gcc/obstack.h

   1 /* obstack.h - object stack macros
   2    Copyright (C) 1988,89,90,91,92,93,94,96 Free Software Foundation, Inc.
   3
   4 This program is free software; you can redistribute it and/or modify it
   5 under the terms of the GNU General Public License as published by the
   6 Free Software Foundation; either version 2, or (at your option) any
   7 later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 /* Summary:
  19
  20 All the apparent functions defined here are macros. The idea
  21 is that you would use these pre-tested macros to solve a
  22 very specific set of problems, and they would run fast.
  23 Caution: no side-effects in arguments please!! They may be
  24 evaluated MANY times!!
  25
  26 These macros operate a stack of objects.  Each object starts life
  27 small, and may grow to maturity.  (Consider building a word syllable
  28 by syllable.)  An object can move while it is growing.  Once it has
  29 been "finished" it never changes address again.  So the "top of the
  30 stack" is typically an immature growing object, while the rest of the
  31 stack is of mature, fixed size and fixed address objects.
  32
  33 These routines grab large chunks of memory, using a function you
  34 supply, called `obstack_chunk_alloc'.  On occasion, they free chunks,
  35 by calling `obstack_chunk_free'.  You must define them and declare
  36 them before using any obstack macros.
  37
  38 Each independent stack is represented by a `struct obstack'.
  39 Each of the obstack macros expects a pointer to such a structure
  40 as the first argument.
  41
  42 One motivation for this package is the problem of growing char strings
  43 in symbol tables.  Unless you are "fascist pig with a read-only mind"
  44 --Gosper's immortal quote from HAKMEM item 154, out of context--you
  45 would not like to put any arbitrary upper limit on the length of your
  46 symbols.
  47
  48 In practice this often means you will build many short symbols and a
  49 few long symbols.  At the time you are reading a symbol you don't know
  50 how long it is.  One traditional method is to read a symbol into a
  51 buffer, realloc()ating the buffer every time you try to read a symbol
  52 that is longer than the buffer.  This is beaut, but you still will
  53 want to copy the symbol from the buffer to a more permanent
  54 symbol-table entry say about half the time.
  55
  56 With obstacks, you can work differently.  Use one obstack for all symbol
  57 names.  As you read a symbol, grow the name in the obstack gradually.
  58 When the name is complete, finalize it.  Then, if the symbol exists already,
  59 free the newly read name.
  60
  61 The way we do this is to take a large chunk, allocating memory from
  62 low addresses.  When you want to build a symbol in the chunk you just
  63 add chars above the current "high water mark" in the chunk.  When you
  64 have finished adding chars, because you got to the end of the symbol,
  65 you know how long the chars are, and you can create a new object.
  66 Mostly the chars will not burst over the highest address of the chunk,
  67 because you would typically expect a chunk to be (say) 100 times as
  68 long as an average object.
  69
  70 In case that isn't clear, when we have enough chars to make up
  71 the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed)
  72 so we just point to it where it lies.  No moving of chars is
  73 needed and this is the second win: potentially long strings need
  74 never be explicitly shuffled. Once an object is formed, it does not
  75 change its address during its lifetime.
  76
  77 When the chars burst over a chunk boundary, we allocate a larger
  78 chunk, and then copy the partly formed object from the end of the old
  79 chunk to the beginning of the new larger chunk.  We then carry on
  80 accreting characters to the end of the object as we normally would.
  81
  82 A special macro is provided to add a single char at a time to a
  83 growing object.  This allows the use of register variables, which
  84 break the ordinary 'growth' macro.
  85
  86 Summary:
  87         We allocate large chunks.
  88         We carve out one object at a time from the current chunk.
  89         Once carved, an object never moves.
  90         We are free to append data of any size to the currently
  91           growing object.
  92         Exactly one object is growing in an obstack at any one time.
  93         You can run one obstack per control block.
  94         You may have as many control blocks as you dare.
  95         Because of the way we do it, you can `unwind' an obstack
  96           back to a previous state. (You may remove objects much
  97           as you would with a stack.)
  98 */
  99
 100
 101 /* Don't do the contents of this file more than once.  */
 102
 103 #ifndef __OBSTACK_H__
 104 #define __OBSTACK_H__
 105 \f
 106 /* We use subtraction of (char *) 0 instead of casting to int
 107    because on word-addressable machines a simple cast to int
 108    may ignore the byte-within-word field of the pointer.  */
 109
 110 #ifndef __PTR_TO_INT
 111 #define __PTR_TO_INT(P) ((P) - (char *) 0)
 112 #endif
 113
 114 #ifndef __INT_TO_PTR
 115 #define __INT_TO_PTR(P) ((P) + (char *) 0)
 116 #endif
 117
 118 /* We need the type of the resulting object.  In ANSI C it is ptrdiff_t
 119    but in traditional C it is usually long.  If we are in ANSI C and
 120    don't already have ptrdiff_t get it.  */
 121
 122 #if defined (__STDC__) && __STDC__ && ! defined (offsetof)
 123 #if defined (__GNUC__) && defined (IN_GCC)
 124 /* On Next machine, the system's stddef.h screws up if included
 125    after we have defined just ptrdiff_t, so include all of stddef.h.
 126    Otherwise, define just ptrdiff_t, which is all we need.  */
 127 #ifndef __NeXT__
 128 #define __need_ptrdiff_t
 129 #endif
 130 #endif
 131
 132 #include <stddef.h>
 133 #endif
 134
 135 #if defined (__STDC__) && __STDC__
 136 #define PTR_INT_TYPE ptrdiff_t
 137 #else
 138 #define PTR_INT_TYPE long
 139 #endif
 140
 141 struct _obstack_chunk           /* Lives at front of each chunk. */
 142 {
 143   char  *limit;                 /* 1 past end of this chunk */
 144   struct _obstack_chunk *prev;  /* address of prior chunk or NULL */
 145   char  contents[4];            /* objects begin here */
 146 };
 147
 148 struct obstack          /* control current object in current chunk */
 149 {
 150   long  chunk_size;             /* preferred size to allocate chunks in */
 151   struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */
 152   char  *object_base;           /* address of object we are building */
 153   char  *next_free;             /* where to add next char to current object */
 154   char  *chunk_limit;           /* address of char after current chunk */
 155   PTR_INT_TYPE temp;            /* Temporary for some macros.  */
 156   int   alignment_mask;         /* Mask of alignment for each object. */
 157 #if defined (__STDC__) && __STDC__
 158   /* These prototypes vary based on `use_extra_arg', and we use
 159      casts to the prototypeless function type in all assignments,
 160      but having prototypes here quiets -Wstrict-prototypes.  */
 161   struct _obstack_chunk *(*chunkfun) (void *, long);
 162   void (*freefun) (void *, struct _obstack_chunk *);
 163   void *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 164 #else
 165   struct _obstack_chunk *(*chunkfun) (); /* User's fcn to allocate a chunk.  */
 166   void (*freefun) ();           /* User's function to free a chunk.  */
 167   char *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 168 #endif
 169   unsigned use_extra_arg:1;     /* chunk alloc/dealloc funcs take extra arg */
 170   unsigned maybe_empty_object:1;/* There is a possibility that the current
 171                                    chunk contains a zero-length object.  This
 172                                    prevents freeing the chunk if we allocate
 173                                    a bigger chunk to replace it. */
 174   unsigned alloc_failed:1;      /* chunk alloc func returned 0 */
 175 };
 176
 177 /* Declare the external functions we use; they are in obstack.c.  */
 178
 179 #if defined (__STDC__) && __STDC__
 180 extern void _obstack_newchunk (struct obstack *, int);
 181 extern void _obstack_free (struct obstack *, void *);
 182 extern int _obstack_begin (struct obstack *, int, int,
 183                             void *(*) (long), void (*) (void *));
 184 extern int _obstack_begin_1 (struct obstack *, int, int,
 185                              void *(*) (void *, long),
 186                              void (*) (void *, void *), void *);
 187 #else
 188 extern void _obstack_newchunk ();
 189 extern void _obstack_free ();
 190 extern int _obstack_begin ();
 191 extern int _obstack_begin_1 ();
 192 #endif
 193 \f
 194 #if defined (__STDC__) && __STDC__
 195
 196 /* Do the function-declarations after the structs
 197    but before defining the macros.  */
 198
 199 void obstack_init (struct obstack *obstack);
 200
 201 void * obstack_alloc (struct obstack *obstack, int size);
 202
 203 void * obstack_copy (struct obstack *obstack, void *address, int size);
 204 void * obstack_copy0 (struct obstack *obstack, void *address, int size);
 205
 206 void obstack_free (struct obstack *obstack, void *block);
 207
 208 void obstack_blank (struct obstack *obstack, int size);
 209
 210 void obstack_grow (struct obstack *obstack, void *data, int size);
 211 void obstack_grow0 (struct obstack *obstack, void *data, int size);
 212
 213 void obstack_1grow (struct obstack *obstack, int data_char);
 214 void obstack_ptr_grow (struct obstack *obstack, void *data);
 215 void obstack_int_grow (struct obstack *obstack, int data);
 216
 217 void * obstack_finish (struct obstack *obstack);
 218
 219 int obstack_object_size (struct obstack *obstack);
 220
 221 int obstack_room (struct obstack *obstack);
 222 void obstack_1grow_fast (struct obstack *obstack, int data_char);
 223 void obstack_ptr_grow_fast (struct obstack *obstack, void *data);
 224 void obstack_int_grow_fast (struct obstack *obstack, int data);
 225 void obstack_blank_fast (struct obstack *obstack, int size);
 226
 227 void * obstack_base (struct obstack *obstack);
 228 void * obstack_next_free (struct obstack *obstack);
 229 int obstack_alignment_mask (struct obstack *obstack);
 230 int obstack_chunk_size (struct obstack *obstack);
 231
 232 #endif /* __STDC__ */
 233
 234 /* Non-ANSI C cannot really support alternative functions for these macros,
 235    so we do not declare them.  */
 236 \f
 237 /* Pointer to beginning of object being allocated or to be allocated next.
 238    Note that this might not be the final address of the object
 239    because a new chunk might be needed to hold the final size.  */
 240
 241 #define obstack_base(h) ((h)->alloc_failed ? 0 : (h)->object_base)
 242
 243 /* Size for allocating ordinary chunks.  */
 244
 245 #define obstack_chunk_size(h) ((h)->chunk_size)
 246
 247 /* Pointer to next byte not yet allocated in current chunk.  */
 248
 249 #define obstack_next_free(h)    ((h)->alloc_failed ? 0 : (h)->next_free)
 250
 251 /* Mask specifying low bits that should be clear in address of an object.  */
 252
 253 #define obstack_alignment_mask(h) ((h)->alignment_mask)
 254
 255 /* To prevent prototype warnings provide complete argument list in
 256    standard C version.  */
 257 #if defined (__STDC__) && __STDC__
 258
 259 #define obstack_init(h) \
 260   _obstack_begin ((h), 0, 0, \
 261                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 262
 263 #define obstack_begin(h, size) \
 264   _obstack_begin ((h), (size), 0, \
 265                   (void *(*) (long)) obstack_chunk_alloc, (void (*) (void *)) obstack_chunk_free)
 266
 267 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 268   _obstack_begin ((h), (size), (alignment), \
 269                     (void *(*) (long)) (chunkfun), (void (*) (void *)) (freefun))
 270
 271 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 272   _obstack_begin_1 ((h), (size), (alignment), \
 273                     (void *(*) (long)) (chunkfun), (void (*) (void *)) (freefun), (arg))
 274
 275 #define obstack_chunkfun(h, newchunkfun) \
 276   ((h) -> chunkfun = (struct _obstack_chunk *(*)(long)) (newchunkfun))
 277
 278 #define obstack_freefun(h, newfreefun) \
 279   ((h) -> freefun = (void (*)(void *)) (newfreefun))
 280
 281 #else
 282
 283 #define obstack_init(h) \
 284   _obstack_begin ((h), 0, 0, \
 285                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 286
 287 #define obstack_begin(h, size) \
 288   _obstack_begin ((h), (size), 0, \
 289                   (void *(*) ()) obstack_chunk_alloc, (void (*) ()) obstack_chunk_free)
 290
 291 #define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 292   _obstack_begin ((h), (size), (alignment), \
 293                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun))
 294
 295 #define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 296   _obstack_begin_1 ((h), (size), (alignment), \
 297                     (void *(*) ()) (chunkfun), (void (*) ()) (freefun), (arg))
 298
 299 #define obstack_chunkfun(h, newchunkfun) \
 300   ((h) -> chunkfun = (struct _obstack_chunk *(*)()) (newchunkfun))
 301
 302 #define obstack_freefun(h, newfreefun) \
 303   ((h) -> freefun = (void (*)()) (newfreefun))
 304
 305 #endif
 306
 307 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = achar)
 308
 309 #define obstack_blank_fast(h,n) ((h)->next_free += (n))
 310 \f
 311 #if defined (__GNUC__) && defined (__STDC__) && __STDC__
 312 /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and
 313    does not implement __extension__.  But that compiler doesn't define
 314    __GNUC_MINOR__.  */
 315 #if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__)
 316 #define __extension__
 317 #endif
 318
 319 /* For GNU C, if not -traditional,
 320    we can define these macros to compute all args only once
 321    without using a global variable.
 322    Also, we can avoid using the `temp' slot, to make faster code.  */
 323
 324 #define obstack_object_size(OBSTACK)                                    \
 325   __extension__                                                         \
 326   ({ struct obstack *__o = (OBSTACK);                                   \
 327      __o->alloc_failed ? 0 :                                            \
 328      (unsigned) (__o->next_free - __o->object_base); })
 329
 330 #define obstack_room(OBSTACK)                                           \
 331   __extension__                                                         \
 332   ({ struct obstack *__o = (OBSTACK);                                   \
 333      (unsigned) (__o->chunk_limit - __o->next_free); })
 334
 335 #define obstack_grow(OBSTACK,where,length)                              \
 336 __extension__                                                           \
 337 ({ struct obstack *__o = (OBSTACK);                                     \
 338    int __len = (length);                                                \
 339    if (__o->next_free + __len > __o->chunk_limit)                       \
 340      _obstack_newchunk (__o, __len);                                    \
 341    if (!__o->alloc_failed)                                              \
 342      {                                                                  \
 343         bcopy ((char *) (where), __o->next_free, __len);                \
 344         __o->next_free += __len;                                        \
 345      }                                                                  \
 346    (void) 0; })
 347
 348 #define obstack_grow0(OBSTACK,where,length)                             \
 349 __extension__                                                           \
 350 ({ struct obstack *__o = (OBSTACK);                                     \
 351    int __len = (length);                                                \
 352    if (__o->next_free + __len + 1 > __o->chunk_limit)                   \
 353      _obstack_newchunk (__o, __len + 1);                                \
 354    if (!__o->alloc_failed)                                              \
 355      {                                                                  \
 356        bcopy ((char *) (where), __o->next_free, __len);                 \
 357        __o->next_free += __len;                                         \
 358        *(__o->next_free)++ = 0;                                         \
 359      }                                                                  \
 360    (void) 0; })
 361
 362 #define obstack_1grow(OBSTACK,datum)                                    \
 363 __extension__                                                           \
 364 ({ struct obstack *__o = (OBSTACK);                                     \
 365    if (__o->next_free + 1 > __o->chunk_limit)                           \
 366      _obstack_newchunk (__o, 1);                                        \
 367    if (!__o->alloc_failed)                                              \
 368      *(__o->next_free)++ = (datum);                                     \
 369    (void) 0; })
 370
 371 /* These assume that the obstack alignment is good enough for pointers or ints,
 372    and that the data added so far to the current object
 373    shares that much alignment.  */
 374
 375 #define obstack_ptr_grow(OBSTACK,datum)                                 \
 376 __extension__                                                           \
 377 ({ struct obstack *__o = (OBSTACK);                                     \
 378    if (__o->next_free + sizeof (void *) > __o->chunk_limit)             \
 379      _obstack_newchunk (__o, sizeof (void *));                          \
 380    if (!__o->alloc_failed)                                              \
 381      *((void **)__o->next_free)++ = ((void *)datum);                    \
 382    (void) 0; })
 383
 384 #define obstack_int_grow(OBSTACK,datum)                                 \
 385 __extension__                                                           \
 386 ({ struct obstack *__o = (OBSTACK);                                     \
 387    if (__o->next_free + sizeof (int) > __o->chunk_limit)                \
 388      _obstack_newchunk (__o, sizeof (int));                             \
 389    if (!__o->alloc_failed)                                              \
 390      *((int *)__o->next_free)++ = ((int)datum);                         \
 391    (void) 0; })
 392
 393 #define obstack_ptr_grow_fast(h,aptr) (*((void **) (h)->next_free)++ = (void *)aptr)
 394 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 395
 396 #define obstack_blank(OBSTACK,length)                                   \
 397 __extension__                                                           \
 398 ({ struct obstack *__o = (OBSTACK);                                     \
 399    int __len = (length);                                                \
 400    if (__o->chunk_limit - __o->next_free < __len)                       \
 401      _obstack_newchunk (__o, __len);                                    \
 402    if (!__o->alloc_failed)                                              \
 403      __o->next_free += __len;                                           \
 404    (void) 0; })
 405
 406 #define obstack_alloc(OBSTACK,length)                                   \
 407 __extension__                                                           \
 408 ({ struct obstack *__h = (OBSTACK);                                     \
 409    obstack_blank (__h, (length));                                       \
 410    obstack_finish (__h); })
 411
 412 #define obstack_copy(OBSTACK,where,length)                              \
 413 __extension__                                                           \
 414 ({ struct obstack *__h = (OBSTACK);                                     \
 415    obstack_grow (__h, (where), (length));                               \
 416    obstack_finish (__h); })
 417
 418 #define obstack_copy0(OBSTACK,where,length)                             \
 419 __extension__                                                           \
 420 ({ struct obstack *__h = (OBSTACK);                                     \
 421    obstack_grow0 (__h, (where), (length));                              \
 422    obstack_finish (__h); })
 423
 424 /* The local variable is named __o1 to avoid a name conflict
 425    when obstack_blank is called.  */
 426 #define obstack_finish(OBSTACK)                                         \
 427 __extension__                                                           \
 428 ({ struct obstack *__o1 = (OBSTACK);                                    \
 429    void *value;                                                         \
 430    if (__o1->alloc_failed)                                              \
 431      value = 0;                                                         \
 432    else                                                                 \
 433      {                                                                  \
 434        value = (void *) __o1->object_base;                              \
 435        if (__o1->next_free == value)                                    \
 436          __o1->maybe_empty_object = 1;                                  \
 437        __o1->next_free                                                  \
 438          = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\
 439                          & ~ (__o1->alignment_mask));                   \
 440        if (__o1->next_free - (char *)__o1->chunk                        \
 441            > __o1->chunk_limit - (char *)__o1->chunk)                   \
 442          __o1->next_free = __o1->chunk_limit;                           \
 443        __o1->object_base = __o1->next_free;                             \
 444       }                                                                 \
 445    value; })
 446
 447 #define obstack_free(OBSTACK, OBJ)                                      \
 448 __extension__                                                           \
 449 ({ struct obstack *__o = (OBSTACK);                                     \
 450    void *__obj = (OBJ);                                                 \
 451    if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit)  \
 452      __o->next_free = __o->object_base = __obj;                         \
 453    else (obstack_free) (__o, __obj); })
 454 \f
 455 #else /* not __GNUC__ or not __STDC__ */
 456
 457 #define obstack_object_size(h) \
 458  (unsigned) ((h)->alloc_failed ? 0 : (h)->next_free - (h)->object_base)
 459
 460 #define obstack_room(h)         \
 461  (unsigned) ((h)->chunk_limit - (h)->next_free)
 462
 463 /* Note that the call to _obstack_newchunk is enclosed in (..., 0)
 464    so that we can avoid having void expressions
 465    in the arms of the conditional expression.
 466    Casting the third operand to void was tried before,
 467    but some compilers won't accept it.  */
 468
 469 #define obstack_grow(h,where,length)                                    \
 470 ( (h)->temp = (length),                                                 \
 471   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 472    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 473   ((h)->alloc_failed ? 0 :                                              \
 474   (bcopy ((char *) (where), (h)->next_free, (h)->temp),                 \
 475   (h)->next_free += (h)->temp)))
 476
 477 #define obstack_grow0(h,where,length)                                   \
 478 ( (h)->temp = (length),                                                 \
 479   (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit)                  \
 480    ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0),                  \
 481   ((h)->alloc_failed ? 0 :                                              \
 482   (bcopy ((char *) (where), (h)->next_free, (h)->temp),                 \
 483   (h)->next_free += (h)->temp,                                          \
 484   *((h)->next_free)++ = 0)))
 485
 486 #define obstack_1grow(h,datum)                                          \
 487 ( (((h)->next_free + 1 > (h)->chunk_limit)                              \
 488    ? (_obstack_newchunk ((h), 1), 0) : 0),                              \
 489  ((h)->alloc_failed ? 0 :                                               \
 490   (*((h)->next_free)++ = (datum))))
 491
 492 #define obstack_ptr_grow(h,datum)                                       \
 493 ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit)                \
 494    ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0),                \
 495   ((h)->alloc_failed ? 0 :                                              \
 496   (*((char **) (((h)->next_free+=sizeof(char *))-sizeof(char *))) = ((char *) datum))))
 497
 498 #define obstack_int_grow(h,datum)                                       \
 499 ( (((h)->next_free + sizeof (int) > (h)->chunk_limit)                   \
 500    ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0),                   \
 501   ((h)->alloc_failed ? 0 :                                              \
 502   (*((int *) (((h)->next_free+=sizeof(int))-sizeof(int))) = ((int) datum))))
 503
 504 #define obstack_ptr_grow_fast(h,aptr) (*((char **) (h)->next_free)++ = (char *) aptr)
 505 #define obstack_int_grow_fast(h,aint) (*((int *) (h)->next_free)++ = (int) aint)
 506
 507 #define obstack_blank(h,length)                                         \
 508 ( (h)->temp = (length),                                                 \
 509   (((h)->chunk_limit - (h)->next_free < (h)->temp)                      \
 510    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 511   ((h)->alloc_failed ? 0 :                                              \
 512   ((h)->next_free += (h)->temp)))
 513
 514 #define obstack_alloc(h,length)                                         \
 515  (obstack_blank ((h), (length)), obstack_finish ((h)))
 516
 517 #define obstack_copy(h,where,length)                                    \
 518  (obstack_grow ((h), (where), (length)), obstack_finish ((h)))
 519
 520 #define obstack_copy0(h,where,length)                                   \
 521  (obstack_grow0 ((h), (where), (length)), obstack_finish ((h)))
 522
 523 #define obstack_finish(h)                                               \
 524 ( (h)->alloc_failed ? 0 :                                               \
 525   (((h)->next_free == (h)->object_base                                  \
 526    ? (((h)->maybe_empty_object = 1), 0)                                 \
 527    : 0),                                                                \
 528   (h)->temp = __PTR_TO_INT ((h)->object_base),                          \
 529   (h)->next_free                                                        \
 530     = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \
 531                     & ~ ((h)->alignment_mask)),                         \
 532   (((h)->next_free - (char *) (h)->chunk                                        \
 533     > (h)->chunk_limit - (char *) (h)->chunk)                           \
 534    ? ((h)->next_free = (h)->chunk_limit) : 0),                          \
 535   (h)->object_base = (h)->next_free,                                    \
 536   __INT_TO_PTR ((h)->temp)))
 537
 538 #if defined (__STDC__) && __STDC__
 539 #define obstack_free(h,obj)                                             \
 540 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 541   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 542    ? (int) ((h)->next_free = (h)->object_base                           \
 543             = (h)->temp + (char *) (h)->chunk)                          \
 544    : (((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0), 0)))
 545 #else
 546 #define obstack_free(h,obj)                                             \
 547 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 548   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 549    ? (int) ((h)->next_free = (h)->object_base                           \
 550             = (h)->temp + (char *) (h)->chunk)                          \
 551    : (_obstack_free ((h), (h)->temp + (char *) (h)->chunk), 0)))
 552 #endif
 553
 554 #endif /* not __GNUC__ or not __STDC__ */
 555
 556 #endif /* not __OBSTACK_H__ */