malloc/obstack.h

   1 /* obstack.h - object stack macros
   2    Copyright (C) 1988,89,90,91,92,93,94,96,97,98,99 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.  Its master source is NOT part of
   4    the C library, however.  The master source lives in /gd/gnu/lib.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 /* Summary:
  22
  23 All the apparent functions defined here are macros. The idea
  24 is that you would use these pre-tested macros to solve a
  25 very specific set of problems, and they would run fast.
  26 Caution: no side-effects in arguments please!! They may be
  27 evaluated MANY times!!
  28
  29 These macros operate a stack of objects.  Each object starts life
  30 small, and may grow to maturity.  (Consider building a word syllable
  31 by syllable.)  An object can move while it is growing.  Once it has
  32 been "finished" it never changes address again.  So the "top of the
  33 stack" is typically an immature growing object, while the rest of the
  34 stack is of mature, fixed size and fixed address objects.
  35
  36 These routines grab large chunks of memory, using a function you
  37 supply, called `obstack_chunk_alloc'.  On occasion, they free chunks,
  38 by calling `obstack_chunk_free'.  You must define them and declare
  39 them before using any obstack macros.
  40
  41 Each independent stack is represented by a `struct obstack'.
  42 Each of the obstack macros expects a pointer to such a structure
  43 as the first argument.
  44
  45 One motivation for this package is the problem of growing char strings
  46 in symbol tables.  Unless you are "fascist pig with a read-only mind"
  47 --Gosper's immortal quote from HAKMEM item 154, out of context--you
  48 would not like to put any arbitrary upper limit on the length of your
  49 symbols.
  50
  51 In practice this often means you will build many short symbols and a
  52 few long symbols.  At the time you are reading a symbol you don't know
  53 how long it is.  One traditional method is to read a symbol into a
  54 buffer, realloc()ating the buffer every time you try to read a symbol
  55 that is longer than the buffer.  This is beaut, but you still will
  56 want to copy the symbol from the buffer to a more permanent
  57 symbol-table entry say about half the time.
  58
  59 With obstacks, you can work differently.  Use one obstack for all symbol
  60 names.  As you read a symbol, grow the name in the obstack gradually.
  61 When the name is complete, finalize it.  Then, if the symbol exists already,
  62 free the newly read name.
  63
  64 The way we do this is to take a large chunk, allocating memory from
  65 low addresses.  When you want to build a symbol in the chunk you just
  66 add chars above the current "high water mark" in the chunk.  When you
  67 have finished adding chars, because you got to the end of the symbol,
  68 you know how long the chars are, and you can create a new object.
  69 Mostly the chars will not burst over the highest address of the chunk,
  70 because you would typically expect a chunk to be (say) 100 times as
  71 long as an average object.
  72
  73 In case that isn't clear, when we have enough chars to make up
  74 the object, THEY ARE ALREADY CONTIGUOUS IN THE CHUNK (guaranteed)
  75 so we just point to it where it lies.  No moving of chars is
  76 needed and this is the second win: potentially long strings need
  77 never be explicitly shuffled. Once an object is formed, it does not
  78 change its address during its lifetime.
  79
  80 When the chars burst over a chunk boundary, we allocate a larger
  81 chunk, and then copy the partly formed object from the end of the old
  82 chunk to the beginning of the new larger chunk.  We then carry on
  83 accreting characters to the end of the object as we normally would.
  84
  85 A special macro is provided to add a single char at a time to a
  86 growing object.  This allows the use of register variables, which
  87 break the ordinary 'growth' macro.
  88
  89 Summary:
  90         We allocate large chunks.
  91         We carve out one object at a time from the current chunk.
  92         Once carved, an object never moves.
  93         We are free to append data of any size to the currently
  94           growing object.
  95         Exactly one object is growing in an obstack at any one time.
  96         You can run one obstack per control block.
  97         You may have as many control blocks as you dare.
  98         Because of the way we do it, you can `unwind' an obstack
  99           back to a previous state. (You may remove objects much
 100           as you would with a stack.)
 101 */
 102
 103
 104 /* Don't do the contents of this file more than once.  */
 105
 106 #ifndef _OBSTACK_H
 107 #define _OBSTACK_H 1
 108
 109 #ifdef __cplusplus
 110 extern "C" {
 111 #endif
 112 \f
 113 /* We use subtraction of (char *) 0 instead of casting to int
 114    because on word-addressable machines a simple cast to int
 115    may ignore the byte-within-word field of the pointer.  */
 116
 117 #ifndef __PTR_TO_INT
 118 # define __PTR_TO_INT(P) ((P) - (char *) 0)
 119 #endif
 120
 121 #ifndef __INT_TO_PTR
 122 # define __INT_TO_PTR(P) ((P) + (char *) 0)
 123 #endif
 124
 125 /* We need the type of the resulting object.  If __PTRDIFF_TYPE__ is
 126    defined, as with GNU C, use that; that way we don't pollute the
 127    namespace with <stddef.h>'s symbols.  Otherwise, if <stddef.h> is
 128    available, include it and use ptrdiff_t.  In traditional C, long is
 129    the best that we can do.  */
 130
 131 #ifdef __PTRDIFF_TYPE__
 132 # define PTR_INT_TYPE __PTRDIFF_TYPE__
 133 #else
 134 # ifdef HAVE_STDDEF_H
 135 #  include <stddef.h>
 136 #  define PTR_INT_TYPE ptrdiff_t
 137 # else
 138 #  define PTR_INT_TYPE long
 139 # endif
 140 #endif
 141
 142 #if defined _LIBC || defined HAVE_STRING_H
 143 # include <string.h>
 144 # define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 145 #else
 146 # ifdef memcpy
 147 #  define _obstack_memcpy(To, From, N) memcpy ((To), (From), (N))
 148 # else
 149 #  define _obstack_memcpy(To, From, N) bcopy ((From), (To), (N))
 150 # endif
 151 #endif
 152
 153 struct _obstack_chunk           /* Lives at front of each chunk. */
 154 {
 155   char  *limit;                 /* 1 past end of this chunk */
 156   struct _obstack_chunk *prev;  /* address of prior chunk or NULL */
 157   char  contents[4];            /* objects begin here */
 158 };
 159
 160 struct obstack          /* control current object in current chunk */
 161 {
 162   long  chunk_size;             /* preferred size to allocate chunks in */
 163   struct _obstack_chunk *chunk; /* address of current struct obstack_chunk */
 164   char  *object_base;           /* address of object we are building */
 165   char  *next_free;             /* where to add next char to current object */
 166   char  *chunk_limit;           /* address of char after current chunk */
 167   PTR_INT_TYPE temp;            /* Temporary for some macros.  */
 168   int   alignment_mask;         /* Mask of alignment for each object. */
 169 #if defined __STDC__ && __STDC__
 170   /* These prototypes vary based on `use_extra_arg', and we use
 171      casts to the prototypeless function type in all assignments,
 172      but having prototypes here quiets -Wstrict-prototypes.  */
 173   struct _obstack_chunk *(*chunkfun) (void *, long);
 174   void (*freefun) (void *, struct _obstack_chunk *);
 175   void *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 176 #else
 177   struct _obstack_chunk *(*chunkfun) (); /* User's fcn to allocate a chunk.  */
 178   void (*freefun) ();           /* User's function to free a chunk.  */
 179   char *extra_arg;              /* first arg for chunk alloc/dealloc funcs */
 180 #endif
 181   unsigned use_extra_arg:1;     /* chunk alloc/dealloc funcs take extra arg */
 182   unsigned maybe_empty_object:1;/* There is a possibility that the current
 183                                    chunk contains a zero-length object.  This
 184                                    prevents freeing the chunk if we allocate
 185                                    a bigger chunk to replace it. */
 186   unsigned alloc_failed:1;      /* No longer used, as we now call the failed
 187                                    handler on error, but retained for binary
 188                                    compatibility.  */
 189 };
 190
 191 /* Declare the external functions we use; they are in obstack.c.  */
 192
 193 #if defined __STDC__ && __STDC__
 194 extern void _obstack_newchunk (struct obstack *, int);
 195 extern void _obstack_free (struct obstack *, void *);
 196 extern int _obstack_begin (struct obstack *, int, int,
 197                             void *(*) (long), void (*) (void *));
 198 extern int _obstack_begin_1 (struct obstack *, int, int,
 199                              void *(*) (void *, long),
 200                              void (*) (void *, void *), void *);
 201 extern int _obstack_memory_used (struct obstack *);
 202 #else
 203 extern void _obstack_newchunk ();
 204 extern void _obstack_free ();
 205 extern int _obstack_begin ();
 206 extern int _obstack_begin_1 ();
 207 extern int _obstack_memory_used ();
 208 #endif
 209 \f
 210 #if defined __STDC__ && __STDC__
 211
 212 /* Do the function-declarations after the structs
 213    but before defining the macros.  */
 214
 215 void obstack_init (struct obstack *obstack);
 216
 217 void * obstack_alloc (struct obstack *obstack, int size);
 218
 219 void * obstack_copy (struct obstack *obstack, const void *address, int size);
 220 void * obstack_copy0 (struct obstack *obstack, const void *address, int size);
 221
 222 void obstack_free (struct obstack *obstack, void *block);
 223
 224 void obstack_blank (struct obstack *obstack, int size);
 225
 226 void obstack_grow (struct obstack *obstack, const void *data, int size);
 227 void obstack_grow0 (struct obstack *obstack, const void *data, int size);
 228
 229 void obstack_1grow (struct obstack *obstack, int data_char);
 230 void obstack_ptr_grow (struct obstack *obstack, const void *data);
 231 void obstack_int_grow (struct obstack *obstack, int data);
 232
 233 void * obstack_finish (struct obstack *obstack);
 234
 235 int obstack_object_size (struct obstack *obstack);
 236
 237 int obstack_room (struct obstack *obstack);
 238 void obstack_make_room (struct obstack *obstack, int size);
 239 void obstack_1grow_fast (struct obstack *obstack, int data_char);
 240 void obstack_ptr_grow_fast (struct obstack *obstack, const void *data);
 241 void obstack_int_grow_fast (struct obstack *obstack, int data);
 242 void obstack_blank_fast (struct obstack *obstack, int size);
 243
 244 void * obstack_base (struct obstack *obstack);
 245 void * obstack_next_free (struct obstack *obstack);
 246 int obstack_alignment_mask (struct obstack *obstack);
 247 int obstack_chunk_size (struct obstack *obstack);
 248 int obstack_memory_used (struct obstack *obstack);
 249
 250 #endif /* __STDC__ */
 251
 252 /* Non-ANSI C cannot really support alternative functions for these macros,
 253    so we do not declare them.  */
 254
 255 /* Error handler called when `obstack_chunk_alloc' failed to allocate
 256    more memory.  This can be set to a user defined function which
 257    should either abort gracefully or use longjump - but shouldn't
 258    return.  The default action is to print a message and abort.  */
 259 #if defined __STDC__ && __STDC__
 260 extern void (*obstack_alloc_failed_handler) (void);
 261 #else
 262 extern void (*obstack_alloc_failed_handler) ();
 263 #endif
 264
 265 /* Exit value used when `print_and_abort' is used.  */
 266 extern int obstack_exit_failure;
 267 \f
 268 /* Pointer to beginning of object being allocated or to be allocated next.
 269    Note that this might not be the final address of the object
 270    because a new chunk might be needed to hold the final size.  */
 271
 272 #define obstack_base(h) ((h)->object_base)
 273
 274 /* Size for allocating ordinary chunks.  */
 275
 276 #define obstack_chunk_size(h) ((h)->chunk_size)
 277
 278 /* Pointer to next byte not yet allocated in current chunk.  */
 279
 280 #define obstack_next_free(h)    ((h)->next_free)
 281
 282 /* Mask specifying low bits that should be clear in address of an object.  */
 283
 284 #define obstack_alignment_mask(h) ((h)->alignment_mask)
 285
 286 /* To prevent prototype warnings provide complete argument list in
 287    standard C version.  */
 288 #if defined __STDC__ && __STDC__
 289
 290 # define obstack_init(h)                                        \
 291   _obstack_begin ((h), 0, 0,                                    \
 292                   (void *(*) (long)) obstack_chunk_alloc,       \
 293                   (void (*) (void *)) obstack_chunk_free)
 294
 295 # define obstack_begin(h, size)                                 \
 296   _obstack_begin ((h), (size), 0,                               \
 297                   (void *(*) (long)) obstack_chunk_alloc,       \
 298                   (void (*) (void *)) obstack_chunk_free)
 299
 300 # define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 301   _obstack_begin ((h), (size), (alignment),                                \
 302                   (void *(*) (long)) (chunkfun),                           \
 303                   (void (*) (void *)) (freefun))
 304
 305 # define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 306   _obstack_begin_1 ((h), (size), (alignment),                           \
 307                     (void *(*) (void *, long)) (chunkfun),              \
 308                     (void (*) (void *, void *)) (freefun), (arg))
 309
 310 # define obstack_chunkfun(h, newchunkfun) \
 311   ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
 312
 313 # define obstack_freefun(h, newfreefun) \
 314   ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
 315
 316 #else
 317
 318 # define obstack_init(h)                                                \
 319   _obstack_begin ((h), 0, 0,                                            \
 320                   (void *(*) ()) obstack_chunk_alloc,                   \
 321                   (void (*) ()) obstack_chunk_free)
 322
 323 # define obstack_begin(h, size)                                         \
 324   _obstack_begin ((h), (size), 0,                                       \
 325                   (void *(*) ()) obstack_chunk_alloc,                   \
 326                   (void (*) ()) obstack_chunk_free)
 327
 328 # define obstack_specify_allocation(h, size, alignment, chunkfun, freefun) \
 329   _obstack_begin ((h), (size), (alignment),                                \
 330                   (void *(*) ()) (chunkfun),                               \
 331                   (void (*) ()) (freefun))
 332
 333 # define obstack_specify_allocation_with_arg(h, size, alignment, chunkfun, freefun, arg) \
 334   _obstack_begin_1 ((h), (size), (alignment),                           \
 335                     (void *(*) ()) (chunkfun),                          \
 336                     (void (*) ()) (freefun), (arg))
 337
 338 # define obstack_chunkfun(h, newchunkfun) \
 339   ((h) -> chunkfun = (struct _obstack_chunk *(*)()) (newchunkfun))
 340
 341 # define obstack_freefun(h, newfreefun) \
 342   ((h) -> freefun = (void (*)()) (newfreefun))
 343
 344 #endif
 345
 346 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = achar)
 347
 348 #define obstack_blank_fast(h,n) ((h)->next_free += (n))
 349
 350 #define obstack_memory_used(h) _obstack_memory_used (h)
 351 \f
 352 #if defined __GNUC__ && defined __STDC__ && __STDC__
 353 /* NextStep 2.0 cc is really gcc 1.93 but it defines __GNUC__ = 2 and
 354    does not implement __extension__.  But that compiler doesn't define
 355    __GNUC_MINOR__.  */
 356 # if __GNUC__ < 2 || (__NeXT__ && !__GNUC_MINOR__)
 357 #  define __extension__
 358 # endif
 359
 360 /* For GNU C, if not -traditional,
 361    we can define these macros to compute all args only once
 362    without using a global variable.
 363    Also, we can avoid using the `temp' slot, to make faster code.  */
 364
 365 # define obstack_object_size(OBSTACK)                                   \
 366   __extension__                                                         \
 367   ({ struct obstack *__o = (OBSTACK);                                   \
 368      (unsigned) (__o->next_free - __o->object_base); })
 369
 370 # define obstack_room(OBSTACK)                                          \
 371   __extension__                                                         \
 372   ({ struct obstack *__o = (OBSTACK);                                   \
 373      (unsigned) (__o->chunk_limit - __o->next_free); })
 374
 375 # define obstack_make_room(OBSTACK,length)                              \
 376 __extension__                                                           \
 377 ({ struct obstack *__o = (OBSTACK);                                     \
 378    int __len = (length);                                                \
 379    if (__o->chunk_limit - __o->next_free < __len)                       \
 380      _obstack_newchunk (__o, __len);                                    \
 381    (void) 0; })
 382
 383 # define obstack_empty_p(OBSTACK)                                       \
 384   __extension__                                                         \
 385   ({ struct obstack *__o = (OBSTACK);                                   \
 386      (__o->chunk->prev == 0 && __o->next_free - __o->chunk->contents == 0); })
 387
 388 # define obstack_grow(OBSTACK,where,length)                             \
 389 __extension__                                                           \
 390 ({ struct obstack *__o = (OBSTACK);                                     \
 391    int __len = (length);                                                \
 392    if (__o->next_free + __len > __o->chunk_limit)                       \
 393      _obstack_newchunk (__o, __len);                                    \
 394    _obstack_memcpy (__o->next_free, (where), __len);                    \
 395    __o->next_free += __len;                                             \
 396    (void) 0; })
 397
 398 # define obstack_grow0(OBSTACK,where,length)                            \
 399 __extension__                                                           \
 400 ({ struct obstack *__o = (OBSTACK);                                     \
 401    int __len = (length);                                                \
 402    if (__o->next_free + __len + 1 > __o->chunk_limit)                   \
 403      _obstack_newchunk (__o, __len + 1);                                \
 404    _obstack_memcpy (__o->next_free, (where), __len);                    \
 405    __o->next_free += __len;                                             \
 406    *(__o->next_free)++ = 0;                                             \
 407    (void) 0; })
 408
 409 # define obstack_1grow(OBSTACK,datum)                                   \
 410 __extension__                                                           \
 411 ({ struct obstack *__o = (OBSTACK);                                     \
 412    if (__o->next_free + 1 > __o->chunk_limit)                           \
 413      _obstack_newchunk (__o, 1);                                        \
 414    *(__o->next_free)++ = (datum);                                       \
 415    (void) 0; })
 416
 417 /* These assume that the obstack alignment is good enough for pointers
 418    or ints, and that the data added so far to the current object
 419    shares that much alignment.  */
 420
 421 # define obstack_ptr_grow(OBSTACK,datum)                                \
 422 __extension__                                                           \
 423 ({ struct obstack *__o = (OBSTACK);                                     \
 424    if (__o->next_free + sizeof (void *) > __o->chunk_limit)             \
 425      _obstack_newchunk (__o, sizeof (void *));                          \
 426    *((void **)__o->next_free)++ = (datum);                              \
 427    (void) 0; })
 428
 429 # define obstack_int_grow(OBSTACK,datum)                                \
 430 __extension__                                                           \
 431 ({ struct obstack *__o = (OBSTACK);                                     \
 432    if (__o->next_free + sizeof (int) > __o->chunk_limit)                \
 433      _obstack_newchunk (__o, sizeof (int));                             \
 434    *((int *)__o->next_free)++ = (datum);                                \
 435    (void) 0; })
 436
 437 # define obstack_ptr_grow_fast(h,aptr)                                  \
 438   (*((void **) (h)->next_free)++ = (aptr))
 439
 440 # define obstack_int_grow_fast(h,aint)                                  \
 441   (*((int *) (h)->next_free)++ = (aint))
 442
 443 # define obstack_blank(OBSTACK,length)                                  \
 444 __extension__                                                           \
 445 ({ struct obstack *__o = (OBSTACK);                                     \
 446    int __len = (length);                                                \
 447    if (__o->chunk_limit - __o->next_free < __len)                       \
 448      _obstack_newchunk (__o, __len);                                    \
 449    __o->next_free += __len;                                             \
 450    (void) 0; })
 451
 452 # define obstack_alloc(OBSTACK,length)                                  \
 453 __extension__                                                           \
 454 ({ struct obstack *__h = (OBSTACK);                                     \
 455    obstack_blank (__h, (length));                                       \
 456    obstack_finish (__h); })
 457
 458 # define obstack_copy(OBSTACK,where,length)                             \
 459 __extension__                                                           \
 460 ({ struct obstack *__h = (OBSTACK);                                     \
 461    obstack_grow (__h, (where), (length));                               \
 462    obstack_finish (__h); })
 463
 464 # define obstack_copy0(OBSTACK,where,length)                            \
 465 __extension__                                                           \
 466 ({ struct obstack *__h = (OBSTACK);                                     \
 467    obstack_grow0 (__h, (where), (length));                              \
 468    obstack_finish (__h); })
 469
 470 /* The local variable is named __o1 to avoid a name conflict
 471    when obstack_blank is called.  */
 472 # define obstack_finish(OBSTACK)                                        \
 473 __extension__                                                           \
 474 ({ struct obstack *__o1 = (OBSTACK);                                    \
 475    void *value;                                                         \
 476    value = (void *) __o1->object_base;                                  \
 477    if (__o1->next_free == value)                                        \
 478      __o1->maybe_empty_object = 1;                                      \
 479    __o1->next_free                                                      \
 480      = __INT_TO_PTR ((__PTR_TO_INT (__o1->next_free)+__o1->alignment_mask)\
 481                      & ~ (__o1->alignment_mask));                       \
 482    if (__o1->next_free - (char *)__o1->chunk                            \
 483        > __o1->chunk_limit - (char *)__o1->chunk)                       \
 484      __o1->next_free = __o1->chunk_limit;                               \
 485    __o1->object_base = __o1->next_free;                                 \
 486    value; })
 487
 488 # define obstack_free(OBSTACK, OBJ)                                     \
 489 __extension__                                                           \
 490 ({ struct obstack *__o = (OBSTACK);                                     \
 491    void *__obj = (OBJ);                                                 \
 492    if (__obj > (void *)__o->chunk && __obj < (void *)__o->chunk_limit)  \
 493      __o->next_free = __o->object_base = (char *)__obj;                 \
 494    else (obstack_free) (__o, __obj); })
 495 \f
 496 #else /* not __GNUC__ or not __STDC__ */
 497
 498 # define obstack_object_size(h) \
 499  (unsigned) ((h)->next_free - (h)->object_base)
 500
 501 # define obstack_room(h)                \
 502  (unsigned) ((h)->chunk_limit - (h)->next_free)
 503
 504 # define obstack_empty_p(h) \
 505  ((h)->chunk->prev == 0 && (h)->next_free - (h)->chunk->contents == 0)
 506
 507 /* Note that the call to _obstack_newchunk is enclosed in (..., 0)
 508    so that we can avoid having void expressions
 509    in the arms of the conditional expression.
 510    Casting the third operand to void was tried before,
 511    but some compilers won't accept it.  */
 512
 513 # define obstack_make_room(h,length)                                    \
 514 ( (h)->temp = (length),                                                 \
 515   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 516    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0))
 517
 518 # define obstack_grow(h,where,length)                                   \
 519 ( (h)->temp = (length),                                                 \
 520   (((h)->next_free + (h)->temp > (h)->chunk_limit)                      \
 521    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 522   _obstack_memcpy ((h)->next_free, (where), (h)->temp),                 \
 523   (h)->next_free += (h)->temp)
 524
 525 # define obstack_grow0(h,where,length)                                  \
 526 ( (h)->temp = (length),                                                 \
 527   (((h)->next_free + (h)->temp + 1 > (h)->chunk_limit)                  \
 528    ? (_obstack_newchunk ((h), (h)->temp + 1), 0) : 0),                  \
 529   _obstack_memcpy ((h)->next_free, (where), (h)->temp),                 \
 530   (h)->next_free += (h)->temp,                                          \
 531   *((h)->next_free)++ = 0)
 532
 533 # define obstack_1grow(h,datum)                                         \
 534 ( (((h)->next_free + 1 > (h)->chunk_limit)                              \
 535    ? (_obstack_newchunk ((h), 1), 0) : 0),                              \
 536   (*((h)->next_free)++ = (datum)))
 537
 538 # define obstack_ptr_grow(h,datum)                                      \
 539 ( (((h)->next_free + sizeof (char *) > (h)->chunk_limit)                \
 540    ? (_obstack_newchunk ((h), sizeof (char *)), 0) : 0),                \
 541   (*((const char **) (((h)->next_free+=sizeof(char *))-sizeof(char *))) = (datum)))
 542
 543 # define obstack_int_grow(h,datum)                                      \
 544 ( (((h)->next_free + sizeof (int) > (h)->chunk_limit)                   \
 545    ? (_obstack_newchunk ((h), sizeof (int)), 0) : 0),                   \
 546   (*((int *) (((h)->next_free+=sizeof(int))-sizeof(int))) = (datum)))
 547
 548 # define obstack_ptr_grow_fast(h,aptr)                                  \
 549   (*((const char **) (h)->next_free)++ = (aptr))
 550
 551 # define obstack_int_grow_fast(h,aint)                                  \
 552   (*((int *) (h)->next_free)++ = (aint))
 553
 554 # define obstack_blank(h,length)                                        \
 555 ( (h)->temp = (length),                                                 \
 556   (((h)->chunk_limit - (h)->next_free < (h)->temp)                      \
 557    ? (_obstack_newchunk ((h), (h)->temp), 0) : 0),                      \
 558   ((h)->next_free += (h)->temp))
 559
 560 # define obstack_alloc(h,length)                                        \
 561  (obstack_blank ((h), (length)), obstack_finish ((h)))
 562
 563 # define obstack_copy(h,where,length)                                   \
 564  (obstack_grow ((h), (where), (length)), obstack_finish ((h)))
 565
 566 # define obstack_copy0(h,where,length)                                  \
 567  (obstack_grow0 ((h), (where), (length)), obstack_finish ((h)))
 568
 569 # define obstack_finish(h)                                              \
 570 ( ((h)->next_free == (h)->object_base                                   \
 571    ? (((h)->maybe_empty_object = 1), 0)                                 \
 572    : 0),                                                                \
 573   (h)->temp = __PTR_TO_INT ((h)->object_base),                          \
 574   (h)->next_free                                                        \
 575     = __INT_TO_PTR ((__PTR_TO_INT ((h)->next_free)+(h)->alignment_mask) \
 576                     & ~ ((h)->alignment_mask)),                         \
 577   (((h)->next_free - (char *) (h)->chunk                                \
 578     > (h)->chunk_limit - (char *) (h)->chunk)                           \
 579    ? ((h)->next_free = (h)->chunk_limit) : 0),                          \
 580   (h)->object_base = (h)->next_free,                                    \
 581   __INT_TO_PTR ((h)->temp))
 582
 583 # if defined __STDC__ && __STDC__
 584 #  define obstack_free(h,obj)                                           \
 585 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 586   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 587    ? (int) ((h)->next_free = (h)->object_base                           \
 588             = (h)->temp + (char *) (h)->chunk)                          \
 589    : (((obstack_free) ((h), (h)->temp + (char *) (h)->chunk), 0), 0)))
 590 # else
 591 #  define obstack_free(h,obj)                                           \
 592 ( (h)->temp = (char *) (obj) - (char *) (h)->chunk,                     \
 593   (((h)->temp > 0 && (h)->temp < (h)->chunk_limit - (char *) (h)->chunk)\
 594    ? (int) ((h)->next_free = (h)->object_base                           \
 595             = (h)->temp + (char *) (h)->chunk)                          \
 596    : (_obstack_free ((h), (h)->temp + (char *) (h)->chunk), 0)))
 597 # endif
 598
 599 #endif /* not __GNUC__ or not __STDC__ */
 600
 601 #ifdef __cplusplus
 602 }       /* C++ */
 603 #endif
 604
 605 #endif /* obstack.h */