow the name in the obstack gradually.
  64 When the name is complete, finalize it.  Then, if the symbol exists already,
  65 free the newly read name.
  66
  67 The way we do this is to take a large chunk, allocating memory from
  68 low addresses.  When you want to build a symbol in the chunk you just
  69 add chars above the current "high water mark" in the chunk.  When you
  70 have finished adding chars, because you got to the end of the symbol,
  71 you know how long the chars are, and you can create a new object.
  72 Mostly the chars will not burst over the highest address of the chunk,
  73 because you would typically expect a chunk to be (say) 100 times as
  74 long as an average object.
  75
  76 In case that isn't clear, when we have enough chars to make up
  77 the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed)
  78 so we just point to it where it lies.  No moving of chars is
  79 needed and this is the second win: potentially long strings need
  80 never be explicitly shuffled. Once an object is formed, it does not
  81 change its address during its lifetime.
  82
  83 When the chars burst over a chunk boundary, we allocate a larger
  84 chunk, and then copy the partly formed object from the end of the old
  85 chunk to the beginning of the new larger chunk.  We then carry on
  86 accreting characters to the end of the object as we normally would.
  87
  88 A special macro is provided to add a single char at a time to a
  89 growing object.  This allows the use of register variables, which
  90 break the ordinary 'growth' macro.
  91
  92 Summary:
  93         We allocate large chunks.
  94         We carve out one object at a time from the current chunk.
  95         Once carved, an object never moves.
  96         We are free to append data of any size to the currently
  97           growing object.
  98         Exactly one object is growing in an obstack at any one time.
  99         You can run one obstack per control block.
 100         You may have as many control blocks as you dare.
 101         Because of the way we do it, you can `unwind' an obstack
 102           back to a previous state. (You may remove objects much
 103           as you would with a stack.)
 104 */
 105
 106
 107 /* Don't do the contents of this file more than once.  */
 108
 109 #ifndef _OBSTACK_H
 110 #define _OBSTACK_H 1
 111
 112 #ifdef __cplusplus
 113 extern "C" {
 114 #endif
 115 \f
 116 /* We use subtraction of (char *) 0 instead of casting to int
 117    because on word-addressable machines a simple cast to int
 118    may ignore the byte-within-word field of the pointer.  */
 119
 120 #ifndef __PTR_TO_INT
 121 #define __PTR_TO_INT(P) ((P) - (char *) 0)
 122 #endif
 123
 124 #ifndef __INT_TO_PTR
 125 #define __INT_TO_PTR(P) ((P) + (char *) 0)
 126 #endif
 127
 128 /* We need the type of the resulting object.  In ANSI C it is ptrdiff_t
 129    but in traditional C it is usually long.  If we are in ANSI C and
 130    don't already have ptrdiff_t get it.  */
 131
 132 #if defined (__STDC__) && __STDC__ && ! defined (offsetof)
 133 #if defined (__GNUC__) && defined (IN_GCC)
 134 /* On Next machine, the system's stddef.h screws up if included
 135    after we have defined just ptrdiff_t, so include all of stddef.h.
 136    Otherwise, define just ptrdiff_t, which is all we need.  */
 137 #ifndef __NeXT__
 138 #define __need_ptrdiff_t
 139 #endif
 140 #endif
 141
 142 #include <stddef.h>
 143 #endif
 144
 145 #if defined (__STDC__) && __STDC__
 146 #define PTR_INT_TYPE ptrdiff_t
 147 #else
 148 #define PTR_INT_TYPE long
 149 #endif
 150
 151 #if defined (_LIBC) || defined (HAVE_STRING_H)
 152 #include <string.h>
 153 #define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 154 #else
 155 #ifdef memcpy
 156 #define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 157 #else
 158 #define _obstack_memcpy(To, From, N) bcopy ((From), (To), (N))
 159 #endif
 160 #endif
 161
 162 struct _obstack_chunk           /* Lives at front of each chunk. */
 163 {
 164   char  *limit;                 /* 1 past end of this chunk */
 165   struct _obstack_chunk *prev;  /* address of prior chunk or NULL */
 166   char  contents[4];            /* objects begin here */
 167 };
 168
 169 struct obstack          /* control current object in current chunk */
 170 {
 171   long  chunk_size;             /* preferred size to allocate chunks in */
 172   struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */
 173   char  *object_base;           /* address of object we are building */
 174   char  *next_free;             /* where to add next char to current object */
 175   char  *chunk_limit;           /* address of char after current chunk */
 176   PTR_INT_TYPE temp;            /* Temporary for some macros.  */
 177   int   alignment_mask;         /* Mask of alignment for each object. */
 178 #if defined (__STDC__) && __STDC__
 179   /* These prototypes vary based on `use_extra_arg', and we use
 180      casts to the prototypeless function type in all assignments,
 181      but having prototypes here quiets -Wstrict-prototypes.  */
 182   struct _obstack_chunk *(*chunkfun) (void *, long);
 183   void (*freefun) (void *, struct _obstack_chunk *);
 184   void *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 185 #else
 186   struct _obstack_chunk *(*chunkfun) (); /* User's fcn to allocate a chunk.  */
 187   void (*freefun) ();           /* User's function to free a chunk.  */
 188   char *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 189 #endif
 190   unsigned use_extra_arg:1;     /* chunk alloc/dealloc funcs take extra arg */
 191   unsigned maybe_empty_object:1;/* There is a possibility that the current
 192                                    chunk contains a zero-length object.  This
 193                                    prevents freeing the chunk if we allocate
 194                                    a bigger chunk to replace it. */
 195   unsigned alloc_failed:1;      /* No longer used, as we now call the failed
 196                                    handler on error, but retained for binary
 197                                    compatibility.  */
 198 };
 199
 200 /* Declare the external functions we use; they are in obstack.c.  */
 201
 202 #if defined (__STDC__) && __STDC__
 203 extern void _obstack_newchunk (struct obstack *, int);
 204 extern void _obstack_free (struct obstack *, void *);
 205 extern int _obstack_begin (struct obstack *, int, int,
 206                             void *(*) (long), void (*) (void *));
 207 extern int _obstack_begin_1 (struct obstack *, int, int,
 208                              void *(*) (void *, long),
 209                              void (*) (void *, void *), void *);
 210 extern int _obstack_memory_used (struct obstack *);
 211 #else
 212 extern void _obstack_newchunk ();
 213 extern void _obstack_free ();
 214 extern int _obstack_begin ();
 215 extern int _obstack_begin_1 ();
 216 extern int _obstack_memory_used ();
 217 #endif
 218 \f
 219 #if defined (__STDC__) && __STDC__
 220
 221 /* Do the function-declarations after the structs
 222    but before defining the macros.  */
 223
 224 void obstack_init (struct obstack *obstack);
 225
 226 void * obstack_alloc (struct obstack *obstack, int size);
 227
 228 void * obstack_copy (struct obstack *obstack, void *address, int size);
 229 void * obstack_copy0 (struct obstack *obstack, void *address, int size);
 230
 231 void obstack_free (struct obstack *obstack, void *block);
 232
 233 void obstack_blank (struct obstack *obstack, int size);
 234
 235 void obstack_grow (struct obstack *obstack, void *data, int size);
 236 void obstack_grow0 (struct obstack *obstack, void *data, int size);
 237
 238 void obstack_1grow (struct obstack *obstack, int data_char);
 239 void obstack_ptr_grow (struct obstack *obstack, void *data);
 240 void obstack_int_grow (struct obstack *obstack, int data);
 241
 242 void * obstack_finish (struct obstack *obstack);
 243
 244 int obstack_object_size (struct obstack *obstack);
 245
 246 int obstack_room (struct obstack *obstack);
 247 void obstack_make_room (struct obstack *obstack, int size);
 248 void obstack_1grow_fast (struct obstack *obstack, int data_char);
 249 void obstack_ptr_grow_fast (struct obstack *obstack, void *data);
 250 void obstack_int_grow_fast (struct obstack *obstack, int data);
 251 void obstack_blank_fast (struct obstack *obstack, int size);
 252
 253 void * obstack_base (struct obstack *obstack);
 254 void * obstack_next_free (struct obstack *obstack);
 255 int obstack_alignment_mask (struct obstack *obstack);
 256 int obstack_chunk_size (struct obstack *obstack);
 257 int obstack_memory_used (struct obstack *obstack);
 258
 259 #endif /* __STDC__ */
 260
 261 /* Non-ANSI C cannot really support alternative functions for these macros,
 262    so we do not declare them.  */
 263
 264 /* Error handler called when `obstack_chunk_alloc' failed to allocate
 265    more memory.  This can be set to a user defined function.  The
 266    default action is to print a message and abort.  */
 267 #if defined (__STDC__) && __STDC__
 268 extern void (*obstack_alloc_failed_handler) (void);
 269 #else
 270 extern void (*obstack_alloc_failed_handler) ();
 271 #endif
 272
 273 /* Exit value used when `print_and_abort' is used.  */
 274 extern int obstack_exit_failure;
 275 \f
 276 /* Pointer to beginning of object being allocated or to be allocated next.
 277    Note that this might not be the final address of the object
 278    because a new chunk might be needed to hold the final size.  */
 279
 280 #define obstack_base(h) ((h)->object_base)
 281
 282 /* Size for allocating ordinary chunks.  */
 283
 284 #define obstack_chunk_size(h) ((h)->chunk_size)
 285
 286 /* Pointer to next byte not yet allocated in current chunk.  */
 287
 288 #define obstack_next_free(h)    ((h)->next_free)
 289
 290 /* Mask specifying low bits that should be clear in address of an object.  */
 291
 292 #define obstack_alignment_mask(h) ((h)->alignment_mask)
 293
 294 /* To prevent prototype warnings provide complete argument list in
 295    standard C version.  */
 296 #if defined (__STDC__) && __STDC__
 297
 298 #define obstack_init(h) \
 299   _obstack_begin ((h), 0, 0, \
 300                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 301
 302 #define obstack_begin(h, size) \
 303   _obstack_begin ((h), (size), 0, \
 304                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 305
 306 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 307   _obstack_begin ((h), (size), (alignment), \
 308                     (void *(*) (long)) (chunkfun), (void (*) (void *)) (freefun))
 309
 310 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 311   _obstack_begin_1 ((h), (size), (alignment), \
 312                     (void *(*) (void *, long)) (chunkfun), \
 313                     (void (*) (void *, void *)) (freefun), (arg))
 314
 315 #define obstack_chunkfun(h, newchunkfun) \
 316   ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
 317
 318 #define obstack_freefun(h, newfreefun) \
 319   ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
 320
 321 #else
 322
 323 #define obstack_init(h) \
 324   _obstack_begin ((h), 0, 0, \
 325                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 326
 327 #define obstack_begin(h, size) \
 328   _obstack_begin ((h), (size), 0, \
 329                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 330
 331 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 332   _obstack_begin ((h), (size), (alignment), \
 333                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun))
 334
 335 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 336   _obstack_begin_1 ((h), (size), (alignment), \
 337                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun), (arg))
 338
 339 #define obstack_chunkfun(h, newchunkfun) \
 340   ((h) -> chunkfun = (struct _obstack_chunk *(*)()) (newchunkfun))
 341
 342 #define obstack_freefun(h, newfreefun) \
 343   ((h) -> freefun = (void (*)()) (newfreefun))
 344
 345 #endif
 346
 347 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = achar)
 348
 349 #define obstack_blank_fast(h,n) ((h)->next_free += (n))
 350
 351 #define obstack_memory_used(h) _obstack_memory_used (h)
 352 \f
 353 #if defined (__GNUC__) && defined (__STDC__) && __STDC__
 354 /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and
 355    does not implement __extension__.  But that compiler doesn't define
 356    __GNUC_MINOR__.  */
 357 #if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__)
 358 #define __extension__
 359 #endif
 360
 361 /* For GNU C, if not -traditional,
 362    we can define these macros to compute all args only once
 363    without using a global variable.
 364    Also, we can avoid using the `temp' slot, to make faster code.  */
 365
 366 #define obstack_object_size(OBSTACK)                                    \
 367   __extension__                                                         \
 368   ({ struct obstack *__o = (OBSTACK);                                   \
 369      (unsigned) (__o->next_free - __o->object_base); })
 370
 371 #define obstack_room(OBSTACK)                                           \
 372   __extension__                                                         \
 373   ({ struct obstack *__o = (OBSTACK);                                   \
 374      (unsigned) (__o->chunk_limit - __o->next_free); })
 375
 376 #define obstack_make_room(OBSTACK,length)                               \
 377 __extension__                                                           \
 378 ({ struct obstack *__o = (OBSTACK);                                     \
 379    int __len = (length);                                                \
 380    if (__o->chunk_limit - __o->next_free < __len)                       \
 381      _obstack_newchunk (__o, __len);                                    \
 382    (void) 0; })
 383
 384 #define obstack_grow(OBSTACK,where,length)                              \
 385 __extension__                                                           \
 386 ({ struct obstack *__o = (OBSTACK);                                     \
 387    int __len = (length);                                                \
 388    if (__o->next_free + __len > __o->chunk_limit)                       \
 389      _obstack_newchunk (__o, __len);                                    \
 390    _obstack_memcpy (__o->next_free, (char *) (where), __len);           \
 391    __o->next_free += __len;                                             \
 392    (void) 0; })
 393
 394 #define obstack_grow0(OBSTACK,where,length)                             \
 395 __extension__                                                           \
 396 ({ struct obstack *__o = (OBSTACK);                                     \
 397    int __len = (length);                                                \
 398    if (__o->next_free + __len + 1 > __o->chunk_limit)                   \
 399      _obstack_newchunk (__o, __len + 1);                                \
 400    _obstack_memcpy (__o->next_free, (char *) (where), __len);           \
 401    __o->next_free += __len;                                             \
 402    *(__o->next_free)++ = 0;                                             \
 403    (void) 0; })
 404
 405 #define obstack_1grow(OBSTACK,datum)                                    \
 406 __extension__                                                           \
 407 ({ struct obstack *__o = (OBSTACK);                                     \
 408    if (__o->next_free + 1 > __o->chunk_limit)                           \
 409      _obstack_newchunk (__o, 1);                                        \
 410    *(__o->next_free)++ = (datum);                                       \
 411    (void) 0; })
 412
 413 /* These assume that the obstack alignment is good enough for pointers or ints,
 414    and that the data added so far to the current object
 415    shares that much alignment.  */
 416
 417 #define obstack_ptr_grow(OBSTACK,datum)                                 \
 418 __extension__                                                           \
 419 ({ struct obstack *__o = (OBSTACK);                                     \
 420    if (__o->next_free + sizeof (void *) > __o->chunk_limit)             \
 421      _obstack_newchunk (__o, sizeof (void *));                          \
 422    *((void **)__o->next_free)++ = ((void *)datum);                      \
 423    (void) 0; })
 424
 425 #define obstack_int_grow(OBSTACK,datum)                                 \
 426 __extension__                                                           \
 427 ({ struct obstack *__o = (OBSTACK);                                     \
 428    if (__o->next_free + sizeof (int) > __o->chunk_limit)                \
 429      _obstack_newchunk (__o, sizeof (int));                             \
 430    *((int *)__o->next_free)++ = ((int)datum);                           \
 431    (void) 0; })
 432
 433 #define obstack_ptr_grow_fast(h,aptr) (*((void **) (h)->next_free)++ = (void *)aptr)
 434 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 435
 436 #define obstack_blank(OBSTACK,length)                                   \
 437 __extension__                                                           \
 438 ({ struct obstack *__o = (OBSTACK);                                     \
 439    int __len = (length);                                                \
 440    if (__o->chunk_limit - __o->next_free < __len)                       \
 441      _obstack_newchunk (__o, __len);                                    \
 442    __o->next_free += __len;                                             \
 443    (void) 0; })
 444
 445 #define obstack_alloc(OBSTACK,length)                                   \
 446 __extension__                                                           \
 447 ({ struct obstack *__h = (OBSTACK);                                     \
 448    obstack_blank (__h, (length));                                       \
 449    obstack_finish (__h); })
 450
 451 #define obstack_copy(OBSTACK,where,length)                              \
 452 __extension__                                                           \
 453 ({ struct obstack *__h = (OBSTACK);                                     \
 454    obstack_grow (__h, (where), (length));                               \
 455    obstack_finish (__h); })
 456
 457 #define obstack_copy0(OBSTACK,where,length)                             \
 458 __extension__                                                           \
 459 ({ struct obstack *__h = (OBSTACK);                                     \
 460    obstack_grow0 (__h, (where), (length));                              \
 461    obstack_finish (__h); })
 462
 463 /* The local variable is named __o1 to avoid a name conflict
 464    when obstack_blank is called.  */
 465 #define obstack_finish(OBSTACK)                                         \
 466 __extension__                                                           \
 467 ({ struct obstack *__o1 = (OBSTACK);                                    \
 468    void *value;                                                         \
 469    value = (void *) __o1->object_base;                                  \
 470    if (__o1->next_free == value)                                        \
 471      __o1->maybe_empty_object = 1;                                      \
 472    __o1->next_free                                                      \
 473      = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\
 474                      & ~ (__o1->alignment_mask));                       \
 475    if (__o1->next_free - (char *)__o1->chunk                            \
 476        > __o1->chunk_limit - (char *)__o1->chunk)                       \
 477      __o1->next_free = __o1->chunk_limit;                               \
 478    __o1->object_base = __o1->next_free;                                 \
 479    value; })
 480
 481 #define obstack_free(OBSTACK, OBJ)                                      \
 482 __extension__                                                           \
 483 ({ struct obstack *__o = (OBSTACK);                                     \
 484    void *__obj = (OBJ);                                                 \
 485    if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit)  \
 486      __o->next_free = __o->object_base = __obj;                         \
 487    else (obstack_free) (__o, __obj); })
 488 \f
 489 #else /* not __GNUC__ or not __STDC__ */
 490
 491 #define obstack_object_size(h) \
 492  (unsigned) ((h)->next_free - (h)->object_base)
 493
 494 #define obstack_room(h)         \
 495  (unsigned) ((h)->chunk_limit - (h)->next_free)
 496
 497 /* Note that the call to _obstack_newchunk is enclosed in (..., 0)
 498    so that we can avoid having void expressions
 499    in the arms of the conditional expression.
 500    Casting the third operand to void was tried before,
 501    but some compilers won't accept it.  */
 502
 503 #define obstack_make_room(h,length)                                     \
 504 ( (h)->temp = (length),                                                 \
 505   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 506    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0))
 507
 508 #define obstack_grow(h,where,length)                                    \
 509 ( (h)->temp = (length),                                                 \
 510   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 511    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 512   _obstack_memcpy ((h)->next_free, (char *) (where), (h)->temp),        \
 513   (h)->next_free += (h)->temp)
 514
 515 #define obstack_grow0(h,where,length)                                   \
 516 ( (h)->temp = (length),                                                 \
 517   (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit)                  \
 518    ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0),                  \
 519   _obstack_memcpy ((h)->next_free, (char *) (where), (h)->temp),        \
 520   (h)->next_free += (h)->temp,                                          \
 521   *((h)->next_free)++ = 0)
 522
 523 #define obstack_1grow(h,datum)                                          \
 524 ( (((h)->next_free + 1 > (h)->chunk_limit)                              \
 525    ? (_obstack_newchunk ((h), 1), 0) : 0),                              \
 526   (*((h)->next_free)++ = (datum)))
 527
 528 #define obstack_ptr_grow(h,datum)                                       \
 529 ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit)                \
 530    ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0),                \
 531   (*((char **) (((h)->next_free+=sizeof(char *))-sizeof(char *))) = ((char *) datum)))
 532
 533 #define obstack_int_grow(h,datum)                                       \
 534 ( (((h)->next_free + sizeof (int) > (h)->chunk_limit)                   \
 535    ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0),                   \
 536   (*((int *) (((h)->next_free+=sizeof(int))-sizeof(int))) = ((int) datum)))
 537
 538 #define obstack_ptr_grow_fast(h,aptr) (*((char **) (h)->next_free)++ = (char *) aptr)
 539 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 540
 541 #define obstack_blank(h,length)                                         \
 542 ( (h)->temp = (length),                                                 \
 543   (((h)->chunk_limit - (h)->next_free < (h)->temp)                      \
 544    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 545   ((h)->next_free += (h)->temp))
 546
 547 #define obstack_alloc(h,length)                                         \
 548  (obstack_blank ((h), (length)), obstack_finish ((h)))
 549
 550 #define obstack_copy(h,where,length)                                    \
 551  (obstack_grow ((h), (where), (length)), obstack_finish ((h)))
 552
 553 #define obstack_copy0(h,where,length)                                   \
 554  (obstack_grow0 ((h), (where), (length)), obstack_finish ((h)))
 555
 556 #define obstack_finish(h)                                               \
 557 ( ((h)->next_free == (h)->object_base                                   \
 558    ? (((h)->maybe_empty_object = 1), 0)                                 \
 559    : 0),                                                                \
 560   (h)->temp = __PTR_TO_INT ((h)->object_base),                          \
 561   (h)->next_free                                                        \
 562     = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \
 563                     & ~ ((h)->alignment_mask)),                         \
 564   (((h)->next_free - (char *) (h)->chunk                                \
 565     > (h)->chunk_limit - (char *) (h)->chunk)                           \
 566    ? ((h)->next_free = (h)->chunk_limit) : 0),                          \
 567   (h)->object_base = (h)->next_free,                                    \
 568   __INT_TO_PTR ((h)->temp))
 569
 570 #if defined (__STDC__) && __STDC__
 571 #define obstack_free(h,obj)                                             \
 572 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 573   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 574    ? (int) ((h)->next_free = (h)->object_base                           \
 575             = (h)->temp + (char *) (h)->chunk)                          \
 576    : (((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0), 0)))
 577 #else
 578 #define obstack_free(h,obj)                                             \
 579 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 580   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 581    ? (int) ((h)->next_free = (h)->object_base                           \
 582             = (h)->temp + (char *) (h)->chunk)                          \
 583    : (_obstack_free ((h), (h)->temp + (char *) (h)->chunk), 0)))
 584 #endif
 585
 586 #endif /* not __GNUC__ or not __STDC__ */
 587
 588 #ifdef __cplusplus
 589 }       /* C++ */
 590 #endif
 591
 592 #endif /* obstack.h */