include/obstack.h

   1 /* obstack.h - object stack macros
   2    Copyright (C) 1988-2015 Free Software Foundation, Inc.
   3
   4
   5    NOTE: The canonical source of this file is maintained with the GNU C Library.
   6    Bugs can be reported to bug-glibc@gnu.org.
   7
   8    This program is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published by the
  10    Free Software Foundation; either version 2, or (at your option) any
  11    later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301,
  21    USA.  */
  22
  23 /* Summary:
  24
  25 All the apparent functions defined here are macros. The idea
  26 is that you would use these pre-tested macros to solve a
  27 very specific set of problems, and they would run fast.
  28 Caution: no side-effects in arguments please!! They may be
  29 evaluated MANY times!!
  30
  31 These macros operate a stack of objects.  Each object starts life
  32 small, and may grow to maturity.  (Consider building a word syllable
  33 by syllable.)  An object can move while it is growing.  Once it has
  34 been "finished" it never changes address again.  So the "top of the
  35 stack" is typically an immature growing object, while the rest of the
  36 stack is of mature, fixed size and fixed address objects.
  37
  38 These routines grab large chunks of memory, using a function you
  39 supply, called `obstack_chunk_alloc'.  On occasion, they free chunks,
  40 by calling `obstack_chunk_free'.  You must define them and declare
  41 them before using any obstack macros.
  42
  43 Each independent stack is represented by a `struct obstack'.
  44 Each of the obstack macros expects a pointer to such a structure
  45 as the first argument.
  46
  47 One motivation for this package is the problem of growing char strings
  48 in symbol tables.  Unless you are "fascist pig with a read-only mind"
  49 --Gosper's immortal quote from HAKMEM item 154, out of context--you
  50 would not like to put any arbitrary upper limit on the length of your
  51 symbols.
  52
  53 In practice this often means you will build many short symbols and a
  54 few long symbols.  At the time you are reading a symbol you don't know
  55 how long it is.  One traditional method is to read a symbol into a
  56 buffer, realloc()ating the buffer every time you try to read a symbol
  57 that is longer than the buffer.  This is beaut, but you still will
  58 want to copy the symbol from the buffer to a more permanent
  59 symbol-table entry say about half the time.
  60
  61 With obstacks, you can work differently.  Use one obstack for all symbol
  62 names.  As you read a symbol, grow the name in the obstack gradually.
  63 When the name is complete, finalize it.  Then, if the symbol exists already,
  64 free the newly read name.
  65
  66 The way we do this is to take a large chunk, allocating memory from
  67 low addresses.  When you want to build a symbol in the chunk you just
  68 add chars above the current "high water mark" in the chunk.  When you
  69 have finished adding chars, because you got to the end of the symbol,
  70 you know how long the chars are, and you can create a new object.
  71 Mostly the chars will not burst over the highest address of the chunk,
  72 because you would typically expect a chunk to be (say) 100 times as
  73 long as an average object.
  74
  75 In case that isn't clear, when we have enough chars to make up
  76 the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed)
  77 so we just point to it where it lies.  No moving of chars is
  78 needed and this is the second win: potentially long strings need
  79 never be explicitly shuffled. Once an object is formed, it does not
  80 change its address during its lifetime.
  81
  82 When the chars burst over a chunk boundary, we allocate a larger
  83 chunk, and then copy the partly formed object from the end of the old
  84 chunk to the beginning of the new larger chunk.  We then carry on
  85 accreting characters to the end of the object as we normally would.
  86
  87 A special macro is provided to add a single char at a time to a
  88 growing object.  This allows the use of register variables, which
  89 break the ordinary 'growth' macro.
  90
  91 Summary:
  92         We allocate large chunks.
  93         We carve out one object at a time from the current chunk.
  94         Once carved, an object never moves.
  95         We are free to append data of any size to the currently
  96           growing object.
  97         Exactly one object is growing in an obstack at any one time.
  98         You can run one obstack per control block.
  99         You may have as many control blocks as you dare.
 100         Because of the way we do it, you can `unwind' an obstack
 101           back to a previous state. (You may remove objects much
 102           as you would with a stack.)
 103 */
 104
 105
 106 /* Don't do the contents of this file more than once.  */
 107
 108 #ifndef _OBSTACK_H
 109 #define _OBSTACK_H 1
 110
 111 #ifdef __cplusplus
 112 extern "C" {
 113 #endif
 114 \f
 115 /* We use subtraction of (char *) 0 instead of casting to int
 116    because on word-addressable machines a simple cast to int
 117    may ignore the byte-within-word field of the pointer.  */
 118
 119 #ifndef __PTR_TO_INT
 120 # define __PTR_TO_INT(P) ((P) - (char *) 0)
 121 #endif
 122
 123 #ifndef __INT_TO_PTR
 124 # define __INT_TO_PTR(P) ((P) + (char *) 0)
 125 #endif
 126
 127 /* We need the type of the resulting object.  If __PTRDIFF_TYPE__ is
 128    defined, as with GNU C, use that; that way we don't pollute the
 129    namespace with <stddef.h>'s symbols.  Otherwise, if <stddef.h> is
 130    available, include it and use ptrdiff_t.  In traditional C, long is
 131    the best that we can do.  */
 132
 133 #ifdef __PTRDIFF_TYPE__
 134 # define PTR_INT_TYPE __PTRDIFF_TYPE__
 135 #else
 136 # ifdef HAVE_STDDEF_H
 137 #  include <stddef.h>
 138 #  define PTR_INT_TYPE ptrdiff_t
 139 # else
 140 #  define PTR_INT_TYPE long
 141 # endif
 142 #endif
 143
 144 #if defined _LIBC || defined HAVE_STRING_H
 145 # include <string.h>
 146 # define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 147 #else
 148 # ifdef memcpy
 149 #  define _obstack_memcpy(To, From, N) memcpy ((To), (char *)(From), (N))
 150 # else
 151 #  define _obstack_memcpy(To, From, N) bcopy ((char *)(From), (To), (N))
 152 # endif
 153 #endif
 154
 155 struct _obstack_chunk           /* Lives at front of each chunk. */
 156 {
 157   char  *limit;                 /* 1 past end of this chunk */
 158   struct _obstack_chunk *prev;  /* address of prior chunk or NULL */
 159   char  contents[4];            /* objects begin here */
 160 };
 161
 162 struct obstack          /* control current object in current chunk */
 163 {
 164   long  chunk_size;             /* preferred size to allocate chunks in */
 165   struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */
 166   char  *object_base;           /* address of object we are building */
 167   char  *next_free;             /* where to add next char to current object */
 168   char  *chunk_limit;           /* address of char after current chunk */
 169   PTR_INT_TYPE temp;            /* Temporary for some macros.  */
 170   int   alignment_mask;         /* Mask of alignment for each object. */
 171   /* These prototypes vary based on `use_extra_arg', and we use
 172      casts to the prototypeless function type in all assignments,
 173      but having prototypes here quiets -Wstrict-prototypes.  */
 174   struct _obstack_chunk *(*chunkfun) (void *, long);
 175   void (*freefun) (void *, struct _obstack_chunk *);
 176   void *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 177   unsigned use_extra_arg:1;     /* chunk alloc/dealloc funcs take extra arg */
 178   unsigned maybe_empty_object:1;/* There is a possibility that the current
 179                                    chunk contains a zero-length object.  This
 180                                    prevents freeing the chunk if we allocate
 181                                    a bigger chunk to replace it. */
 182   unsigned alloc_failed:1;      /* No longer used, as we now call the failed
 183                                    handler on error, but retained for binary
 184                                    compatibility.  */
 185 };
 186
 187 /* Declare the external functions we use; they are in obstack.c.  */
 188
 189 extern void _obstack_newchunk (struct obstack *, int);
 190 extern void _obstack_free (struct obstack *, void *);
 191 extern int _obstack_begin (struct obstack *, int, int,
 192                             void *(*) (long), void (*) (void *));
 193 extern int _obstack_begin_1 (struct obstack *, int, int,
 194                              void *(*) (void *, long),
 195                              void (*) (void *, void *), void *);
 196 extern int _obstack_memory_used (struct obstack *);
 197 \f
 198 /* Do the function-declarations after the structs
 199    but before defining the macros.  */
 200
 201 void obstack_init (struct obstack *obstack);
 202
 203 void * obstack_alloc (struct obstack *obstack, int size);
 204
 205 void * obstack_copy (struct obstack *obstack, void *address, int size);
 206 void * obstack_copy0 (struct obstack *obstack, void *address, int size);
 207
 208 void obstack_free (struct obstack *obstack, void *block);
 209
 210 void obstack_blank (struct obstack *obstack, int size);
 211
 212 void obstack_grow (struct obstack *obstack, void *data, int size);
 213 void obstack_grow0 (struct obstack *obstack, void *data, int size);
 214
 215 void obstack_1grow (struct obstack *obstack, int data_char);
 216 void obstack_ptr_grow (struct obstack *obstack, void *data);
 217 void obstack_int_grow (struct obstack *obstack, int data);
 218
 219 void * obstack_finish (struct obstack *obstack);
 220
 221 int obstack_object_size (struct obstack *obstack);
 222
 223 int obstack_room (struct obstack *obstack);
 224 void obstack_make_room (struct obstack *obstack, int size);
 225 void obstack_1grow_fast (struct obstack *obstack, int data_char);
 226 void obstack_ptr_grow_fast (struct obstack *obstack, void *data);
 227 void obstack_int_grow_fast (struct obstack *obstack, int data);
 228 void obstack_blank_fast (struct obstack *obstack, int size);
 229
 230 void * obstack_base (struct obstack *obstack);
 231 void * obstack_next_free (struct obstack *obstack);
 232 int obstack_alignment_mask (struct obstack *obstack);
 233 int obstack_chunk_size (struct obstack *obstack);
 234 int obstack_memory_used (struct obstack *obstack);
 235
 236 /* Error handler called when `obstack_chunk_alloc' failed to allocate
 237    more memory.  This can be set to a user defined function.  The
 238    default action is to print a message and abort.  */
 239 extern void (*obstack_alloc_failed_handler) (void);
 240
 241 /* Exit value used when `print_and_abort' is used.  */
 242 extern int obstack_exit_failure;
 243 \f
 244 /* Pointer to beginning of object being allocated or to be allocated next.
 245    Note that this might not be the final address of the object
 246    because a new chunk might be needed to hold the final size.  */
 247
 248 #define obstack_base(h) ((h)->object_base)
 249
 250 /* Size for allocating ordinary chunks.  */
 251
 252 #define obstack_chunk_size(h) ((h)->chunk_size)
 253
 254 /* Pointer to next byte not yet allocated in current chunk.  */
 255
 256 #define obstack_next_free(h)    ((h)->next_free)
 257
 258 /* Mask specifying low bits that should be clear in address of an object.  */
 259
 260 #define obstack_alignment_mask(h) ((h)->alignment_mask)
 261
 262 /* To prevent prototype warnings provide complete argument list in
 263    standard C version.  */
 264 # define obstack_init(h) \
 265   _obstack_begin ((h), 0, 0, \
 266                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 267
 268 # define obstack_begin(h, size) \
 269   _obstack_begin ((h), (size), 0, \
 270                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 271
 272 # define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 273   _obstack_begin ((h), (size), (alignment), \
 274                     (void *(*) (long)) (chunkfun), (void (*) (void *)) (freefun))
 275
 276 # define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 277   _obstack_begin_1 ((h), (size), (alignment), \
 278                     (void *(*) (void *, long)) (chunkfun), \
 279                     (void (*) (void *, void *)) (freefun), (arg))
 280
 281 # define obstack_chunkfun(h, newchunkfun) \
 282   ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
 283
 284 # define obstack_freefun(h, newfreefun) \
 285   ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
 286
 287 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = (achar))
 288
 289 #define obstack_blank_fast(h,n) ((h)->next_free += (n))
 290
 291 #define obstack_memory_used(h) _obstack_memory_used (h)
 292 \f
 293 #if defined __GNUC__ && defined __STDC__ && __STDC__
 294 /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and
 295    does not implement __extension__.  But that compiler doesn't define
 296    __GNUC_MINOR__.  */
 297 # if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__)
 298 #  define __extension__
 299 # endif
 300
 301 /* For GNU C, if not -traditional,
 302    we can define these macros to compute all args only once
 303    without using a global variable.
 304    Also, we can avoid using the `temp' slot, to make faster code.  */
 305
 306 # define obstack_object_size(OBSTACK)                                   \
 307   __extension__                                                         \
 308   ({ struct obstack *__o = (OBSTACK);                                   \
 309      (unsigned) (__o->next_free - __o->object_base); })
 310
 311 # define obstack_room(OBSTACK)                                          \
 312   __extension__                                                         \
 313   ({ struct obstack *__o = (OBSTACK);                                   \
 314      (unsigned) (__o->chunk_limit - __o->next_free); })
 315
 316 # define obstack_make_room(OBSTACK,length)                              \
 317 __extension__                                                           \
 318 ({ struct obstack *__o = (OBSTACK);                                     \
 319    int __len = (length);                                                \
 320    if (__o->chunk_limit - __o->next_free < __len)                       \
 321      _obstack_newchunk (__o, __len);                                    \
 322    (void) 0; })
 323
 324 # define obstack_empty_p(OBSTACK)                                       \
 325   __extension__                                                         \
 326   ({ struct obstack *__o = (OBSTACK);                                   \
 327      (__o->chunk->prev == 0 && __o->next_free - __o->chunk->contents == 0); })
 328
 329 # define obstack_grow(OBSTACK,where,length)                             \
 330 __extension__                                                           \
 331 ({ struct obstack *__o = (OBSTACK);                                     \
 332    int __len = (length);                                                \
 333    if (__o->next_free + __len > __o->chunk_limit)                       \
 334      _obstack_newchunk (__o, __len);                                    \
 335    _obstack_memcpy (__o->next_free, (where), __len);                    \
 336    __o->next_free += __len;                                             \
 337    (void) 0; })
 338
 339 # define obstack_grow0(OBSTACK,where,length)                            \
 340 __extension__                                                           \
 341 ({ struct obstack *__o = (OBSTACK);                                     \
 342    int __len = (length);                                                \
 343    if (__o->next_free + __len + 1 > __o->chunk_limit)                   \
 344      _obstack_newchunk (__o, __len + 1);                                \
 345    _obstack_memcpy (__o->next_free, (where), __len);                    \
 346    __o->next_free += __len;                                             \
 347    *(__o->next_free)++ = 0;                                             \
 348    (void) 0; })
 349
 350 # define obstack_1grow(OBSTACK,datum)                                   \
 351 __extension__                                                           \
 352 ({ struct obstack *__o = (OBSTACK);                                     \
 353    if (__o->next_free + 1 > __o->chunk_limit)                           \
 354      _obstack_newchunk (__o, 1);                                        \
 355    obstack_1grow_fast (__o, datum);                                     \
 356    (void) 0; })
 357
 358 /* These assume that the obstack alignment is good enough for pointers or ints,
 359    and that the data added so far to the current object
 360    shares that much alignment.  */
 361
 362 # define obstack_ptr_grow(OBSTACK,datum)                                \
 363 __extension__                                                           \
 364 ({ struct obstack *__o = (OBSTACK);                                     \
 365    if (__o->next_free + sizeof (void *) > __o->chunk_limit)             \
 366      _obstack_newchunk (__o, sizeof (void *));                          \
 367    obstack_ptr_grow_fast (__o, datum); })
 368
 369 # define obstack_int_grow(OBSTACK,datum)                                \
 370 __extension__                                                           \
 371 ({ struct obstack *__o = (OBSTACK);                                     \
 372    if (__o->next_free + sizeof (int) > __o->chunk_limit)                \
 373      _obstack_newchunk (__o, sizeof (int));                             \
 374    obstack_int_grow_fast (__o, datum); })
 375
 376 # define obstack_ptr_grow_fast(OBSTACK,aptr)                            \
 377 __extension__                                                           \
 378 ({ struct obstack *__o1 = (OBSTACK);                                    \
 379    *(const void **) __o1->next_free = (aptr);                           \
 380    __o1->next_free += sizeof (const void *);                            \
 381    (void) 0; })
 382
 383 # define obstack_int_grow_fast(OBSTACK,aint)                            \
 384 __extension__                                                           \
 385 ({ struct obstack *__o1 = (OBSTACK);                                    \
 386    *(int *) __o1->next_free = (aint);                                   \
 387    __o1->next_free += sizeof (int);                                     \
 388    (void) 0; })
 389
 390 # define obstack_blank(OBSTACK,length)                                  \
 391 __extension__                                                           \
 392 ({ struct obstack *__o = (OBSTACK);                                     \
 393    int __len = (length);                                                \
 394    if (__o->chunk_limit - __o->next_free < __len)                       \
 395      _obstack_newchunk (__o, __len);                                    \
 396    obstack_blank_fast (__o, __len);                                     \
 397    (void) 0; })
 398
 399 # define obstack_alloc(OBSTACK,length)                                  \
 400 __extension__                                                           \
 401 ({ struct obstack *__h = (OBSTACK);                                     \
 402    obstack_blank (__h, (length));                                       \
 403    obstack_finish (__h); })
 404
 405 # define obstack_copy(OBSTACK,where,length)                             \
 406 __extension__                                                           \
 407 ({ struct obstack *__h = (OBSTACK);                                     \
 408    obstack_grow (__h, (where), (length));                               \
 409    obstack_finish (__h); })
 410
 411 # define obstack_copy0(OBSTACK,where,length)                            \
 412 __extension__                                                           \
 413 ({ struct obstack *__h = (OBSTACK);                                     \
 414    obstack_grow0 (__h, (where), (length));                              \
 415    obstack_finish (__h); })
 416
 417 /* The local variable is named __o1 to avoid a name conflict
 418    when obstack_blank is called.  */
 419 # define obstack_finish(OBSTACK)                                        \
 420 __extension__                                                           \
 421 ({ struct obstack *__o1 = (OBSTACK);                                    \
 422    void *value;                                                         \
 423    value = (void *) __o1->object_base;                                  \
 424    if (__o1->next_free == value)                                        \
 425      __o1->maybe_empty_object = 1;                                      \
 426    __o1->next_free                                                      \
 427      = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\
 428                      & ~ (__o1->alignment_mask));                       \
 429    if (__o1->next_free - (char *)__o1->chunk                            \
 430        > __o1->chunk_limit - (char *)__o1->chunk)                       \
 431      __o1->next_free = __o1->chunk_limit;                               \
 432    __o1->object_base = __o1->next_free;                                 \
 433    value; })
 434
 435 # define obstack_free(OBSTACK, OBJ)                                     \
 436 __extension__                                                           \
 437 ({ struct obstack *__o = (OBSTACK);                                     \
 438    void *__obj = (void *) (OBJ);                                        \
 439    if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit)  \
 440      __o->next_free = __o->object_base = (char *) __obj;                \
 441    else (obstack_free) (__o, __obj); })
 442 \f
 443 #else /* not __GNUC__ or not __STDC__ */
 444
 445 # define obstack_object_size(h) \
 446  (unsigned) ((h)->next_free - (h)->object_base)
 447
 448 # define obstack_room(h)                \
 449  (unsigned) ((h)->chunk_limit - (h)->next_free)
 450
 451 # define obstack_empty_p(h) \
 452  ((h)->chunk->prev == 0 && (h)->next_free - (h)->chunk->contents == 0)
 453
 454 /* Note that the call to _obstack_newchunk is enclosed in (..., 0)
 455    so that we can avoid having void expressions
 456    in the arms of the conditional expression.
 457    Casting the third operand to void was tried before,
 458    but some compilers won't accept it.  */
 459
 460 # define obstack_make_room(h,length)                                    \
 461 ( (h)->temp = (length),                                                 \
 462   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 463    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0))
 464
 465 # define obstack_grow(h,where,length)                                   \
 466 ( (h)->temp = (length),                                                 \
 467   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 468    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 469   _obstack_memcpy ((h)->next_free, (where), (h)->temp),                 \
 470   (h)->next_free += (h)->temp)
 471
 472 # define obstack_grow0(h,where,length)                                  \
 473 ( (h)->temp = (length),                                                 \
 474   (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit)                  \
 475    ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0),                  \
 476   _obstack_memcpy ((h)->next_free, (where), (h)->temp),                 \
 477   (h)->next_free += (h)->temp,                                          \
 478   *((h)->next_free)++ = 0)
 479
 480 # define obstack_1grow(h,datum)                                         \
 481 ( (((h)->next_free + 1 > (h)->chunk_limit)                              \
 482    ? (_obstack_newchunk ((h), 1), 0) : 0),                              \
 483   obstack_1grow_fast (h, datum))
 484
 485 # define obstack_ptr_grow(h,datum)                                      \
 486 ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit)                \
 487    ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0),                \
 488   obstack_ptr_grow_fast (h, datum))
 489
 490 # define obstack_int_grow(h,datum)                                      \
 491 ( (((h)->next_free + sizeof (int) > (h)->chunk_limit)                   \
 492    ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0),                   \
 493   obstack_int_grow_fast (h, datum))
 494
 495 # define obstack_ptr_grow_fast(h,aptr)                                  \
 496   (((const void **) ((h)->next_free += sizeof (void *)))[-1] = (aptr))
 497
 498 # define obstack_int_grow_fast(h,aint)                                  \
 499   (((int *) ((h)->next_free += sizeof (int)))[-1] = (aptr))
 500
 501 # define obstack_blank(h,length)                                        \
 502 ( (h)->temp = (length),                                                 \
 503   (((h)->chunk_limit - (h)->next_free < (h)->temp)                      \
 504    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 505   obstack_blank_fast (h, (h)->temp))
 506
 507 # define obstack_alloc(h,length)                                        \
 508  (obstack_blank ((h), (length)), obstack_finish ((h)))
 509
 510 # define obstack_copy(h,where,length)                                   \
 511  (obstack_grow ((h), (where), (length)), obstack_finish ((h)))
 512
 513 # define obstack_copy0(h,where,length)                                  \
 514  (obstack_grow0 ((h), (where), (length)), obstack_finish ((h)))
 515
 516 # define obstack_finish(h)                                              \
 517 ( ((h)->next_free == (h)->object_base                                   \
 518    ? (((h)->maybe_empty_object = 1), 0)                                 \
 519    : 0),                                                                \
 520   (h)->temp = __PTR_TO_INT ((h)->object_base),                          \
 521   (h)->next_free                                                        \
 522     = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \
 523                     & ~ ((h)->alignment_mask)),                         \
 524   (((h)->next_free - (char *) (h)->chunk                                \
 525     > (h)->chunk_limit - (char *) (h)->chunk)                           \
 526    ? ((h)->next_free = (h)->chunk_limit) : 0),                          \
 527   (h)->object_base = (h)->next_free,                                    \
 528   (void *) __INT_TO_PTR ((h)->temp))
 529
 530 # define obstack_free(h,obj)                                            \
 531 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 532   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 533    ? (((h)->next_free = (h)->object_base                                \
 534             = (h)->temp + (char *) (h)->chunk), 0)                      \
 535    : ((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0)))
 536
 537 #endif /* not __GNUC__ or not __STDC__ */
 538
 539 #ifdef __cplusplus
 540 }       /* C++ */
 541 #endif
 542
 543 #endif /* obstack.h */